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Sample records for advanced mirror system

  1. Advanced Mirror System Demonstrator (AMSD) Risk Management

    NASA Technical Reports Server (NTRS)

    Byberg, Alicia; Russell, J. Kevin; Kaukler, Donna; Burdine, Robert V. (Technical Monitor)

    2002-01-01

    This paper will report risk issues associated with designing, manufacturing, and testing the Advanced Mirror System Demonstrator (AMSD). The Advanced Mirror System Demonstrator (AMSD) will be developed as a lightweight primary mirror system that can be produced at a low cost and with a short manufacturing schedule. This technology will add to the knowledge base for selection for the Next Generation Space Telescope (NGST), Space Based Laser (SBL), Research Laboratory mission (AFRL), and other government agency programs.

  2. C/SiC advanced mirror system demonstrator design

    NASA Astrophysics Data System (ADS)

    Catanzaro, Brian E.; Mehle, Gregory V.; Seilonen, Martin A.; Papenburg, Ulrich; Mueller, Claus E.; Pfrang, Wilhelm; Kutter, G. Siegfried; Ruch, Eric; Mercier, Renaud; Lightsey, Paul A.; Streetman, Scott; Neam, Douglas C.

    2000-07-01

    Challenges in high-resolution space telescopes have led to the desire to create large primary mirror apertures. One such telescope is the Next Generation Space Telescope (NGST, 8-m primary). In order to accommodate launch vehicles, the optical systems using these large apertures are being designed to accommodate extremely lightweight, deployable, segmented primary mirrors. The requirements for these segments include: meter-class diameter, areal densities of the order of 15 kg/m2, aspheric surface figure, near infrared and visible spectrum operation, diffraction limited surface figure, high stiffness, tight radius of curvature matching, and excellent thermal stability. Operating temperatures for various systems include ambient as well as cryogenic ranges. A unique ceramic, carbon fiber reinforced silicon carbide, developed by the Industrieanlagen- Betriebsgesellschaft mbH, has shown potential for use as a mirror substrate. This paper presents the deign and predicted performance of this mirror system in various applications. Also included are issues related to the fabrication of the Advanced Mirror System Demonstrator.

  3. Ball Semi-Rigid Advanced Mirror System Demonstrator (AMSD)

    NASA Technical Reports Server (NTRS)

    Kendrick, Stephen; Russell, Kevin (Technical Monitor)

    2001-01-01

    The AMSD Program is to design, fabricate, and test a 1.4-m point-to-point hexagon mirror system. The Ball semi-rigid approach will be described and its current status presented, The mirror system includes a lightweighted beryllium mirror that is attached through flexures and actuators to a composite reaction structure enabling optical performance at ambient and cryogenic temperatures and allowing changes of curvature to be imposed via actuation. This program is administered through NASA MSFC and is jointly funded by NASA, the USAF, and the NRO.

  4. Managing Risk on a Technology Development Project/Advanced Mirror System Demonstrator

    NASA Technical Reports Server (NTRS)

    Byberg, Alicia; Russell, J. Kevin; Stahl, Phil (Technical Monitor)

    2002-01-01

    The risk management study applied to the Advanced Mirror System Demonstrator (AMSD), a precursor mirror technology development for the Next Generation Space Telescope (NGST) is documented. The AMSD will be developed as a segment of a lightweight primary mirror system that can be produced at a low cost and with a short manufacturing schedule. The technology gained from the program will support the risk mitigation strategy for the NGST, as well as other government agency space mirror programs.

  5. Advanced metal mirror processing for tactical ISR systems

    NASA Astrophysics Data System (ADS)

    Schaefer, John P.

    2013-05-01

    Using its patented VQ™ finishing process, Raytheon EO Innovations has been producing low-scatter, low-figure and affordable aluminum 6061-based mirrors for long stand-off intelligence, surveillance and reconnaissance (ISR) systems in production since 2005. These common aperture multispectral systems require λ/30 root mean square (RMS) surface figure and sub-20Å RMS finishes for optimal visible imaging performance. This paper discusses the process results, scatter performance, and fabrication capabilities of Multispectral Reflective Lightweight Optics Technology (MeRLOT™), a new lightweight substrate material. This new technology enables lightweight, common-aperture, broadband performance that can be put in the hands of the warfighter for precision targeting and surveillance operations.

  6. Design of GA thermochemical water-splitting process for the Mirror Advanced Reactor System

    SciTech Connect

    Brown, L.C.

    1983-04-01

    GA interfaced the sulfur-iodine thermochemical water-splitting cycle to the Mirror Advanced Reactor System (MARS). The results of this effort follow as one section and part of a second section to be included in the MARS final report. This section describes the process and its interface to the reactor. The capital and operating costs for the hydrogen plant are described.

  7. Alignment of an aspheric mirror subsystem for an advanced infrared catadioptric system

    NASA Astrophysics Data System (ADS)

    Tingstad, James S.

    1991-12-01

    With many optical systems the method that is used to align the optical system needs to be an integral portion of the system design and not an afterthought. Once all the pieces are in fabrication it may be too late to implement a cost-effective alignment procedure for both prototype and production designs. This is especially true with catadioptric systems where the mirror alignment tends to be very critical as far as system performance is concerned. This paper describes the design and use of an aspheric null mirror for the alignment of a two mirror subsystem to a lens cell. The optical system to be aligned was a six-in. EFL, F/2 system working in the 3-5 micrometers bandpass. It consisted of two aspheric mirrors, one aspheric lens, and two spherical lenses.

  8. Advanced Mirror & Modelling Technology Development

    NASA Technical Reports Server (NTRS)

    Effinger, Michael; Stahl, H. Philip; Abplanalp, Laura; Maffett, Steven; Egerman, Robert; Eng, Ron; Arnold, William; Mosier, Gary; Blaurock, Carl

    2014-01-01

    The 2020 Decadal technology survey is starting in 2018. Technology on the shelf at that time will help guide selection to future low risk and low cost missions. The Advanced Mirror Technology Development (AMTD) team has identified development priorities based on science goals and engineering requirements for Ultraviolet Optical near-Infrared (UVOIR) missions in order to contribute to the selection process. One key development identified was lightweight mirror fabrication and testing. A monolithic, stacked, deep core mirror was fused and replicated twice to achieve the desired radius of curvature. It was subsequently successfully polished and tested. A recently awarded second phase to the AMTD project will develop larger mirrors to demonstrate the lateral scaling of the deep core mirror technology. Another key development was rapid modeling for the mirror. One model focused on generating optical and structural model results in minutes instead of months. Many variables could be accounted for regarding the core, face plate and back structure details. A portion of a spacecraft model was also developed. The spacecraft model incorporated direct integration to transform optical path difference to Point Spread Function (PSF) and between PSF to modulation transfer function. The second phase to the project will take the results of the rapid mirror modeler and integrate them into the rapid spacecraft modeler.

  9. Analytical Verifications in Cryogenic Testing of NGST Advanced Mirror System Demonstrators

    NASA Technical Reports Server (NTRS)

    Cummings, Ramona; Levine, Marie; VanBuren, Dave; Kegley, Jeff; Green, Joseph; Hadaway, James; Presson, Joan; Cline, Todd; Stahl, H. Philip (Technical Monitor)

    2002-01-01

    Ground based testing is a critical and costly part of component, assembly, and system verifications of large space telescopes. At such tests, however, with integral teamwork by planners, analysts, and test personnel, segments can be included to validate specific analytical parameters and algorithms at relatively low additional cost. This paper opens with strategy of analytical verification segments added to vacuum cryogenic testing of Advanced Mirror System Demonstrator (AMSD) assemblies. These AMSD assemblies incorporate material and architecture concepts being considered in the Next Generation Space Telescope (NGST) design. The test segments for workmanship testing, cold survivability, and cold operation optical throughput are supplemented by segments for analytical verifications of specific structural, thermal, and optical parameters. Utilizing integrated modeling and separate materials testing, the paper continues with support plan for analyses, data, and observation requirements during the AMSD testing, currently slated for late calendar year 2002 to mid calendar year 2003. The paper includes anomaly resolution as gleaned by authors from similar analytical verification support of a previous large space telescope, then closes with draft of plans for parameter extrapolations, to form a well-verified portion of the integrated modeling being done for NGST performance predictions.

  10. Vibratory response of a mirror support/positioning system for the Advanced Photon Source project at Argonne National Laboratory

    SciTech Connect

    Basdogan, I.; Shu, Deming; Kuzay, T.M.; Royston, T.J.; Shabana, A.A.

    1996-08-01

    The vibratory response of a typical mirror support/positioning system used at the experimental station of the Advanced Photon Source (APS) project at Argonne National Laboratory is investigated. Positioning precision and stability are especially critical when the supported mirror directs a high-intensity beam aimed at a distant target. Stability may be compromised by low level, low frequency seismic and facility-originated vibrations traveling through the ground and/or vibrations caused by flow-structure interactions in the mirror cooling system. The example case system has five positioning degrees of freedom through the use of precision actuators and rotary and linear bearings. These linkage devices result in complex, multi-dimensional vibratory behavior that is a function of the range of positioning configurations. A rigorous multibody dynamical approach is used for the development of the system equations. Initial results of the study, including estimates of natural frequencies and mode shapes, as well as limited parametric design studies, are presented. While the results reported here are for a particular system, the developed vibratory analysis approach is applicable to the wide range of high-precision optical positioning systems encountered at the APS and at other comparable facilities.

  11. Advancement of the segment support system for the Thirty Meter Telescope primary mirror

    NASA Astrophysics Data System (ADS)

    Williams, Eric C.; Baffes, Curtis; Mast, Terry; Nelson, Jerry; Platt, Benjamin; Ponchione, R. J.; Ponslet, Eric; Setoodeh, Shahriar; Sirota, Mark; Stephens, Vince; Stepp, Larry; Tubb, Alan

    2008-07-01

    This paper presents refinements to the design of the TMT primary mirror segment passive-support system that are effective in reducing gravity print-through and thermal distortion effects. First, a novel analytical method is presented for tuning the axial and lateral support systems in a manner that results in improved optical performance when subject to varying gravity fields. The method utilizes counterweights attached to the whiffletrees to cancel astigmatic and comatic errors normally resulting when the lateral support system resists transverse loads induced by gravity. Secondly, several central diaphragm designs are presented and analyzed to assess lateral-gravity and thermal distortion performance: 1) a simple flat diaphragm, 2) a stress-relieving diaphragm having a slotted outer rim and a circumferential convolution near the outside diameter, and 3) a flat diaphragm having a slotted outer rim. The latter design is chosen based on results from analytical studies which show it to have better overall optical performance in the presence of gravity and thermal environments.

  12. Physics of mirror systems

    SciTech Connect

    Post, R.F.

    1982-05-01

    In recent years the emphasis in research on the magnetic mirror approach to fusion has been shifted to address what are essentially economically-motivated issues. The introduction of the Tandem Mirror idea solved in principal the problem of low Q (low fusion power gain) of mirror-based fusion systems. In order to optimize the tandem mirror idea from an economic standpoint, some important improvements have been suggested. These improvements include the thermal barrier idea of Baldwin and Logan and the axicell concept of Kesner. These new modifications introduce some special physics considerations. Among these are (1) The MHD stability properties of high energy electron components in the end cells; (2) The optimization of end-cell magnetic field configurations with the objective of minimizing equilibrium parallel currents; (3) The suppression of microstabilities by use of sloshing ion distributions. Following a brief outline of tandem mirror concepts, the above three topics are discussed, with illustrative examples taken from earlier work or from recent design studies.

  13. Mirror Advanced Reactor Study interim design report

    SciTech Connect

    Not Available

    1983-04-01

    The status of the design of a tenth-of-a-kind commercial tandem-mirror fusion reactor is described at the midpoint of a two-year study. When completed, the design is to serve as a strategic goal for the mirror fusion program. The main objectives of the Mirror Advanced Reactor Study (MARS) are: (1) to design an attractive tandem-mirror fusion reactor producing electricity and synfuels (in alternate versions), (2) to identify key development and technology needs, and (3) to exploit the potential of fusion for safety, low activation, and simple disposal of radioactive waste. In the first year we have emphasized physics and engineering of the central cell and physics of the end cell. Design optimization and trade studies are continuing, and we expect additional modifications in the end cells to further improve the performance of the final design.

  14. Gemini primary mirror support system

    NASA Astrophysics Data System (ADS)

    Stepp, Larry M.; Huang, Eugene W.; Cho, Myung K.

    1994-06-01

    The primary mirror selected for the Gemini 8-m Telescopes is a thin meniscus made of Corning ULE(superscript TM) glass. The conceptual design of the Gemini support system has evolved in response to the properties of the meniscus mirror and the functional requirements of the Gemini Telescopes. This paper describes the design requirements, the design features, and predicted performance of this system.

  15. Space Mirror Alignment System

    NASA Technical Reports Server (NTRS)

    Jau, Bruno M.; McKinney, Colin; Smythe, Robert F.; Palmer, Dean L.

    2011-01-01

    An optical alignment mirror mechanism (AMM) has been developed with angular positioning accuracy of +/-0.2 arcsec. This requires the mirror s linear positioning actuators to have positioning resolutions of +/-112 nm to enable the mirror to meet the angular tip/tilt accuracy requirement. Demonstrated capabilities are 0.1 arc-sec angular mirror positioning accuracy, which translates into linear positioning resolutions at the actuator of 50 nm. The mechanism consists of a structure with sets of cross-directional flexures that enable the mirror s tip and tilt motion, a mirror with its kinematic mount, and two linear actuators. An actuator comprises a brushless DC motor, a linear ball screw, and a piezoelectric brake that holds the mirror s position while the unit is unpowered. An interferometric linear position sensor senses the actuator s position. The AMMs were developed for an Astrometric Beam Combiner (ABC) optical bench, which is part of an interferometer development. Custom electronics were also developed to accommodate the presence of multiple AMMs within the ABC and provide a compact, all-in-one solution to power and control the AMMs.

  16. Advanced Mirror Technology Development (AMTD) for Very Large Space Telescopes

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2014-01-01

    Advanced Mirror Technology Development (AMTD) is a multi-year effort to systematically mature to TRL-6 the critical technologies needed to produce 4-m or larger flight-qualified UVOIR mirrors by 2018 so that a viable mission can be considered by the 2020 Decadal Review. This technology must enable missions capable of both general astrophysics & ultra-high contrast observations of exoplanets. To accomplish our objective, We use a science-driven systems engineering approach. We mature technologies required to enable the highest priority science AND result in a high-performance low-cost low-risk system.

  17. Two-mirror optical system with a small fold mirror

    NASA Astrophysics Data System (ADS)

    Liu, Xinping; Li, Yingcai; Yang, Jianfeng

    1998-09-01

    A new configuration of two-mirror optical system with a small fold mirror is presented in this paper. Consisting of a concave (positive power) primary mirror followed by a small flat mirror, a concave (positive power) secondary mirror, four lenses and a beam splitter, it gives the excellent image quality. A 1.5-m EFL, F/10 system of the upper configuration is designed over the 4 degree(s) field angle and 0.50 approximately 0.70 micrometers wavelength range. The aberrations have been highly corrected and the distortion is less than 0.3% over the field. The obscuration could be minimized by reducing primary radius of curvature and avoiding the spider that holds the small fold mirror.

  18. Integration of mirror design with suspension system using NASA's new mirror modeling software

    NASA Astrophysics Data System (ADS)

    Arnold, William R.; Bevan, Ryan M.; Stahl, H. Philip

    2013-09-01

    Advances in mirror fabrication are making very large space based telescopes possible. In many applications, only monolithic mirrors can meet the performance requirements. The existing and near-term planned heavy launch vehicles place a premium on lowest possible mass, and then available payload shroud sizes limit near term designs to 4 meter class mirrors. Practical 8 meter class and beyond designs could encourage planners to include larger shrouds, if it can be proven that such mirrors can be manufactured. These two factors, lower mass and larger mirrors, present the classic optimization problem. There is a practical upper limit to how large of a mirror can be supported by a purely kinematic mount system handling both operational and launch loads. This paper shows how the suspension system and mirror blank need to be designed simultaneously. We will also explore the concepts of auxiliary support systems which act only during launch and disengage on orbit. We will define required characteristics of these systems and show how they can substantially reduce the mirror mass.

  19. Integration of Mirror Design with Suspension System Using NASA's New Mirror Modeling Software

    NASA Technical Reports Server (NTRS)

    Arnold, William R., Sr.; Bevan, Ryan M.; Stahl, H. Philip

    2013-01-01

    Advances in mirror fabrication are making very large space based telescopes possible. In many applications, only monolithic mirrors can meet the performance requirements. The existing and near-term planned heavy launch vehicles place a premium on lowest possible mass, and then available payload shroud sizes limit near term designs to 4 meter class mirrors. Practical 8 meter class and beyond designs could encourage planners to include larger shrouds, if it can be proven that such mirrors can be manufactured. These two factors, lower mass and larger mirrors, present the classic optimization problem. There is a practical upper limit to how large of a mirror can be supported by a purely kinematic mount system handling both operational and launch loads. This paper shows how the suspension system and mirror blank need to be designed simultaneously. We will also explore the concepts of auxiliary support systems which act only during launch and disengage on orbit. We will define required characteristics of these systems and show how they can substantially reduce the mirror mass.

  20. Integration of Mirror Design with Suspension System using NASA's New Mirror Modeling Software

    NASA Technical Reports Server (NTRS)

    Arnold,William R., Sr.; Bevan, Ryan M.; Stahl, Philip

    2013-01-01

    Advances in mirror fabrication are making very large space based telescopes possible. In many applications, only monolithic mirrors can meet the performance requirements. The existing and near-term planned heavy launch vehicles place a premium on lowest possible mass, and then available payload shroud sizes limit near term designs to 4 meter class mirrors. Practical 8 meter class and beyond designs could encourage planners to include larger shrouds, if it can be proven that such mirrors can be manufactured. These two factors, lower mass and larger mirrors, present the classic optimization problem. There is a practical upper limit to how large of a mirror can be supported by a purely kinematic mount system handling both operational and launch loads. This paper shows how the suspension system and mirror blank need to be designed simultaneously. We will also explore the concepts of auxiliary support systems which act only during launch and disengage on orbit. We will define required characteristics of these systems and show how they can substantially reduce the mirror mass.

  1. [The ontogeny of the mirror neuron system].

    PubMed

    Myowa-Yamakoshi, Masako

    2014-06-01

    Abstract Humans utilize the mirror neuron system to understand and predict others' actions. However, the ontogeny of the mirror neuron system remains unknown. Whether mirror neuron function is an innate trait or whether mirror neurons acquire their sensorimotor matching properties ontogenetically remains to be clarified. In this paper, I review the ontogenetic theory of the mirror neuron system. I then discuss the functioning of the mirror neuron system in the context of social cognitive abilities, which are unique to humans. Recently, some researchers argue that it is too early to interpret the function of mirror neurons as an understanding of the underlying psychological states of others. They imply that such functioning would require inferential cognitive processes that are known to involve areas outside the mirror neuron system. Filling in this missing link may be the key to elucidating the unique ability of humans to understand others' actions.

  2. Robotic Mirror Therapy System for Functional Recovery of Hemiplegic Arms.

    PubMed

    Beom, Jaewon; Koh, Sukgyu; Nam, Hyung Seok; Kim, Wonshik; Kim, Yoonjae; Seo, Han Gil; Oh, Byung-Mo; Chung, Sun Gun; Kim, Sungwan

    2016-08-15

    Mirror therapy has been performed as effective occupational therapy in a clinical setting for functional recovery of a hemiplegic arm after stroke. It is conducted by eliciting an illusion through use of a mirror as if the hemiplegic arm is moving in real-time while moving the healthy arm. It can facilitate brain neuroplasticity through activation of the sensorimotor cortex. However, conventional mirror therapy has a critical limitation in that the hemiplegic arm is not actually moving. Thus, we developed a real-time 2-axis mirror robot system as a simple add-on module for conventional mirror therapy using a closed feedback mechanism, which enables real-time movement of the hemiplegic arm. We used 3 Attitude and Heading Reference System sensors, 2 brushless DC motors for elbow and wrist joints, and exoskeletal frames. In a feasibility study on 6 healthy subjects, robotic mirror therapy was safe and feasible. We further selected tasks useful for activities of daily living training through feedback from rehabilitation doctors. A chronic stroke patient showed improvement in the Fugl-Meyer assessment scale and elbow flexor spasticity after a 2-week application of the mirror robot system. Robotic mirror therapy may enhance proprioceptive input to the sensory cortex, which is considered to be important in neuroplasticity and functional recovery of hemiplegic arms. The mirror robot system presented herein can be easily developed and utilized effectively to advance occupational therapy.

  3. Robotic Mirror Therapy System for Functional Recovery of Hemiplegic Arms.

    PubMed

    Beom, Jaewon; Koh, Sukgyu; Nam, Hyung Seok; Kim, Wonshik; Kim, Yoonjae; Seo, Han Gil; Oh, Byung-Mo; Chung, Sun Gun; Kim, Sungwan

    2016-01-01

    Mirror therapy has been performed as effective occupational therapy in a clinical setting for functional recovery of a hemiplegic arm after stroke. It is conducted by eliciting an illusion through use of a mirror as if the hemiplegic arm is moving in real-time while moving the healthy arm. It can facilitate brain neuroplasticity through activation of the sensorimotor cortex. However, conventional mirror therapy has a critical limitation in that the hemiplegic arm is not actually moving. Thus, we developed a real-time 2-axis mirror robot system as a simple add-on module for conventional mirror therapy using a closed feedback mechanism, which enables real-time movement of the hemiplegic arm. We used 3 Attitude and Heading Reference System sensors, 2 brushless DC motors for elbow and wrist joints, and exoskeletal frames. In a feasibility study on 6 healthy subjects, robotic mirror therapy was safe and feasible. We further selected tasks useful for activities of daily living training through feedback from rehabilitation doctors. A chronic stroke patient showed improvement in the Fugl-Meyer assessment scale and elbow flexor spasticity after a 2-week application of the mirror robot system. Robotic mirror therapy may enhance proprioceptive input to the sensory cortex, which is considered to be important in neuroplasticity and functional recovery of hemiplegic arms. The mirror robot system presented herein can be easily developed and utilized effectively to advance occupational therapy. PMID:27583794

  4. Mirror mounts designed for the Advanced Photon Source SRI-CAT

    SciTech Connect

    Shu, D.; Benson, C.; Chang, J.

    1997-09-01

    Use of a mirror for beamlines at third-generation synchrotron radiation facilities, such as the Advanced Photon Source (APS) at Argonne National laboratory, has many advantages. A mirror as a first optical component provides significant reduction in the beam peak heat flux and total power on the downstream monochromator and simplifies the bremsstrahlung shielding design for the beamline transport. It also allows one to have a system for multibeamline branching and switching. More generally, a mirror is used for beam focusing and/or low-pass filtering. Six different mirror mounts have been designed for the SRI-CAT beamlines. Four of them are designed as water-cooled mirrors for white or pink beam use, and the other two are for monochromatic beam use. Mirror mount designs, including vacuum vessel structure and precision supporting stages, are presented in this paper.

  5. Advanced X-Ray Telescope Mirrors Provide Sharpest Focus Ever

    NASA Astrophysics Data System (ADS)

    1997-03-01

    Performing beyond expectations, the high- resolution mirrors for NASA's most powerful orbiting X-ray telescope have successfully completed initial testing at Marshall Space Flight Center's X-ray Calibration Facility, Huntsville, AL. "We have the first ground test images ever generated by the telescope's mirror assembly, and they are as good as -- or better than -- expected," said Dr. Martin Weisskopf, Marshall's chief scientist for NASA's Advanced X-ray Astrophysics Facility (AXAF). The mirror assembly, four pairs of precisely shaped and aligned cylindrical mirrors, will form the heart of NASA's third great observatory. The X-ray telescope produces an image by directing incoming X-rays to detectors at a focal point some 30 feet beyond the telescope's mirrors. The greater the percentage of X-rays brought to focus and the smaller the size of the focal spot, the sharper the image. Tests show that on orbit, the mirror assembly of the Advanced X-ray Astrophysics Facility will be able to focus approximately 70 percent of X-rays from a source to a spot less than one-half arc second in radius. The telescope's resolution is equivalent to being able to read the text of a newspaper from half a mile away. "The telescope's focus is very clear, very sharp," said Weisskopf. "It will be able to show us details of very distant sources that we know are out there, but haven't been able to see clearly." In comparison, previous X-ray telescopes -- Einstein and Rosat -- were only capable of focusing X- rays to five arc seconds. The Advanced X-ray Telescope's resolving power is ten times greater. "Images from the new telescope will allow us to make major advances toward understanding how exploding stars create and disperse many of the elements necessary for new solar systems and for life itself," said Dr. Harvey Tananbaum, director of the Advanced X- ray Astrophysics Facility Science Center at the Smithsonian Astrophysical Observatory, in Cambridge, MA -- responsible for the telescope

  6. Integration of Mirror Design with Suspension System using NASA's New Mirror Modeling Software

    NASA Technical Reports Server (NTRS)

    Arnold, William; Bevan Ryan M.; Stahl, Philip

    2013-01-01

    Advances in mirror fabrication is making very large space based telescopes possible. In the many applications, only monolithic mirrors meet the performance requirements. The existing and near-term planned heavy launch vehicles place a premium on lowest possible mass. Again, available and planned payload shroud size limits near term designs to 4 meter class mirror. Practical 8 meter and beyond designs could encourage planners to include larger shrouds if it can be proven that such mirrors can be manufactured. These two factors lower mass and larger mirrors, presents the classic optimization problem. There is a practical upper limit to how large a mirror can be supported by a purely kinematic mount system and be launched. This paper shows how the design of the suspension system and mirror blank needs to be designed simultaneously. We will also explore the concepts of auxiliary support systems, which act only during launch and disengage on orbit. We will define required characteristics of these systems and show how they can substantially reduce the mirror mass. The AMTD project is developing and maturing the processes for future replacements for HUBBLE, creating the design tools, validating the methods and techniques necessary to manufacture, test and launch extremely large optical missions. This paper will use the AMTD 4 meter "design point" as an illustration of the typical use of the modeler in generating the multiple models of mirror and suspension systems used during the conceptual design phase of most projects. The influence of Hexapod geometry, mirror depth, cell size and construction techniques (Exelsis Deep Core Low Temperature Fusion (c) versus Corning Frit Bonded (c) versus Schott Pocket Milled Zerodur (c) in this particular study) are being evaluated. Due to space and time consideration we will only be able to present snippets of the study in this paper. The advances in manufacturing techniques for lightweight mirrors, such as EXELSIS deep core low

  7. Advances in very lightweight composite mirror technology

    NASA Astrophysics Data System (ADS)

    Chen, Peter C.; Bowers, Charles W.; Content, David A.; Marzouk, Marzouk; Romeo, Robert C.

    2000-09-01

    We report progress in the development of very lightweight (< 5 kg/m2) mirrors made by replication using graphite fiber cyanate ester resin composites. The replication process is optimized to significantly improve the surface smoothness and figure quality. Achievements include near- diffraction-limited optical performance [< 1/20 wave root mean square (rms) at 632.8 nm] in replica flats, fractional wave rms performance in curved mirrors at 90% pupil, and almost exact reproduction of the surface microroughness of the mandrel. The curved mirrors typically show some edge roll off and several waves (rms optical) of astigmatism, coma, and third-order spherical aberration. These are indications of thermal contraction in an inhomogeneous medium. This inhomogeneity is due to a systematic radial variation in density and fiber/resin ratio induced in composite plies when draped around a small and highly curved mandrel. The figure accuracy is expected to improve with larger size optics and in mirrors with longer radii of curvature. Nevertheless, the present accuracy figure is sufficient for using postfiguring techniques such as ion milling to achieve diffraction-limited performances at optical and UV wavelengths. We demonstrate active figure control using a simple apparatus of low-mass, low-force actuators to correct astigmatism. The optimized replication technique is applied to the fabrication of a 0.6-m-diam mirror with an areal density of 3.2 kg/m2. Our result demonstrates that the very lightweight, large-aperture construction used in radio telescopes can now be applied to optical telescopes.

  8. Advanced Mirror Technology Development (AMTD) Thermal Trade Studies

    NASA Technical Reports Server (NTRS)

    Brooks, Thomas

    2015-01-01

    Advanced Mirror Technology Development (AMTD) is being done at Marshall Space Flight Center (MSFC) in preparation for the next large aperture UVOIR space observatory. A key science mission of that observatory is the detection and characterization of 'Earth-like' exoplanets. Direct exoplanet observation requires a telescope to see a planet which will be 10(exp -10) times dimmer than its host star. To accomplish this using an internal coronagraph requires a telescope with an ultra-stable wavefront error (WFE). This paper investigates parametric relationships between primary mirror physical parameters and thermal WFE stability. Candidate mirrors are designed as a mesh and placed into a thermal analysis model to determine the temperature distribution in the mirror when it is placed inside of an actively controlled cylindrical shroud at Lagrange point 2. Thermal strains resulting from the temperature distribution are found and an estimation of WFE is found to characterize the effect that thermal inputs have on the optical quality of the mirror. This process is repeated for several mirror material properties, material types, and mirror designs to determine how to design a mirror for thermal stability.

  9. Advanced Mirror Technology Development (AMTD) Project: Overview and Year 4 Accomplishments

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2016-01-01

    The Advanced Mirror Technology Development (AMTD) project is in Phase 2 of a multiyear effort initiated in Fiscal Year (FY) 2012, to mature toward the next Technology Readiness Level (TRL) critical technologies required to enable 4-m-or-larger monolithic or segmented ultraviolet, optical, and infrared (UVOIR) space telescope primary-mirror assemblies for general astrophysics and ultra-high-contrast observations of exoplanets. Key hardware accomplishments of 2015/16 are the successful low-temperature fusion of a 1.5-meter diameter ULE mirror that is a 1/3rd scale model of a 4-meter mirror and the initiation of polishing of a 1.2-meter Extreme-Lightweight Zerodur mirror. Critical to AMTD's success is an integrated team of scientists, systems engineers, and technologists; and a science-driven systems engineering approach.

  10. First mirrors for diagnostic systems of ITER

    NASA Astrophysics Data System (ADS)

    Litnovsky, A.; Voitsenya, V. S.; Costley, A.; Donné, A. J. H.; SWG on First Mirrors of the ITPA Topical Group on Diagnostics

    2007-08-01

    The majority of optical diagnostics presently foreseen for ITER will implement in-vessel metallic mirrors as plasma-viewing components. Mirrors are used for the observation of the plasma radiation in a very wide wavelength range: from about 1 nm up to a few mm. In the hostile ITER environment, mirrors are subject to erosion, deposition, particle implantation and other adverse effects which will change their optical properties, affecting the entire performance of the respective diagnostic systems. The Specialists Working Group (SWG) on first mirrors was established under the wings of the International Tokamak Physics Activity (ITPA) Topical Group (TG) on Diagnostics to coordinate and guide the investigations on diagnostic mirrors towards the development of optimal, robust and durable solutions for ITER diagnostic systems. The results of tests of various ITER-candidate mirror materials, performed in Tore-Supra, TEXTOR, DIII-D, TCV, T-10, TRIAM-1M and LHD under various plasma conditions, as well as an overview of laboratory investigations of mirror performance and mirror cleaning techniques are presented in the paper. The current tasks in the R&D of diagnostic mirrors will be addressed.

  11. Physics issues in mirror and tandem mirror systems

    SciTech Connect

    Post, R.F.

    1984-06-15

    Over the years the study of the confinement of high temperature plasma in magnetic mirror systems has presented researchers with many unusual physics problems. Many of these issues are by now understood theoretically and documented experimentally. With the advent of the tandem mirror idea, some new issues have emerged and are now under intensive study. These include: (1) the generation and control of ambipolar confining potentials and their effect on axial confinement and, (2) the combined influence of nonaxisymmetric magnetic fields (used to ensure MHD stability) and electric magnetic particle drifts on radial transport. Physics considerations associated with these two categories of issues will be reviewed, including concepts for the control of radial transport, under study or proposed.

  12. Segmented mirror control system hardware for CELT

    NASA Astrophysics Data System (ADS)

    Mast, Terry S.; Nelson, Jerry E.

    2000-07-01

    The primary mirror of the proposed California Extremely Large Telescope is a 30-meter diameter mosaic of hexagonal segments. The primary mirror active control will be achieved using four systems: sensors, actuators, processor, and alignment camera. We describe here the basic requirements of sensors and actuators, sketch a sensor design, and indicate interesting actuator alternatives.

  13. Optimization of the ATST primary mirror support system

    NASA Astrophysics Data System (ADS)

    Cho, Myung K.; Price, Ronald S.; Moon, Il K.

    2006-06-01

    The Advanced Technology Solar Telescope (ATST) primary mirror is a 4.24-m diameter, 75-mm thick, off-axis parabola solid meniscus mirror made out of a glass or glass ceramic material. Its baseline support system consists of 120 axial supports mounted at the mirror back surface and 24 lateral supports along the outer edge with an active optics capability. This primary mirror support system was optimized for the telescope at a near horizon position to achieve the best gravity and thermal effects. To fulfill the optical and mechanical performance requirements, extensive finite element analyses using I-DEAS and optical analyses with PCFRINGE have been conducted for the support optimization. Analyses include static deformation (gravity and thermal), frequency calculations, and support system sensitivity evaluations. An influence matrix was established to compensate potential errors using an active optics system. Performances of the primary mirror support system were evaluated from mechanical deformation calculations and the optical analyses before and after active optics corrections. The performance of the mirror cell structure was also discussed.

  14. Mirror neurons and mirror systems in monkeys and humans.

    PubMed

    Fabbri-Destro, Maddalena; Rizzolatti, Giacomo

    2008-06-01

    Mirror neurons are a distinct class of neurons that transform specific sensory information into a motor format. Mirror neurons have been originally discovered in the premotor and parietal cortex of the monkey. Subsequent neurophysiological (TMS, EEG, MEG) and brain imaging studies have shown that a mirror mechanism is also present in humans. According to its anatomical locations, mirror mechanism plays a role in action and intention understanding, imitation, speech, and emotion feeling.

  15. Advanced Dispersed Fringe Sensing Algorithm for Coarse Phasing Segmented Mirror Telescopes

    NASA Technical Reports Server (NTRS)

    Spechler, Joshua A.; Hoppe, Daniel J.; Sigrist, Norbert; Shi, Fang; Seo, Byoung-Joon; Bikkannavar, Siddarayappa A.

    2013-01-01

    Segment mirror phasing, a critical step of segment mirror alignment, requires the ability to sense and correct the relative pistons between segments from up to a few hundred microns to a fraction of wavelength in order to bring the mirror system to its full diffraction capability. When sampling the aperture of a telescope, using auto-collimating flats (ACFs) is more economical. The performance of a telescope with a segmented primary mirror strongly depends on how well those primary mirror segments can be phased. One such process to phase primary mirror segments in the axial piston direction is dispersed fringe sensing (DFS). DFS technology can be used to co-phase the ACFs. DFS is essentially a signal fitting and processing operation. It is an elegant method of coarse phasing segmented mirrors. DFS performance accuracy is dependent upon careful calibration of the system as well as other factors such as internal optical alignment, system wavefront errors, and detector quality. Novel improvements to the algorithm have led to substantial enhancements in DFS performance. The Advanced Dispersed Fringe Sensing (ADFS) Algorithm is designed to reduce the sensitivity to calibration errors by determining the optimal fringe extraction line. Applying an angular extraction line dithering procedure and combining this dithering process with an error function while minimizing the phase term of the fitted signal, defines in essence the ADFS algorithm.

  16. Advanced Mirror Technology Development (AMTD) Thermal Trade Studies

    NASA Technical Reports Server (NTRS)

    Brooks, Thomas; Stahl, Phil; Arnold, Bill

    2015-01-01

    Advanced Mirror Technology Development (AMTD) is being done at Marshall Space Flight Center (MSFC) in preparation for the next Ultraviolet, Optical, Infrared (UVOIR) space observatory. A likely science mission of that observatory is the detection and characterization of 'Earth-like' exoplanets. Direct exoplanet observation requires a telescope to see a planet that is 10-10 times dimmer than its host star. To accomplish this using an internal coronagraph requires a telescope with an ultra-stable wavefront. This paper investigates two topics: 1) parametric relationships between a primary mirror's thermal parameters and wavefront stability, and 2) optimal temperature profiles in the telescope's shroud and heater plate that minimize static wavefront error (WFE) in the primary mirror.

  17. Tandem Mirror Reactor Systems Code (Version I)

    SciTech Connect

    Reid, R.L.; Finn, P.A.; Gohar, M.Y.; Barrett, R.J.; Gorker, G.E.; Spampinaton, P.T.; Bulmer, R.H.; Dorn, D.W.; Perkins, L.J.; Ghose, S.

    1985-09-01

    A computer code was developed to model a Tandem Mirror Reactor. Ths is the first Tandem Mirror Reactor model to couple, in detail, the highly linked physics, magnetics, and neutronic analysis into a single code. This report describes the code architecture, provides a summary description of the modules comprising the code, and includes an example execution of the Tandem Mirror Reactor Systems Code. Results from this code for two sensitivity studies are also included. These studies are: (1) to determine the impact of center cell plasma radius, length, and ion temperature on reactor cost and performance at constant fusion power; and (2) to determine the impact of reactor power level on cost.

  18. Adaptive PVDF piezoelectric deformable mirror system.

    PubMed

    Sato, T; Ishida, H; Ikeda, O

    1980-05-01

    An adaptive mirror system whose surface deforms smoothly according to the desired curve has been made of polyvinylidene fluoride (PVDF) piezoelectric film and laminar glass plate. One surface of the glass plate was evaporated with silver, and this side was used as the mirror surface. A PVDF film, whose shape was determined by the deformation curve, was pasted tightly on the other surface. The mirror deforms smoothly along this curve with the application of a single voltage to the film. Holographic filter and feedback were lso considered to improve the static and dynamic characteristics. Typically, deformation along ax(2)+bx(3) was obtained. PMID:20221054

  19. Mirror Advanced Reactor Study (MARS): executive summary and overview

    SciTech Connect

    Logan, B.G.; Perkins, L.J.; Gordon, J.D.

    1984-07-01

    Two self-consistent MARS configurations are discussed - a 1200-MWe commercial electricity-generating plant and a synguels-generating plant that produces hydrogen with an energy equivalent to 26,000 barrels of oil per day. The MARS machine emphasizes the attractive features of the tandem mirror concept, including steady-state operation, a small-diameter high-beta plasma, a linear central cell with simple low-maintenance blankets, low first-wall heat fluxes (<10 W/cm/sup 2/), no driven plasma currents or associated disruptions, natural halo impurity diversion, and direct conversion of end-loss charged-particle power. The MARS electric plant produces 2600 MW of fusion power in a 130-m-long central cell. Advanced tandem-mirror plasma-engineering concepts, a high-efficiency liquid lithium-lead (Li/sub 17/Pb/sub 83/) blanket, and efficient direct electrical conversion of end loss power combine to produce a high net plant efficiency of 36%. With a total capital cost of $2.9 billion (constant 1983 dollars), the MARS electric plant produces busbar electricity at approx. 7 cents/kW-hour. The MARS synfuels plant produces 3500 MW of fusion power in a 150-m-long central cell. A helium-gas-cooled silicon carbide pebble-bed blanket provides high-temperature (1000/sup 0/C) heat to a thermochemical water-splitting cycle and the resulting hydrogen is catalytically converted to methanol for distribution. With a total capital cost of $3.6 billion (constant 1983 dollars), the synfuels plant produces methanol fuel at about $1.7/gal. The major features of the MARS reactor include sloshing-ion thermal barrier plugs for efficient plasma confinement, a high efficiency blanket, high-field (24-T) choke cells, drift pumping for trapped plasma species, quasi-optical electron-cyclotron resonant heating (ECRH) systems, and a component gridless direct converter.

  20. Mirror Fusion Test Facility magnet system

    SciTech Connect

    VanSant, J.H.; Kozman, T.A.; Bulmer, R.H.; Ng, D.S.

    1981-09-11

    In 1979, R.H. Bulmer of Lawrence Livermore National Laboratory (LLNL) discussed a proposed tandem-mirror magnet system for the Mirror Fusion Test Facility (MFTF) at the 8th symposium on Engineering Problems in Fusion Research. Since then, Congress has voted funds for expanding LLNL's MFTF to a tandem-mirror facility (designated MFTF-B). The new facility, scheduled for completion by 1985, will seek to achieve two goals: (1) Energy break-even capability (Q or the ratio of fusion energy to plasma heating energy = 1) of mirror fusion, (2) Engineering feasibility of reactor-scale machines. Briefly stated, 22 superconducting magnets contained in a 11-m-diam by 65-m-long vacuum vessel will confine a fusion plasma fueled by 80 axial streaming-plasma guns and over 40 radial neutral beams. We have already completed a preliminary design of this magnet system.

  1. Single-layer mirrors for advanced research light sources

    SciTech Connect

    Stoermer, M.; Horstmann, C.; Siewert, F.; Hertlein, F.; Matiaske, M.; Wiesmann, J.; Gaudin, J.

    2010-06-23

    X-ray mirrors are needed for beam guidance, beam alignment and monochromatisation at third-generation synchrotron light sources (PETRA III) and forthcoming Free-Electron Lasers (LCLS, European XFEL). Amorphous carbon coatings are currently used as total reflection mirrors at FLASH to guide the photon beam to the various beamlines. These coatings were prepared by means of magnetron sputtering. The new GKSS sputtering facility for the deposition of single and multilayer mirrors with a length of up to 1500 mm and a width of up to 120 mm is in operation. In this contribution we present the results of this new deposition system. A major advantage is that it is now possible to prepare one, two or more mirrors with similar properties over the whole deposition length. The mirror properties were investigated by means of X-ray reflectometry and interference microscopy. The performance of the mirrors is analyzed, considering X-ray reflectivity, film thickness and surface roughness. The uniformity of these properties over the whole deposition length of 1500 mm is demonstrated. The results obtained will be discussed and compared with former results.

  2. AMTD: Advanced Mirror Technology Development in mechanical stability

    NASA Astrophysics Data System (ADS)

    Knight, J. B.

    2015-09-01

    Analytical tools and processes are being developed at NASA Marshal Space Flight Center in support of the Advanced Mirror Technology Development (AMTD) project. One facet of optical performance is mechanical stability with respect to structural dynamics. Pertinent parameters are: (1) the spacecraft structural design, (2) the mechanical disturbances on-board the spacecraft (sources of vibratory/transient motion such as reaction wheels), (3) the vibration isolation systems (invariably required to meet future science needs), and (4) the dynamic characteristics of the optical system itself. With stability requirements of future large aperture space telescopes being in the lower Pico meter regime, it is paramount that all sources of mechanical excitation be considered in both feasibility studies and detailed analyses. The primary objective of this paper is to lay out a path to perform feasibility studies of future large aperture space telescope projects which require extreme stability. To get to that end, a high level overview of a structural dynamic analysis process to assess an integrated spacecraft and optical system is included.

  3. AMTD - Advanced Mirror Technology Development in Mechanical Stability

    NASA Technical Reports Server (NTRS)

    Knight, J. Brent

    2015-01-01

    Analytical tools and processes are being developed at NASA Marshal Space Flight Center in support of the Advanced Mirror Technology Development (AMTD) project. One facet of optical performance is mechanical stability with respect to structural dynamics. Pertinent parameters are: (1) the spacecraft structural design, (2) the mechanical disturbances on-board the spacecraft (sources of vibratory/transient motion such as reaction wheels), (3) the vibration isolation systems (invariably required to meet future science needs), and (4) the dynamic characteristics of the optical system itself. With stability requirements of future large aperture space telescopes being in the lower Pico meter regime, it is paramount that all sources of mechanical excitation be considered in both feasibility studies and detailed analyses. The primary objective of this paper is to lay out a path to perform feasibility studies of future large aperture space telescope projects which require extreme stability. To get to that end, a high level overview of a structural dynamic analysis process to assess an integrated spacecraft and optical system is included.

  4. Thermal analysis of the Advanced Technology Large Aperture Space Telescope (ATLAST) 8-meter primary mirror

    NASA Astrophysics Data System (ADS)

    Hornsby, Linda; Hopkins, Randall C.; Stahl, H. Philip

    2010-07-01

    The Advanced Technology Large Aperture Space Telescope (ATLAST) preliminary design concept consists of an 8 meter diameter monolithic primary mirror enclosed in an insulated, optical tube with stray light baffles and a sunshade. ATLAST will be placed in orbit about the Sun-Earth L2 point and will experience constant exposure to the sun. The insulation on the optical tube and sunshade serve to cold bias the telescope which helps to minimize thermal gradients. The objective is to maintain the primary mirror at 280K with an active thermal control system. The geometric model of the primary mirror, optical tube, sun baffles, and sunshade was developed using Thermal Desktop®1. A detailed model of the primary mirror was required in order to characterize the static performance and thermal stability of the mirror during maneuvers. This is important because long exposure observations, such as extra-solar terrestrial planet finding and characterization, require a very stable observatory wave front. Steady state thermal analyses served to predict mirror temperatures for several different sun angles. Transient analyses were performed in order to predict thermal time constant of the primary mirror for a 20 degree slew and a 30 degree roll maneuver. This paper describes the thermal model and provides details of the geometry, thermo-optical properties, and the solar environment that influences the thermal performance. All assumptions that were used in the analysis are also documented. Estimates of mirror heater power requirements are reported. The thermal model is used to predict gradients across and through the primary mirror using an idealized boundary temperature on the back and sides of the mirror of 280 K.

  5. The VST active primary mirror support system

    NASA Astrophysics Data System (ADS)

    Schipani, Pietro; Capaccioli, Massimo; D'Orsi, Sergio; Ferragina, Luigi; Marty, Laurent; Molfese, Cesare; Perrotta, Francesco; De Paris, Giacinto; Fierro, Davide; Tomelleri, Raffaele; Rossettini, Pierfrancesco; Perina, Francesco; Recchia, Stefano; Magrin, Demetrio

    2010-07-01

    The 2.6-m primary mirror of the VST telescope is equipped with an active optics system in order to correct low-order aberrations, constantly monitoring the optical quality of the image and controlling the relative position and the shape of the optical elements. Periodically an image analyser calculates the deviation of the image from the best quality. VST is equipped with both a Shack-Hartmann in the probe system and a curvature sensor embedded in the OmegaCAM instrument. The telescope control software decomposes the deviation into single optical contributions and calculates the force correction that each active element has to perform to achieve the optimal quality. The set of correction forces, one for each axial actuator, is computed by the telescope central computer and transmitted to the local control unit of the primary mirror system for execution. The most important element of the VST active optics is the primary mirror, with its active support system located within the primary mirror cell structure. The primary mirror support system is composed by an axial and a lateral independent systems and includes an earthquake safety system. The system is described and the results of the qualification test campaign are discussed.

  6. Advanced UVOIR Mirror Technology Development for Very Large Space Telescopes

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2011-01-01

    Objective of this work is to define and initiate a long-term program to mature six inter-linked critical technologies for future UVOIR space telescope mirrors to TRL6 by 2018 so that a viable flight mission can be proposed to the 2020 Decadal Review. (1) Large-Aperture, Low Areal Density, High Stiffness Mirrors: 4 to 8 m monolithic & 8 to 16 m segmented primary mirrors require larger, thicker, stiffer substrates. (2) Support System:Large-aperture mirrors require large support systems to ensure that they survive launch and deploy on orbit in a stress-free and undistorted shape. (3) Mid/High Spatial Frequency Figure Error:A very smooth mirror is critical for producing a high-quality point spread function (PSF) for high-contrast imaging. (4) Segment Edges:Edges impact PSF for high-contrast imaging applications, contributes to stray light noise, and affects the total collecting aperture. (5) Segment-to-Segment Gap Phasing:Segment phasing is critical for producing a high-quality temporally stable PSF. (6) Integrated Model Validation:On-orbit performance is determined by mechanical and thermal stability. Future systems require validated performance models. We are pursuing multiple design paths give the science community the option to enable either a future monolithic or segmented space telescope.

  7. Distributed control system for active mirrors

    NASA Astrophysics Data System (ADS)

    Rodriguez-Ramos, Luis F.; Williams, Mark R.; Castro, Javier; Cruz, A.; Gonzalez, Juan C.; Mack, Brian; Martin, Carlos; Pescador, German; Sanchez, Vicente; Sosa, Nicolas A.

    1994-06-01

    This paper presents the IAC (Instituto de Astrofisica de Canaries, Spain) proposal of a distributed control system intended for the active support of a 8 m mirror. The system incorporates a large number of compact `smart' force actuators, six force definers, and a mirror support computer (MSC) for interfacing with the telescope control system and for general housekeeping. We propose the use of a network for the interconnection of the actuators, definers and the MSC, which will minimize the physical complexity of the interface between the mirror support system and the MSC. The force actuator control electronics are described in detail, as is the system software architecture of the actuator and the MSC. As the network is a key point for the system, we also detail the evaluation of three candidates, before electing the CAN bus.

  8. Thermal Analysis of the Advanced Technology Large Aperture Space Telescope (ATLAST) 8 Meter Primary Mirror

    NASA Technical Reports Server (NTRS)

    Hornsby, Linda; Stahl, H. Philip; Hopkins, Randall C.

    2010-01-01

    The Advanced Technology Large Aperture Space Telescope (ATLAST) preliminary design concept consists of an 8 meter diameter monolithic primary mirror enclosed in an insulated, optical tube with stray light baffles and a sunshade. ATLAST will be placed in orbit about the Sun-Earth L2 and will experience constant exposure to the sun. The insulation on the optical tube and sunshade serve to cold bias the telescope which helps to minimize thermal gradients. The primary mirror will be maintained at 280K with an active thermal control system. The geometric model of the primary mirror, optical tube, sun baffles, and sunshade was developed using Thermal Desktop(R) SINDA/FLUINT(R) was used for the thermal analysis and the radiation environment was analyzed using RADCAD(R). A XX node model was executed in order to characterize the static performance and thermal stability of the mirror during maneuvers. This is important because long exposure observations, such as extra-solar terrestrial planet finding and characterization, require a very stable observatory wave front. Steady state thermal analyses served to predict mirror temperatures for several different sun angles. Transient analyses were performed in order to predict thermal time constant of the primary mirror for a 20 degree slew or 30 degree roll maneuver. This paper describes the thermal model and provides details of the geometry, thermo-optical properties, and the environment which influences the thermal performance. All assumptions that were used in the analysis are also documented. Parametric analyses are summarized for design parameters including primary mirror coatings and sunshade configuration. Estimates of mirror heater power requirements are reported. The thermal model demonstrates results for the primary mirror heated from the back side and edges using a heater system with multiple independently controlled zones.

  9. Advanced Mirror Technology Development (AMTD) Project: 3.0 Year Status

    NASA Astrophysics Data System (ADS)

    Stahl, H. Philip

    2015-01-01

    Advanced Mirror Technology Development (AMTD) is a funded NASA Strategic Astrophysics Technology project. Begun in 2011, we are in Phase 2 of a multi-year effort. Our objective is to mature towards TRL6 critical technologies needed to produce 4-m or larger flight-qualified UVOIR mirrors by 2018 so that a viable astronomy mission can be considered by the 2020 Decadal Review. The developed technology must enable missions capable of both general astrophysics and ultra-high contrast observations of exoplanets. Just as JWST's architecture was driven by launch vehicle, a future UVOIR mission's architecture (monolithic, segmented or interferometric) will depend on capacities of future launch vehicles (and budget). Since we cannot predict the future, we must prepare for all potential futures. Therefore, we are pursuing multiple technology paths. AMTD uses a science-driven systems engineering approach. We mature technologies required to enable the highest priority science AND result in a high-performance low-cost low-risk system. One of our key accomplishments is that we have derived engineering specifications for advanced normal-incidence monolithic and segmented mirror systems needed to enable both general astrophysics and ultra-high contrast observations of exoplanets missions as a function of potential launch vehicle and its inherent mass and volume constraints. Another key accomplishment is that we have matured our technology by building and testing hardware. To demonstrate stacked core technology, we built a 400 mm thick mirror. Currently, to demonstrate lateral scalability, we are manufacturing a 1.5 meter mirror. To assist in architecture trade studies, the Engineering team develops Structural, Thermal and Optical Performance (STOP) models of candidate mirror assembly systems including substrates, structures, and mechanisms. These models are validated by test of full- and subscale components in relevant thermo-vacuum environments. Specific analyses include: maximum

  10. Advanced mirror technology development (AMTD) project: 2.5 year status

    NASA Astrophysics Data System (ADS)

    Stahl, H. Philip; Postman, Marc; Abplanalp, Laura; Arnold, William; Blaurock, Carl; Egerman, Robert; Mosier, Gary

    2014-08-01

    The Advance Mirror Technology Development (AMTD) project is in Phase 2 of a multiyear effort, initiated in FY12, to mature by at least a half TRL step six critical technologies required to enable 4 meter or larger UVOIR space telescope primary mirror assemblies for both general astrophysics and ultra-high contrast observations of exoplanets. AMTD continues to achieve all of its goals and accomplished all of its milestones to date. We have done this by assembling an outstanding team from academia, industry, and government with extensive expertise in astrophysics and exoplanet characterization, and in the design/manufacture of monolithic and segmented space telescopes; by deriving engineering specifications for advanced normal-incidence mirror systems needed to make the required science measurements; and by defining and prioritizing the most important technical problems to be solved.

  11. Satellite mirror systems for providing terrestrial power - System concept

    NASA Technical Reports Server (NTRS)

    Billman, K. W.; Gilbreath, W. P.; Bowen, S. W.

    1978-01-01

    A system of orbiting reflectors, SOLARES, has been studied as a possible means of providing terrestrial power with a space system of minimum mass and complexity. The key impact that such a system, providing continuous and slightly concentrated insolation, makes on the economic viability of solar farming is demonstrated. New developments in solar sailing are incorporated to reduce mirror mass and transportation cost. The system is compatible with incremental implementation and continual expansion to produce the world's power needs. Key technology, environmental, and economic issues and payoffs are identified. SOLARES appears to be economically superior to other advanced, and even conventional, energy systems and could be scaled to completely abate our fossil fuel usage for power generation.

  12. Finite mirror effects in advanced interferometric gravitational wave detectors

    SciTech Connect

    Lundgren, Andrew P.; Bondarescu, Ruxandra; Tsang, David; Bondarescu, Mihai

    2008-02-15

    Thermal noise is expected to be the dominant source of noise in the most sensitive frequency band of second-generation, ground-based gravitational-wave detectors. Reshaping the beam to a flatter, wider profile which probes more of the mirror surface reduces this noise. The 'Mesa' beam shape has been proposed for this purpose and was subsequently generalized to a family of hyperboloidal beams with two parameters: twist angle {alpha} and beam width D. Varying {alpha} allows a continuous transition from the nearly flat ({alpha}=0) to the nearly concentric ({alpha}={pi}) Mesa beam configurations. We analytically prove that in the limit D{yields}{infinity} hyperboloidal beams become Gaussians. The ideal beam choice for reducing thermal noise is the widest possible beam that satisfies the Advanced LIGO (Laser Interferometer Gravitational-wave Observatory) diffraction loss design constraint of 1 part per million (ppm) per bounce for a mirror radius of 17 cm. In the past the diffraction loss has often been calculated using the clipping approximation that, in general, underestimates the diffraction loss. We develop a code using pseudospectral methods to compute the diffraction loss directly from the propagator. We find that the diffraction loss is not a strictly monotonic function of beam width, but has local minima that occur due to finite mirror effects and leads to natural choices of D. For an {alpha}={pi} Mesa beam a local minimum occurs at D=10.67 cm and leads to a diffraction loss of 1.4 ppm. We then compute the thermal noise for the entire hyperboloidal family. We find that if one requires a diffraction loss of strictly 1 ppm, the {alpha}=0.91{pi} hyperboloidal beam is optimal, leading to the coating thermal noise (the dominant source of noise for fused-silica mirrors) being lower by about 10% than for a Mesa beam while other types of thermal noise decrease as well. We then develop an iterative process that reconstructs the mirror to specifically account for finite

  13. Long Focal Length Large Mirror Fabrication System

    NASA Technical Reports Server (NTRS)

    Bennett, H. E.

    2003-01-01

    The goals of this ambitious program are (1) to develop systems to make large superpolished optical mirrors, (2) to develop low scatter polishing techniques using centrifugal elutriation, (3) to develop a means of measuring scatter at any point on the mirror, (4) to polish a Hindle sphere to measure the optical figure of a one meter diameter convex mandrel, and (5) to fabricate low scatter, large adaptive optic graphite filled, cyanate ester replica transfer mirrors using these mandrels. Deliverables are a 30 cm diameter superpolished composite AO mirror. We fabricated a 1/3rd meter superpolished zerodur flat mandrel and with the support of our major subcontractor, Composite Mirror Applications Inc (CMA) we have demonstrated a 30 cm lightweight cyanate ester mirror with an rms microroughness between 0.6 and 0.8 nm and 8 faceplate influence function of 5 cm. The influence function was chosen to be comparable to the atmospheric correlation coefficient r(sub 0) which is about 5 cm at sea level. There was no print-thru of the graphite fibers in the cyanate ester surface (the bane of many previous efforts to use cyanate ester mirrors). Our subcontractor has devised a means for developing a 30-50 nm thick layer of graphite free pure ester resin on the surface of the mirrors. This graphite fiber filled material has a thermal expansion coefficient in the 10(exp -8) centimeter per Kelvin range (the same range of expansion coefficient as Zerodur and ULE glasses) and does not take up water and swell, so it is a nearly ideal mirror material in these areas. Unfortunately for these 0.8mm thick faceplates, the number of plies is not enough to result in isometric coverage. Isolated figure irregularities can appear, making it necessary to go to thicker faceplates. The influence function will then only approximate the length of r(sub 0), at higher altitudes or longer wavelengths. The influence function goes as the cube of the thickness, so we are now making a faceplate optimized for

  14. Freeform mirror based optical systems for FAME

    NASA Astrophysics Data System (ADS)

    Agócs, Tibor; Kroes, Gabby; Venema, Lars; Hugot, Emmanuel; Schnetler, Hermine; Jaskó, Attila

    2014-07-01

    In this paper we present the design of freeform mirror based optical systems that have the potential to be used in future astronomical instrumentation in the era of extremely large ground based telescopes. Firstly we describe the optical requirements followed by a summary of the optimization methodology used to design the freeform surface. The intention is to create optical architectures, which not only have the numerous advantages of freeform based systems (increased optical performance and/or reduction of mass and volume), but also can be manufactured and tested with today's manufacturing techniques and technologies. The team plans to build a demonstrator based on one of the optical design examples presented in this paper. The demonstrator will be built and tested as part of the OPTICON FP7 Freeform Active Mirror Experiment (FAME) project. A hydroforming technique developed as part of the previous OPTICON FP7 project will be used to produce an accurate, compact and stable freeform mirror. The manufacturing issues normally experienced in the production of freeform mirrors are solved through the hydroforming of thin polished substrates, which then will be supported with an active array structure. The active array will be used to compensate for residual manufacturing errors, thermo-elastic deformation and gravity-induced errors.

  15. Four-mirror extreme ultraviolet (EUV) lithography projection system

    DOEpatents

    Cohen, Simon J; Jeong, Hwan J; Shafer, David R

    2000-01-01

    The invention is directed to a four-mirror catoptric projection system for extreme ultraviolet (EUV) lithography to transfer a pattern from a reflective reticle to a wafer substrate. In order along the light path followed by light from the reticle to the wafer substrate, the system includes a dominantly hyperbolic convex mirror, a dominantly elliptical concave mirror, spherical convex mirror, and spherical concave mirror. The reticle and wafer substrate are positioned along the system's optical axis on opposite sides of the mirrors. The hyperbolic and elliptical mirrors are positioned on the same side of the system's optical axis as the reticle, and are relatively large in diameter as they are positioned on the high magnification side of the system. The hyperbolic and elliptical mirrors are relatively far off the optical axis and hence they have significant aspherical components in their curvatures. The convex spherical mirror is positioned on the optical axis, and has a substantially or perfectly spherical shape. The spherical concave mirror is positioned substantially on the opposite side of the optical axis from the hyperbolic and elliptical mirrors. Because it is positioned off-axis to a degree, the spherical concave mirror has some asphericity to counter aberrations. The spherical concave mirror forms a relatively large, uniform field on the wafer substrate. The mirrors can be tilted or decentered slightly to achieve further increase in the field size.

  16. Active Beam Shaping System and Method Using Sequential Deformable Mirrors

    NASA Technical Reports Server (NTRS)

    Norman, Colin A. (Inventor); Pueyo, Laurent A. (Inventor)

    2015-01-01

    An active optical beam shaping system includes a first deformable mirror arranged to at least partially intercept an entrance beam of light and to provide a first reflected beam of light, a second deformable mirror arranged to at least partially intercept the first reflected beam of light from the first deformable mirror and to provide a second reflected beam of light, and a signal processing and control system configured to communicate with the first and second deformable mirrors. The first deformable mirror, the second deformable mirror and the signal processing and control system together provide a large amplitude light modulation range to provide an actively shaped optical beam.

  17. Modeling control systems for primary mirror supports

    NASA Astrophysics Data System (ADS)

    Fisher, Martin; Haque, Jaque; Wilkes, John D.; Amos, Clive S.; Steel, Darrin J.

    1995-06-01

    The RGO is involved in a number of mirror support programs, ranging from new controllers for its existing Isaac Newton Group (ING) telescopes to new primary mirror supports for the UK Infra-red Telescope (UKIRT) and design proposals for the active support of the Gemini 8 m meniscus mirrors. This work has led to the identification or development of critical components such as load cells and control valves which have high precision and stability. Even so it is still necessary to develop servo controllers capable of minimizing the effects of non- linearity and maintaining stability, particularly in regard to the highly non-linear behavior of pneumatic supports. In order to predict the performance of mirror supports and compare differing control strategies, components and systems are modelled using Matlab(superscript R) and Simulink(superscript R). These models are presented, together with parameters derived experimentally, and results from recent laboratory tests are discussed. Specific applications are described and current status of the work at the time of submission is presented.

  18. FOXP2 and the mirror system.

    PubMed

    Corballis, Michael C

    2004-03-01

    An inherited deficit in spoken language has been associated with a mutation in the forkhead box P2 (FOXP2) gene on chromosome 7. A recent functional magnetic resonance imaging study has linked the deficit to underactivity in Broca's area during word generation, which in turn suggests a possible link between FOXP2 and the mirror-neuron system observed in the primate homologue of Broca's area. This link might have implications for the evolution of Broca's area and its role in speech.

  19. Overview and Summary of Advanced UVOIR Mirror Technology Development (AMTD) Project

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2014-01-01

    ASTRO2010 Decadal Survey stated that an advanced large-aperture ultraviolet, optical, near-infrared (UVOIR) telescope is required to enable the next generation of compelling astrophysics and exoplanet science; and, that present technology is not mature enough to affordably build and launch any potential UVOIR mission concept. AMTD is a multiyear effort to develop, demonstrate and mature critical technologies to TRL-6 by 2018 so that a viable flight mission can be proposed to the 2020 Decadal Review. AMTD builds on the state of art (SOA) defined by over 30 years of monolithic & segmented ground & space-telescope mirror technology to mature six key technologies: center dotLarge-Aperture, Low Areal Density, High Stiffness Mirror Substrates: Both (4 to 8 m) monolithic and (8 to 16 m) segmented telescopes require larger and stiffer mirrors. center dotSupport System: Large-aperture mirrors require large support systems to ensure that they survive launch, deploy on orbit, and maintain a stable, undistorted shape. center dotMid/High Spatial Frequency Figure Error: Very smooth mirror is critical for producing high-quality point spread function (PSF) for high contrast imaging. center dotSegment Edges: The quality of segment edges impacts PSF for high-contrast imaging applications, contributes to stray light noise, and affects total collecting aperture. center dotSegment to Segment Gap Phasing: Segment phasing is critical for producing high-quality temporally-stable PSF. center dotIntegrated Model Validation: On-orbit performance is driven by mechanical & thermal stability. Compliance cannot be 100% tested, but relies on modeling. Because we cannot predict the future, AMTD is pursuing multiple design paths to provide the science community with options to enable either large aperture monolithic or segmented mirrors with clear engineering metrics traceable to science requirements

  20. Advanced UVOIR Mirror Technology Development (AMTD) for Very Large Space Telescopes

    NASA Technical Reports Server (NTRS)

    Postman, Marc; Soummer, Remi; Sivramakrishnan, Annand; Macintosh, Bruce; Guyon, Olivier; Krist, John; Stahl, H. Philip; Smith, W. Scott; Mosier, Gary; Kirk, Charles; Arnold, William

    2013-01-01

    ASTRO2010 Decadal Survey stated that an advanced large-aperture ultraviolet, optical, near-infrared (UVOIR) telescope is required to enable the next generation of compelling astrophysics and exoplanet science; and, that present technology is not mature enough to affordably build and launch any potential UVOIR mission concept. AMTD is the start of a multiyear effort to develop, demonstrate and mature critical technologies to TRL-6 by 2018 so that a viable flight mission can be proposed to the 2020 Decadal Review. AMTD builds on the state of art (SOA) defined by over 30 years of monolithic & segmented ground & space-telescope mirror technology to mature six key technologies: (1) Large-Aperture, Low Areal Density, High Stiffness Mirror Substrates: Both (4 to 8 m) monolithic and (8 to 16 m) segmented primary mirrors require larger, thicker, and stiffer substrates. (2) Support System: Large-aperture mirrors require large support systems to ensure that they survive launch and deploy on orbit in a stress-free and undistorted shape. (3) Mid/High Spatial Frequency Figure Error: Very smooth mirror is critical for producing high-quality point spread function (PSF) for high contrast imaging. (4) Segment Edges: The quality of segment edges impacts PSF for high-contrast imaging applications, contributes to stray light noise, and affects total collecting aperture. (5) Segment to Segment Gap Phasing: Segment phasing is critical for producing high-quality temporally-stable PSF. (6) Integrated Model Validation: On-orbit performance is driven by mechanical & thermal stability. Compliance cannot be 100% tested, but relies on modeling. AMTD is pursuing multiple design paths to provide the science community with options to enable either large aperture monolithic or segmented mirrors with clear engineering metrics traceable to science requirements.

  1. Compact neutron imaging system using axisymmetric mirrors

    DOEpatents

    Khaykovich, Boris; Moncton, David E; Gubarev, Mikhail V; Ramsey, Brian D; Engelhaupt, Darell E

    2014-05-27

    A dispersed release of neutrons is generated from a source. A portion of this dispersed neutron release is reflected by surfaces of a plurality of nested, axisymmetric mirrors in at least an inner mirror layer and an outer mirror layer, wherein the neutrons reflected by the inner mirror layer are incident on at least one mirror surface of the inner mirror layer N times, wherein N is an integer, and wherein neutrons reflected by the outer mirror are incident on a plurality of mirror surfaces of the outer layer N+i times, where i is a positive integer, to redirect the neutrons toward a target. The mirrors can be formed by a periodically reversed pulsed-plating process.

  2. "Pocket" Deformable Mirror for an Integrated On-Mirror Adaptive System

    NASA Astrophysics Data System (ADS)

    Beresnev, L.; Voronstov, M.; Wangsness, P.

    Existing HEL beam control architectures are extremely complicated because they require installation and alignment of a large number of optical elements, resulting in substantial increase of the entire HEL system size, weight and cost. There is a strong interest in designing new robust beam control capabilities integrated directly to a beam director system. The discussed technical effort is focused on development and demonstration of a new adaptive beam director (ABD) consisting of a beam forming telescope with wavefront compensation integrated solely on its ultra-lightweight primary mirror. This on-mirror AO system will be controlled using a stochastic parallel gradient descent (SPGD) controller specifically designed for target-in-the-loop (TIL) operation. The key component of the on-mirror AO system is its primary mirror. This mirror contains an array of pockets machined on its backside, called a pocket-mirror. A special dielectric layer deposited on the front surface of the pocket-mirror is highly reflective for the HEL wavelength ???HEL, and semi-transparent for the laser illuminator wavelength ?ILL. Thus the wave ?ILL scattered by the target surface enters inside the mirror pockets, while the outgoing HEL beam with wavelength ?HEL is totally reflected. The pockets of the ABD pocket-mirror include opto-electronic components that can provide local (inside pocket-window) wavefront correction and sensing. Wavefront correction at each pocket aperture is performed using electrically sectioned piezo-ceramic annular rings made from thin (~0.3 mm) bimorph discs glued to the pocket bottoms. Control voltages applied to these electrodes result in mechanical deformation of the pocket-window front surface thus providing compensation of low-order aberrations at each pocket-window. Packaging the pockets with a high fill factor allows high resolution control of the beam director primary mirror shape. Preliminary analysis has shown that surface stroke near 3 microns with

  3. Magnetohydrodynamic Instabilities in a Simple Gasdynamic Mirror Propulsion System

    NASA Technical Reports Server (NTRS)

    Emrich, William J., Jr.; Hawk, Clark W.

    2004-01-01

    The gasdynamic mirror has been proposed as a concept which could form the basis of a highly efficient fusion rocket engine. Gasdynamic mirrors differ from most other mirror type plasma confinement schemes in that they have much larger aspect ratios and operate at somewhat higher plasma densities. To evaluate whether a gasdynamic mirror could indeed confine plasmas in a stable manner for long periods of time, a small scale experimental gasdynamic mirror was built and tested. The objective of this experiment was to determine ranges of mirror ratios and plasma densities over which gasdynamic mirror could maintain stable plasmas. Theoretical analyses indicated that plasma magnetohydrodynamic instabilities were likely to occur during subsonic to supersonic flow transitions in the mirror throat region of the gasdynamic mirror. The experimental evidence based upon data derived from the Langmuir probe measurements seems to confirm this analysis. The assumption that a gasdynamic mirror using a simple mirror geometry could be used as a propulsion system, therefore, appears questionable. Modifications to the simple mirror concept are presented which could mitigate these MHD instabilities.

  4. The primary mirror support system of the ESO-VLT.

    NASA Astrophysics Data System (ADS)

    Schneermann, M.; Cui, X.-Q.

    1988-10-01

    The 8 meter unit telescopes of the ESO very large telescope (VLT) will have primary mirrors of the solid thin meniscus type. Presently various different options concerning material and thickness are still under consideration for the production of the mirror blanks. This paper describes the performance analysis of a glass ceramic mirror with a thickness of 200 mm. This mirror is supported by a functionally separated axial and radial support system. The results of the analytical assessment of the mirror performance under those loading conditions are discussed.

  5. An experimental task to examine the mirror system in rats

    PubMed Central

    Takano, Yuji; Ukezono, Masatoshi

    2014-01-01

    The mirror system in the brain is considered to be a neural basis of sociality, but previous studies have been limited to primates. Here we report an experimental task to examine the mirror system in rats. We show that a rat could reach to a pellet and grasp and eat it in front of another rat that was observing the reaching, which indicates that the task will enable us to start exploring the rat mirror system. PMID:25323637

  6. An experimental task to examine the mirror system in rats.

    PubMed

    Takano, Yuji; Ukezono, Masatoshi

    2014-01-01

    The mirror system in the brain is considered to be a neural basis of sociality, but previous studies have been limited to primates. Here we report an experimental task to examine the mirror system in rats. We show that a rat could reach to a pellet and grasp and eat it in front of another rat that was observing the reaching, which indicates that the task will enable us to start exploring the rat mirror system. PMID:25323637

  7. Language comprehension warps the mirror neuron system.

    PubMed

    Zarr, Noah; Ferguson, Ryan; Glenberg, Arthur M

    2013-01-01

    Is the mirror neuron system (MNS) used in language understanding? According to embodied accounts of language comprehension, understanding sentences describing actions makes use of neural mechanisms of action control, including the MNS. Consequently, repeatedly comprehending sentences describing similar actions should induce adaptation of the MNS thereby warping its use in other cognitive processes such as action recognition and prediction. To test this prediction, participants read blocks of multiple sentences where each sentence in the block described transfer of objects in a direction away or toward the reader. Following each block, adaptation was measured by having participants predict the end-point of videotaped actions. The adapting sentences disrupted prediction of actions in the same direction, but (a) only for videos of biological motion, and (b) only when the effector implied by the language (e.g., the hand) matched the videos. These findings are signatures of the MNS.

  8. Parametric systems analysis for tandem mirror hybrids

    SciTech Connect

    Lee, J.D.; Chapin, D.L.; Chi, J.W.H.

    1980-09-01

    Fusion fission systems, consisting of fissile producing fusion hybrids combining a tandem mirror fusion driver with various blanket types and net fissile consuming LWR's, have been modeled and analyzed parametrically. Analysis to date indicates that hybrids can be competitive with mined uranium when U/sub 3/O/sub 8/ cost is about 100 $/lb., adding less than 25% to present day cost of power from LWR's. Of the three blanket types considered, uranium fast fission (UFF), thorium fast fission (ThFF), and thorium fission supressed (ThFS), the ThFS blanket has a modest economic advantage under most conditions but has higher support ratios and potential safety advantages under all conditions.

  9. Performance Optimization of the Gasdynamic Mirror Propulsion System

    NASA Technical Reports Server (NTRS)

    Emrich, William J., Jr.; Kammash, Terry

    1999-01-01

    Nuclear fusion appears to be a most promising concept for producing extremely high specific impulse rocket engines. Engines such as these would effectively open up the solar system to human exploration and would virtually eliminate launch window restrictions. A preliminary vehicle sizing and mission study was performed based on the conceptual design of a Gasdynamic Mirror (GDM) fusion propulsion system. This study indicated that the potential specific impulse for this engine is approximately 142,000 sec. with about 22,100 N of thrust using a deuterium-tritium fuel cycle. The engine weight inclusive of the power conversion system was optimized around an allowable engine mass of 1500 Mg assuming advanced superconducting magnets and a Field Reversed Configuration (FRC) end plug at the mirrors. The vehicle habitat, lander, and structural weights are based on a NASA Mars mission study which assumes the use of nuclear thermal propulsion' Several manned missions to various planets were analyzed to determine fuel requirements and launch windows. For all fusion propulsion cases studied, the fuel weight remained a minor component of the total system weight regardless of when the missions commenced. In other words, the use of fusion propulsion virtually eliminates all mission window constraints and effectively allows unlimited manned exploration of the entire solar system. It also mitigates the need to have a large space infrastructure which would be required to support the transfer of massive amounts of fuel and supplies to lower a performing spacecraft.

  10. The mirror neuron system in post-stroke rehabilitation

    PubMed Central

    2013-01-01

    Different treatments for stroke patients have been proposed; among them the mirror therapy and motion imagery lead to functional recovery by providing a cortical reorganization. Up today the basic concepts of the current literature on mirror neurons and the major findings regarding the use of mirror therapy and motor imagery as potential tools to promote reorganization and functional recovery in post-stroke patients. Bibliographic research was conducted based on publications over the past thirteen years written in English in the databases Scielo, Pubmed/MEDLINE, ISI Web of Knowledge. The studies showed how the interaction among vision, proprioception and motor commands promotes the recruitment of mirror neurons, thus providing cortical reorganization and functional recovery of post-stroke patients. We conclude that the experimental advances on Mirror Neurons will bring new rational therapeutic approaches to post-stroke rehabilitation. PMID:24134862

  11. The mirror neuron system in post-stroke rehabilitation.

    PubMed

    Carvalho, Diana; Teixeira, Silmar; Lucas, Marina; Yuan, Ti-Fei; Chaves, Fernanda; Peressutti, Caroline; Machado, Sergio; Bittencourt, Juliana; Menéndez-González, Manuel; Nardi, Antonio Egidio; Velasques, Bruna; Cagy, Mauricio; Piedade, Roberto; Ribeiro, Pedro; Arias-Carrión, Oscar

    2013-01-01

    Different treatments for stroke patients have been proposed; among them the mirror therapy and motion imagery lead to functional recovery by providing a cortical reorganization. Up today the basic concepts of the current literature on mirror neurons and the major findings regarding the use of mirror therapy and motor imagery as potential tools to promote reorganization and functional recovery in post-stroke patients. Bibliographic research was conducted based on publications over the past thirteen years written in English in the databases Scielo, Pubmed/MEDLINE, ISI Web of Knowledge. The studies showed how the interaction among vision, proprioception and motor commands promotes the recruitment of mirror neurons, thus providing cortical reorganization and functional recovery of post-stroke patients. We conclude that the experimental advances on Mirror Neurons will bring new rational therapeutic approaches to post-stroke rehabilitation.

  12. The Mirror Neuron System and Action Recognition

    ERIC Educational Resources Information Center

    Buccino, Giovanni; Binkofski, Ferdinand; Riggio, Lucia

    2004-01-01

    Mirror neurons, first described in the rostral part of monkey ventral premotor cortex (area F5), discharge both when the animal performs a goal-directed hand action and when it observes another individual performing the same or a similar action. More recently, in the same area mirror neurons responding to the observation of mouth actions have been…

  13. Advanced Mirror Technology Development (AMTD) for Very Large Space Telescopes

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2013-01-01

    Accomplishments include: Assembled outstanding team from academia, industry and government with expertise in science and space telescope engineering. Derived engineering specifications for monolithic primary mirror from science measurement needs & implementation constraints. Pursuing long-term strategy to mature technologies necessary to enable future large aperture space telescopes. Successfully demonstrated capability to make 0.5 m deep mirror substrate and polish it to UVOIR traceable figure specification.

  14. Design and analysis of support system of LAMOST primary mirror

    NASA Astrophysics Data System (ADS)

    Gong, Xuefei; Cui, Xiangqun; Chen, Haiyuan; Ye, Xizhang; Zhang, Ru

    2003-02-01

    LAMOST (The Large Sky Area Multi-object Fiber Spectroscopic Telescope) is a reflecting Schmidt telescope. There are two large segmented mirrors in LAMOST: One is the Schmidt plate MA, and the other is the spherical primary mirror MB. The dimension of MB is about 6.7m×6m and it is face down in 25°. MB is composed of 37 hexagonal sub-mirrors. During the observation, one should maintain the correct mirror figure for each sub-mirror and co-focus for all 37 sub-mirrors to obtain the good image, even it is an unconventional designed telescope without tracking movement on the primary mirror. This paper presents the design and the finite element analysis for the whole primary mirror support system, which includes the optimization of the mirror support points distribution, the design and the testing of the prototype of MB sub-cell, the structure analysis and the design of the mirror support truss.

  15. The Gasdynamic Mirror Fusion Propulsion System -- Revisited

    SciTech Connect

    Kammash, Terry; Tang, Ricky

    2005-02-06

    Many of the previous studies assessing the capability of the gasdynamic mirror (GDM) fusion propulsion system employed analyses that ignored the 'ambipolar' potential. This electrostatic potential arises as a result of the rapid escape of the electrons due to their small mass. As they escape, they leave behind an excess positive charge which manifests itself in an electric field that slows down the electrons while speeding up the ions until their respective axial diffusions are equalized. The indirect effect on the ions is that their confinement time is reduced relative to that of zero potential, and hence the plasma length must be increased to accommodate that change. But as they emerge from the thruster mirror - which serves as a magnetic nozzle - the ions acquire an added energy equal to that of the potential energy, and that in turn manifests itself in increased specific impulse and thrust. We assess the propulsive performance of the GDM thruster, based on the more rigorous theory, by applying it to a round trip Mars mission employing a continuous burn acceleration/deceleration type of trajectory. We find that the length of the device and travel time decrease with increasing plasma density, while the total vehicle mass reaches a minimum at a plasma density of 3 x 1016 cm-3. At such a density, and an initial DT ion temperature of 10 keV, a travel time of 60 days is found to be achievable at GDM propulsion parameters of about 200,000 seconds of specific impulse and approximately 47 kN of thrust.

  16. Magnetic mirror fusion systems: Characteristics and distinctive features

    SciTech Connect

    Post, R.F.

    1987-08-10

    A tutorial account is given of the main characteristics and distinctive features of conceptual magnetic fusion systems employing the magnetic mirror principle. These features are related to the potential advantages that mirror-based fusion systems may exhibit for the generation of economic fusion power.

  17. Production of metal matrix composite mirrors for tank fire control systems

    NASA Astrophysics Data System (ADS)

    Geiger, Alan L.; Ulph, Eric, Sr.

    1992-09-01

    The first production lot of 50 units of metal matrix composite mirrors for the Leopard I tank fire control system was recently completed by Optical Corporation of America (OCA), Garden Grove, California. The mirror substrates were finish machined from forgings of Optical Grade SXATM metal matrix composite manufactured by Advanced Composite Materials Corporation (ACMC), Greer, South Carolina. Use of forgings rather than hot pressed billet yields more efficient use of material and reduces machining time, resulting in lower cost. The mirrors were fabricated by a process sequence of machining, thermal stabilization, electroless nickel plating, polishing, and coating with a high efficiency, laser damage-resistant optical coating. The mirrors are used in the fire control system for a day channel (direct view) and near infrared (CCD), a muzzle reference system laser transceiver, a laser range finder, and an infrared thermal imaging system. SXA composite was chosen over competitive mirror materials (glass and beryllium) because of its high specific strength and stiffness, good stability, and moderate machining cost. The mirrors exhibit excellent stability and optical performance. Field trials of prototype mirrors in fire control systems have proven successful.

  18. Status of the Advanced Mirror Technology Development (AMTD) Phase 2, 1.5m ULE(Registered Trademark) Mirror

    NASA Technical Reports Server (NTRS)

    Egerman, Robert; Matthews, Gary W.; Johnson, Matthew; Ferland, Albert; Stahl, H. Philip; Eng, Ron; Effinger, Michael R.

    2015-01-01

    The Decadal Survey stated that an advanced large-aperture ultraviolet, optical, near-infrared (UVOIR) telescope is required to enable the next generation of compelling astrophysics and exoplanet science; and, that present technology is not mature enough to affordably build and launch any potential UVOIR mission concept. Under Science and Technology funding, NASA's Marshall Space Flight Center (MSFC) and Exelis have developed a more cost effective process to make up to 4m monolithic spaceflight UV quality, low areal density, thermally and dynamically stable primary mirrors. Under a Phase I program, a proof of concept mirror was completed at Exelis and tested down to 250K at MSFC which would allow imaging out to 2.5 microns. In 2014, Exelis and NASA started a Phase II program to design and build a 1.5m mirror to demonstrate lateral scalability to a 4m monolithic primary mirror. The current status of the Phase II development program will be provided along with a Phase II program summary.

  19. Modeling electrostrictive deformable mirrors in adaptive optics systems

    NASA Astrophysics Data System (ADS)

    Hom, Craig L.; Dean, Peter D.; Winzer, Stephen R.

    2000-06-01

    Adaptive optics correct light wavefront distortion caused by atmospheric turbulence or internal heating of optical components. This distortion often limits performance in ground-based astronomy, space-based earth observation and high energy laser applications. The heart of the adaptive optics system is the deformable mirror. In this study, an electromechanical model of a deformable mirror was developed as a design tool. The model consisted of a continuous, mirrored face sheet driven with multilayered, electrostrictive actuators. A fully coupled constitutive law simulated the nonlinear, electromechanical behavior of the actuators, while finite element computations determined the mirror's mechanical stiffness observed by the array. Static analysis of the mirror/actuator system related different electrical inputs to the array with the deformation of the mirrored surface. The model also examined the nonlinear influence of internal stresses on the active array's electromechanical performance and quantified crosstalk between neighboring elements. The numerical predictions of the static version of the model agreed well with experimental measurements made on an actual mirror system. The model was also used to simulate the systems level performance of a deformable mirror correcting a thermally bloomed laser beam. The nonlinear analysis determined the commanded actuator voltages required for the phase compensation and the resulting wavefront error.

  20. Optimal two-mirror system for laser radiation focusing

    SciTech Connect

    Gitin, Andrey V

    2009-10-31

    An optical system for laser radiation focusing, which consists of parabolic and elliptic mirrors, is considered. It is shown by the method of elementary reflections that the maximum concentration of laser radiation on the target can be achieved at a certain position of these mirrors. (laser applications and other topics in quantum electronics)

  1. LSST primary, secondary, and tertiary mirror support systems

    NASA Astrophysics Data System (ADS)

    Cuerden, Brian; Sebag, Jacques; Mathews, Scott; Cho, Myung; Lee, Joon; West, Steven

    2004-09-01

    The current LSST Baseline Configuration has a field of view of 3.5 degrees and an optical etendue of 302 meters square degrees square. The etendue calculation includes the effect of gradual vignetting by the camera as the field angle increases. A current optical point design includes an 8.4 m spun cast light-weighted borosilicate primary mirror, a 3.2 m secondary mirror and a 5.0 m tertiary mirror. The goal of this study is to determine if these mirrors can be actively supported and retain figure control over elevation angles without closed-loop control based on wave-front measurement. Support systems for the tertiary and primary mirrors are adapted from proven systems utilized on 6.5 and 8.4 m class primaries developed by the University of Arizona"s Mirror Laboratory. The number and locations of axial and lateral supports is determined for each mirror and the gravitational and support induced surface distortions are calculated and are shown to be within budgeted limits. The support components and their performance are described and it is demonstrated that predicted mirror distortion attributable to the support system is consistent with the known performance of the support components.

  2. Adaptive optics ophthalmologic systems using dual deformable mirrors

    SciTech Connect

    Jones, S; Olivier, S; Chen, D; Sadda, S; Joeres, S; Zawadzki, R; Werner, J S; Miller, D

    2007-02-01

    Adaptive Optics (AO) have been increasingly combined with a variety of ophthalmic instruments over the last decade to provide cellular-level, in-vivo images of the eye. The use of MEMS deformable mirrors in these instruments has recently been demonstrated to reduce system size and cost while improving performance. However, currently available MEMS mirrors lack the required range of motion for correcting large ocular aberrations, such as defocus and astigmatism. In order to address this problem, we have developed an AO system architecture that uses two deformable mirrors, in a woofer/tweeter arrangement, with a bimorph mirror as the woofer and a MEMS mirror as the tweeter. This setup provides several advantages, including extended aberration correction range, due to the large stroke of the bimorph mirror, high order aberration correction using the MEMS mirror, and additionally, the ability to ''focus'' through the retina. This AO system architecture is currently being used in four instruments, including an Optical Coherence Tomography (OCT) system and a retinal flood-illuminated imaging system at the UC Davis Medical Center, a Scanning Laser Ophthalmoscope (SLO) at the Doheny Eye Institute, and an OCT system at Indiana University. The design, operation and evaluation of this type of AO system architecture will be presented.

  3. [Mirror neuron system dysfunction in schizophrenia and its clinical implication].

    PubMed

    Kato, Motoichiro; Kato, Yutaka

    2014-06-01

    Since the discovery of mirror neuron system, several neurophysiological and neuroimaging studies showed that the mirror neuron system might have a role in understanding other people's actions and intentions with automatic simulation of their actions. Moreover, some studies suggested that mirror neurons have a broader role in social cognition including understanding others' emotions and empathy. It has not been proved, however, whether the mirror neuron system is necessarily involved in empathy processes. In the domain of social cognition deficits, it is important to investigate the involvement of mirror neuron system dysfunction in psychosis such as schizophrenia. Using magnetoencephalography, we examined whether antipsychotic-free schizophrenia patients displayed mirror neuron system dysfunction during observation of biological motion (jaw movement). Compared with normal controls, the patients with schizophrenia had fewer components of both the waveform and equivalent current dipole, suggesting aberrant brain activity resulting from dysfunction of the right inferior parietal cortex. They also lacked the changes of alpha band and gamma band oscillation seen in normal controls, and had weaker phase locking factors and gamma-synchronization predominantly in right parietal cortex. This finding demonstrated that untreated patients with schizophrenia exhibited aberrant mirror neuron system function based on the right inferior parietal cortex, which is characterized by dysfunction of gamma-synchronization.

  4. Mirror theory applied to toroidal systems

    SciTech Connect

    Cohen, R.H.

    1987-08-25

    Central features of a mirror plasma are strong departures from Maxwellian distribution functions, ambipolar potentials and densities which vary along a field line, and losses, and the mirror field itself. To examine these features, mirror theorists have developed analytical and numerical techniques to solve the Fokker-Planck equation, evaluate the potentials consistent with the resulting distribution functions, and assess the microstability of these distributions. Various combinations of mirror-plasma fetures are present and important in toroidal plasmas as well, particularly in the edge region and in plasmas with strong r.f. heating. In this paper we survey problems in toroidal plasmas where mirror theory and computational techniques are applicable, and discuss in more detail three specific examples: calculation of the toroidal generalization of the Spitzer-Haerm distribution function (from which trapped-particle effects on current drive can be calculated), evaluation of the nonuniform potential and density set up by pulsed electron-cyclotron heating, and calculation of steady-state distribution functions in the presence of strong r.f. heating and collisions. 37 refs., 3 figs.

  5. Microinstabilities in the Gasdynamic Mirror Propulsion System

    NASA Technical Reports Server (NTRS)

    Emrich, William

    2005-01-01

    The gasdynamic mirror has been proposed as a concept which could form the basis of a highly efficient fusion rocket engine. Gasdynamic mirrors differ from most other mirror type plasma confinement schemes in that they have much larger aspect ratios and operate at somewhat higher plasma densities. There are several types of instabilities which are known to plague mirror type confinement schemes. These instabilities fall into two general classes. One class of instability is the Magnetohdrodynamic or MHD instability which induces gross distortions in the plasma geometry. The other class of instability is the "loss cone" microinstability which leads to general plasma turbulence. The "loss cone" microinstability is caused by velocity space asymmetries resulting from the loss of plasma having constituent particle velocities within the angle of the magnetic mirror "loss cone." These instabilities generally manifest themselves in high temperature, moderately dense plasmas. The present study indicates that a GDM configured as a rocket engine might operate in a plasma regine where microinstabilities could potentially be significant.

  6. Microinstabilities in the Gasdynamic Mirror Propulsion System

    NASA Technical Reports Server (NTRS)

    Emrich, William

    2005-01-01

    The gasdynamic mirror has been proposed as a concept which could form the basis of a highly efficient fusion rocket engine. Gasdynamic mirrors differ from most other mirror type plasma confinement schemes in that they have much larger aspect ratios and operate at somewhat higher plasma densities. There are several types of instabilities which are known to plague mirror type confinement schemes. These instabilities fall into two general classes. One class of instability is the Magnetohydrodynamic or MHD instability which induces gross distortions in the plasma geometry. The other class of instability is the "loss cone" microinstability which leads to general plasma turbulence. The "loss cone" microinstability is caused by velocity space asymmetries resulting from the loss of plasma having constituent particle velocities within the angle of the magnetic mirror "loss cone." These instabilities generally manifest themselves in high temperature, moderately dense plasmas. The present study indicates that a GDM configured as a rocket engine might operate in a plasma regime where microinstabilities could potentially be significant.

  7. A low-cost mirror mount control system for optics setups

    NASA Astrophysics Data System (ADS)

    Gopalakrishnan, Maithreyi; Gühr, Markus

    2015-02-01

    We describe a flexible, simple to build, low-cost, and computer-controlled optical mirror actuator system, developed for undergraduate research laboratories. Geared motors for hobby robotics are controlled by an Arduino microcontroller in combination with an H bridge to finely position mirror mount actuators. We present a graphical user interface based on the Python script language. The price of the fully controlled actuator system is only a small fraction of the price of a commercial system. It can be quickly implemented due to the use of open-hardware electronics. We discuss the performance of the system and give an outlook for future expansions and use in advanced optical setups.

  8. Large aperture micro-focus KB mirrors for spectroscopy experiments at the Advanced Light Source

    SciTech Connect

    Warwick, T.; Andresen, N.; Comins, J.; Franck, A.; Gilles, M.; Tonnessen, T.; Tyliszczak, T.

    2004-06-04

    General purpose refocus mirrors using Kirkpatrick-Baez geometry have been designed, built and installed at a new undulator beam-line facility to provide spot sizes smaller than 10 microns for specialized spectroscopy experiments at the Advanced Light Source. All the available flux is focused and the focal length is adjustable. The mirrors are fully computer controlled and can be detuned to create a spot as big as 500 microns.

  9. Performance prediction of the TMT tertiary mirror support system

    NASA Astrophysics Data System (ADS)

    Cho, Myung K.

    2008-07-01

    The Ritchey-Chretien (RC) optical design of Thirty Meter Telescope (TMT) calls for a 3.1m diameter secondary mirror (M2M) and an elliptical tertiary mirror (M3M) of 3.5m along its major axis and 2.5m along its minor axis. The M3M is a thin, large, flat, solid elliptical mirror which directs the f/15 beam from the M2M to the multiple instruments on both Nasmyth platforms. The M3M will weigh approximately two metric tons and the mirror support system will maintain the mirror figure at different gravity orientations. A recent reduction of the field of view to 15 arc minutes allows a reduction in the size of the M3M, which in turn requires re-optimization of the mirror support system. The proposed M3M optimized support system consists of 60 tri-axial supports mounted at the mirror back surface. These tri-axial supports accommodate motions of M3M in three gravity directions. The print-though RMS surface errors of M3M are 10nm for axial gravity loadings and 1nm for lateral gravity loadings. The M3 system (M3S) has an active optics (aO) capability to accommodate potential mechanical or thermal errors; its ability to correct low-order aberrations has been analyzed. A structure function (SF) of the axial gravity support print-through was calculated.

  10. Advanced High Reflector Coatings for the Giant Segmented Mirror Telescope

    SciTech Connect

    Martin, Peter M.; Bennett, Wendy D.; Phillips, A.; Brown, W.; Wallace, V.; Stillburn, James; Sabag, Jacques

    2006-09-01

    The Association of Universities for Research Astronomy’s (AURA) New Initiatives Office (NIO) is developing a Giant Segmented Mirror Telescope (GSMT), a next generation telescope also known as the Thirty Meter Telescope (TMT). The telescope, whose present design consist of six hundred eighteen 1.2 m diameter mirrors, will have truly remarkable performance. It will be able to resolve crowded star fields into individual stars in galaxies as far away as 10 million light years. It will be able to image and analyze planets and dust clouds around hundreds of nearby stars. Imaging will range from the ultraviolet (UV) to long wavelength infrared (LWIR) wavelengths. The goal is to have the telescope operational by 2014. Figure 1 shows a conceptual picture of the GSMT compared to the 10-m Keck telescope and Figure 2 shows a conceptual picture of the observatory.

  11. Imaging performance of elliptical-boundary varifocal mirrors in active optical systems

    NASA Astrophysics Data System (ADS)

    Lukes, Sarah Jane

    Micro-electro-mechanical systems deformable-membrane mirrors provide a means of focus control and attendant spherical aberration correction for miniaturized imaging systems. The technology has greatly advanced in the last decade, thereby extending their focal range capabilities. This dissertation describes a novel SU-8 2002 silicon-on-insulator wafer deformable mirror. A 4.000 mm x 5.657 mm mirror for 45o incident light rays achieves 22 mum stroke or 65 diopters, limited by snapdown. The mirrors show excellent optical quality while flat. Most have peak-to-valley difference of less than 150 nm and root-mean-square less than 25 nm. The process proves simple, only requiring a silicon-on-insulator wafer, SU-8 2002, and a metal layer. Xenon difluoride etches the silicon to release the mirrors. Greater than 90% of the devices survive fabrication and release. While current literature includes several aberration analyses on static mirrors, analyses that incorporate the dynamic nature of these mirrors do not exist. Optical designers may have a choice between deformable mirrors and other types of varifocal mirrors or lenses. Furthermore, a dynamic mirror at an incidence angle other than normal may be desired due to space limitations or for higher throughput (normal incidence requires a beam splitter). This dissertation presents an analysis based on the characteristic function of the system. It provides 2nd and 3rd order aberration coefficients in terms of dynamic focus range and base ray incidence angle. These afford an understanding of the significance of different types of aberrations. Root-mean-square and Strehl calculations provide insight into overall imaging performance for various conditions. I present general guidelines for maximum incidence angle and field of fiew that provide near diffraction-limited performance. Experimental verification of the MEMS mirrors at 5o and 45o incidence angles validates the analytical results. A Blu-ray optical pick-up imaging

  12. Deformable mirror design of Subaru LGSAO system

    NASA Astrophysics Data System (ADS)

    Oya, Shin; Guyon, Olivier; Watanabe, Makoto; Hayano, Yutaka; Takami, Hideki; Iye, Masanori; Arimoto, Nobuo; Colley, Stephen; Eldred, Michael; Kane, Thomas; Hattori, Masayuki; Saito, Yoshihiko; Kamata, Yukiko; Kobayashi, Naoto; Minowa, Yosuke; Goto, Miwa; Takato, Naruhisa

    2004-10-01

    As an upgrade plan of Subaru adaptive optics facility, laser-guide-star adaptive-optics (LGSAO) project is on going. One of key components of the project is a deformable mirror (DM). The DM for LGSAO is a bimorph type of PZT with 188 control elements. The specification of design is presented together with the analysis of stroke and vibration properties by FEM.

  13. An image stabilization optical system using deformable freeform mirrors.

    PubMed

    Hao, Qun; Cheng, Xuemin; Kang, Jiqiang; Jiang, Yuhua

    2015-01-01

    An image stabilization optical system using deformable freeform mirrors is proposed that enables the ray sets to couple dynamically in the object and image space. It aims to correct image blurring and degradation when there is relative movement between the imaging optical axis and the object. In this method, Fermat's principle and matrix methods are used to describe the optical path of the entire optical system with a shift object plane and a fixed corresponding image plane in the carrier coordinate system. A constant optical path length is determined for each ray set, so the correspondence between the object and the shift free image point is used to calculate the solution to the points on the surface profile of the deformable mirrors (DMs). Off-axis three-mirror anastigmats are used to demonstrate the benefits of optical image stabilization with one- and two-deformable mirrors. PMID:25599423

  14. An image stabilization optical system using deformable freeform mirrors.

    PubMed

    Hao, Qun; Cheng, Xuemin; Kang, Jiqiang; Jiang, Yuhua

    2015-01-15

    An image stabilization optical system using deformable freeform mirrors is proposed that enables the ray sets to couple dynamically in the object and image space. It aims to correct image blurring and degradation when there is relative movement between the imaging optical axis and the object. In this method, Fermat's principle and matrix methods are used to describe the optical path of the entire optical system with a shift object plane and a fixed corresponding image plane in the carrier coordinate system. A constant optical path length is determined for each ray set, so the correspondence between the object and the shift free image point is used to calculate the solution to the points on the surface profile of the deformable mirrors (DMs). Off-axis three-mirror anastigmats are used to demonstrate the benefits of optical image stabilization with one- and two-deformable mirrors.

  15. An Image Stabilization Optical System Using Deformable Freeform Mirrors

    PubMed Central

    Hao, Qun; Cheng, Xuemin; Kang, Jiqiang; Jiang, Yuhua

    2015-01-01

    An image stabilization optical system using deformable freeform mirrors is proposed that enables the ray sets to couple dynamically in the object and image space. It aims to correct image blurring and degradation when there is relative movement between the imaging optical axis and the object. In this method, Fermat's principle and matrix methods are used to describe the optical path of the entire optical system with a shift object plane and a fixed corresponding image plane in the carrier coordinate system. A constant optical path length is determined for each ray set, so the correspondence between the object and the shift free image point is used to calculate the solution to the points on the surface profile of the deformable mirrors (DMs). Off-axis three-mirror anastigmats are used to demonstrate the benefits of optical image stabilization with one- and two-deformable mirrors. PMID:25599423

  16. Lightweight diaphragm mirror module system for solar collectors

    DOEpatents

    Butler, Barry L.

    1985-01-01

    A mirror module system is provided for accurately focusing solar radiation on a point or a line as defined by an array of solar collectors. Each mirror module includes a flexible membrane stretched over a frame in a manner similar to that of a drum or a trampoline and further includes a silvered glass or plastic mirror for forming an optical reflecting surface. The configuration of the optical reflecting surface is variably adjustable to provide for the accurate focusing of the solar energy on a given collector array, e.g., a point or a linear array arrangement. The flexible mirror-membrane combination is lightweight to facilitate installation and reduce system cost yet structurally strong enough to provide for the precise focusing of the incident solar radiation in a semi-rigid reflector system in which unwanted reflector displacement is minimized.

  17. Lightweight diaphragm mirror module system for solar collectors

    DOEpatents

    Butler, B.L.

    1984-01-01

    A mirror module system is provided for accurately focusing solar radiation on a point or a line as defined by an array of solar collectors. Each mirror module includes a flexible membrane stretched over a frame in a manner similar to that of a drum or a trampoline and further includes a silvered glass or plastic mirror for forming an optical reflecting surface. The configuration of the optical reflecting surface is variably adjustable to provide for the accurate focusing of the solar energy on a given collector array, e.g., a point or a linear array arrangement. The flexible mirror-membrane combination is lightweight to facilitate installation and reduce system cost yet structurally strong enough to provide for the precise focusing of the incident solar radiation in a semi-rigid reflector system in which unwanted reflector displacement is minimized.

  18. Performance prediction of the TMT secondary mirror support system

    NASA Astrophysics Data System (ADS)

    Cho, Myung K.

    2008-07-01

    The Ritchey-Chretien (RC) design of the Thirty Meter Telescope (TMT) optics calls for a 3.1 m diameter Secondary Mirror (M2), which is a large meniscus convex hyperboloid. The M2 converts the beam reflected from the f/1 primary mirror into an f/15 beam for the science instruments. The M2 Mirror (M2M) has a mass of approximately two metric tons and the mirror support system will need to maintain the mirror figure at different gravity orientations. Recent changes in the telescope configuration to RC from Aplanatic Gregorian (AG) prescription and reduction of the fully-illuminated field of view to 15 arc minutes required a design change in the M2 mirror figure from a concave radius to a convex radius, with a significant reduction in diameter, which in turn requires re-optimization of the mirror support systems. The optical performance evaluations were made based on the optimized support systems resulting from the change from AG to RC. The M2 optimized support system consists of 60 axial supports, mounted at the mirror back surface, and 24 lateral supports mounted along the outer edge. The predicted print-though errors of the M2M supports are 10nm RMS surface for axial gravity and 2nm RMS surface for lateral gravity. This M2M support system has an active optics capability to accommodate potential mechanical or thermal errors; its performance to correct low-order aberrations has been analyzed. A structure function of the axial gravity support print-through was calculated.

  19. Bipod flexure for 1-m primary mirror system.

    PubMed

    Kihm, Hagyong; Yang, Ho-Soon; Lee, Yun-Woo

    2014-12-01

    We present an analytical formulation of the bipod flexure for mounting the 1-m primary mirror in a space telescope. Compliance and stiffness matrices of the bipod flexure are derived to estimate theoretical performance and to make initial design guidelines. We use finite element analysis to optimize the bipod design satisfying the application requirements. Experimental verification is achieved by vibration test with a dummy mirror system. PMID:25554320

  20. James Webb Space Telescope (JWST) Primary Mirror Material Selection

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip; Feinberg, Lee D.; Russell, Kevin; Texter, Scott

    2004-01-01

    The James Webb Space Telescope (JWST) conducted a phase down select process via the Advanced Mirror System Demonstrator (AMSD) project to assess the Technology Readiness Level of various candidate mirror materials. This process culminated in the selection of Beryllium as the JWST primary mirror material. This paper outlines the mirror evaluation process, defines the selection criteria and summarizes the candidate mirror's performances.

  1. Overview and Accomplishments of Advanced Mirror Technology Development Phase 2 (AMTD-2) Project

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2015-01-01

    The Advance Mirror Technology Development (AMTD) project is in Phase 2 of a multiyear effort, initiated in FY12, to mature by at least a half TRL step critical technologies required to enable 4 meter or larger UVOIR space telescope primary mirror assemblies for both general astrophysics and ultra-high contrast observations of exoplanets. AMTD Phase 1 completed all of its goals and accomplished all of its milestones. AMTD Phase 2 started in 2014. Key accomplishments include deriving primary mirror engineering specifications from science requirements; developing integrated modeling tools and using those tools to perform parametric design trades; and demonstrating new mirror technologies via sub-scale fabrication and test. AMTD-1 demonstrated the stacked core technique by making a 43-cm diameter 400 mm thick 'biscuit-cut' of a 4-m class mirror. AMTD-2 is demonstrating lateral scalability of the stacked core method by making a 1.5 meter 1/3rd scale model of a 4-m class mirror.

  2. EST Telescope: primary mirror, support, and cooling system

    NASA Astrophysics Data System (ADS)

    Volkmer, R.; Manni, F.; Giannuzzi, M.; Scotto, A.; Cavaller, L.; Scheiffelen, T.; Bettonvil, F.; Berrilli, F.

    2010-07-01

    The solar telescope EST is currently in the conceptual design phase. It is planned to be build on the Canary Islands until end of the decade. It is specialized on polarimetric observations and will provide high spatial and spectral observations of the different solar atmospheric layers. The diameter of the primary mirror blank is 4.2m. Different types of mirror shapes were investigated with respect to thermal and mechanical characteristics. To remove the absorbed heat an air cooling system from the back side will be applied. Additional an air flushing system will remove remaining warm air from the front side. A major problem of a large open telescope will be the wind load. Results of the investigations will be shown. To achieve optimal optical performance an active support system is planned. The primary mirror cell needs to be stiff enough to support the primary mirror without deformation at strong wind in case of the open telescope option, but sufficient room for the active support system and cooling system below the backside of the mirror is also required. Preliminary designs and analysis results will be presented.

  3. A novel collinear optical system with annulus mirrors for holographic disc driver

    NASA Astrophysics Data System (ADS)

    Wang, Ye

    2008-12-01

    This paper focus on a novel collinear lens system with annulus mirrors for holographic disc driver, both information beam and reference beam are use same laser beam. The expanded and parallel laser beam, center part of it as the information beam then through Fourier transform lens, the beam around center part as a reference beam. On this axis, the ring reference beam reflected by two annulus shaped mirrors, then became a convergent beam, together with the information beam which through the first Fourier transform lens then produce holographic pattern to be write into the holographic disc behind of them, this lens system with two mirrors made the angle between information beam and reference beam more wide, can improved the multiplex level of holographic storage. Pair of Fourier transform lens with advance performance is designed in this paper.

  4. Primary mirror support system for the SUBARU Telescope

    NASA Astrophysics Data System (ADS)

    Iye, Masanori; Kodaira, Keiichi

    1994-06-01

    The Japan National Large Telescope `SUBARU' will be completed on the summit of Mauna Kea by the end of the century. One of the major characteristics new to the SUBARU telescope is the active support system for its large monolithic primary mirror, which has 261 points of computer-controlled actuators to maintain a precise mirror figure. This paper describes the control principle, design concepts, results of engineering experiments and numerical simulations of the active support system to ensure the high imaging performance of this system.

  5. Advanced materials for multilayer mirrors for extreme ultraviolet solar astronomy.

    PubMed

    Bogachev, S A; Chkhalo, N I; Kuzin, S V; Pariev, D E; Polkovnikov, V N; Salashchenko, N N; Shestov, S V; Zuev, S Y

    2016-03-20

    We provide an analysis of contemporary multilayer optics for extreme ultraviolet (EUV) solar astronomy in the wavelength ranges: λ=12.9-13.3  nm, λ=17-21  nm, λ=28-33  nm, and λ=58.4  nm. We found new material pairs, which will make new spaceborne experiments possible due to the high reflection efficiencies, spectral resolution, and long-term stabilities of the proposed multilayer coatings. In the spectral range λ=13  nm, Mo/Be multilayer mirrors were shown to demonstrate a better ratio of reflection efficiency and spectral resolution compared with the commonly used Mo/Si. In the spectral range λ=17-21  nm, a new multilayer structure Al/Si was proposed, which had higher spectral resolution along with comparable reflection efficiency compared with the commonly used Al/Zr multilayer structures. In the spectral range λ=30  nm, the Si/B4C/Mg/Cr multilayer structure turned out to best obey reflection efficiency and long-term stability. The B4C and Cr layers prevented mutual diffusion of the Si and Mg layers. For the spectral range λ=58  nm, a new multilayer Mo/Mg-based structure was developed; its reflection efficiency and long-term stability have been analyzed. We also investigated intrinsic stresses inherent for most of the multilayer structures and proposed possibilities for stress elimination.

  6. Advanced materials for multilayer mirrors for extreme ultraviolet solar astronomy.

    PubMed

    Bogachev, S A; Chkhalo, N I; Kuzin, S V; Pariev, D E; Polkovnikov, V N; Salashchenko, N N; Shestov, S V; Zuev, S Y

    2016-03-20

    We provide an analysis of contemporary multilayer optics for extreme ultraviolet (EUV) solar astronomy in the wavelength ranges: λ=12.9-13.3  nm, λ=17-21  nm, λ=28-33  nm, and λ=58.4  nm. We found new material pairs, which will make new spaceborne experiments possible due to the high reflection efficiencies, spectral resolution, and long-term stabilities of the proposed multilayer coatings. In the spectral range λ=13  nm, Mo/Be multilayer mirrors were shown to demonstrate a better ratio of reflection efficiency and spectral resolution compared with the commonly used Mo/Si. In the spectral range λ=17-21  nm, a new multilayer structure Al/Si was proposed, which had higher spectral resolution along with comparable reflection efficiency compared with the commonly used Al/Zr multilayer structures. In the spectral range λ=30  nm, the Si/B4C/Mg/Cr multilayer structure turned out to best obey reflection efficiency and long-term stability. The B4C and Cr layers prevented mutual diffusion of the Si and Mg layers. For the spectral range λ=58  nm, a new multilayer Mo/Mg-based structure was developed; its reflection efficiency and long-term stability have been analyzed. We also investigated intrinsic stresses inherent for most of the multilayer structures and proposed possibilities for stress elimination. PMID:27140543

  7. Active support system for 1-m SONG primary mirror

    NASA Astrophysics Data System (ADS)

    Niu, Dongsheng; Wang, Guomin; Gu, Bozhong

    2012-05-01

    Chinese-node telescope of Stellar Observations Network Group (SONG) has a primary mirror 1m in diameter with flat back, which will be supported actively. The performance evaluation of the telescope's active optics system is conducted. Finite element analysis (FEA) is employed to analyze the optical surface figures of the primary mirror, and two optimizations are carried out by using ANSYS: (1) the locations and forces of axial supports are optimized with the telescope pointing to zenith; (2) the lateral support forces are calculated with the telescope pointing to horizon. Axial support force sensitivities are calculated in a case that a single axial support has a force error of 0.5N. The correction ability of the active support system is analyzed when an arbitrary axial support is failure. Several low order Zernike modes are modeled with MATLAB procedure, and active optics corrections are applied to these modes. Thermal deformation of the mirror is also corrected using active support system.

  8. Advanced UVOIR Mirror Technology Development (AMTD) for Very Large Space Telescopes

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip; Smith, W. Scott; Mosier, Gary; Abplanalp, Laura; Arnold, William

    2014-01-01

    ASTRO2010 Decadal stated that an advanced large-aperture ultraviolet, optical, near-infrared (UVOIR) telescope is required to enable the next generation of compelling astrophysics and exoplanet science; and, that present technology is not mature enough to affordably build and launch any potential UVOIR mission concept. AMTD builds on the state of art (SOA) defined by over 30 years of monolithic & segmented ground & space-telescope mirror technology to mature six key technologies. AMTD is deliberately pursuing multiple design paths to provide the science community with op-tions to enable either large aperture monolithic or segmented mirrors with clear engineering metrics traceable to science requirements.

  9. Crack Branching and Fracture Mirror Data of Glasses and Advanced Ceramics

    NASA Technical Reports Server (NTRS)

    Choi, Sung R.; Gyekenyesi, John P.

    1998-01-01

    The fracture mirror and crack branching constants were determined from three glasses and nine advanced ceramics tested under various loading and specimen configurations in an attempt to use the constants as a data base for fractography. The ratios of fracture mirror or crack branching constant to fracture toughness were found to be approximately two for most ceramic materials tested. A demonstration of how to use the two constants as a tool for verifying stress measurements was presented for silicon nitride disk specimens subjected to high-temperature, constant stress-rate biaxial flexure testing.

  10. Scan mirrors relay for high resolution laser scanning systems

    NASA Astrophysics Data System (ADS)

    Kessler, David

    2014-09-01

    Two dimensional beam deflection is often required in medical laser scanning systems such as OCT or confocal microscopy. Commonly two linear galvo mirrors are used for performance in terms of their large apertures and scan angles. The galvo mirrors are placed at the vicinity of entrance pupil of the scan lens with a "displacement distance" separating them. This distance limits the scan fields and/or reduces the effective aperture of the scan lens. Another option is to use a beam or pupil relay, and image one galvo mirror onto the other. However, beam (or pupil) relays are notoriously complicated, expensive and can add significant aberrations. This paper discusses a simple, all reflective, diffraction limited, color corrected, beam relay, capable of large scan angles and large deflecting mirrors. The design is based on a unique combination of an Offner configuration with a Schmidt aspheric corrector. The design is highly corrected up to large scan mirrors and large scan angles down to milliwaves of aberrations. It allows significantly larger scan field and or scan lenses with higher numerical aperture as compared with scanners using galvos separated by the displacement distance. While this relay is of exceptionally high performance, it has one element located where the beam is focused which may present a problem for high power lasers. Thus modifications of the above design are introduced where the beam is focused in mid air thus making it usable for high power systems such including laser marking and fabrication systems.

  11. MHD-stable plasma confinement in an axisymmetric mirror system

    SciTech Connect

    Stupakov, G.V.

    1988-02-01

    If the magnetic field of a nonparaxial mirror system is chosen appropriately, it is possible to maintain a sharp plasma boundary in an open axisymmetric confinement system in a manner which is stable against flute modes (both global and small-scale). Stability prevails in the ideal MHD approximation without finite-ion-Larmor radius effects.

  12. Robust control of a bimorph mirror for adaptive optics systems.

    PubMed

    Baudouin, Lucie; Prieur, Christophe; Guignard, Fabien; Arzelier, Denis

    2008-07-10

    We apply robust control techniques to an adaptive optics system including a dynamic model of the deformable mirror. The dynamic model of the mirror is a modification of the usual plate equation. We propose also a state-space approach to model the turbulent phase. A continuous time control of our model is suggested, taking into account the frequential behavior of the turbulent phase. An H(infinity) controller is designed in an infinite-dimensional setting. Because of the multivariable nature of the control problem involved in adaptive optics systems, a significant improvement is obtained with respect to traditional single input-single output methods.

  13. Performance of a collimating L-shaped laterally graded multilayer mirror for the IXS analyzer system at NSLS-II.

    PubMed

    Suvorov, Alexey; Coburn, David S; Cunsolo, Alessandro; Keister, Jeffrey W; Upton, Mary H; Cai, Yong Q

    2014-05-01

    The L-shaped laterally graded multilayer mirror is a vital part of the ultrahigh-energy and momentum-resolution inelastic X-ray scattering spectrometer at the National Synchrotron Light Source II. This mirror was designed and implemented as a two-dimensional collimating optic for the analyzer system. Its performance was characterized using a secondary large-divergence source at the 30-ID beamline of the Advanced Photon Source, which yielded an integrated reflectivity of 47% and a collimated beam divergence of 78 µrad with a source size of 10 µm. Numerical simulations of the mirror performance in tandem with the analyzer crystal optics provided details on the acceptance sample volume in forward scattering and defined the technical requirements on the mirror stability and positioning precision. It was shown that the mirror spatial and angular stability must be in the range <8.4 µm and <21.4 µrad, respectively, for reliable operation of the analyzer.

  14. Toward a functional account of the human mirror system. Comment on "Grasping synergies: A motor-control approach to the mirror neuron mechanism" by A. D'Ausilio et al.

    NASA Astrophysics Data System (ADS)

    Enticott, Peter G.

    2015-03-01

    It has been more than 20 years since the first reports of macaque "mirror neurons" appeared in the literature [1], and a large number of studies have since established an analogous system in the human brain [2]. Despite a raft of studies using various methodological approaches, we appear to be moving further away from any form of consensus, particularly concerning what this mirror system actually "mirrors" (e.g., low-level motor representation, goal or intention coding), and the functional significance (if any) of this mechanism [3]. The conceptual issues discussed by D'Ausilio et al. [4] are indeed critical to the advancement of this field; interestingly, they suggest that examining kinematic vs. goal coding aspects of the mirror system might be redundant, and propose instead a new approach that examines the recruitment of motor synergies within the context of the mirror system.

  15. LBT primary mirrors: the final design of the supporting system

    NASA Astrophysics Data System (ADS)

    Parodi, Giancarlo; Cerra, G. C.; Hill, John M.; Davison, Warren B.; Salinari, Piero

    1997-03-01

    The main final results in terms of stresses and optical performances are reported for the large binocular telescope (LBT) primary mirrors. The two borosilicate LBT primary mirrors f/1.14 have 8.4 diameter and are produced at the Steward Observatory Mirror Lab (SOML). They are honeycomb shaped in order to achieve light weight, short thermal constant and high stiffness. The back plate is flat and the upper is paraboloid shaped. Each elementary cell has, in the lower plate, one circular hole permitting the ventilation of cell itself. The material used is the borosilicate Ohara E6. Different supporting systems have been analyzed from the mirror casting to the operative conditions, i.e.: supporting system during the cooling of the casting phase; supporting system for the handling after the casting phase and before the optical surface grinding and polishing; supporting system for the handling after the optical surface polishing and for maintenance; passive support system in non-operative condition; supporting system in operative condition. The stress checks carried out show that the values of the maximum principal tensile stresses are below 0.7 MPa for long times and/or stresses affecting large volumes, and are below 1.05 MPa for short times and small volumes. Optical performances in operative condition respect the specification.

  16. Extending the mirror neuron system model, II: what did I just do? A new role for mirror neurons.

    PubMed

    Bonaiuto, James; Arbib, Michael A

    2010-04-01

    A mirror system is active both when an animal executes a class of actions (self-actions) and when it sees another execute an action of that class. Much attention has been given to the possible roles of mirror systems in responding to the actions of others but there has been little attention paid to their role in self-actions. In the companion article (Bonaiuto et al. Biol Cybern 96:9-38, 2007) we presented MNS2, an extension of the Mirror Neuron System model of the monkey mirror system trained to recognize the external appearance of its own actions as a basis for recognizing the actions of other animals when they perform similar actions. Here we further extend the study of the mirror system by introducing the novel hypotheses that a mirror system may additionally help in monitoring the success of a self-action and may also be activated by recognition of one's own apparent actions as well as efference copy from one's intended actions. The framework for this computational demonstration is a model of action sequencing, called augmented competitive queuing, in which action choice is based on the desirability of executable actions. We show how this "what did I just do?" function of mirror neurons can contribute to the learning of both executability and desirability which in certain cases supports rapid reorganization of motor programs in the face of disruptions.

  17. On Empathy: The Mirror Neuron System and Art Education

    ERIC Educational Resources Information Center

    Jeffers, Carol S.

    2009-01-01

    This paper re/considers empathy and its implications for learning in the art classroom, particularly in light of relevant neuroscientific investigations of the mirror neuron system recently discovered in the human brain. These investigations reinterpret the meaning of perception, resonance, and connection, and point to the fundamental importance…

  18. The Mirror Neuron System: Grasping Others' Actions from Birth?

    ERIC Educational Resources Information Center

    Lepage, Jean-Francois; Theoret, Hugo

    2007-01-01

    In the adult human brain, the presence of a system matching the observation and the execution of actions is well established. This mechanism is thought to rely primarily on the contribution of so-called "mirror neurons", cells that are active when a specific gesture is executed as well as when it is seen or heard. Despite the wealth of evidence…

  19. Optical systems for synchrotron radiation. Lecture 2. Mirror systems

    SciTech Connect

    Howells, M.R.

    1986-02-01

    The process of reflection of VUV and x-radiation is summarized. The functions of mirrors in synchrotron beamlines are described, which include deflection, filtration, power absorption, formation of a real image, focusing, and collimation. Fabrication of optical surfaces for synchrotron radiation beamlines are described, and include polishing of a near spherical surface as well as bending a cylindrical surface to toroidal shape. The imperfections present in mirrors, aberrations and surface figure inaccuracy, are discussed. Calculation of the thermal load of a mirror in a synchrotron radiation beam and the cooling of the mirror are covered briefly. 50 refs., 7 figs. (LEW)

  20. Kirkpatrick-Baez mirrors to focus hard X-rays in two dimensions as fabricated, tested and installed at the Advanced Photon Source.

    PubMed

    Kujala, Naresh; Marathe, Shashidhara; Shu, Deming; Shi, Bing; Qian, Jun; Maxey, Evan; Finney, Lydia; Macrander, Albert; Assoufid, Lahsen

    2014-07-01

    The micro-focusing performance for hard X-rays of a fixed-geometry elliptical Kirkpatrick-Baez (K-B) mirrors assembly fabricated, tested and finally implemented at the micro-probe beamline 8-BM of the Advanced Photon Source is reported. Testing of the K-B mirror system was performed at the optics and detector test beamline 1-BM. K-B mirrors of length 80 mm and 60 mm were fabricated by profile coating with Pt metal to produce focal lengths of 250 mm and 155 mm for 3 mrad incident angle. For the critical angle of Pt, a broad bandwidth of energies up to 20 keV applies. The classical K-B sequential mirror geometry was used, and mirrors were mounted on micro-translation stages. The beam intensity profiles were measured by differentiating the curves of intensity data measured using a wire-scanning method. A beam size of 1.3 µm (V) and 1.2 µm (H) was measured with monochromatic X-rays of 18 keV at 1-BM. After installation at 8-BM the measured focus met the design requirements. In this paper the fabrication and metrology of the K-B mirrors are reported, as well as the focusing performances of the full mirrors-plus-mount set-up at both beamlines.

  1. Effect of synchrotron radiation on the advanced-fueled field-reversed mirror

    SciTech Connect

    Ho, S.K.

    1980-01-01

    The objective of this study is to investigate the effect of synchrotron radiation on the energy balance of advanced fuels in the field-reversed mirror (FRM) fusion device. The FRM configuration is simulated by the Hill's vortex model. The synchrotron radiant energy loss can be computed by adding the blackbody contribution (O < ..omega.. < ..omega..*) and the transparent contribution (..omega..* < ..omega.. < infinity), where ..omega.. is the radiation frequency and ..cap omega..* is the cutoff frequency.

  2. Cryogenic system for the mirror fusion test facility

    SciTech Connect

    VanSant, J.H.; Slack, D.S.; Nelson, R.L.

    1980-02-26

    The Mirror Fusion Test Facility (MFTF), currently being constructed at the Lawrence Livermore Laboratory, has large superconducting magnets, cryopanels, and supporting cryogenic equipment that will comprise one of the world's largest liquid helium (LHe) systems. The facility will provide mirror magnetic confinement for experimental fusion plasmas that will be approximately the same physical size as if in a conceptual fusion reactor. The cryogenic system typifies the magnitude and makeup of systems that will be used in future magnetic fusion reactors. Here we describe the LHe cryopumping and magnet systems. Principal components include a 3300 W helium refrigerator, 30,000 L LHe storage, a 1.5 MW (2000 hp) refrigerator compressor, 1100 m/sup 2/ of cryopanels, and a 420 MJ superconducting magnet system. Design features, method of operation, thermal protection, and helium recovery operations are discussed.

  3. Advanced MEMS systems for optical communication and imaging

    NASA Astrophysics Data System (ADS)

    Horenstein, M. N.; Stewart, J. B.; Cornelissen, S.; Sumner, R.; Freedman, D. S.; Datta, M.; Kani, N.; Miller, P.

    2011-06-01

    Optical communication and adaptive optics have emerged as two important uses of micro-electromechanical (MEMS) devices based on electrostatic actuation. Each application uses a mirror whose surface is altered by applying voltages of up to 300 V. Previous generations of adaptive-optic mirrors were large (~1 m) and required the use of piezoelectric transducers. Beginning in the mid-1990s, a new class of small MEMS mirrors (~1 cm) were developed. These mirrors are now a commercially available, mature technology. This paper describes three advanced applications of MEMS mirrors. The first is a mirror used for corona-graphic imaging, whereby an interferometric telescope blocks the direct light from a distant star so that nearby objects such as planets can be seen. We have developed a key component of the system: a 144-channel, fully-scalable, high-voltage multiplexer that reduces power consumption to only a few hundred milliwatts. In a second application, a MEMS mirror comprises part of a two-way optical communication system in which only one node emits a laser beam. The other node is passive, incorporating a retro-reflective, electrostatic MEMS mirror that digitally encodes the reflected beam. In a third application, the short (~100-ns) pulses of a commercially-available laser rangefinder are returned by the MEMS mirror as a digital data stream. Suitable low-power drive systems comprise part of the system design.

  4. Are mirror neurons the basis of speech perception? Evidence from five cases with damage to the purported human mirror system.

    PubMed

    Rogalsky, Corianne; Love, Tracy; Driscoll, David; Anderson, Steven W; Hickok, Gregory

    2011-01-01

    The discovery of mirror neurons in macaque has led to a resurrection of motor theories of speech perception. Although the majority of lesion and functional imaging studies have associated perception with the temporal lobes, it has also been proposed that the 'human mirror system', which prominently includes Broca's area, is the neurophysiological substrate of speech perception. Although numerous studies have demonstrated a tight link between sensory and motor speech processes, few have directly assessed the critical prediction of mirror neuron theories of speech perception, namely that damage to the human mirror system should cause severe deficits in speech perception. The present study measured speech perception abilities of patients with lesions involving motor regions in the left posterior frontal lobe and/or inferior parietal lobule (i.e., the proposed human 'mirror system'). Performance was at or near ceiling in patients with fronto-parietal lesions. It is only when the lesion encroaches on auditory regions in the temporal lobe that perceptual deficits are evident. This suggests that 'mirror system' damage does not disrupt speech perception, but rather that auditory systems are the primary substrate for speech perception.

  5. Coma of modified Gregorian and Cassegrainian mirror systems

    NASA Technical Reports Server (NTRS)

    Jones, R. T.

    1976-01-01

    The equivalence of the classical Newtonian, Cassegrainian, and Gregorian mirror systems with respect to the first two Seidel aberrations is rederived by means of a simple congruence. The effects of arbitrary small modifications of the two mirror systems are then studied and general formulas are derived for the effects of such modifications on the spherical aberration and coma. Spherical aberration is corrected to the third order if the amount of glass removed from one surface is replaced at the corresponding zone of the other surface. Modifications in which one surface is made spherical while the other is adjusted to eliminate spherical aberration result in large increases of coma for systems having the usual amplifying ratios.

  6. Overview and Recent Accomplishments of Advanced Mirror Technology Development Phase 2 (AMTD-2)

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2015-01-01

    AMTD uses a science-driven systems engineering approach to define & execute a long-term strategy to mature technologies necessary to enable future large aperture space telescopes. Because we cannot predict the future, we are pursuing multiple technology paths including monolithic & segmented mirrors. Assembled outstanding team from academia, industry & government; experts in science & space telescope engineering. Derived engineering specifications from science measurement needs & implementation constraints. Maturing 6 critical technologies required to enable 4 to 8 meter UVOIR space telescope mirror assemblies for both general astrophysics & ultra-high contrast exoplanet imaging. AMTD achieving all its goals & accomplishing all its milestones.

  7. Overview and Recent Accomplishments of Advanced Mirror Technology Development (AMTD) for Very Large Space Telescopes

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2013-01-01

    AMTD uses a science-driven systems engineering approach to define & execute a long-term strategy to mature technologies necessary to enable future large aperture space telescopes. Because we cannot predict the future, we are pursuing multiple technology paths including monolithic & segmented mirrors. Assembled outstanding team from academia, industry & government; experts in science & space telescope engineering. Derived engineering specifications from science measurement needs & implementation constraints. Maturing 6 critical technologies required to enable 4 to 8 meter UVOIR space telescope mirror assemblies for both general astrophysics & ultra-high contrast exoplanet imaging. AMTD achieving all its goals & accomplishing all its milestones.

  8. MHD-Stabilization of Axisymmetric Mirror Systems Using Pulsed ECRH

    SciTech Connect

    Post, R F

    2009-11-20

    This paper, part of a continuing study of means for the stabilization of MHD interchange modes in axisymmertric mirror-based plasma confinement systems, is aimed at a preliminary look at a technique that would employ a train of plasma pressure pulses produced by ECRH to accomplish the stabilization. The purpose of using sequentially pulsed ECRH rather than continuous-wave ECRH is to facilitate the localization of the heated-electron plasma pulses in regions of the magnetic field with a strong positive field-line curvature, e. g. in the 'expander' region of the mirror magnetic field, outside the outermost mirror, or in other regions of the field with positive field-line curvature. The technique proposed, of the class known as 'dynamic stabilization,' relies on the time-averaged effect of plasma pressure pulses generated in regions of positive field-line curvature to overcome the destabilizing effect of plasma pressure in regions of negative field-line curvature within the confinement region. As will also be discussed in the paper, the plasma pulses, when produced in regions of the confining having a negative gradient, create transient electric potentials of ambipolar origin, an effect that was studied in 1964 in The PLEIDE experiment in France. These electric fields preserve the localization of the hot-electron plasma pulses for a time determined by ion inertia. It is suggested that it may be possible to use this result of pulsed ECRH not only to help to stabilize the plasma but also to help plug mirror losses in a manner similar to that employed in the Tandem Mirror.

  9. Automated interferometric alignment system for paraboloidal mirrors

    DOEpatents

    Maxey, L. Curtis

    1993-01-01

    A method is described for a systematic method of interpreting interference fringes obtained by using a corner cube retroreflector as an alignment aid when aigning a paraboloid to a spherical wavefront. This is applicable to any general case where such alignment is required, but is specifically applicable in the case of aligning an autocollimating test using a diverging beam wavefront. In addition, the method provides information which can be systematically interpreted such that independent information about pitch, yaw and focus errors can be obtained. Thus, the system lends itself readily to automation. Finally, although the method is developed specifically for paraboloids, it can be seen to be applicable to a variety of other aspheric optics when applied in combination with a wavefront corrector that produces a wavefront which, when reflected from the correctly aligned aspheric surface will produce a collimated wavefront like that obtained from the paraboloid when it is correctly aligned to a spherical wavefront.

  10. Automated interferometric alignment system for paraboloidal mirrors

    DOEpatents

    Maxey, L.C.

    1993-09-28

    A method is described for a systematic method of interpreting interference fringes obtained by using a corner cube retroreflector as an alignment aid when aligning a paraboloid to a spherical wavefront. This is applicable to any general case where such alignment is required, but is specifically applicable in the case of aligning an autocollimating test using a diverging beam wavefront. In addition, the method provides information which can be systematically interpreted such that independent information about pitch, yaw and focus errors can be obtained. Thus, the system lends itself readily to automation. Finally, although the method is developed specifically for paraboloids, it can be seen to be applicable to a variety of other aspheric optics when applied in combination with a wavefront corrector that produces a wavefront which, when reflected from the correctly aligned aspheric surface will produce a collimated wavefront like that obtained from the paraboloid when it is correctly aligned to a spherical wavefront. 14 figures.

  11. Field Experience with 3-Sun Mirror Module Systems

    SciTech Connect

    Fraas, Dr. Lewis; Avery, James E.; Huang, H,; Minkin, Leonid M; Fraas, J. X.; Maxey, L Curt; Gehl, Anthony C

    2008-01-01

    JX Crystals 3-sun PV mirror modules have now been operating in four separate systems in the field for up to 2 years. Two post-mounted 2-axis tracking arrays of 12 modules each were installed at the Shanghai Flower Park in April of 2006. Then 672 modules were installed in a 100 kW array on N-S horizontal beam trackers at the Shanghai Flower Port in November of 2006. Finally, sets of 4 modules were installed on azimuth-tracking carousels on buildings at the Oak Ridge National Lab and at the U. of Nevada in Las Vegas in late 2007. All of these modules in each of these systems are still operating at their initial power ratings. No degradation in performance has been observed. The benefit of these 3-sun PV mirror modules is that they use 1/3 of the silicon single-crystal cell material in comparison to traditional planar modules. Since aluminum mirrors are much cheaper than high-purity single-crystal silicon-cells, these modules and systems should be much lower in cost when manufactured in high volume.

  12. Primary mirror back surface shape research of GEO laser communication system

    NASA Astrophysics Data System (ADS)

    Liu, Weida; Zhang, Li-zhong; Meng, Li-xin

    2015-11-01

    The research of laser communication system primary mirror deformation caused by back surface shape variation was done in this paper. The usual mirror back surface shapes were sphere, double arch, flat and biconcave shape and so on. Based on the four shape mirror, with the center hole rim support pattern, the four shape mirror temperature distribution equation was inferred by thermal elastic theory, deformation are compared in 1-5℃ radius direction temperature difference, in the case of minor weight gap and equal maximum thickness. As a result, the deformation of sphere back surface shape mirror is minimal. So sphere back surface shape is fit for the primary mirror.

  13. Variable Curvature Mirrors for ELT Laser Guide Star refocusing systems

    NASA Astrophysics Data System (ADS)

    Challita, Zalpha; Hugot, Emmanuel; Ferrari, Marc; Madec, Fabrice; Le Mignant, David; Cuby, Jean-Gabriel

    2011-09-01

    The future generation of Extremely Large Telescopes will require a complex combination of technologies for adaptive optics (AO) systems assisted by laser guide stars (LGS). In this context, LGS defocusing is one of the system issues that can be tackled using active refocusing mirrors such as Variable Curvature Mirrors (VCM). Indeed, the distance from the LGS spot to the telescope pupil ranges from about 80 to 200 km, depending on the Sodium layer altitude and the elevation of the telescope, and induces a large defocusing at the LGS wave-front sensor focal plane. To compensate for that, we propose an original concept including a VCM specifically designed to keep a focused spot on the wave-front sensor: the mirror is made of a thin meniscus bend using a pressure applied on its back face. Due to the large defocusing, the LGS-VCM must be able to change its shape from F/12.5 to F/5, leading to more than 1 mm sag. The VCM benefits of a specific shape with a variable radial thickness distribution, allowing keeping an optical quality better than λ/5 over this very large range of deformation. The work presented here details the analytical development leading to the specific geometry of the active component, the results of finite element analysis and the expected performances in terms of surface error versus the range of refocalisation. Two prototypes have been manufactured to compare the real behaviour of the mirror and the simulations data. Results obtained on the prototypes show that the deformation of the VCM is very close to the simulation, and leads to a realistic concept.

  14. Steerable diffraction limited line illumination system using deformable mirror

    NASA Astrophysics Data System (ADS)

    Taniguchi, Koichi; Kim, Dae Wook; Shimura, Kei; Burge, James H.

    2013-09-01

    Many scientific and industrial applications often require high performance optical systems utilizing spatially shaped illumination patterns of laser beams. Precisely shaped line illumination can be used for various line scanning systems or surface inspection devices. In order to achieve the highest resolution or superior signal to noise ratio limited by the fundamental theory, a diffraction limited illumination optical system (e.g. <0.8 Strehl ratio) gives the narrowest illumination line width determined by the system's NA (Numerical Aperture) value. For high precision and in-factory industrial applications, the Diffraction Limited Line Illumination (DLLI) needs to be controlled in three dimensional space rapidly as the target object under the illumination may not be always aligned with respect to the illumination system. A steerable DLLI system with three degrees of freedom (i.e. axial displacement, rotation, and tilt) is developed using an adaptive optics system. By electronically controlling the Zernike based surface shapes of the deformable mirror, the DLLI in free space is actively positioned and oriented with high accuracy. The geometrical optics based mathematical model to control the Zernike modes of the deformable mirror and the performance of a bench-top proof-ofconcept system will be presented with experimental data and analysis results.

  15. Performance Reports: Mirror alignment system performance prediction comparison between SAO and EKC

    NASA Technical Reports Server (NTRS)

    Tananbaum, H. D.; Zhang, J. P.

    1994-01-01

    The objective of this study is to perform an independent analysis of the residual high resolution mirror assembly (HRMA) mirror distortions caused by force and moment errors in the mirror alignment system (MAS) to statistically predict the HRMA performance. These performance predictions are then compared with those performed by Kodak to verify their analysis results.

  16. Production of the 4.26 m ZERODUR mirror blank for the Advanced Technology Solar telescope (ATST)

    NASA Astrophysics Data System (ADS)

    Jedamzik, Ralf; Werner, Thomas; Westerhoff, Thomas

    2014-07-01

    The Daniel K. Inouye Solar Telescope (DKIST, formerly the Advanced Technology Solar Telescope, ATST) will be the most powerful solar telescope in the world. It is currently being built by the Association of Universities for Research in Astronomy (AURA) in a height of 3000 m above sea level on the mountain Haleakala of Maui, Hawaii. The primary mirror blank of diameter 4.26 m is made of the extremely low thermal expansion glass ceramic ZERODUR® of SCHOTT AG Advanced Optics. The DKIST primary mirror design is extremely challenging. With a mirror thickness of only 78 to 85 mm it is the smallest thickness ever machined on a mirror of 4.26 m in diameter. Additionally the glassy ZERODUR® casting is one of the largest in size ever produced for a 4 m class ZERODUR® mirror blank. The off axis aspherical mirror surface required sophisticated grinding procedures to achieve the specified geometrical tolerance. The small thickness of about 80 mm required special measures during processing, lifting and transport. Additionally acid etch treatment was applied to the convex back-surface and the conical shaped outer diameter surface to improve the strength of the blank. This paper reports on the challenging tasks and the achievements on the material property and dimensional specification parameter during the production of the 4.26 m ZERODUR® primary mirror blank for AURA.

  17. Metrology of a mirror at the Advanced Photon Source : comparison between optical and x-ray measurements.

    SciTech Connect

    Assoufid, L.

    1998-10-14

    This paper describes metrology of a vertically focusing mirror on the bending magnet beamline in sector-1 of the Advanced Photon Source, Argonne National Laboratory. The mirror was evaluated using measurements from both an optical long trace profiler and x-rays. Slope error profiles obtained with the two methods were compared and were found to be in a good agreement. Further comparisons were made between x-ray measurements and results from the SHADOW ray-tracing code.

  18. Measuring change in health-system pharmacy over 50 years: "reflecting" on the mirror, part I.

    PubMed

    Weber, Robert J; Stevenson, James; Ng, Christine; White, Sara

    2013-12-01

    The Director's Forum guides pharmacy leaders in establishing patient-centered services in hospitals and health systems. August 2013 marked the 50th anniversary of the publication of the Mirror to Hospital Pharmacy, which was a comprehensive study of hospital pharmacy services in the United States. This iconic textbook was co-authored by Donald Francke, Clifton J. Latiolais, Gloria N. Francke, and Norman Ho. The Mirror profiled hospital pharmacy of the 1950s and established goals for the profession in 6 paradigms: (1) professional philosophy and ethics, (2) scientific and technical expansion of health-system pharmacy, (3) development of administrative and managerial acumen, (4) increased practice competence, (5) wage and salary compensation commensurate with professional responsibilities, and (6) health-system pharmacy as a vehicle for advancing the profession as a whole. This article critically reviews the profession's progress on the first 3 goals; an article in the January 2014 issue of Hospital Pharmacy will review the final 3 goals. An understanding of the profession's progress on these goals since the seminal work of the Mirror provides directors of pharmacy a platform from which to develop strategies to enhance patient-centered pharmacy services.

  19. Measuring Change in Health-System Pharmacy Over 50 Years: "Reflecting" on the Mirror, Part II.

    PubMed

    Weber, Robert J; Stevenson, James G; White, Sara J

    2014-01-01

    The Director's Forum guides pharmacy leaders in establishing patient-centered services in hospitals and health systems. 2013 marked the 50th anniversary of the publication of the Mirror to Hospital Pharmacy, which was a comprehensive study of hospital pharmacy services in the United States. This iconic textbook was co-authored by Donald Francke, Clifton J. Latiolais, Gloria N. Francke, and Norman Ho. The Mirror's results profiled hospital pharmacy of the 1950s; these results established goals for the profession in 6 paradigms: (1) professional philosophy and ethics; (2) scientific and technical expansion of health-system pharmacy; (3) development of administrative and managerial acumen; (4) increased practice competence; (5) wage and salary commensurate with professional responsibilities; and (6) health-system pharmacy as a vehicle for advancing the profession as a whole. This article critically reviews our progress on the last of 3 goals. An understanding of the profession's progress on these goals since the seminal work of the Mirror provides directors of pharmacy a platform from which to develop strategies to enhance patient-centered pharmacy services.

  20. Stimulated Brillouin scattering mirror system, high power laser and laser peening method and system using same

    DOEpatents

    Dane, C. Brent; Hackel, Lloyd; Harris, Fritz B.

    2007-04-24

    A laser system, such as a master oscillator/power amplifier system, comprises a gain medium and a stimulated Brillouin scattering SBS mirror system. The SBS mirror system includes an in situ filtered SBS medium that comprises a compound having a small negative non-linear index of refraction, such as a perfluoro compound. An SBS relay telescope having a telescope focal point includes a baffle at the telescope focal point which blocks off angle beams. A beam splitter is placed between the SBS mirror system and the SBS relay telescope, directing a fraction of the beam to an alternate beam path for an alignment fiducial. The SBS mirror system has a collimated SBS cell and a focused SBS cell. An adjustable attenuator is placed between the collimated SBS cell and the focused SBS cell, by which pulse width of the reflected beam can be adjusted.

  1. Advanced drilling systems study

    SciTech Connect

    Pierce, K.G.; Livesay, B.J.

    1995-03-01

    This work was initiated as part of the National Advanced Drilling and Excavation Technologies (NADET) Program. It is being performed through joint finding from the Department of Energy Geothermal Division and the Natural Gas Technology Branch, Morgantown Energy Technology Center. Interest in advanced drilling systems is high. The Geothermal Division of the Department of Energy has initiated a multi-year effort in the development of advanced drilling systems; the National Research Council completed a study of drilling and excavation technologies last year; and the MIT Energy Laboratory recently submitted a proposal for a national initiative in advanced drilling and excavation research. The primary reasons for this interest are financial. Worldwide expenditures on oil and gas drilling approach $75 billion per year. Also, drilling and well completion account for 25% to 50% of the cost of producing electricity from geothermal energy. There is incentive to search for methods to reduce the cost of drilling. Work on ideas to improve or replace rotary drilling technology dates back at least to the 1930`s. There was a significant amount of work in this area in the 1960`s and 1970`s; and there has been some continued effort through the 1980`s. Undoubtedly there are concepts for advanced drilling systems that have yet to be studied; however, it is almost certain that new efforts to initiate work on advanced drilling systems will build on an idea or a variation of an idea that has already been investigated. Therefore, a review of previous efforts coupled with a characterization of viable advanced drilling systems and the current state of technology as it applies to those systems provide the basis for the current study of advanced drilling.

  2. Design and analysis of large spaceborne light-weighted primary mirror and its support system

    NASA Astrophysics Data System (ADS)

    Yan, Yong; Jin, Guang; Yang, Hong-bo

    2007-12-01

    With the development of the resolution of spaceborne remote sensor, the diameter of the primary mirror of spaceborne telescope becomes larger and larger. The distortion of primary mirror which is influenced by the mirror material, structure, self-weight, support system and temperature environment affects optical image quality finally. In this paper, an on-axis TMA high-resolution Cassegrain optical payload with a primary mirror whose diameter is φ 650mm was designed and the effects of the influence factors of the distortion acts on the on-axis TMA optical system primary mirror had been analyzed by means of Finite Element Analysis. During work, the technology of the primary mirror design had been summarized and general consideration of the primary mirror design technology also had been described at the same time. Considering the telescope manufacture and work station, a reasonable and optimal structure of the primary mirror sub-assembly is taken finally. In the end, the distortion of the primary mirror during its fabrication station and work station had been analyzed by integrated Finite Element Analysis Method. The results implicated the synthesis profile error (P-V value) for the primary mirror is less than λ/10 and all the indexes of the primary mirror satisfy the requirements of the optical system.

  3. Communications system using a mirror kept in outer space by electromagnetic radiation pressure

    DOEpatents

    Csonka, Paul L.

    1981-01-01

    A method and system are described for transmitting electromagnetic radiation by using a communications mirror located between about 100 kilometers and about 200 kilometers above ground. The communications mirror is kept aloft above the atmosphere by the pressure of the electromagnetic radiation which it reflects, and which is beamed at the communications mirror by a suitably constructed transmitting antenna on the ground. The communications mirror will reflect communications, such as radio, radar, or television waves up to about 1,100 kilometers away when the communications mirror is located at a height of about 100 kilometers.

  4. Advanced Monitoring systems initiative

    SciTech Connect

    R.J. Venedam; E.O. Hohman; C.F. Lohrstorfer; S.J. Weeks; J.B. Jones; W.J. Haas

    2004-09-30

    The Advanced Monitoring Systems Initiative (AMSI) actively searches for promising technologies and aggressively moves them from the research bench into DOE/NNSA end-user applications. There is a large unfulfilled need for an active element that reaches out to identify and recruit emerging sensor technologies into the test and evaluation function. Sensor research is ubiquitous, with the seeds of many novel concepts originating in the university systems, but at present these novel concepts do not move quickly and efficiently into real test environments. AMSI is a widely recognized, self-sustaining ''business'' accelerating the selection, development, testing, evaluation, and deployment of advanced monitoring systems and components.

  5. The Large Binocular Telescope primary mirror support control system description and current performance results

    NASA Astrophysics Data System (ADS)

    Ashby, David S.; Kern, Jonathan; Hill, John M.; Davison, Warren B.; Cuerden, Brian; Brynnel, Joar G.; Biddick, Chris; Duffek, Kenneth

    2008-07-01

    The Large Binocular Telescope (LBT) is built around two lightweight borosilicate honeycomb mirrors which, at 8.4 meters in diameter, are the largest operational examples of this technology. Since the mirrors are relatively stiff, the LBT mirror support system relies on passive position control and active force control. Passive position control is performed by six extendable hardpoints organized as a truncated hexapod, which may be positioned as required by the active optics control loop. The hardpoints rely on their axial stiffness to maintain the mirror position against residual external disturbances. The active force control system minimizes the force exerted by the hardpoints on the glass. Additionally, the axial component of the nominally uniform active support forces can be perturbed to distort the mirror as required by the active optics control loop. Because of the relatively large CTE of borosilicate glass, the differential temperature of the mirror is critical. Thus, the force control system must support a 16 metric ton mirror using less than 100 Watts of electrical power. The authors present a description of the primary mirror support system as implemented at the LBT. Initial stability problems made the mirrors nearly unusable in freezing temperatures. The authors explain the reason for this instability and describe the solutions implemented. Data demonstrating the current performance of the primary mirror support system are also presented.

  6. Testing Dark Energy with the Advanced Liquid-Mirror Probe of Asteroids, Cosmology and Astrophysics

    NASA Astrophysics Data System (ADS)

    LoVerde, M.; Corasaniti, P. S.; Crotts, A.; Blake, C.

    2006-06-01

    The Advanced Liquid-Mirror Probe of Asteroids, Cosmology and Astrophysics (ALPACA) is a proposed 8-meter liquid mirror telescope surveying ˜ 1000 deg2 of the southern-hemisphere sky. It will be a remarkably simple and inexpensive telescope that will nonetheless deliver a powerful sample of optical data for studying dark energy. The bulk of the cosmological data consists of nightly, high signal-to-noise, multiband light curves of SN Ia. At the end of the three-year run ALPACA is expected to collect ˜ 100,000 SN Ia up to z ˜ 1. This will allow accurate calibration of the standard-candle relation and reduce the systematic uncertainties. The survey will also provide several other datasets such as the detection of baryon acoustic oscillations in the matter power spectrum and shear weak lensing measurements. In this preliminary analysis we forecast constraints on dark energy parameters from SN Ia and baryon acoustic oscillations. The combination of these two datasets will provide competitive constraints on the dark energy parameters with minimal prior assumptions. Further studies are needed to address the accuracy of weak lensing measurements.

  7. Testing dark energy with the Advanced Liquid-mirror Probe of Asteroids, Cosmology and Astrophysics

    NASA Astrophysics Data System (ADS)

    Corasaniti, Pier Stefano; LoVerde, Marilena; Crotts, Arlin; Blake, Chris

    2006-06-01

    The Advanced Liquid-mirror Probe of Asteroids, Cosmology and Astrophysics (ALPACA) is a proposed 8-m liquid-mirror telescope surveying ~1000deg2 of the Southern hemisphere sky. It will be a remarkably simple and inexpensive telescope that none the less will deliver a powerful sample of optical data for studying dark energy. The bulk of the cosmological data consist of nightly, high signal-to-noise ratio, multiband light curves of Type Ia supernovae (SNe Ia). At the end of the 3-yr run, ALPACA is expected to collect >~100000 SNe Ia up to z ~ 1. This will allow us to reduce present systematic uncertainties affecting the standard-candle relation. The survey will also provide several other data sets such as the detection of baryon acoustic oscillations in the matter power spectrum and shear weak-lensing measurements. In this preliminary analysis, we forecast constraints on dark energy parameters from SNe Ia and baryon acoustic oscillations. The combination of these two data sets will provide competitive constraints on the dark energy parameters under minimal prior assumptions. Further studies are needed to address the accuracy of weak-lensing measurements.

  8. Final Report Advanced Quasioptical Launcher System

    SciTech Connect

    Jeffrey Neilson

    2010-04-30

    This program developed an analytical design tool for designing antenna and mirror systems to convert whispering gallery RF modes to Gaussian or HE11 modes. Whispering gallery modes are generated by gyrotrons used for electron cyclotron heating of fusion plasmas in tokamaks. These modes cannot be easily transmitted and must be converted to free space or waveguide modes compatible with transmission line systems.This program improved the capability of SURF3D/LOT, which was initially developed in a previous SBIR program. This suite of codes revolutionized quasi-optical launcher design, and this code, or equivalent codes, are now used worldwide. This program added functionality to SURF3D/LOT to allow creating of more compact launcher and mirror systems and provide direct coupling to corrugated waveguide within the vacuum envelope of the gyrotron. Analysis was also extended to include full-wave analysis of mirror transmission line systems. The code includes a graphical user interface and is available for advanced design of launcher systems.

  9. Toward high-dynamic active mirrors for LGS refocusing systems

    NASA Astrophysics Data System (ADS)

    Hugot, Emmanuel; Madec, Fabrice; Vives, Sébastien; Ferrari, Marc; Le Mignant, David; Cuby, Jean Gabriel

    2010-07-01

    In the frame of the E-ELT-EAGLE instrument phase A studies, we designed a convex VCM able to compensate for the focus variation on the Laser Guide Star (LGS) wavefront sensor, due to the elevation of the telescope and the fixed sodium layer altitude. We present an original optical design including this active convex mirror, providing a large sag variation on a spherical surface with a 120mm clear aperture, with an optical quality better than lambda/5 RMS up to 820μm of sag and better than lambda/4 RMS up to 1000μm of sag. Finite element analysis (FEA) allowed an optimisation of the mirror's variable thickness distribution to compensate for geometrical and material non linearity. Preliminary study of the pre-stressing has also been performed by FEA, showing that a permanent deformation remains after removal of the loads. Results and comparison with the FEA are presented in the article of F.Madec et al (AS10-7736-119, this conference), with an emphasis on the system approach.

  10. Embodied simulation: from mirror neuron systems to interpersonal relations.

    PubMed

    Gallese, Vittorio

    2007-01-01

    A direct form of 'experiential understanding' of others is achieved by modelling their behaviours as intentional experiences on the basis of the equivalence between what the others do and feel and what we do and feel. This modelling mechanism is embodied simulation. By means of embodied simulation we do not just 'see' an action, an emotion, or a sensation. Side by side with the sensory description of the observed social stimuli, internal representations of the body states associated with actions, emotions, and sensations are evoked in the observer, as if he/she would be doing a similar action or experiencing a similar emotion or sensation. Mirror neurons are likely the neural correlate of this mechanism. The mirror neuron matching systems map the different intentional relations in a compressed fashion, which is neutral about the specific quality or identity of the agentive/subjective parameter. By means of a shared neural state realized in two different bodies that nevertheless obey to the same functional rules, the 'objectual other' becomes 'another self'.

  11. Advanced turbine systems program

    SciTech Connect

    Wilkes, C.; Mukavetz, D.W.; Knickerbocker, T.K.; Ali, S.A.

    1992-01-01

    In accordance with the goals of the DOE program, improvements in the gas turbine are the primary focus of Allison activity during Phase I. To this end Allison conducted a survey of potentially applicable gas turbine cycles and selected the advanced combined cycle as reference system. Extensive analysis of two versions of the advanced combined cycle was performed against the requirement for a 60% thermal efficiency (LHV) utility-sized, natural gas fired system. This analysis resulted in technology requirements for this system. Additional analysis determined emissions potential for the system, established a coal-fueled derivative system and a commercialization plan. This report deals with the technical requirements for a system that meets the thermal efficiency goal. Allison initially investigated four basic thermodynamic cycles: Humid air turbine, intercalate-recuperated systems, advanced combined cycle, chemically recuperated cycle. Our survey and cycle analysis indicated that au had the potential of reaching 60% thermal efficiency. We also concluded that engine hot section technology would be a critical technology regardless of which cycle was chosen. Based on this result Allison chose to concentrate on the advanced combined cycle. This cycle is well known and understood by the utility turbine user community and is therefore likely to be acceptable to users.

  12. Advanced turbine systems program

    SciTech Connect

    Wilkes, C.; Mukavetz, D.W.; Knickerbocker, T.K.; Ali, S.A.

    1992-12-31

    In accordance with the goals of the DOE program, improvements in the gas turbine are the primary focus of Allison activity during Phase I. To this end Allison conducted a survey of potentially applicable gas turbine cycles and selected the advanced combined cycle as reference system. Extensive analysis of two versions of the advanced combined cycle was performed against the requirement for a 60% thermal efficiency (LHV) utility-sized, natural gas fired system. This analysis resulted in technology requirements for this system. Additional analysis determined emissions potential for the system, established a coal-fueled derivative system and a commercialization plan. This report deals with the technical requirements for a system that meets the thermal efficiency goal. Allison initially investigated four basic thermodynamic cycles: Humid air turbine, intercalate-recuperated systems, advanced combined cycle, chemically recuperated cycle. Our survey and cycle analysis indicated that au had the potential of reaching 60% thermal efficiency. We also concluded that engine hot section technology would be a critical technology regardless of which cycle was chosen. Based on this result Allison chose to concentrate on the advanced combined cycle. This cycle is well known and understood by the utility turbine user community and is therefore likely to be acceptable to users.

  13. Experience with wavefront sensor and deformable mirror interfaces for wide-field adaptive optics systems

    NASA Astrophysics Data System (ADS)

    Basden, A. G.; Atkinson, D.; Bharmal, N. A.; Bitenc, U.; Brangier, M.; Buey, T.; Butterley, T.; Cano, D.; Chemla, F.; Clark, P.; Cohen, M.; Conan, J.-M.; de Cos, F. J.; Dickson, C.; Dipper, N. A.; Dunlop, C. N.; Feautrier, P.; Fusco, T.; Gach, J. L.; Gendron, E.; Geng, D.; Goodsell, S. J.; Gratadour, D.; Greenaway, A. H.; Guesalaga, A.; Guzman, C. D.; Henry, D.; Holck, D.; Hubert, Z.; Huet, J. M.; Kellerer, A.; Kulcsar, C.; Laporte, P.; Le Roux, B.; Looker, N.; Longmore, A. J.; Marteaud, M.; Martin, O.; Meimon, S.; Morel, C.; Morris, T. J.; Myers, R. M.; Osborn, J.; Perret, D.; Petit, C.; Raynaud, H.; Reeves, A. P.; Rousset, G.; Sanchez Lasheras, F.; Sanchez Rodriguez, M.; Santos, J. D.; Sevin, A.; Sivo, G.; Stadler, E.; Stobie, B.; Talbot, G.; Todd, S.; Vidal, F.; Younger, E. J.

    2016-06-01

    Recent advances in adaptive optics (AO) have led to the implementation of wide field-of-view AO systems. A number of wide-field AO systems are also planned for the forthcoming Extremely Large Telescopes. Such systems have multiple wavefront sensors of different types, and usually multiple deformable mirrors (DMs). Here, we report on our experience integrating cameras and DMs with the real-time control systems of two wide-field AO systems. These are CANARY, which has been operating on-sky since 2010, and DRAGON, which is a laboratory AO real-time demonstrator instrument. We detail the issues and difficulties that arose, along with the solutions we developed. We also provide recommendations for consideration when developing future wide-field AO systems.

  14. Advanced Solar Power Systems

    NASA Technical Reports Server (NTRS)

    Atkinson, J. H.; Hobgood, J. M.

    1984-01-01

    The Advanced Solar Power System (ASPS) concentrator uses a technically sophisticated design and extensive tooling to produce very efficient (80 to 90%) and versatile energy supply equipment which is inexpensive to manufacture and requires little maintenance. The advanced optical design has two 10th order, generalized aspheric surfaces in a Cassegrainian configuration which gives outstanding performance and is relatively insensitive to temperature changes and wind loading. Manufacturing tolerances also have been achieved. The key to the ASPS is the direct absorption of concentrated sunlight in the working fluid by radiative transfers in a black body cavity. The basic ASPS design concepts, efficiency, optical system, and tracking and focusing controls are described.

  15. CONDOR Advanced Visionics System

    NASA Astrophysics Data System (ADS)

    Kanahele, David L.; Buckanin, Robert M.

    1996-06-01

    The Covert Night/Day Operations for Rotorcraft (CONDOR) program is a collaborative research and development program between the governments of the United States and the United Kingdom of Great Britain and Northern Ireland to develop and demonstrate an advanced visionics concept coupled with an advanced flight control system to improve rotorcraft mission effectiveness during day, night, and adverse weather conditions in the Nap- of-the-Earth environment. The Advanced Visionics System for CONDOR is the flight- ruggedized head mounted display and computer graphics generator with the intended use of exploring, developing, and evaluating proposed visionic concepts for rotorcraft including; the application of color displays, wide field-of-view, enhanced imagery, virtual displays, mission symbology, stereo imagery, and other graphical interfaces.

  16. Systems and methods for mirror mounting with minimized distortion

    NASA Technical Reports Server (NTRS)

    Antonille, Scott R. (Inventor); Wallace, Thomas E. (Inventor); Content, David A. (Inventor); Wake, Shane W. (Inventor)

    2012-01-01

    A method for mounting a mirror for use in a telescope includes attaching the mirror to a plurality of adjustable mounts; determining a distortion in the mirror caused by the plurality adjustable mounts, and, if the distortion is determined to be above a predetermined level: adjusting one or more of the adjustable mounts; and determining the distortion in the mirror caused by the adjustable mounts; and in the event the determined distortion is determined to be at or below the predetermined level, rigidizing the adjustable mounts.

  17. Advanced Distribution Management System

    NASA Astrophysics Data System (ADS)

    Avazov, Artur R.; Sobinova, Liubov A.

    2016-02-01

    This article describes the advisability of using advanced distribution management systems in the electricity distribution networks area and considers premises of implementing ADMS within the Smart Grid era. Also, it gives the big picture of ADMS and discusses the ADMS advantages and functionalities.

  18. Computer-aided alignment of off-axis three-mirror imaging spectrometer system

    NASA Astrophysics Data System (ADS)

    Gong, Dun; Wang, Hong; Tian, Tie-yin

    2013-08-01

    The space camera is one of the most advanced optical equipments in obtaining earth surface information from space. With the development of the optical design, manufacture and alignment technology, the performance of the optical camera is moving forward quickly. In spaceto- ground remote sensing field, the resolution of ground remote sensing images have become higher and higher. Off-axis three-mirror system becomes an advanced optical system structure of space camera at present , because of its merits of large field, long focal length, no obstruction, high modulated transfer function, wide spectrum, good image quality, small cubage and light weight, etc. As it is difficult to align and test, the alignment of off-axis three mirror system is timeconsuming, so it is important and necessary of studying the computer-aided alignment of the complex optical system. Aiming at cutting the time of alignment, Computer-aided alignment technology is applied to this system. According to relation between fringe Zernike coefficient and Seidel aberration, wavefront aberration in the exit pupil of optical system is instead with fringe Zernike coefficient. A series of Zernike coefficient expressing the incorrect parameters of system are obtained by using multi-fields ZYGO interferometer auto-collimating interference test, which are transformed into geometric aberrations as the corrected object. Incorrect parameters of the system are determined by sensitivity matrix resulted from optical design software. These incorrect parameters are defined to be variables; the Zernike coefficient are defined to be the optimized target in merit function. The system is optimized by applying optical design software to receive the incorrect parameters result. Consequently, the adjusted result is brought into the optical design software to verify the right selection of incorrect parameters. The practical experiments are also given, result with RMS value lower than 0.04λ is acquired by using this

  19. Advanced Microturbine Systems

    SciTech Connect

    Lindberg, Laura

    2005-04-29

    Dept. of Energy (DOE) Cooperative Agreement DE-FC02-00-CH11061 was originally awarded to Honeywell International, Inc. Honeywell Power Systems Inc. (HPSI) division located in Albuquerque, NM in October 2000 to conduct a program titled Advanced Microturbine Systems (AMS). The DOE Advanced Microturbines Systems Program was originally proposed as a five-year program to design and develop a high efficiency, low emissions, durable microturbine system. The period of performance was to be October 2000 through September 2005. Program efforts were underway, when one year into the program Honeywell sold the intellectual property of Honeywell Power Systems Inc. and HPSI ceased business operations. Honeywell made an internal decision to restructure the existing program due to the HPSI shutdown and submitted a formal request to DOE on September 24, 2001 to transfer the Cooperative Agreement to Honeywell Engines, Systems and Services (HES&S) in Phoenix, AZ in order to continue to offer support for DOE's Advanced Microturbine Program. Work continued on the descoped program under Cooperative Agreement No. DE-FC26-00-CH11061 and has been completed.

  20. JWST Mirror Technology Development Results

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2007-01-01

    Mirror technology is a critical enabling capability for the James Webb Space Telescope (JWST). JWST requires a Primary Mirror Segment Assembly (PMSA) that can survive launch, deploy and align itself to form a 25 square meter collecting area 6.5 meter diameter primary mirror with a 131 nm rms wavefront error at temperatures less than 50K and provide stable optical performance. At the inception of JWST in 1996, such a capability did not exist. A highly successful technology development program was initiated including the Sub-scale Beryllium Mirror Demonstrator (SBMD) and Advanced Mirror System Demonstrator (AMSD) projects. These projects along with flight program activities have matured and demonstrated mirror technology for JWST. Directly traceable prototypes or flight hardware has been built, tested and operated in a relevant environment. This paper summarizes that technology development effort.

  1. Advanced dive monitoring system.

    PubMed

    Sternberger, W I; Goemmer, S A

    1999-01-01

    The US Navy supports deep diving operations with a variety of mixed-gas life support systems. A systems engineering study was conducted for the Naval Experimental Dive Unit (Panama City, FL) to develop a concept design for an advanced dive monitoring system. The monitoring system is intended primarily to enhance diver safety and secondarily to support diving medicine research. Distinct monitoring categories of diver physiology, life support system, and environment are integrated in the monitoring system. A system concept is proposed that accommodates real-time and quantitative measurements, noninvasive physiological monitoring, and a flexible and expandable implementation architecture. Human factors and ergonomic design considerations have been emphasized to assure that there is no impact on the diver's primary mission. The Navy has accepted the resultant system requirements and the basic design concept. A number of monitoring components have been implemented and successfully support deep diving operations.

  2. Mirror neuron system based therapy for aphasia rehabilitation

    PubMed Central

    Chen, Wenli; Ye, Qian; Ji, Xiangtong; Zhang, Sicong; Yang, Xi; Zhou, Qiumin; Cong, Fang; Chen, Wei; Zhang, Xin; Zhang, Bing; Xia, Yang; Yuan, Ti-Fei; Shan, Chunlei

    2015-01-01

    Objective: To investigate the effect of hand action observation training, i.e., mirror neuron system (MNS) based training, on language function of aphasic patients after stroke. In addition, to reveal the tentative mechanism underlying this effect. Methods: Six aphasic patients after stroke, meeting the criteria, undergo 3 weeks' training protocol (30 min per day, 6 days per week). Among them, four patients accepted an ABA training design, i.e., they implemented Protocol A (hand action observation combined with repetition) in the first and third weeks and carried out Protocol B (static object observation combined with repetition) in the second week. Conversely, for the other two patients, BAB training design was adopted, i.e., patients took Protocol B in the first and third weeks and accepted Protocol A in the second week. Picture naming test, western aphasia battery (WAB) and Token Test were applied to evaluate the changes of language function before and after each week's training. Furthermore, two subjects (one aphasic patient and one healthy volunteer) attended a functional MRI (fMRI) experiment, by which we tried to reveal the mechanism underlying possible language function changes after training. Results: Compared with static object observation and repetition training (Protocol B), hand action observation and repetition training (Protocol A) effectively improved most aspects of the language function in all six patients, as demonstrated in the picture naming test, subtests of oral language and aphasia quotient (AQ) of WAB. In addition, the fMRI experiment showed that Protocol A induced more activations in the MNS of one patient and one healthy control when compared to Protocol B. Conclusion: The mirror neuron based therapy may facilitate the language recovery for aphasic patients and this, to some extent, provides a novel direction of rehabilitation for aphasia patients. PMID:26579046

  3. Active optics primary mirror support system for the 26m VST telescope

    NASA Astrophysics Data System (ADS)

    Schipani, Pietro; D'Orsi, Sergio; Ferragina, Luigi; Fierro, Davide; Marty, Laurent; Molfese, Cesare; Perrotta, Francesco

    2010-03-01

    The Very Large Telescope Survey Telescope (VST) is equipped with an active optics system in order to correct low-order aberrations. The 2.6 m primary mirror is supported both axially and laterally and is surrounded by several safety devices for earthquake protection. We describe the mirror support system and discuss the results of the qualification test campaign.

  4. Magnetic mirror fusion-fission early history and applicability to other systems

    SciTech Connect

    Moir, R

    2009-08-24

    In the mid 1970s to mid 1980s the mirror program was stuck with a concept, the Standard Mirror that was Q {approx} 1 where Q=P{sub fusion}/P{sub injection}. Heroic efforts were put into hybridizing thinking added energy and fuel sales would make a commercial product. At the same time the tokamak was thought to allow ignition and ultrahigh Q values of 20 or even higher. There was an effort to use neutral beams to drive the tokamak just like the mirror machines were driven in which case the Q value plunged to a few, however this was thought to be achievable decades earlier than the high Q versions. Meanwhile current drive and other features of the tokamak have seen the projected Q values come down to the range of 10. Meanwhile the mirror program got Q enhancement into high gear and various tandem mirrors projected Q values up towards 10 and with advanced features over 10 with axi-symmetric magnets (See R. F. Post papers), however the experimental program is all but non-existent. Meanwhile, the gas dynamic trap mirror system which is present day state-of-the-art can with low risk produce Q of {approx}0.1 useful for a low risk, low cost neutron source for materials development useful for the development of materials for all fusion concepts (see Simonen white paper: 'A Physics-Based Strategy to Develop a Mirror Fusion-Fission Hybrid' and D.D. Ryutov, 'Axisymmetric MHD-stable mirror as a neutron source and a driver for a fusion-fission hybrid'). Many early hybrid designs with multi-disciplinary teams were carried out in great detail for the mirror system with its axi-symmetric blanket modules. It is recognized that most of these designs are adaptable to tokamak or inertial fusion geometry. When Q is low (1 to 2) economics gives a large economic penalty for high recirculating power. These early studies covered the three design types: Power production, fuel production and waste burning. All three had their place but power production fell away because every study showed

  5. Advanced imaging system

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This document describes the Advanced Imaging System CCD based camera. The AIS1 camera system was developed at Photometric Ltd. in Tucson, Arizona as part of a Phase 2 SBIR contract No. NAS5-30171 from the NASA/Goddard Space Flight Center in Greenbelt, Maryland. The camera project was undertaken as a part of the Space Telescope Imaging Spectrograph (STIS) project. This document is intended to serve as a complete manual for the use and maintenance of the camera system. All the different parts of the camera hardware and software are discussed and complete schematics and source code listings are provided.

  6. DESIGN OF MIRRORS AND APODIZATION FUNCTIONS IN PHASE-INDUCED AMPLITUDE APODIZATION SYSTEMS

    SciTech Connect

    Cady, Eric

    2012-08-01

    Phase-induced amplitude apodization (PIAA) coronagraphs are a promising technology for imaging exoplanets, with the potential to detect Earth-like planets around Sun-like stars. A PIAA system nominally consists of a pair of mirrors that reshape incident light without attenuation, coupled with one or more apodizers to mitigate diffraction effects or provide additional beam shaping to produce a desired output profile. We present a set of equations that allow apodizers to be chosen for any given pair of mirrors, or conversely mirror shapes chosen for given apodizers, to produce an arbitrary amplitude profile at the output of the system. We show how classical PIAA systems may be designed by this method and present the design of a novel four-mirror system with higher throughput than a standard two-mirror system. We also discuss the limitations due to diffraction and the design steps that may be taken to mitigate them.

  7. COMPONENTS OF LASER SYSTEMS: Single-channel adaptive mirrors for laser optics

    NASA Astrophysics Data System (ADS)

    Safronov, A. G.

    1995-11-01

    Single-channel deformable mirrors for use in low-correction-order laser adaptive systems were developed and investigated. The structure of the mirrors is described and the results are given of experimental determinations of the initial shape of the optical surface, of the response functions, of the sensitivity, and of the electromechanical hysteresis. Calculations are reported of the thermal deformation of the mirrors subjected to the effects of heat under various conditions, and also of the frequency characteristics of these mirrors. It is shown that such adaptive mirrors are effective in compensation for large-scale axisymmetric distortions of the wavefront in laser optics operating at powers up to 1 kW. The operational range of these mirrors is approximately ±20 μm in respect of the amplitude of the optical surface displacements and up to 1 kHz in respect of the frequency.

  8. TRL-6 Qualification of JWST Mirror Segments

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2009-01-01

    Since 1996, all key mirror technology for a JWST Primary Mirror Segment Assembly (PMSA), as defined directly from the JWST Level 1 Science Requirements, have been developed and matured from a Technology Readiness Level (TRL) of 3 to 6. This has occurred as the result of a highly successful technology development program including sub-scale Beryllium Mirror Demonstrator (SBMD), Advanced Mirror System Demonstrator (AMSD), and JWST flight mirror fabrication. Directly traceable prototypes (and in some cases the flight hardware itself) has been built, tested and operated in a relevant environment.

  9. Advanced Life Support Systems

    NASA Technical Reports Server (NTRS)

    Barta, Daniel J.

    2004-01-01

    This presentation is planned to be a 10-15 minute "catalytic" focused presentation to be scheduled during one of the working sessions at the TIM. This presentation will focus on Advanced Life Support technologies key to future human Space Exploration as outlined in the Vision, and will include basic requirements, assessment of the state-of-the-art and gaps, and include specific technology metrics. The presentation will be technical in character, lean heavily on data in published ALS documents (such as the Baseline Values and Assumptions Document) but not provide specific technical details or build to information on any technology mentioned (thus the presentation will be benign from an export control and a new technology perspective). The topics presented will be focused on the following elements of Advanced Life Support: air revitalization, water recovery, waste management, thermal control, habitation systems, food systems and bioregenerative life support.

  10. LLNL Tandem Mirror Experiment (TMX) upgrade vacuum system

    SciTech Connect

    Pickles, W.L.; Chargin, A.K.; Drake, R.P.

    1981-09-15

    TMX Upgrade is a large, tandem, magnetic-mirror fusion experiment with stringent requirements on base pressure (10/sup -8/ torr), low H reflux from the first walls, and peak gas pressure (5 x 10/sup -7/ torr) due to neutral beam gas during plasma operation. The 225 m/sup 3/ vacuum vessel is initially evacuated by turbopumps. Cryopumps provide a continuous sink for gases other than helium, deuterium, and hydrogen. The neutral beam system introduces up to 480 l/s of H or D. The hydrogen isotopes are pumped at very high speed by titanium sublimed onto two cylindrical radially separated stainless steel quilted liners with a total surface area of 540 m/sup 2/. These surfaces (when cooled to about 80/sup 0/K) provide a pumping speed of 6 x 10/sup 7/ l/s for hydrogen. The titanium getter system is programmable and is used for heating as well as gettering. The inner plasma liner can be operated at elevated temperatures to enhance migration of gases away from the surfaces close to the plasma. Glow discharge cleaning is part of the pumpdown procedure. The design features are discussed in conjunction with the operating procedures developed to manage the dynamic vacuum conditions.

  11. Machine Protection System for the Stepper Motor Actuated SyLMAND Mirrors

    NASA Astrophysics Data System (ADS)

    Subramanian, V. R.; Achenbach, S.; Dolton, W.; Wells, G.; Hallin, E.; Klymyshyn, D. M.; Augustin, M.

    2010-06-01

    SyLMAND, the Synchrotron Laboratory for Micro and Nano Devices at the Canadian Light Source, consists of a dedicated X-ray lithography beamline on a bend magnet port, and process support laboratories in a clean room environment. The beamline includes a double mirror system with flat, chromium-coated silicon mirrors operated at varying grazing angles of incidence (4 mrad to 45 mrad) for spectral adjustment by high energy cut-off. Each mirror can be independently moved by two stepper motors to precisely control the pitch and vertical position. We present in this paper the machine protection system implemented in the double mirror system to allow for safe operation of the two mirrors and to avoid consequences of potential stepper motor malfunction.

  12. Machine Protection System for the Stepper Motor Actuated SyLMAND Mirrors

    SciTech Connect

    Subramanian, V. R.; Dolton, W.; Wells, G.; Hallin, E.; Achenbach, S.; Klymyshyn, D. M.; Augustin, M.

    2010-06-23

    SyLMAND, the Synchrotron Laboratory for Micro and Nano Devices at the Canadian Light Source, consists of a dedicated X-ray lithography beamline on a bend magnet port, and process support laboratories in a clean room environment. The beamline includes a double mirror system with flat, chromium-coated silicon mirrors operated at varying grazing angles of incidence (4 mrad to 45 mrad) for spectral adjustment by high energy cut-off. Each mirror can be independently moved by two stepper motors to precisely control the pitch and vertical position. We present in this paper the machine protection system implemented in the double mirror system to allow for safe operation of the two mirrors and to avoid consequences of potential stepper motor malfunction.

  13. Advanced Clothing System

    NASA Technical Reports Server (NTRS)

    Schlesinger, Thilini; Broyan, James; Orndoff, Evelyne

    2014-01-01

    The goal of the Advanced Clothing System (ACS) is to use advanced commercial off-theshelf fibers and antimicrobial treatments with the goal of directly reducing the mass and volume of a logistics item. The current clothing state-of-the-art on the International Space Station (ISS) is disposable, mostly cotton-based, clothing with no laundry provisions. Each clothing article has varying use periods and will become trash. The goal is to increase the length of wear of the clothing to reduce the logistical mass and volume. The initial focus has been exercise clothing since the use period is lower. Various ground studies and an ISS technology demonstration have been conducted to evaluate clothing preference and length of wear. The analysis indicates that use of ACS selected garments (e.g. wool, modacrylic, polyester) can increase the breakeven point for laundry to 300 days.

  14. Advanced Clothing System

    NASA Technical Reports Server (NTRS)

    Broyan, James; Orndoff, Evelyne

    2014-01-01

    The goal of the Advanced Clothing System (ACS) is to use advanced commercial off-the-shelf fibers and antimicrobial treatments with the goal of directly reducing the mass and volume of a logistics item. The current clothing state-of-the-art on the International Space Station (ISS) is disposable, mostly cotton-based, clothing with no laundry provisions. Each clothing article has varying use periods and will become trash. The goal is to increase the length of wear of the clothing to reduce the logistical mass and volume. The initial focus has been exercise clothing since the use period is lower. Various ground studies and an ISS technology demonstration have been conducted to evaluate clothing preference and length of wear. The analysis indicates that use of ACS selected garments (e.g. wool, modacrylic, polyester) can increase the breakeven point for laundry to 300 days.

  15. Advanced worker protection system

    SciTech Connect

    Caldwell, B.; Duncan, P.; Myers, J.

    1995-12-01

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D&D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D&D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D&D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project will result in the development of an Advanced Worker Protection System (AWPS). The AWPS will be built around a life support backpack that uses liquid air to provide cooling as well as breathing gas to the worker. The backpack will be combined with advanced protective garments, advanced liquid cooling garment, respirator, communications, and support equipment to provide improved worker protection, simplified system maintenance, and dramatically improve worker productivity through longer duration work cycles. Phase I of the project has resulted in a full scale prototype Advanced Worker Protection Ensemble (AWPE, everything the worker will wear), with sub-scale support equipment, suitable for integrated testing and preliminary evaluation. Phase II will culminate in a full scale, certified, pre-production AWPS and a site demonstration.

  16. ADVANCED TURBINE SYSTEMS PROGRAM

    SciTech Connect

    Gregory Gaul

    2004-04-21

    Natural gas combustion turbines are rapidly becoming the primary technology of choice for generating electricity. At least half of the new generating capacity added in the US over the next twenty years will be combustion turbine systems. The Department of Energy has cosponsored with Siemens Westinghouse, a program to maintain the technology lead in gas turbine systems. The very ambitious eight year program was designed to demonstrate a highly efficient and commercially acceptable power plant, with the ability to fire a wide range of fuels. The main goal of the Advanced Turbine Systems (ATS) Program was to develop ultra-high efficiency, environmentally superior and cost effective competitive gas turbine systems for base load application in utility, independent power producer and industrial markets. Performance targets were focused on natural gas as a fuel and included: System efficiency that exceeds 60% (lower heating value basis); Less than 10 ppmv NO{sub x} emissions without the use of post combustion controls; Busbar electricity that are less than 10% of state of the art systems; Reliability-Availability-Maintainability (RAM) equivalent to current systems; Water consumption minimized to levels consistent with cost and efficiency goals; and Commercial systems by the year 2000. In a parallel effort, the program was to focus on adapting the ATS engine to coal-derived or biomass fuels. In Phase 1 of the ATS Program, preliminary investigators on different gas turbine cycles demonstrated that net plant LHV based efficiency greater than 60% was achievable. In Phase 2 the more promising cycles were evaluated in greater detail and the closed-loop steam-cooled combined cycle was selected for development because it offered the best solution with least risk for achieving the ATS Program goals for plant efficiency, emissions, cost of electricity and RAM. Phase 2 also involved conceptual ATS engine and plant design and technology developments in aerodynamics, sealing

  17. Collimating Montel mirror as part of a multi-crystal analyzer system for resonant inelastic X-ray scattering.

    PubMed

    Kim, Jungho; Shi, Xianbo; Casa, Diego; Qian, Jun; Huang, XianRong; Gog, Thomas

    2016-07-01

    Advances in resonant inelastic X-ray scattering (RIXS) have come in lockstep with improvements in energy resolution. Currently, the best energy resolution at the Ir L3-edge stands at ∼25 meV, which is achieved using a diced Si(844) spherical crystal analyzer. However, spherical analyzers are limited by their intrinsic reflection width. A novel analyzer system using multiple flat crystals provides a promising way to overcome this limitation. For the present design, an energy resolution at or below 10 meV was selected. Recognizing that the angular acceptance of flat crystals is severely limited, a collimating element is essential to achieve the necessary solid-angle acceptance. For this purpose, a laterally graded, parabolic, multilayer Montel mirror was designed for use at the Ir L3-absorption edge. It provides an acceptance larger than 10 mrad, collimating the reflected X-ray beam to smaller than 100 µrad, in both vertical and horizontal directions. The performance of this mirror was studied at beamline 27-ID at the Advanced Photon Source. X-rays from a diamond (111) monochromator illuminated a scattering source of diameter 5 µm, generating an incident beam on the mirror with a well determined divergence of 40 mrad. A flat Si(111) crystal after the mirror served as the divergence analyzer. From X-ray measurements, ray-tracing simulations and optical metrology results, it was established that the Montel mirror satisfied the specifications of angular acceptance and collimation quality necessary for a high-resolution RIXS multi-crystal analyzer system. PMID:27359136

  18. Collimating Montel mirror as part of a multi-crystal analyzer system for resonant inelastic X-ray scattering.

    PubMed

    Kim, Jungho; Shi, Xianbo; Casa, Diego; Qian, Jun; Huang, XianRong; Gog, Thomas

    2016-07-01

    Advances in resonant inelastic X-ray scattering (RIXS) have come in lockstep with improvements in energy resolution. Currently, the best energy resolution at the Ir L3-edge stands at ∼25 meV, which is achieved using a diced Si(844) spherical crystal analyzer. However, spherical analyzers are limited by their intrinsic reflection width. A novel analyzer system using multiple flat crystals provides a promising way to overcome this limitation. For the present design, an energy resolution at or below 10 meV was selected. Recognizing that the angular acceptance of flat crystals is severely limited, a collimating element is essential to achieve the necessary solid-angle acceptance. For this purpose, a laterally graded, parabolic, multilayer Montel mirror was designed for use at the Ir L3-absorption edge. It provides an acceptance larger than 10 mrad, collimating the reflected X-ray beam to smaller than 100 µrad, in both vertical and horizontal directions. The performance of this mirror was studied at beamline 27-ID at the Advanced Photon Source. X-rays from a diamond (111) monochromator illuminated a scattering source of diameter 5 µm, generating an incident beam on the mirror with a well determined divergence of 40 mrad. A flat Si(111) crystal after the mirror served as the divergence analyzer. From X-ray measurements, ray-tracing simulations and optical metrology results, it was established that the Montel mirror satisfied the specifications of angular acceptance and collimation quality necessary for a high-resolution RIXS multi-crystal analyzer system.

  19. Morphological differences in the mirror neuron system in Williams Syndrome

    PubMed Central

    Ng, Rowena; Brown, Timothy T.; Erhart, Matthew; Järvinen, Anna M.; Korenberg, Julie R.; Bellugi, Ursula; Halgren, Eric

    2015-01-01

    Williams syndrome (WS) is a genetic condition characterized by an overly gregarious personality, including high empathetic concern for others. Although seemingly disparate from the profile of autism spectrum disorder (ASD), both are associated with deficits in social communication/cognition. Notably, the mirror neuron system (MNS) has been implicated in social dysfunction for ASD; yet, the integrity of this network and its association with social functioning in WS remains unknown. Magnetic resonance imaging methods were used to examine the structural integrity of the MNS of adults with WS versus typically developing (TD) individuals. The Social Responsiveness Scale (SRS), a tool typically used to screen for social features of ASD, was also employed to assess the relationships between social functioning with the MNS morphology in WS participants. WS individuals showed reduced cortical surface area of MNS substrates yet relatively preserved cortical thickness as compared to TD adults. Increased cortical thickness of the inferior parietal lobule was associated with increased deficits in social communication, social awareness, social cognition, and autistic mannerisms. However, social motivation was not related to anatomical features of the MNS. Our findings indicate that social deficits typical to both ASD and WS may be attributed to an aberrant MNS, whereas the unusual social drive marked in WS is subserved by substrates distinct from this network. PMID:26230578

  20. Mirror neuron system and observational learning: behavioral and neurophysiological evidence.

    PubMed

    Lago-Rodriguez, Angel; Lopez-Alonso, Virginia; Fernández-del-Olmo, Miguel

    2013-07-01

    Three experiments were performed to study observational learning using behavioral, perceptual, and neurophysiological data. Experiment 1 investigated whether observing an execution model, during physical practice of a transitive task that only presented one execution strategy, led to performance improvements compared with physical practice alone. Experiment 2 investigated whether performing an observational learning protocol improves subjects' action perception. In experiment 3 we evaluated whether the type of practice performed determined the activation of the Mirror Neuron System during action observation. Results showed that, compared with physical practice, observing an execution model during a task that only showed one execution strategy does not provide behavioral benefits. However, an observational learning protocol allows subjects to predict more precisely the outcome of the learned task. Finally, intersperse observation of an execution model with physical practice results in changes of primary motor cortex activity during the observation of the motor pattern previously practiced, whereas modulations in the connectivity between primary and non primary motor areas (PMv-M1; PPC-M1) were not affected by the practice protocol performed by the observer.

  1. JWST Lightweight Mirror TRL-6 Results

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2007-01-01

    Mirror technology for a Primary Mirror Segment Assembly (PMSA) is a system of components: reflective coating; polished optical surface; mirror substrate; actuators, mechanisms and flexures; and reaction structure. The functional purpose of a PMSA is to survive launch, deploy and align itself to form a 25 square meter collecting area 6.5 meter diameter primary mirror with a 131 nm rms wavefront error at temperatures less than 50K and provide stable optical performance for the anticipated thermal environment. At the inception of JWST in 1996, such a capability was at a Technology Readiness Level (TRL) of 3. A highly successful technology development program was initiated including the Sub-scale Beryllium Mirror Demonstrator (SBMD) and Advanced Mirror System Demonstrator (AMSD) projects. These projects along with flight program activities have matured mirror technology for JWST to TRL-6. A directly traceable prototype (and in some cases the flight hardware itself) has been built, tested and operated in a relevant environment.

  2. Advanced Electrophysiologic Mapping Systems

    PubMed Central

    2006-01-01

    Executive Summary Objective To assess the effectiveness, cost-effectiveness, and demand in Ontario for catheter ablation of complex arrhythmias guided by advanced nonfluoroscopy mapping systems. Particular attention was paid to ablation for atrial fibrillation (AF). Clinical Need Tachycardia Tachycardia refers to a diverse group of arrhythmias characterized by heart rates that are greater than 100 beats per minute. It results from abnormal firing of electrical impulses from heart tissues or abnormal electrical pathways in the heart because of scars. Tachycardia may be asymptomatic, or it may adversely affect quality of life owing to symptoms such as palpitations, headaches, shortness of breath, weakness, dizziness, and syncope. Atrial fibrillation, the most common sustained arrhythmia, affects about 99,000 people in Ontario. It is associated with higher morbidity and mortality because of increased risk of stroke, embolism, and congestive heart failure. In atrial fibrillation, most of the abnormal arrhythmogenic foci are located inside the pulmonary veins, although the atrium may also be responsible for triggering or perpetuating atrial fibrillation. Ventricular tachycardia, often found in patients with ischemic heart disease and a history of myocardial infarction, is often life-threatening; it accounts for about 50% of sudden deaths. Treatment of Tachycardia The first line of treatment for tachycardia is antiarrhythmic drugs; for atrial fibrillation, anticoagulation drugs are also used to prevent stroke. For patients refractory to or unable to tolerate antiarrhythmic drugs, ablation of the arrhythmogenic heart tissues is the only option. Surgical ablation such as the Cox-Maze procedure is more invasive. Catheter ablation, involving the delivery of energy (most commonly radiofrequency) via a percutaneous catheter system guided by X-ray fluoroscopy, has been used in place of surgical ablation for many patients. However, this conventional approach in catheter ablation

  3. Advanced drilling systems study.

    SciTech Connect

    Pierce, Kenneth G.; Livesay, Billy Joe; Finger, John Travis

    1996-05-01

    This report documents the results of a study of advanced drilling concepts conducted jointly for the Natural Gas Technology Branch and the Geothermal Division of the U.S. Department of Energy. A number of alternative rock cutting concepts and drilling systems are examined. The systems cover the range from current technology, through ongoing efforts in drilling research, to highly speculative concepts. Cutting mechanisms that induce stress mechanically, hydraulically, and thermally are included. All functions necessary to drill and case a well are considered. Capital and operating costs are estimated and performance requirements, based on comparisons of the costs for alternative systems to conventional drilling technology, are developed. A number of problems common to several alternatives and to current technology are identified and discussed.

  4. Mirror fusion propulsion system - A performance comparison with alternate propulsion systems for the manned Mars mission

    NASA Technical Reports Server (NTRS)

    Deveny, M.; Carpenter, S.; O'Connell, T.; Schulze, N.

    1993-01-01

    The performance characteristics of several propulsion technologies applied to piloted Mars missions are compared. The characteristics that are compared are Initial Mass in Low Earth Orbit (IMLEO), mission flexibility, and flight times. The propulsion systems being compared are both demonstrated and envisioned: Chemical (or Cryogenic), Nuclear Thermal Rocket (NTR) solid core, NTR gas core, Nuclear Electric Propulsion (NEP), and a mirror fusion space propulsion system. The proposed magnetic mirror fusion reactor, known as the Mirror Fusion Propulsion System (MFPS), is described. The description is an overview of a design study that was conducted to convert a mirror reactor experiment at Lawrence Livermore National Lab (LLNL) into a viable space propulsion system. Design principles geared towards minimizing mass and maximizing power available for thrust are identified and applied to the LLNL reactor design, resulting in the MFPS. The MFPS' design evolution, reactor and fuel choices, and system configuration are described. Results of the performance comparison shows that the MFPS minimizes flight time to 60 to 90 days for flights to Mars while allowing continuous return-home capability while at Mars. Total MFPS IMLEO including propellant and payloads is kept to about 1,000 metric tons.

  5. Mirror fusion propulsion system: A performance comparison with alternate propulsion systems for the manned Mars Mission

    NASA Technical Reports Server (NTRS)

    Schulze, Norman R.; Carpenter, Scott A.; Deveny, Marc E.; Oconnell, T.

    1993-01-01

    The performance characteristics of several propulsion technologies applied to piloted Mars missions are compared. The characteristics that are compared are Initial Mass in Low Earth Orbit (IMLEO), mission flexibility, and flight times. The propulsion systems being compared are both demonstrated and envisioned: Chemical (or Cryogenic), Nuclear Thermal Rocket (NTR) solid core, NTR gas core, Nuclear Electric Propulsion (NEP), and a mirror fusion space propulsion system. The proposed magnetic mirror fusion reactor, known as the Mirror Fusion Propulsion System (MFPS), is described. The description is an overview of a design study that was conducted to convert a mirror reactor experiment at Lawrence Livermore National Lab (LLNL) into a viable space propulsion system. Design principles geared towards minimizing mass and maximizing power available for thrust are identified and applied to the LLNL reactor design, resulting in the MFPS. The MFPS' design evolution, reactor and fuel choices, and system configuration are described. Results of the performance comparison shows that the MFPS minimizes flight time to 60 to 90 days for flights to Mars while allowing continuous return-home capability while at Mars. Total MFPS IMLEO including propellant and payloads is kept to about 1,000 metric tons.

  6. Mirror fusion propulsion system: A performance comparison with alternate propulsion systems for the manned Mars Mission

    SciTech Connect

    Schulze, N.R.; Carpenter, S.A.; Deveny, M.E.; Oconnell, T.

    1993-06-01

    The performance characteristics of several propulsion technologies applied to piloted Mars missions are compared. The characteristics that are compared are Initial Mass in Low Earth Orbit (IMLEO), mission flexibility, and flight times. The propulsion systems being compared are both demonstrated and envisioned: Chemical (or Cryogenic), Nuclear Thermal Rocket (NTR) solid core, NTR gas core, Nuclear Electric Propulsion (NEP), and a mirror fusion space propulsion system. The proposed magnetic mirror fusion reactor, known as the Mirror Fusion Propulsion System (MFPS), is described. The description is an overview of a design study that was conducted to convert a mirror reactor experiment at Lawrence Livermore National Lab (LLNL) into a viable space propulsion system. Design principles geared towards minimizing mass and maximizing power available for thrust are identified and applied to the LLNL reactor design, resulting in the MFPS. The MFPS' design evolution, reactor and fuel choices, and system configuration are described. Results of the performance comparison shows that the MFPS minimizes flight time to 60 to 90 days for flights to Mars while allowing continuous return-home capability while at Mars. Total MFPS IMLEO including propellant and payloads is kept to about 1,000 metric tons.

  7. Method for pulse control in a laser including a stimulated brillouin scattering mirror system

    DOEpatents

    Dane, C. Brent; Hackel, Lloyd; Harris, Fritz B.

    2007-10-23

    A laser system, such as a master oscillator/power amplifier system, comprises a gain medium and a stimulated Brillouin scattering SBS mirror system. The SBS mirror system includes an in situ filtered SBS medium that comprises a compound having a small negative non-linear index of refraction, such as a perfluoro compound. An SBS relay telescope having a telescope focal point includes a baffle at the telescope focal point which blocks off angle beams. A beam splitter is placed between the SBS mirror system and the SBS relay telescope, directing a fraction of the beam to an alternate beam path for an alignment fiducial. The SBS mirror system has a collimated SBS cell and a focused SBS cell. An adjustable attenuator is placed between the collimated SBS cell and the focused SBS cell, by which pulse width of the reflected beam can be adjusted.

  8. Heat Mirror II: an advanced transparent insulation. Phase II. Final report

    SciTech Connect

    Cormia, R.L.

    1982-06-01

    The purpose of this project was to take five separate approaches to achieve an environmentally stable Heat Mirror II. Heat Mirror I is limited to use in hermetically sealed, dessicated environments to avoid risks to its integrity from physical abuse and atmospheric chemical attack. In this report, the following five tasks were addressed, each designed to give Heat Mirror I greater durability: surface preparation of the substrate; alternative thin film stack design; passivation of the thin film stack; overcoating; and laminating. It is concluded that the laminate is very promising and should be further tested.

  9. Northop Grumman/Xinetics Deformable Mirrors: Enabling Reliable Advanced Imaging for 20 Years and Beyond

    NASA Astrophysics Data System (ADS)

    Matijevich, Russ; Jeff Cavaco, Northrop Grumman Xinetics

    2015-01-01

    Adaptive Optics Xinetics (AOX), a wholly-owned subsidiary of Northrop Grumman, has manufactured and delivered more than 300 deformable mirrors (DMs) since 1995. With more than 32 gigacycles of use, these mirrors have significantly increased the scientific return of ground based astronomical telescopes by removing atmospheric distortion from the image plane. AOX deformable mirrors exhibit little or no hysteresis, aging or creep, making them highly reliable and predictable. A range of space -based applications are currently in development or under consideration as key enablers for future astronomical missions. We will review a variety of AOX DMs and discuss a number of their real world applications and results.

  10. Kinematic high bandwidth mirror mount

    DOEpatents

    Kuklo, T.C.

    1995-03-21

    An adjustable mirror mount system for a mirror is disclosed comprising a mirror support having a planar surface thereon, a mirror frame containing a mirror and having a planar surface behind the mirror facing the planar surface of the mirror support and parallel to the reflecting surface of the mirror and mounted pivotally to the mirror support at a point central to the frame, a first adjustment means between the mirror support and the mirror frame spaced from the central pivot mount for adjusting the movement of the mirror along one axis lying in the plane of the planar surface of the mirror frame; and a second adjustment means between the mirror support and the mirror frame spaced from the central pivot mount for adjusting the movement of the mirror along a second axis lying in the plane of the planar surface of the mirror frame and perpendicular to the first axis. 7 figures.

  11. Kinematic high bandwidth mirror mount

    DOEpatents

    Kuklo, Thomas C.

    1995-01-01

    An adjustable mirror mount system for a mirror is disclosed comprising a mirror support having a planar surface thereon, a mirror frame containing a mirror and having a planar surface behind the mirror facing the planar surface of the mirror support and parallel to the reflecting surface of the mirror and mounted pivotally to the mirror support at a point central to the frame, a first adjustment means between the mirror support and the mirror frame spaced from the central pivot mount for adjusting the movement of the mirror along one axis lying in the plane of the planar surface of the mirror frame; and a second adjustment means between the mirror support and the mirror frame spaced from the central pivot mount for adjusting the movement of the mirror along a second axis lying in the plane of the planar surface of the mirror frame and perpendicular to the first axis.

  12. Effect of synchrotron radiation on the advanced fueled field-reversed mirror

    SciTech Connect

    Ho, S.K.

    1980-01-01

    The objective of this study is to investigate the effect of synchrotron radiation on the energy balance or advanced fuels in the field-reversed mirror (FRM) fusion device. The FRM configuration is simulated by the Hill's vortex model. The synchrotron radiant energy loss can be computed by adding the blackbody contribution (0 < omega < omega*) and the transsparent contribution (omega* < omega < infinity), where omega is the radiation frequency and omega* is the cutoff frequency. The cutoff frequency is defined by the frequency at which the plasma's optical depth ..cap alpha..(omega)L is unity, where ..cap alpha.. is the absorption coefficient and L is the plasma dimension. The transparent synchrotron radiation at the higher frequencies is not negligible since it is relatively unaffected by proposed reflectors. Wall reflectivity of 0.9 is assumed. The transport equation is traced along a ray across the plasma using the Runge-Kutta techniques. The power loss is obtained by an angular integral of the result with appropriate geometrical factors. Using the FRM reactor design parameter from C. Baker et al. with electron temperature of 70 keV in the Cat-D burn cycle, the cut-off frequency is located at about nine times the cyclotron fundamental frequency. The transparent portion of the synchrotron radiation is about 0.6 of the blackbody counterpart. The net synchrotron radiation power loss is evaluated to be 0.1 MW whereas the fusion power is found to be 2.3 MW, so the synchrotron radiation power loss only accounts for less than 5% of the total fusion power. Similar results are obtained for the D-He/sup 3/ cycle.

  13. Advanced Containment System

    DOEpatents

    Kostelnik, Kevin M.; Kawamura, Hideki; Richardson, John G.; Noda, Masaru

    2004-10-12

    An advanced containment system for containing buried waste and associated leachate. A trench is dug on either side of the zone of interest containing the buried waste so as to accommodate a micro tunnel boring machine. A series of small diameter tunnels are serially excavated underneath the buried waste. The tunnels are excavated by the micro tunnel boring machine at a consistent depth and are substantially parallel to each other. As tunneling progresses, steel casing sections are connected end to end in the excavated portion of the tunnel so that a steel tube is formed. Each casing section has complementary interlocking structure running its length that interlocks with complementary interlocking structure on the adjacent casing section. Thus, once the first tube is emplaced, placement of subsequent tubes is facilitated by the complementary interlocking structure on the adjacent, previously placed, casing sections.

  14. Advanced Containment System

    DOEpatents

    Kostelnik, Kevin M.; Kawamura, Hideki; Richardson, John G.; Noda, Masaru

    2005-05-24

    An advanced containment system for containing buried waste and associated leachate. A trench is dug on either side of the zone of interest containing the buried waste so as to accommodate a micro tunnel boring machine. A series of small diameter tunnels are serially excavated underneath the buried waste. The tunnels are excavated by the micro tunnel boring machine at a consistent depth and are substantially parallel to each other. As tunneling progresses, steel casing sections are connected end to end in the excavated portion of the tunnel so that a steel tube is formed. Each casing section has complementary interlocking structure running its length that interlocks with complementary interlocking structure on the adjacent casing section. Thus, once the first tube is emplaced, placement of subsequent tubes is facilitated by the complementary interlocking structure on the adjacent, previously placed, casing sections.

  15. Improving the Performance of Three-Mirror Imaging Systems with Freeform Optics

    NASA Technical Reports Server (NTRS)

    Howard, Joseph M.; Wolbach, Steven

    2013-01-01

    The image quality improvement for three-mirror systems by Freeform Optics is surveyed over various f-number and field specifications. Starting with the Korsch solution, we increase the surface shape degrees of freedom and record the improvements.

  16. Freeform mirror for illumination system of color-sequential LCOS pico projector

    NASA Astrophysics Data System (ADS)

    Peng, Wei-Jei; Chen, Chun-Chieh; Huang, Chien-Yao; Hsu, Wei-Yao

    2014-09-01

    An efficient and uniform illumination system with a freeform mirror for a color-sequential LCOS pico projector based on LED is proposed in this paper. The novel homogenizer is composed of a micro lens array and a freeform mirror. A freeform mirror with XY polynomial profile is adopted for the reshaping of light pattern, the correction of keystone distortion and the folding mirror for the reduction of volume. Typically, the design of micro lens array, the aspect ratio of the lenslet is corresponding with that of the panel. However, the crosstalk phenomenon occurs due to each lenslet with different collecting angle in horizontal and vertical direction, especially when the aspect ratio of the panel in our study is 16:9. The crosstalk phenomenon not only reduces efficiency but also generates stray light on the panel. Therefore, we use a micro lens array with square lenslet to eliminate it. Subsequently, the square light pattern on the panel needs to be reshaped to fit the aspect ratio of the panel. A cylindrical mirror with a fixed power is used to compress the light pattern first. However, for the requirement of different focal distances from the cylindrical mirror to the panel on entire surface, it generates severe keystone distortion. A freeform mirror with progressive power variation is employed for the correction of keystone distortion with high overfilled efficiency and the reshaping of the light pattern fitting the ratio of the panel. In the results of optical simulation, JBMA uniformity on the panel is 98 % and the coupling efficiency from LED to the plane of the panel is 85 %. Furthermore, the alignment tolerance of the freeform mirror has also been discussed. Finally, the freeform mirror is fabricated by ultra-precision diamond milling process. The form accuracy and surface roughness of the freeform mirror are less than 0.5 um and 5 nm, respectively.

  17. Design of dual-curvature mirror for linear medium concentration photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Lance, Tamir; Ackler, Harold; Finot, Marc

    2012-01-01

    The impact of mirror shape on energy production in Skyline Solar's reflective trough medium concentration photovoltaic system is reviewed using a combination of commercial and proprietary modeling tools. For linear concentrators, an important parameter for efficiency optimization is the uniformity of the flux line on the photovoltaic cells. A significant source of nonuniformity is the discontinuity of reflected light due to the gap between mirrors along the length of the trough. Standard concentrating solar power trough mirrors have a typical length of 1.5 m with a gap between mirrors of 10 to 20 mm. To reduce nonuniformity of the flux line due to this mirror to mirror gap, Skyline Solar developed a dual curvature mirror that stretches the flux line along the trough axis. Extensive modeling and experiments have been conducted to analyze the impact of this design. The methodology of optimization is presented for the X14 Skyline system architecture, and benefits of up to 3% of energy can be realized at locations with latitude below 30 deg.

  18. Characterising x-ray mirror deformations with a phase measuring deflectometry system

    NASA Astrophysics Data System (ADS)

    Breunig, E.; Friedrich, P.; Proserpio, L.; Winter, A.

    2014-07-01

    MPE is developing modular x-ray mirrors for the next generation of high-energy astronomy missions. The mirror segments are based on thermally formed (a.k.a. slumped) glass sheets, with a typical thickness of 400µm. One of the major challenges is the alignment and integration of the mirror segments and the associated metrology. The optical performance of the mirror can be significantly compromised by adhesive shrinkage, gravity sag or residual stresses influenced by the properties of the mirror mounting and the integration procedure. In parallel with classic coordinate measurement techniques we utilize a deflectometry based metrology system to characterization shape errors of the mirror surfaces. A typical deflectometry setup uses a TFT display to project a sinusoidal pattern onto a specular test surface (SUT) and a camera that observes the reflected image. This reflected image contains slope information of the SUT in the form of distortions of the original displayed pattern. A phase shifting technique can be used to recover this slope information with only very few exposures and reasonable computational effort. The deflectometry system enables us to characterize bonding interfaces of slumped glass mirrors, as well as influence of temporary mounting points, handling and thermal distortions. It is also well suited to measure transient effects.

  19. Advanced hydrologic prediction system

    NASA Astrophysics Data System (ADS)

    Connelly, Brian A.; Braatz, Dean T.; Halquist, John B.; Deweese, Michael M.; Larson, Lee; Ingram, John J.

    1999-08-01

    As our Nation's population and infrastructure grow, natural disasters are becoming a greater threat to our society's stability. In an average year, inland flooding claims 133 lives and resulting property losses exceed 4.0 billion. Last year, 1997, these losses totaled 8.7 billion. Because of this blossoming threat, the National Weather Service (NWS) has requested funding within its 2000 budget to begin national implementation of the Advanced Hydrologic Prediction System (AHPS). With this system in place the NWS will be able to utilize precipitation and climate predictions to provide extended probabilistic river forecasts for risk-based decisions. In addition to flood and drought mitigation benefits, extended river forecasts will benefit water resource managers in decision making regarding water supply, agriculture, navigation, hydropower, and ecosystems. It's estimated that AHPS, if implemented nationwide, would save lives and provide $677 million per year in economic benefits. AHPS is used currently on the Des Moines River basin in Iowa and will be implemented soon on the Minnesota River basin in Minnesota. Experience gained from user interaction is leading to refined and enhanced product formats and displays. This discussion will elaborate on the technical requirements associated with AHPS implementation, its enhanced products and informational displays, and further refinements based on customer feedback.

  20. The anthropomorphic brain: the mirror neuron system responds to human and robotic actions.

    PubMed

    Gazzola, V; Rizzolatti, G; Wicker, B; Keysers, C

    2007-05-01

    In humans and monkeys the mirror neuron system transforms seen actions into our inner representation of these actions. Here we asked if this system responds also if we see an industrial robot perform similar actions. We localised the motor areas involved in the execution of hand actions, presented the same subjects blocks of movies of humans or robots perform a variety of actions. The mirror system was activated strongly by the sight of both human and robotic actions, with no significant differences between these two agents. Finally we observed that seeing a robot perform a single action repeatedly within a block failed to activate the mirror system. This latter finding suggests that previous studies may have failed to find mirror activations to robotic actions because of the repetitiveness of the presented actions. Our findings suggest that the mirror neuron system could contribute to the understanding of a wider range of actions than previously assumed, and that the goal of an action might be more important for mirror activations than the way in which the action is performed.

  1. The design and analysis of 2m telescope's K Mirror system

    NASA Astrophysics Data System (ADS)

    Guo, Peng; Zhang, Jingxu; Yang, Fei; Zhang, Yan

    2014-09-01

    During the alt-azimuth telescope tracking, due to the frame structure of tracking support and relative movement of each mirror in Coude optical path, image plane is rotating. To eliminate the effects of image rotation for imaging and subsequent image processing, dove prism or K mirror are generally used. A set of K mirror system designed for 2m telescope. Affected by various errors in the alignment process, the rotating axis K, the optical axis of the K mirror, and the optical axis of the telescope's optical system can't be fully coincide. This causes the track optical axis drawn on the image is not a point, but a Pascal's limacon. The impact caused by the various sources of error were analyzed in this paper and simulation results have important guiding significance for the alignment error distribution.

  2. Advanced cryo propulsion systems

    NASA Technical Reports Server (NTRS)

    Tabata, William K.

    1991-01-01

    The following topics are presented in viewgraph form: (1) advanced space engine (ASE) chronology; (2) an ASE description; (3) a single expander; (4) a dual expander; (5) split expander; (6) launch vehicle start; (7) space start; (8) chemical transfer propulsion; and (9) an advanced expander test bed.

  3. Advanced worker protection system

    SciTech Connect

    Caldwell, B.; Duncan, P.; Myers, J.

    1995-10-01

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D&D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D&D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D&D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project describes the development of an Advanced Worker Protection System (AWPS) which will include a life-support backpack with liquid air for cooling and as a supply of breathing gas, protective clothing, respirators, communications, and support equipment.

  4. A human mirror neuron system for language: Perspectives from signed languages of the deaf.

    PubMed

    Knapp, Heather Patterson; Corina, David P

    2010-01-01

    Language is proposed to have developed atop the human analog of the macaque mirror neuron system for action perception and production [Arbib M.A. 2005. From monkey-like action recognition to human language: An evolutionary framework for neurolinguistics (with commentaries and author's response). Behavioral and Brain Sciences, 28, 105-167; Arbib M.A. (2008). From grasp to language: Embodied concepts and the challenge of abstraction. Journal de Physiologie Paris 102, 4-20]. Signed languages of the deaf are fully-expressive, natural human languages that are perceived visually and produced manually. We suggest that if a unitary mirror neuron system mediates the observation and production of both language and non-linguistic action, three prediction can be made: (1) damage to the human mirror neuron system should non-selectively disrupt both sign language and non-linguistic action processing; (2) within the domain of sign language, a given mirror neuron locus should mediate both perception and production; and (3) the action-based tuning curves of individual mirror neurons should support the highly circumscribed set of motions that form the "vocabulary of action" for signed languages. In this review we evaluate data from the sign language and mirror neuron literatures and find that these predictions are only partially upheld. PMID:19576628

  5. A human mirror neuron system for language: Perspectives from signed languages of the deaf.

    PubMed

    Knapp, Heather Patterson; Corina, David P

    2010-01-01

    Language is proposed to have developed atop the human analog of the macaque mirror neuron system for action perception and production [Arbib M.A. 2005. From monkey-like action recognition to human language: An evolutionary framework for neurolinguistics (with commentaries and author's response). Behavioral and Brain Sciences, 28, 105-167; Arbib M.A. (2008). From grasp to language: Embodied concepts and the challenge of abstraction. Journal de Physiologie Paris 102, 4-20]. Signed languages of the deaf are fully-expressive, natural human languages that are perceived visually and produced manually. We suggest that if a unitary mirror neuron system mediates the observation and production of both language and non-linguistic action, three prediction can be made: (1) damage to the human mirror neuron system should non-selectively disrupt both sign language and non-linguistic action processing; (2) within the domain of sign language, a given mirror neuron locus should mediate both perception and production; and (3) the action-based tuning curves of individual mirror neurons should support the highly circumscribed set of motions that form the "vocabulary of action" for signed languages. In this review we evaluate data from the sign language and mirror neuron literatures and find that these predictions are only partially upheld.

  6. ADVANCED WORKER PROTECTION SYSTEM

    SciTech Connect

    Judson Hedgehock

    2001-03-16

    From 1993 to 2000, OSS worked under a cost share contract from the Department of Energy (DOE) to develop an Advanced Worker Protection System (AWPS). The AWPS is a protective ensemble that provides the user with both breathing air and cooling for a NIOSH-rated duration of two hours. The ensemble consists of a liquid air based backpack, a Liquid Cooling Garment (LCG), and an outer protective garment. The AWPS project was divided into two phases. During Phase 1, OSS developed and tested a full-scale prototype AWPS. The testing showed that workers using the AWPS could work twice as long as workers using a standard SCBA. The testing also provided performance data on the AWPS in different environments that was used during Phase 2 to optimize the design. During Phase 1, OSS also performed a life-cycle cost analysis on a representative clean up effort. The analysis indicated that the AWPS could save the DOE millions of dollars on D and D activities and improve the health and safety of their workers. During Phase 2, OSS worked to optimize the AWPS design to increase system reliability, to improve system performance and comfort, and to reduce the backpack weight and manufacturing costs. To support this design effort, OSS developed and tested several different generations of prototype units. Two separate successful evaluations of the ensemble were performed by the International Union of Operation Engineers (IUOE). The results of these evaluations were used to drive the design. During Phase 2, OSS also pursued certifying the AWPS with the applicable government agencies. The initial intent during Phase 2 was to finalize the design and then to certify the system. OSS and Scott Health and Safety Products teamed to optimize the AWPS design and then certify the system with the National Institute of Occupational Health and Safety (NIOSH). Unfortunately, technical and programmatic difficulties prevented us from obtaining NIOSH certification. Despite the inability of NIOSH to certify

  7. The mirror neuron system and the strange case of Broca's area.

    PubMed

    Cerri, Gabriella; Cabinio, Monia; Blasi, Valeria; Borroni, Paola; Iadanza, Antonella; Fava, Enrica; Fornia, Luca; Ferpozzi, Valentina; Riva, Marco; Casarotti, Alessandra; Martinelli Boneschi, Filippo; Falini, Andrea; Bello, Lorenzo

    2015-03-01

    Mirror neurons, originally described in the monkey premotor area F5, are embedded in a frontoparietal network for action execution and observation. A similar Mirror Neuron System (MNS) exists in humans, including precentral gyrus, inferior parietal lobule, and superior temporal sulcus. Controversial is the inclusion of Broca's area, as homologous to F5, a relevant issue in light of the mirror hypothesis of language evolution, which postulates a key role of Broca's area in action/speech perception/production. We assess "mirror" properties of this area by combining neuroimaging and intraoperative neurophysiological techniques. Our results show that Broca's area is minimally involved in action observation and has no motor output on hand or phonoarticulatory muscles, challenging its inclusion in the MNS. The presence of these functions in premotor BA6 makes this area the likely homologue of F5 suggesting that the MNS may be involved in the representation of articulatory rather than semantic components of speech.

  8. Advanced Integrated Traction System

    SciTech Connect

    Greg Smith; Charles Gough

    2011-08-31

    The United States Department of Energy elaborates the compelling need for a commercialized competitively priced electric traction drive system to proliferate the acceptance of HEVs, PHEVs, and FCVs in the market. The desired end result is a technically and commercially verified integrated ETS (Electric Traction System) product design that can be manufactured and distributed through a broad network of competitive suppliers to all auto manufacturers. The objectives of this FCVT program are to develop advanced technologies for an integrated ETS capable of 55kW peak power for 18 seconds and 30kW of continuous power. Additionally, to accommodate a variety of automotive platforms the ETS design should be scalable to 120kW peak power for 18 seconds and 65kW of continuous power. The ETS (exclusive of the DC/DC Converter) is to cost no more than $660 (55kW at $12/kW) to produce in quantities of 100,000 units per year, should have a total weight less than 46kg, and have a volume less than 16 liters. The cost target for the optional Bi-Directional DC/DC Converter is $375. The goal is to achieve these targets with the use of engine coolant at a nominal temperature of 105C. The system efficiency should exceed 90% at 20% of rated torque over 10% to 100% of maximum speed. The nominal operating system voltage is to be 325V, with consideration for higher voltages. This project investigated a wide range of technologies, including ETS topologies, components, and interconnects. Each technology and its validity for automotive use were verified and then these technologies were integrated into a high temperature ETS design that would support a wide variety of applications (fuel cell, hybrids, electrics, and plug-ins). This ETS met all the DOE 2010 objectives of cost, weight, volume and efficiency, and the specific power and power density 2015 objectives. Additionally a bi-directional converter was developed that provides charging and electric power take-off which is the first step

  9. ADVANCED TURBINE SYSTEMS PROGRAM

    SciTech Connect

    Sy Ali

    2002-03-01

    The market for power generation equipment is undergoing a tremendous transformation. The traditional electric utility industry is restructuring, promising new opportunities and challenges for all facilities to meet their demands for electric and thermal energy. Now more than ever, facilities have a host of options to choose from, including new distributed generation (DG) technologies that are entering the market as well as existing DG options that are improving in cost and performance. The market is beginning to recognize that some of these users have needs beyond traditional grid-based power. Together, these changes are motivating commercial and industrial facilities to re-evaluate their current mix of energy services. One of the emerging generating options is a new breed of advanced fuel cells. While there are a variety of fuel cell technologies being developed, the solid oxide fuel cells (SOFC) and molten carbonate fuel cells (MCFC) are especially promising, with their electric efficiency expected around 50-60 percent and their ability to generate either hot water or high quality steam. In addition, they both have the attractive characteristics of all fuel cells--relatively small siting footprint, rapid response to changing loads, very low emissions, quiet operation, and an inherently modular design lending itself to capacity expansion at predictable unit cost with reasonably short lead times. The objectives of this project are to:(1) Estimate the market potential for high efficiency fuel cell hybrids in the U.S.;(2) Segment market size by commercial, industrial, and other key markets;(3) Identify and evaluate potential early adopters; and(4) Develop results that will help prioritize and target future R&D investments. The study focuses on high efficiency MCFC- and SOFC-based hybrids and competing systems such as gas turbines, reciprocating engines, fuel cells and traditional grid service. Specific regions in the country have been identified where these

  10. Noncontact full-angle fluorescence molecular tomography system based on rotary mirrors.

    PubMed

    Wang, Daifa; He, Jin; Qiao, Huiting; Li, Ping; Fan, Yubo; Li, Deyu

    2015-08-10

    We propose a novel noncontact fluorescence molecular tomography system that achieves full-angle capacity with the use of a new rotary-mirrors-based imaging head. In the imaging head, four plane mirrors are mounted on a rotating gantry to enable illumination and detection over 360°. In comparison with existing full-angle systems, our system does not require rotation of the specimen animal, a large and heavy light source (with scanning head), or a bulky camera (with filters and lens). The system design and implementation are described in detail. Both physical phantom and in vivo experiments are performed to verify the performance of the proposed system.

  11. Does dysfunction of the mirror neuron system contribute to symptoms in amyotrophic lateral sclerosis?

    PubMed

    Eisen, Andrew; Lemon, Roger; Kiernan, Matthew C; Hornberger, Michael; Turner, Martin R

    2015-07-01

    There is growing evidence that mirror neurons, initially discovered over two decades ago in the monkey, are present in the human brain. In the monkey, mirror neurons characteristically fire not only when it is performing an action, such as grasping an object, but also when observing a similar action performed by another agent (human or monkey). In this review we discuss the origin, cortical distribution and possible functions of mirror neurons as a background to exploring their potential relevance in amyotrophic lateral sclerosis (ALS). We have recently proposed that ALS (and the related condition of frontotemporal dementia) may be viewed as a failure of interlinked functional complexes having their origins in key evolutionary adaptations. This can include loss of the direct projections from the corticospinal tract, and this is at least part of the explanation for impaired motor control in ALS. Since, in the monkey, corticospinal neurons also show mirror properties, ALS in humans might also affect the mirror neuron system. We speculate that a defective mirror neuron system might contribute to other ALS deficits affecting motor imagery, gesture, language and empathy.

  12. Does dysfunction of the mirror neuron system contribute to symptoms in amyotrophic lateral sclerosis?

    PubMed

    Eisen, Andrew; Lemon, Roger; Kiernan, Matthew C; Hornberger, Michael; Turner, Martin R

    2015-07-01

    There is growing evidence that mirror neurons, initially discovered over two decades ago in the monkey, are present in the human brain. In the monkey, mirror neurons characteristically fire not only when it is performing an action, such as grasping an object, but also when observing a similar action performed by another agent (human or monkey). In this review we discuss the origin, cortical distribution and possible functions of mirror neurons as a background to exploring their potential relevance in amyotrophic lateral sclerosis (ALS). We have recently proposed that ALS (and the related condition of frontotemporal dementia) may be viewed as a failure of interlinked functional complexes having their origins in key evolutionary adaptations. This can include loss of the direct projections from the corticospinal tract, and this is at least part of the explanation for impaired motor control in ALS. Since, in the monkey, corticospinal neurons also show mirror properties, ALS in humans might also affect the mirror neuron system. We speculate that a defective mirror neuron system might contribute to other ALS deficits affecting motor imagery, gesture, language and empathy. PMID:25727900

  13. Design and experimental results for a compact laser printer optical system with MEMS scanning mirror

    NASA Astrophysics Data System (ADS)

    Suzuki, Takatoshi; Seki, Daisuke; Fujii, Shuichi; Mukai, Yukihiro

    2010-02-01

    There are many features expected by printer users, which include high resolution, low price, compact size, color, high speed printing and so on. Laser printers generally utilize a polygon mirror as a reflector in their optical configurations, but the usual size of the polygon mirror prevents laser scanning unit from being made much smaller. We have been conducting research on techniques which can contribute to reducing the optical unit size. Although oscillating mirror made with MEMS technology enables the system to be compact, it requires a sophisticated optical design having an increased number of constraints due to the change in angular velocity which varies depending on the orientation of the mirror, while the polygon mirror allows the scanning with constant speed. Using a small MEMS mirror is one of the critical issues concerning the reduction of cost. We have successfully resolved all the challenges listed above by using high-precision free-form optical surfaces and an optical layout making efficient use of 3D space. Our techniques can make the unit size much smaller and reduce the price. The optical path is designed to have a ray passing through a lens twice. We report both theoretical and experimental results for this system.

  14. Self-Processing and the Default Mode Network: Interactions with the Mirror Neuron System

    PubMed Central

    Molnar-Szakacs, Istvan; Uddin, Lucina Q.

    2013-01-01

    Recent evidence for the fractionation of the default mode network (DMN) into functionally distinguishable subdivisions with unique patterns of connectivity calls for a reconceptualization of the relationship between this network and self-referential processing. Advances in resting-state functional connectivity analyses are beginning to reveal increasingly complex patterns of organization within the key nodes of the DMN – medial prefrontal cortex and posterior cingulate cortex – as well as between these nodes and other brain systems. Here we review recent examinations of the relationships between the DMN and various aspects of self-relevant and social-cognitive processing in light of emerging evidence for heterogeneity within this network. Drawing from a rapidly evolving social-cognitive neuroscience literature, we propose that embodied simulation and mentalizing are processes which allow us to gain insight into another’s physical and mental state by providing privileged access to our own physical and mental states. Embodiment implies that the same neural systems are engaged for self- and other-understanding through a simulation mechanism, while mentalizing refers to the use of high-level conceptual information to make inferences about the mental states of self and others. These mechanisms work together to provide a coherent representation of the self and by extension, of others. Nodes of the DMN selectively interact with brain systems for embodiment and mentalizing, including the mirror neuron system, to produce appropriate mappings in the service of social-cognitive demands. PMID:24062671

  15. Advanced Microturbine Systems

    SciTech Connect

    Rosfjord, T; Tredway, W; Chen, A; Mulugeta, J; Bhatia, T

    2008-12-31

    In July 2000, the United Technologies Research Center (UTRC) was one of five recipients of a US Department of Energy contract under the Advanced Microturbine System (AMS) program managed by the Office of Distributed Energy (DE). The AMS program resulted from several government-industry workshops that recognized that microturbine systems could play an important role in improving customer choice and value for electrical power. That is, the group believed that electrical power could be delivered to customers more efficiently and reliably than the grid if an effective distributed energy strategy was followed. Further, the production of this distributed power would be accomplished with less undesirable pollutants of nitric oxides (NOx) unburned hydrocarbons (UHC), and carbon monoxide (CO). In 2000, the electrical grid delivered energy to US customers at a national average of approximately 32% efficiency. This value reflects a wide range of powerplants, but is dominated by older, coal burning stations that provide approximately 50% of US electrical power. The grid efficiency is also affected by transmission and distribution (T&D) line losses that can be significant during peak power usage. In some locations this loss is estimated to be 15%. Load pockets can also be so constrained that sufficient power cannot be transmitted without requiring the installation of new wires. New T&D can be very expensive and challenging as it is often required in populated regions that do not want above ground wires. While historically grid reliability has satisfied most customers, increasing electronic transactions and the computer-controlled processes of the 'digital economy' demand higher reliability. For them, power outages can be very costly because of transaction, work-in-progress, or perishable commodity losses. Powerplants that produce the grid electrical power emit significant levels of undesirable NOx, UHC, and CO pollutants. The level of emission is quoted as either a technology

  16. Improving vision-based motor rehabilitation interactive systems for users with disabilities using mirror feedback.

    PubMed

    Jaume-i-Capó, Antoni; Martínez-Bueso, Pau; Moyà-Alcover, Biel; Varona, Javier

    2014-01-01

    Observation is recommended in motor rehabilitation. For this reason, the aim of this study was to experimentally test the feasibility and benefit of including mirror feedback in vision-based rehabilitation systems: we projected the user on the screen. We conducted a user study by using a previously evaluated system that improved the balance and postural control of adults with cerebral palsy. We used a within-subjects design with the two defined feedback conditions (mirror and no-mirror) with two different groups of users (8 with disabilities and 32 without disabilities) using usability measures (time-to-start (T(s)) and time-to-complete (T(c))). A two-tailed paired samples t-test confirmed that in case of disabilities the mirror feedback facilitated the interaction in vision-based systems for rehabilitation. The measured times were significantly worse in the absence of the user's own visual feedback (T(s) = 7.09 (P < 0.001) and T(c) = 4.48 (P < 0.005)). In vision-based interaction systems, the input device is the user's own body; therefore, it makes sense that feedback should be related to the body of the user. In case of disabilities the mirror feedback mechanisms facilitated the interaction in vision-based systems for rehabilitation. Results recommends developers and researchers use this improvement in vision-based motor rehabilitation interactive systems.

  17. Improving Vision-Based Motor Rehabilitation Interactive Systems for Users with Disabilities Using Mirror Feedback

    PubMed Central

    Martínez-Bueso, Pau; Moyà-Alcover, Biel

    2014-01-01

    Observation is recommended in motor rehabilitation. For this reason, the aim of this study was to experimentally test the feasibility and benefit of including mirror feedback in vision-based rehabilitation systems: we projected the user on the screen. We conducted a user study by using a previously evaluated system that improved the balance and postural control of adults with cerebral palsy. We used a within-subjects design with the two defined feedback conditions (mirror and no-mirror) with two different groups of users (8 with disabilities and 32 without disabilities) using usability measures (time-to-start (Ts) and time-to-complete (Tc)). A two-tailed paired samples t-test confirmed that in case of disabilities the mirror feedback facilitated the interaction in vision-based systems for rehabilitation. The measured times were significantly worse in the absence of the user's own visual feedback (Ts = 7.09 (P < 0.001) and Tc = 4.48 (P < 0.005)). In vision-based interaction systems, the input device is the user's own body; therefore, it makes sense that feedback should be related to the body of the user. In case of disabilities the mirror feedback mechanisms facilitated the interaction in vision-based systems for rehabilitation. Results recommends developers and researchers use this improvement in vision-based motor rehabilitation interactive systems. PMID:25295310

  18. Suppression of the first flute mode in a long axisymmetric mirror system

    SciTech Connect

    Arsenin, V.V.

    1982-05-01

    The lowest mode of the flute instability of a plasma with ..beta..<<1 in a confinement system with a simple mirror field: the displacement of the plasma as a whole: can be suppressed if the confinement system is connected with another plasma-filled, axisymmetric, annular confinement system, so that there is a sharp maximum in B beyond the outer boundary of the bell-shaped plasma in the annular system. If the simple mirror is so long that all the other flute modes are stabilized by the finite-Larmor-radius effect, the plasma proves stable with respect to flute perturbations.

  19. Advanced border monitoring sensor system

    NASA Astrophysics Data System (ADS)

    Knobler, Ronald A.; Winston, Mark A.

    2008-04-01

    McQ has developed an advanced sensor system tailored for border monitoring that has been delivered as part of the SBInet program for the Department of Homeland Security (DHS). Technology developments that enhance a broad range of features are presented in this paper, which address the overall goal of the system to improving unattended ground sensor system capabilities for border monitoring applications. Specifically, this paper addresses a system definition, communications architecture, advanced signal processing to classify targets, and distributed sensor fusion processing.

  20. No evidence for mirror system dysfunction in schizophrenia from a multimodal TMS/EEG study.

    PubMed

    Andrews, Sophie C; Enticott, Peter G; Hoy, Kate E; Thomson, Richard H; Fitzgerald, Paul B

    2015-08-30

    Dysfunctional mirror neuron systems have been proposed to contribute to the social cognitive deficits observed in schizophrenia. A few studies have explored mirror systems in schizophrenia using various techniques such as TMS (levels of motor resonance) or EEG (levels of mu suppression), with mixed results. This study aimed to use a novel multimodal approach (i.e. concurrent TMS and EEG) to further investigate mirror systems and social cognition in schizophrenia. Nineteen individuals with schizophrenia or schizoaffective disorder and 19 healthy controls participated. Single-pulse TMS was applied to M1 during the observation of hand movements designed to elicit mirror system activity. Single EEG electrodes (C3, CZ, C4) recorded brain activity. Participants also completed facial affect recognition and theory of mind tasks. The schizophrenia group showed significant deficits in facial affect recognition and higher level theory of mind compared to healthy controls. A significant positive relationship was revealed between mu suppression and motor resonance for the overall sample, indicating concurrent validity of these measures. Levels of mu suppression and motor resonance were not significantly different between groups. These findings indicate that in stable outpatients with schizophrenia, mirror system functioning is intact, and therefore their social cognitive difficulties may be caused by alternative pathophysiology.

  1. Profile Coating for KB Mirror Applications at the Advanced Photon Source

    NASA Astrophysics Data System (ADS)

    Liu, C.; Assoufid, L.; Macrander, A.; Ice, G.; Tischler, J.

    2002-01-01

    For microfocusing x-ray mirrors, an ellipse shape is desirable for aberration-free optics. However, it is difficult to polish elliptical mirrors to x-ray quality smoothness. A differential coating method to convert a cylindrical mirror to an elliptical one has been previously reported The differential coating was obtained by varying the sputter source power while the mirror was passed through. Here we report a new method of profile coating to achieve the same goal more effectively. In the profile coating, the sputter source power is kept constant, while the substrate is passed over a contoured mask at a constant speed. The mask is placed very close to the substrate level (within 1.0 mm) on a shield-can over the sputter gun. Four-inch-diameter Si wafers were coated through a 100-mm-long by 152-mm-wide aperture on the top of the shield-can. The thickness distribution was then obtained using a spectroscopic ellipsometer with computer-controlled X-Y translation stages. A model has been developed to fit the measured thickness distribution of stationary growth. The relative thickness weightings are then digitized at every point 1 mm apart for the entire open area of the aperture. When the substrate is moving across the shield-can during a deposition, the film thickness is directly proportional to the length of the opening on the can along the moving direction. By equating the summation of relative weighting to the required relative thickness at the same position, the length of the opening at that position can be determined. By repeating the same process for the whole length of the required profile, a contour can be obtained for a desired thickness profile. The contoured mask is then placed on the opening of the shield-can. The number of passes and the moving speed of the substrate are determined according to the required thickness and the growth-rate calibration. The mirror coating profile is determined from the ideal surface figure of a focus ellipse and that obtained

  2. Design of the Apache-Point Observatory 3.5-METER Telescope - Part Three - Primary Mirror Support System

    NASA Astrophysics Data System (ADS)

    Mannery, E. J.; Siegmund, W. A.; Hull, M. T.

    1986-01-01

    The authors describe a system of pneumatic piston mirror supports for use in an altitude over azimuth telescope which react to gravity and wind loading. A pressure controller provides dynamic compensation of variable wind loading and changes in the gravity loading as a result of altitude angle changes. An active air circulation system which ventilates every honeycomb cell can be implemented without interference from the mirror supports. The system can be expanded in principle to accomodate 8 m honeycomb mirrors.

  3. Unload control of double fast steering mirrors of the control system

    NASA Astrophysics Data System (ADS)

    Tang, T.; Tan, Y.; Ren, G.

    2015-02-01

    Double fast steering mirror (FSM) are made of a fast steering mirror driven by piezoelectric actuator and a fast steering mirror by voice coin motor, which provides not only high control bandwidth and high resolution but also a wide range of angle for the tracking control system. A classical control system of double fast steering mirror is that each CCD sensor provides line of sight error to control relevant FSM respectively, resulting in complexity and weakening optical energy. The proposed system works by depending on single CCD sensor, which implies that it is crucial to decouple the control double fast steering mirror .An unload technique is designed to solve this problem .The FSM driven by piezoelectric actuator is driven using line of sight from CCD, while the other FSM is followed it. Error attenuation transfer function is modeled and used to analyze stabilization and performance of the control system, which is optimal only if the control bandwidth of FSM driven by piezoelectric actuator is ten times more than that of the FSM driven by the voice coin motor. The experimental results are in great accordance with theoretical analysis.

  4. Improvements to the Apache Point 3.5-m primary-mirror support system

    NASA Astrophysics Data System (ADS)

    Brown, Yorke J.; Davis, Jon E.

    1998-05-01

    The primary mirror of the Apache Point 3.5 meter telescope rests on an array of small pneumatic actuators distributed over the back plate of the mirror and within its honey comb cells. A control system constantly adjusts the pressure in the actuators so as to synthesize a perfectly rigid mounting, thus maintaining both the figure of the mirror and its orientation with respect to the mirror cell. In its original configuration, the APO 3.5 meter system exhibited a number of anomalous behaviors that detracted from the optical performance of the telescope. Analysis of the design indicated three basic problems: first that the pneumatic servovalves suffered from mechanical nonlinearities and an adverse dependence of their transfer function on operating pressure; second, that the air supply system could not exhaust air from the actuators rapidly enough near the horizon and zenith; and third, that the control system did not adequately account for the inertia of the mirror under dynamic conditions. Consequently, we have designed and installed a new control system which addresses these deficiencies. The new system employs high-bandwidth, flapper-type proportional valves that eliminate the mechanical problems and permit implementation of a high- performance controller. The new controller utilizes the existing hard points for mirror position sensing, but implements a pressure-feedback inner loop and a more sophisticated dynamic model. The air supply system now incorporates a sub-atmospheric return and operates closed- loop to minimize contamination problems. The new system exhibits substantial improvements over its previous performance, with positioning errors in the sub-micron range. The design has been selected for use on the Sloan Digital Sky Survey telescope.

  5. Analysis of a scanning pentaprism system for measurements of large flat mirrors.

    PubMed

    Yellowhair, Julius; Burge, James H

    2007-12-10

    The optical surface of a large optical flat can be measured using an autocollimator and scanning pentaprism system. The autocollimator measures the slope difference between a point on the mirror and a reference point. Such a system was built and previously operated at the University of Arizona. We discuss refinements that were made to the hardware, the alignment procedure, and the error analysis. The improved system was demonstrated with a 1.6 m flat mirror, which was measured to be flat to 12 nm rms. The uncertainty in the measurement is only 9 nm rms.

  6. Analysis of a scanning pentaprism system for measurements of large flat mirrors

    SciTech Connect

    Yellowhair, Julius; Burge, James H

    2007-12-10

    The optical surface of a large optical flat can be measured using an autocollimator and scanning pentaprism system. The autocollimator measures the slope difference between a point on the mirror and a reference point. Such a system was built and previously operated at the University of Arizona. We discuss refinements that were made to the hardware, the alignment procedure, and the error analysis.The improved system was demonstrated with a 1.6 m flat mirror, which was measured to be flat to 12 nm rms. The uncertainty in the measurement is only 9 nm rms.

  7. Design of an elliptically bent refocus mirror for the MERLIN beamline at the advanced light source

    NASA Astrophysics Data System (ADS)

    Kelez, Nicholas; Chuang, Yi-De; Smith-Baumann, Alexis; Franck, Keith; Duarte, R.; Lanzara, A.; Hasan, M. Z.; Dessau, D. S.; Chiang, T. C.; Shen, Z.-X.; Hussain, Zahid

    2007-11-01

    There is an increasing demand for well-focused beam with high quality imaging of the full field to further explore the potential of novel instruments. For beamlines operating at focal point, mechanical benders have often been used to shape the refocusing mirror into an ideal elliptical cylinder. Unfortunately, the limited number of couplings for these mechanisms requires specific substrate side-shaping, often calculated using beam bending theory [J.H. Underwood, Space Sci. Instrum. 3 (1977) 259; M. Howells et al., Opt. Eng. 39 (2000) 2748; T. Warwick et al., Document available at OSTI website: http://www.osti.gov/energycitations/servlets/purl/842557-JYZCS3/native/], to meet demanding figure requirements. Here, we use finite element analysis (FEA) to validate the side-shaping algorithm and then couple the output with SHADOW to evaluate mirror performance when an ideal ellipse is not achieved.

  8. Advanced ultraviolet-resistant silver mirrors for use in solar reflectors

    DOEpatents

    Jorgensen, Gary J.; Gee, Randy

    2009-11-03

    A silver mirror construction that maintains a high percentage of hemispherical reflectance throughout the UV and visible spectrum when used in solar reflectors, comprising:a) a pressure sensitive adhesive layer positioned beneath a silver overlay;b) a polymer film disposed on the silver overlay;c) an adhesive layer positioned on the polymer film; andd) a UV screening acrylic film disposed on the adhesive layer.

  9. Control System Modeling for the Thirty Meter Telescope Primary Mirror

    NASA Technical Reports Server (NTRS)

    MacMynowski, Douglas G.; Thompson, Peter M.; Shelton, J. Chris; Roberts, Lewis C., Jr.; Colavita, M. Mark; Sirota, Mark J.

    2011-01-01

    The Thirty Meter Telescope primary mirror is composed of 492 segments that are controlled to high precision in the presence of wind and vibration disturbances, despite the interaction with structural dynamics. The higher bandwidth and larger number of segments compared with the Keck telescopes requires greater attention to modeling to ensure success. We focus here on the development and validation of a suite of quasi-static and dynamic modeling tools required to support the design process, including robustness verification, performance estimation, and requirements flowdown. Models are used to predict the dynamic response due to wind and vibration disturbances, estimate achievable bandwidth in the presence of control-structure-interaction (CSI) and uncertainty in the interaction matrix, and simulate and analyze control algorithms and strategies, e.g. for control of focus-mode, and sensor calibration. Representative results illustrate TMT performance scaling with parameters, but the emphasis is on the modeling framework itself.

  10. Modeling of microelectromechanical systems deformable mirror diffraction grating

    NASA Astrophysics Data System (ADS)

    Sirbu, Dan; Pluzhnik, Eugene; Belikov, Ruslan

    2016-07-01

    Model-based wavefront control methods such as electric field conjugation require accurate optical propagation models to create high-contrast regions in the focal plane using deformable mirrors (DMs). Recently, it has been shown that it is possible to exceed the controllable outer-working angle imposed by the Nyquist limit based on the number of actuators by utilizing a diffraction grating. The print-through pattern on MEMS-based DMs formed during the fabrication process creates both an amplitude and a phase diffraction grating that can be used to enable Super-Nyquist wavefront control. Using interferometric measurements of a DM-actuator, we develop a DM-diffraction grating model. We compare the total energy enclosed in the first diffraction order due to the phase, amplitude, and combined phase-amplitude gratings with laboratory measurements.

  11. Control and network system of force actuators for deformable mirror active optics in LAMOST

    NASA Astrophysics Data System (ADS)

    Zhang, Shengtao; Zhang, Zhenchao; Wang, You

    2007-12-01

    The reflecting Schmidt plate M A of LAMOST consists of 24 segmented hexagonal sub-mirrors. Each sub-mirror is 25mm thick and 1.1m in diagonal. There are 34 force actuators on the back of one sub-mirror which need to be controlled to offer precise load to create correct mirror deformation. This paper presents the control method and network configuration of force actuators for one sub-mirror. Master computer running Windows NT operation system and slave controllers running DOS operation system are connected together via Ethernet local area network (ELAN) by means of TCP/IP protocol. Adopting five slave controllers, 34 force actuators are combined into a distributed system. Master computer controls five slave controllers and five slave controllers operate 34 force actuators. Master computer communicates with slave controllers normally, which receives state of each force actuator from slave controllers and sends instructions to slave controllers via Ethernet LAN. Each slave controller operates 8 force actuators to offer correct load. Axial load capacity of force actuator is +/-150N (pull and push) with accuracy RMS <=0.05N. Force sensor is used as close-loop feedback apparatus to detect the micro load of the actuator.

  12. Profile coating for KB mirror applications at the Advanced Photon Source

    NASA Astrophysics Data System (ADS)

    Liu, Chian; Assoufid, L.; Macrander, Albert T.; Ice, Gene E.; Tischler, J. Z.

    2002-12-01

    For microfocusing x-ray mirrors, an ellipse shape is desirable for aberration-free optics. However, it is difficult to polish elliptical mirrors to x-ray quality smoothness. A differential coating method to convert a cylindrical mirror to an elliptical one has been previously reported The differential coating was obtained by varying the sputter source power while the mirror was passed through. Here we report a new method of profile coating to achieve the same goal more effectively. In the profile coating, the sputter source power is kept constant, while the substrate is passed over a contoured mask at a constant speed. The mask is placed very close to the substrate level (within 1.0 mm) on a shield-can over the sputter gun. Four-inch-diameter Si wafers were coated through a 100-mm-long by 152-mm-wide aperture on the top of the shield-can. The thickness distribution was then obtained using a spectroscopic ellipsometer with computer-controlled X-Y translation stages. A model has been developed to fit the measured thickness distribution of stationary growth. The relative thickness weightings are then digitized at every point 1 mm apart for the entire open area of the aperture. When the substrate is moving across the shield-can during a deposition, the film thickness is directly proportional to the length of the opening on the can along the moving direction. By equating the summation of relative weighting to the required relative thickness at the same position, the length of the opening at that position can be determined. By repeating the same process for the whole length of the required profile, a contour can be obtained for a desired thickness profile. The contoured mask is then placed on the opening of the shield-can. The number of passes and the moving speed of the substrate are determined according to the required thickness and the growth-rate calibration. The mirror coating profile is determined from the ideal surface figure of a focus ellipse and that obtained

  13. Advanced satellite communication system

    NASA Technical Reports Server (NTRS)

    Staples, Edward J.; Lie, Sen

    1992-01-01

    The objective of this research program was to develop an innovative advanced satellite receiver/demodulator utilizing surface acoustic wave (SAW) chirp transform processor and coherent BPSK demodulation. The algorithm of this SAW chirp Fourier transformer is of the Convolve - Multiply - Convolve (CMC) type, utilizing off-the-shelf reflective array compressor (RAC) chirp filters. This satellite receiver, if fully developed, was intended to be used as an on-board multichannel communications repeater. The Advanced Communications Receiver consists of four units: (1) CMC processor, (2) single sideband modulator, (3) demodulator, and (4) chirp waveform generator and individual channel processors. The input signal is composed of multiple user transmission frequencies operating independently from remotely located ground terminals. This signal is Fourier transformed by the CMC Processor into a unique time slot for each user frequency. The CMC processor is driven by a waveform generator through a single sideband (SSB) modulator. The output of the coherent demodulator is composed of positive and negative pulses, which are the envelopes of the chirp transform processor output. These pulses correspond to the data symbols. Following the demodulator, a logic circuit reconstructs the pulses into data, which are subsequently differentially decoded to form the transmitted data. The coherent demodulation and detection of BPSK signals derived from a CMC chirp transform processor were experimentally demonstrated and bit error rate (BER) testing was performed. To assess the feasibility of such advanced receiver, the results were compared with the theoretical analysis and plotted for an average BER as a function of signal-to-noise ratio. Another goal of this SBIR program was the development of a commercial product. The commercial product developed was an arbitrary waveform generator. The successful sales have begun with the delivery of the first arbitrary waveform generator.

  14. Using quaternions to control assembly and adjustment mirror-prism optical systems

    NASA Astrophysics Data System (ADS)

    Ezhova, Kseniia; Zverev, Victor

    2015-06-01

    It is shown that the applying of quaternions can successfully solve the problem of determining the unit vector of the beam reflected from an arbitrary system of flat mirrors, and the position of the image of a point object formed by this system.

  15. Durability and reliability of lightweight composite mirrors for space optical systems

    NASA Astrophysics Data System (ADS)

    Willis, Paul B.; Coulter, Daniel R.

    1993-12-01

    Many future space optical systems are dependent on large apertures to achieve the collecting power or resolution necessary to meet mission goals. Traditional mirror materials such as glasses and metals result in optics which are heavy and costly to both fabricate and deploy. In recent years, an approach for fabricating large, lightweight, precision optics from fiber reinforced organic matrix composite materials has been developed and demonstrated. These mirror panels consist of composite facesheets bonded to an open cell core. A key element of this technology is the durability of the composite construction materials. Extensive testing has been performed on a number of composite materials based on carbon fiber and organic resins. Ultimately, a high modulus graphite fiber/cyanate ester composite system was chosen for the panel facesheets due to its superior mechanical properties, processability, thermal stability, radiation resistance, very low water absorption, and temporal stability. This program has successfully demonstrated the feasibility of fabricating space durable mirrors using composite materials technology.

  16. System and method for online inspection of turbines using an optical tube with broadspectrum mirrors

    SciTech Connect

    Baleine, Erwan

    2015-12-22

    An optical inspection system for nondestructive internal visual inspection and non-contact infra-red (IR) temperature monitoring of an online, operating power generation turbine. The optical inspection system includes an optical tube having a viewing port, at least one reflective mirror or a mirror array having a reflectivity spectral range from 550 nm to 20 .mu.m, and capable of continuous operation at temperatures greater than 932 degrees Fahrenheit (500 degrees Celsius), and a transparent window with high transmission within the same spectral range mounted distal the viewing port. The same optical mirror array may be used to measure selectively surface temperature of metal turbine blades in the near IR range (approximately 1 .mu.m wavelength) and of thermal barrier coated turbine blades in the long IR range (approximately 10 .mu.m wavelength).

  17. A technique for designing active control systems for astronomical telescope mirrors

    NASA Technical Reports Server (NTRS)

    Howell, W. E.; Creedon, J. F.

    1973-01-01

    The problem of designing a control system to achieve and maintain the required surface accuracy of the primary mirror of a large space telescope was considered. Control over the mirror surface is obtained through the application of a corrective force distribution by actuators located on the rear surface of the mirror. The design procedure is an extension of a modal control technique developed for distributed parameter plants with known eigenfunctions to include plants whose eigenfunctions must be approximated by numerical techniques. Instructions are given for constructing the mathematical model of the system, and a design procedure is developed for use with typical numerical data in selecting the number and location of the actuators. Examples of actuator patterns and their effect on various errors are given.

  18. A synthetic molecular system capable of mirror-image genetic replication and transcription.

    PubMed

    Wang, Zimou; Xu, Weiliang; Liu, Lei; Zhu, Ting F

    2016-07-01

    The overwhelmingly homochiral nature of life has left a puzzle as to whether mirror-image biological systems based on a chirally inverted version of molecular machinery could also have existed. Here we report that two key steps in the central dogma of molecular biology, the template-directed polymerization of DNA and transcription into RNA, can be catalysed by a chemically synthesized D-amino acid polymerase on an L-DNA template. We also show that two chirally mirrored versions of the 174-residue African swine fever virus polymerase X could operate in a racemic mixture without significant enantiomeric cross-inhibition to the activity of each other. Furthermore, we demonstrate that a functionally active L-DNAzyme could be enzymatically produced using the D-amino acid polymerase. The establishment of such molecular systems with an opposite handedness highlights the potential to exploit enzymatically produced mirror-image biomolecules as research and therapeutic tools. PMID:27325097

  19. Actuated Hybrid Mirror Telescope

    NASA Technical Reports Server (NTRS)

    Hickey, Gregory; Redding, David; Lowman, Andrew; Cohen, David; Ohara, Catherine

    2005-01-01

    The figure depicts the planned Actuated Hybrid Mirror Telescope (AHMT), which is intended to demonstrate a new approach to the design and construction of wide-aperture spaceborne telescopes for astronomy and Earth science. This technology is also appropriate for Earth-based telescopes. The new approach can be broadly summarized as using advanced lightweight mirrors that can be manufactured rapidly at relatively low cost. More specifically, it is planned to use precise replicated metallic nanolaminate mirrors to obtain the required high-quality optical finishes. Lightweight, dimensionally stable silicon carbide (SiC) structures will support the nanolaminate mirrors in the required surface figures. To enable diffraction- limited telescope performance, errors in surface figures will be corrected by use of mirror-shape-control actuators that will be energized, as needed, by a wave-front-sensing and control system. The concepts of nanolaminate materials and mirrors made from nanolaminate materials were discussed in several previous NASA Tech Briefs articles. Nanolaminates constitute a relatively new class of materials that can approach theoretical limits of stiffness and strength. Nanolaminate mirrors are synthesized by magnetron sputter deposition of metallic alloys and/or compounds on optically precise master surfaces to obtain optical-quality reflector surfaces backed by thin shell structures. As an integral part of the deposition process, a layer of gold that will constitute the reflective surface layer is deposited first, eliminating the need for a subsequent and separate reflective-coating process. The crystallographic textures of the nanolaminate will be controlled to optimize the performance of the mirror. The entire deposition process for making a nanolaminate mirror takes less than 100 hours, regardless of the mirror diameter. Each nanolaminate mirror will be bonded to its lightweight SiC supporting structure. The lightweight nanolaminate mirrors and Si

  20. At the limit of nondispersive micro and nanofocusing mirror optics.

    SciTech Connect

    Ice, G. E.; Specht, E. D.; Tischler, J. Z.; Khounsary, A.; Assoufid, L.; Liu, C.; Experimental Facilities Division; ORNL

    2004-01-01

    We describe x-ray Kirkpatrick-Baez mirror designs with the potential to produce hard x-ray beams of 40 nm or smaller. The x-ray quality mirrors required to achieve the desired performance can be fabricated by differential deposition on ultra-smooth surfaces, or by differential polishing. Various mirror systems designed for nanofocusing to {approx}40 nm and below are compared. The performance limits of total-external-reflection mirrors are compared with the limits of multilayer mirrors that can potentially focus to an even smaller spot size. The advantages of side-by-side Kirkpatrick-Baez mirrors are evaluated and more advanced, four-mirror systems with significantly greater geometrical demagnification are discussed. These systems can potentially reach 5 - 20 nm focal spot sizes for multilayer and total-external-reflection optics respectively.

  1. Autism and the mirror neuron system: insights from learning and teaching.

    PubMed

    Vivanti, Giacomo; Rogers, Sally J

    2014-01-01

    Individuals with autism have difficulties in social learning domains which typically involve mirror neuron system (MNS) activation. However, the precise role of the MNS in the development of autism and its relevance to treatment remain unclear. In this paper, we argue that three distinct aspects of social learning are critical for advancing knowledge in this area: (i) the mechanisms that allow for the implicit mapping of and learning from others' behaviour, (ii) the motivation to attend to and model conspecifics and (iii) the flexible and selective use of social learning. These factors are key targets of the Early Start Denver Model, an autism treatment approach which emphasizes social imitation, dyadic engagement, verbal and non-verbal communication and affect sharing. Analysis of the developmental processes and treatment-related changes in these different aspects of social learning in autism can shed light on the nature of the neuropsychological mechanisms underlying social learning and positive treatment outcomes in autism. This knowledge in turn may assist in developing more successful pedagogic approaches to autism spectrum disorder. Thus, intervention research can inform the debate on relations among neuropsychology of social learning, the role of the MNS, and educational practice in autism.

  2. Autism and the mirror neuron system: insights from learning and teaching

    PubMed Central

    Vivanti, Giacomo; Rogers, Sally J.

    2014-01-01

    Individuals with autism have difficulties in social learning domains which typically involve mirror neuron system (MNS) activation. However, the precise role of the MNS in the development of autism and its relevance to treatment remain unclear. In this paper, we argue that three distinct aspects of social learning are critical for advancing knowledge in this area: (i) the mechanisms that allow for the implicit mapping of and learning from others' behaviour, (ii) the motivation to attend to and model conspecifics and (iii) the flexible and selective use of social learning. These factors are key targets of the Early Start Denver Model, an autism treatment approach which emphasizes social imitation, dyadic engagement, verbal and non-verbal communication and affect sharing. Analysis of the developmental processes and treatment-related changes in these different aspects of social learning in autism can shed light on the nature of the neuropsychological mechanisms underlying social learning and positive treatment outcomes in autism. This knowledge in turn may assist in developing more successful pedagogic approaches to autism spectrum disorder. Thus, intervention research can inform the debate on relations among neuropsychology of social learning, the role of the MNS, and educational practice in autism. PMID:24778379

  3. Active optics: variable curvature mirrors for ELT laser guide star refocusing systems

    NASA Astrophysics Data System (ADS)

    Challita, Zalpha; Hugot, Emmanuel; Madec, Fabrice; Ferrari, Marc; Le Mignant, David; Vivès, Sébastien; Cuby, Jean-Gabriel

    2011-10-01

    The future generation of Extremely Large Telescopes will require a complex combination of technologies for adaptive optics (AO) systems assisted by laser guide stars (LGS). In this context, the distance from the LGS spot to the telescope pupil ranges from about 80 to 200 km, depending on the Sodium layer altitude and the elevation of the telescope. This variation leads to a defocusing effect on the LGS wave-front sensor which needs to be compensated. We propose an active mirror able to compensate for this variation, based on an original optical design including this active optics component. This LGS Variable Curvature Mirror (LGS-VCM) is a 120 mm spherical active mirror able to achieve 820 μm deflection sag with an optical quality better than 150 nm RMS, allowing the radius of curvature variation from F/12 to F/2. Based on elasticity theory, the deformation of the metallic mirror is provided by an air pressure applied on a thin meniscus with a variable thickness distribution. In this article, we detail the analytical development leading to the specific geometry of the active component, the results of finite element analysis and the expected performances in terms of surface error versus the range of refocalisation. Three prototypes have been manufactured to compare the real behavior of the mirror and the simulations data. Results obtained on the prototypes are detailed, showing that the deformation of the VCM is very close to the simulation, and leads to a realistic active concept.

  4. Laser Cleaning of Mirror Surface for Optical Diagnostic Systems of the ITER

    NASA Astrophysics Data System (ADS)

    Gubskii, K.; Kuznetsov, A.; Savchenkov, A.; Andreev, A.; Tugarinov, S.; Buzhinskij, O.

    The development of cleaning optics and deposition-mitigating techniques is a key factor in the construction and operation of optical diagnostics in ITER. The cleaning of optical surface by pulsed radiation from a fiber laser is an effective method that can recover optical properties of the mirror surface. The possibility of cleaning metallic mirrors from films with complex composition by pulsed radiation from a fiber laser has been experimentally researched. It has been shown that high initial reflection characteristics of optical elements can be recovered by choosing regimes of radiation effect on the deposited surface. Efficient cleaning is ensured by radiation with the power density of less than 107 W/cm2. At this relatively low power density, pollutions are removed in a solid phase and the thermal effect on the mirror is insignificant. Preliminary experiments of the metal mirrors cleaning by fiber laser radiation have demonstrated the possibility of hardware implementation techniques. Experiments on transport of laser radiation to the metal mirror by using a system of lens and cleaning showed the possibility of a hardware implementation of methods applicable in the geometry of the port-plug ITER.

  5. Advanced training systems

    NASA Technical Reports Server (NTRS)

    Savely, Robert T.; Loftin, R. Bowen

    1990-01-01

    Training is a major endeavor in all modern societies. Common training methods include training manuals, formal classes, procedural computer programs, simulations, and on-the-job training. NASA's training approach has focussed primarily on on-the-job training in a simulation environment for both crew and ground based personnel. NASA must explore new approaches to training for the 1990's and beyond. Specific autonomous training systems are described which are based on artificial intelligence technology for use by NASA astronauts, flight controllers, and ground based support personnel that show an alternative to current training systems. In addition to these specific systems, the evolution of a general architecture for autonomous intelligent training systems that integrates many of the features of traditional training programs with artificial intelligence techniques is presented. These Intelligent Computer Aided Training (ICAT) systems would provide much of the same experience that could be gained from the best on-the-job training.

  6. Status on NGST Mirror Technology

    NASA Technical Reports Server (NTRS)

    Jacobson, David

    2000-01-01

    NGST Mirror System Demonstrator (NMSD), in order to establish a benchmark for the state-of-the-art in lightweight optics and to establish credibility that the goals of NGST could be achieved. The past two years of the program has seen major steps in the development of several mirror materials, which not only might have NGST applicability but could also support other programs for other customers. Additionally, a second large mirror procurement, the Advanced Mirror System Demonstrator (AMSD), has been implemented providing a focal point to complete the mirror technology development and lead ultimately to the production of mirrors that will fly on NEXUS (the NGST flight experiment- discussed below) and NGST. This talk will focus on the mirror technology developed over the past 4 years on the NGST program.

  7. Freeform mirror polishing for compensation on non-symmetry system aberrations of remote sensing instrument

    NASA Astrophysics Data System (ADS)

    Kuo, Ching-Hsiang; Yu, Zong-Ru; Ho, Cheng-Fang; Hsu, Wei-Yao; Chen, Fong-Zhi

    2013-09-01

    Cassegrain optical systems are widely used in remote sensing instrument. Cassegrain telescope is composed of a primary mirror (M1), a secondary mirror (M2), and a set of correction lenses. The system aberrations of telescope could be corrected and balanced by M1 and M2. In the event of deformation of telescope assembly, the non-symmetry aberrations will be induced to the optical system and reduce the optical performance. The non-symmetry aberrations can be measured after completing M1 and M2 assembly and alignment processes. Compensating this identified error to M1 or M2 can improve the optical performance of the telescope system. The error compensation on M2 is more efficient due to its smaller aperture and quickly assembly and de-assembly processes. In this study, we map the system wavefront error caused by deformation of mirror supporting and gravity onto the designed aspheric surface of M2. The surface of M2 becomes a freeform from aspheric. The polishing process combines the techniques of conventional lapping and CNC polishing. We apply the conventional spherical lapping process to quick remove the sub-surface damage (SSD) layer and to get the accurate radius of best fit sphere of the designed aspheric surface with fine surface texture simultaneously. The polishing and metrology processes were performed by using Zeeko IRP1000 polisher and QED ASI. A Φ 150 mm mirror with freeform surface was completed.

  8. An experimental investigation of nonresonance photon accumulation in a system of spherical mirrors

    NASA Astrophysics Data System (ADS)

    Popov, S. S.; Atlukhanov, M. G.; Burdakov, A. V.; Ushkova, M. Yu.

    2016-07-01

    A new, nonresonant approach to photon accumulation in a system of two spherical mirrors is demonstrated experimentally. A high accumulation coefficient is obtained experimentally, and sufficient efficiency of this technique for application in such areas as spectroscopy, photochemistry, and photon neutralization of negative-ion beams is demonstrated. The photon accumulation efficiency is determined mainly by mirror reflectivity. It is nearly independent of the quality of the coupled-in radiation and does not require very high precision in aligning optical elements. The experimentally obtained data agree with theoretical calculations.

  9. Advanced synchronous luminescence system

    DOEpatents

    Vo-Dinh, Tuan

    1997-01-01

    A method and apparatus for determining the condition of tissue or otherwise making chemical identifications includes exposing the sample to a light source, and using a synchronous luminescence system to produce a spectrum that can be analyzed for tissue condition.

  10. Advanced Operating System Technologies

    NASA Astrophysics Data System (ADS)

    Cittolin, Sergio; Riccardi, Fabio; Vascotto, Sandro

    In this paper we describe an R&D effort to define an OS architecture suitable for the requirements of the Data Acquisition and Control of an LHC experiment. Large distributed computing systems are foreseen to be the core part of the DAQ and Control system of the future LHC experiments. Neworks of thousands of processors, handling dataflows of several gigaBytes per second, with very strict timing constraints (microseconds), will become a common experience in the following years. Problems like distributyed scheduling, real-time communication protocols, failure-tolerance, distributed monitoring and debugging will have to be faced. A solid software infrastructure will be required to manage this very complicared environment, and at this moment neither CERN has the necessary expertise to build it, nor any similar commercial implementation exists. Fortunately these problems are not unique to the particle and high energy physics experiments, and the current research work in the distributed systems field, especially in the distributed operating systems area, is trying to address many of the above mentioned issues. The world that we are going to face in the next ten years will be quite different and surely much more interconnected than the one we see now. Very ambitious projects exist, planning to link towns, nations and the world in a single "Data Highway". Teleconferencing, Video on Demend, Distributed Multimedia Applications are just a few examples of the very demanding tasks to which the computer industry is committing itself. This projects are triggering a great research effort in the distributed, real-time micro-kernel based operating systems field and in the software enginering areas. The purpose of our group is to collect the outcame of these different research efforts, and to establish a working environment where the different ideas and techniques can be tested, evaluated and possibly extended, to address the requirements of a DAQ and Control System suitable for LHC

  11. Advanced Data Acquisition Systems

    NASA Technical Reports Server (NTRS)

    Perotti, J.

    2003-01-01

    Current and future requirements of the aerospace sensors and transducers field make it necessary for the design and development of new data acquisition devices and instrumentation systems. New designs are sought to incorporate self-health, self-calibrating, self-repair capabilities, allowing greater measurement reliability and extended calibration cycles. With the addition of power management schemes, state-of-the-art data acquisition systems allow data to be processed and presented to the users with increased efficiency and accuracy. The design architecture presented in this paper displays an innovative approach to data acquisition systems. The design incorporates: electronic health self-check, device/system self-calibration, electronics and function self-repair, failure detection and prediction, and power management (reduced power consumption). These requirements are driven by the aerospace industry need to reduce operations and maintenance costs, to accelerate processing time and to provide reliable hardware with minimum costs. The project's design architecture incorporates some commercially available components identified during the market research investigation like: Field Programmable Gate Arrays (FPGA) Programmable Analog Integrated Circuits (PAC IC) and Field Programmable Analog Arrays (FPAA); Digital Signal Processing (DSP) electronic/system control and investigation of specific characteristics found in technologies like: Electronic Component Mean Time Between Failure (MTBF); and Radiation Hardened Component Availability. There are three main sections discussed in the design architecture presented in this document. They are the following: (a) Analog Signal Module Section, (b) Digital Signal/Control Module Section and (c) Power Management Module Section. These sections are discussed in detail in the following pages. This approach to data acquisition systems has resulted in the assignment of patent rights to Kennedy Space Center under U.S. patent # 6

  12. A Human Mirror Neuron System for Language: Perspectives from Signed Languages of the Deaf

    ERIC Educational Resources Information Center

    Knapp, Heather Patterson; Corina, David P.

    2010-01-01

    Language is proposed to have developed atop the human analog of the macaque mirror neuron system for action perception and production [Arbib M.A. 2005. From monkey-like action recognition to human language: An evolutionary framework for neurolinguistics (with commentaries and author's response). "Behavioral and Brain Sciences, 28", 105-167; Arbib…

  13. The Mirror Neuron System and Observational Learning: Implications for the Effectiveness of Dynamic Visualizations

    ERIC Educational Resources Information Center

    van Gog, Tamara; Paas, Fred; Marcus, Nadine; Ayres, Paul; Sweller, John

    2009-01-01

    Learning by observing and imitating others has long been recognized as constituting a powerful learning strategy for humans. Recent findings from neuroscience research, more specifically on the mirror neuron system, begin to provide insight into the neural bases of learning by observation and imitation. These findings are discussed here, along…

  14. Speech-Associated Gestures, Broca's Area, and the Human Mirror System

    ERIC Educational Resources Information Center

    Skipper, Jeremy I.; Goldin-Meadow, Susan; Nusbaum, Howard C.; Small, Steven L.

    2007-01-01

    Speech-associated gestures are hand and arm movements that not only convey semantic information to listeners but are themselves actions. Broca's area has been assumed to play an important role both in semantic retrieval or selection (as part of a language comprehension system) and in action recognition (as part of a "mirror" or…

  15. Plasma injection and capture at electron cyclotron resonance in a mirror system with additional rf fields

    SciTech Connect

    Golovanivskii, K.S.; Dugar-Zhabon, V.D.; Karyaka, V.I.; Milant'ev, V.P.; Turikov, V.A.

    1980-03-01

    Experiments and numerical simulations have been carried out to determine how cyclotron-resonance rf fields in an open magnetic mirror system affect the capture and confinement of a plasma injected along the axis. The results show that at electron cyclotron resonance the fields greatly improve the longitudinal plasma confinement.

  16. Two-axis Beam Steering Mirror Control system for Precision Pointing and Tracking Applications

    SciTech Connect

    Ulander, Klaus

    2006-01-01

    Precision pointing and tracking of laser beams is critical in numerous military and industrial applications. This is particularly true for systems requiring atmospheric beam propagation. Such systems are plagued by environmental influences which cause the optical signal to break up and wander. Example applications include laser communications, precision targeting, active imaging, chemical remote sensing, and laser vibrometry. The goal of this project is to build a beam steering system using a two-axis mirror to maintain precise pointing control. Ultimately, position control to 0.08% accuracy (40 {micro}rad) with a bandwidth of 200 Hz is desired. The work described encompasses evaluation of the instrumentation system and the subsequent design and implementation of an analog electronic controller for a two-axis mirror used to steer the beam. The controller operates over a wide temperature range, through multiple mirror resonances, and is independent of specific mirrors. The design was built and successfully fielded in a Lawrence Livermore National Laboratory free-space optics experiment. All measurements and performance parameters are derived from measurements made on actual hardware that was built and field tested. In some cases, specific design details have been omitted that involve proprietary information pertaining to Lawrence Livermore National Laboratory patent positions and claims. These omissions in no way impact the general validity of the work or concepts presented in this thesis.

  17. Advanced synchronous luminescence system

    DOEpatents

    Vo-Dinh, T.

    1997-02-04

    A method and apparatus are disclosed for determining the condition of tissue or otherwise making chemical identifications includes exposing the sample to a light source, and using a synchronous luminescence system to produce a spectrum that can be analyzed for tissue condition. 14 figs.

  18. Power Systems Advanced Research

    SciTech Connect

    California Institute of Technology

    2007-03-31

    In the 17 quarters of the project, we have accomplished the following milestones - first, construction of the three multiwavelength laser scattering machines for different light scattering study purposes; second, build up of simulation software package for simulation of field and laboratory particulates matters data; third, carried out field online test on exhaust from combustion engines with our laser scatter system. This report gives a summary of the results and achievements during the project's 16 quarters period. During the 16 quarters of this project, we constructed three multiwavelength scattering instruments for PM2.5 particulates. We build up a simulation software package that could automate the simulation of light scattering for different combinations of particulate matters. At the field test site with our partner, Alturdyne, Inc., we collected light scattering data for a small gas turbine engine. We also included the experimental data feedback function to the simulation software to match simulation with real field data. The PM scattering instruments developed in this project involve the development of some core hardware technologies, including fast gated CCD system, accurately triggered Passively Q-Switched diode pumped lasers, and multiwavelength beam combination system. To calibrate the scattering results for liquid samples, we also developed the calibration system which includes liquid PM generator and size sorting instrument, i.e. MOUDI. In this report, we give the concise summary report on each of these subsystems development results.

  19. Advanced imaging communication system

    NASA Technical Reports Server (NTRS)

    Hilbert, E. E.; Rice, R. F.

    1977-01-01

    Key elements of system are imaging and nonimaging sensors, data compressor/decompressor, interleaved Reed-Solomon block coder, convolutional-encoded/Viterbi-decoded telemetry channel, and Reed-Solomon decoding. Data compression provides efficient representation of sensor data, and channel coding improves reliability of data transmission.

  20. Westinghouse advanced particle filter system

    SciTech Connect

    Lippert, T.E.; Bruck, G.J.; Sanjana, Z.N.; Newby, R.A.

    1995-11-01

    Integrated Gasification Combined Cycles (IGCC), Pressurized Fluidized Bed Combustion (PFBC) and Advanced PFBC (APFB) are being developed and demonstrated for commercial power generation application. Hot gas particulate filters are key components for the successful implementation of IGCC, PFBC and APFB in power generation gas turbine cycles. The objective of this work is to develop and qualify through analysis and testing a practical hot gas ceramic barrier filter system that meets the performance and operational requirements of these advanced, solid fuel power generation cycles.

  1. Data management system advanced architectures

    NASA Technical Reports Server (NTRS)

    Chevers, ED

    1991-01-01

    The topics relating to the Space Station Freedom (SSF) are presented in view graph form and include: (1) the data management system (DMS) concept; (2) DMS evolution rationale; (3) the DMS advance architecture task; (4) DMS group support for Ames payloads; (5) DMS testbed development; (6) the DMS architecture task status; (7) real time multiprocessor testbed; (8) networked processor performance; (9) and the DMS advance architecture task 1992 goals.

  2. The 8.2 metre primary mirrors of the VLT

    NASA Astrophysics Data System (ADS)

    Dierickx, P.; Enard, D.; Merkle, F.; Noethe, L.; Wilson, R. N.

    1990-08-01

    The Very Large Telescope (VLT) presently being developed at ESO is described in terms of technological advances which make its use both technically effective and feasible. The VLT capitalizes on advances in materials, polishing techniques, and mirror support systems. The VLT consists of four 8-m alt-az telescopes and a 2-m auxiliary telescope in a single-dish configuration with Zerodur meniscus mirrors passively supported on a lateral system. A discussion of the tradeoffs between glass and metal mirrors is presented, and computerized polishing is described in relation to optical specifications. The mirror is supported with 150 axial and 60 lateral supports with electromechanical actuators to modulate applied force. The active optics concept is employed via the flexibility of the primary mirror, which generates elastomechanical deformations and the position and orientation of the secondary mirror.

  3. Advanced flight control system study

    NASA Technical Reports Server (NTRS)

    Mcgough, J.; Moses, K.; Klafin, J. F.

    1982-01-01

    The architecture, requirements, and system elements of an ultrareliable, advanced flight control system are described. The basic criteria are functional reliability of 10 to the minus 10 power/hour of flight and only 6 month scheduled maintenance. A distributed system architecture is described, including a multiplexed communication system, reliable bus controller, the use of skewed sensor arrays, and actuator interfaces. Test bed and flight evaluation program are proposed.

  4. Study on measurement of 160 mm convex hyperbolic mirror for Cassegrain reflecting system

    NASA Astrophysics Data System (ADS)

    Ho, Cheng-Fang; Yu, Zong-Ru; Kuo, Ching-Hsiang; Hsu, Wei-Yao

    2012-10-01

    In this study, the measurement of a 160 mm convex hyperbolic mirror by using the 6 inches phase shifting interferometer and the CGH (computer-generated hologram) in a vertical setup is presented. The wavefront errors of the metrology system including the reference flat and CGH flat due to gravity effect are measured and calibrated by using random testing and null cavity testing with and without CGH. Then, the real form error of each single sub-aperture could be acquired by subtracting the system wavefront errors. In this study, we measured form errors of 10 off-axis sub-apertures with equal angle space and then stitched them to establish the whole irregularity in the shape of the mirror in 160 mm diameter. Finally, we imported the irregularity in the shape of the mirror to the CNC aspheric polishing machine for correction polishing. Combining the aspheric metrology technique and the CNC aspheric polishing technique, a 160 mm secondary mirror for the Cassegrain reflecting system was finished within PV 0.15μm and RMS 17.9 nm.

  5. Do you mean me? Communicative intentions recruit the mirror and the mentalizing system.

    PubMed

    Ciaramidaro, Angela; Becchio, Cristina; Colle, Livia; Bara, Bruno G; Walter, Henrik

    2014-07-01

    Being able to comprehend communicative intentions and to recognize whether such intentions are directed toward us or not is extremely important in social interaction. Two brain systems, the mentalizing and the mirror neuron system, have been proposed to underlie intention recognition. However, little is still known about how the systems cooperate within the process of communicative intention understanding and to what degree they respond to self-directed and other-directed stimuli. To investigate the role of the mentalizing and the mirror neuron system, we used functional magnetic resonance imaging with four types of action sequence: communicative and private intentions as well as other-directed and self-directed intentions. Categorical and functional connectivity analyses showed that both systems contribute to the encoding of communicative intentions and that both systems are significantly stronger activated and more strongly coupled in self-directed communicative actions.

  6. MEMS Actuated Deformable Mirror

    SciTech Connect

    Papavasiliou, A; Olivier, S; Barbee, T; Walton, C; Cohn, M

    2005-11-10

    This ongoing work concerns the creation of a deformable mirror by the integration of MEMS actuators with Nanolaminate foils through metal compression boning. These mirrors will use the advantages of these disparate technologies to achieve dense actuation of a high-quality, continuous mirror surface. They will enable advanced adaptive optics systems in large terrestrial telescopes. While MEMS actuators provide very dense actuation with high precision they can not provide large forces typically necessary to deform conventional mirror surfaces. Nanolaminate foils can be fabricated with very high surface quality while their extraordinary mechanical properties enable very thin, flexible foils to survive the rigors of fabrication. Precise metal compression bonding allows the attachment of the fragile MEMS actuators to the thin nanolaminate foils without creating distortions at the bond sites. This paper will describe work in four major areas: (1) modeling and design, (2) bonding development, (3) nanolaminate foil development, (4) producing a prototype. A first-principles analytical model was created and used to determine the design parameters. A method of bonding was determined that is both strong, and minimizes the localized deformation or print through. Work has also been done to produce nanolaminate foils that are sufficiently thin, flexible and flat to be deformed by the MEMS actuators. Finally a prototype was produced by bonding thin, flexible nanolaminate foils to commercially available MEMS actuators.

  7. [Mirror behaviors in dementia: the many mirror signs].

    PubMed

    Ghika, Joseph; Diéguez, Sebastian; Assal, Frédéric; Demonet, Jean-François

    2013-11-13

    Mirror behaviors in advanced dementia are: the mirror sign of Abely and Delmas, where the patient stares at his face (environment-driven behavior of Lhermitte); non recognition of the self in the mirror (autoprosopagnosia and/or delirious auto-Capgras); mirror agnosia of Ramachandran and Binkofski where the patient do not understand the concept of mirror and its use; the psychovisual reflex, or reflex pursuit of the eyes when passively moving a minrror in front of a patient (intact vision); mirror writing (procedural learning). We describe four demented patients with mirror behaviors assessing brain mechanisms of self recognition, social brain and mental and visuo-spatial manipulation of images and objects.

  8. An updated T-series thermocouple measurement system for high-accuracy temperature measurements of the MMT primary mirror

    NASA Astrophysics Data System (ADS)

    Clark, D.; Gibson, J. D.

    2012-09-01

    Starting in 2009, MMTO began design and installation of a new set of electronics to measure a set of radiallydistributed type T thermocouples installed after the primary mirror polishing was completed. These thermocouples are arranged in both single measurement points and as thermopiles for differential temperature sensing. Since the goal of the primary mirror temperature control system is to minimize mirror seeing and mirror figure errors induced by temperature variation across the primary mirror, it depends on excellent accuracy from the temperature sensing system. The new electronics encompass on-board cold-junction compensation, real-time ITS-90 curve fitting, and Ethernet connectivity to the data servers running in the MMTO software infrastructure. We describe the hardware design, system wiring, and software used in this system.

  9. Is the human mirror neuron system plastic? Evidence from a transcranial magnetic stimulation study.

    PubMed

    Mehta, Urvakhsh Meherwan; Waghmare, Avinash V; Thirthalli, Jagadisha; Venkatasubramanian, Ganesan; Gangadhar, Bangalore N

    2015-10-01

    Virtual lesions in the mirror neuron network using inhibitory low-frequency (1Hz) transcranial magnetic stimulation (TMS) have been employed to understand its spatio-functional properties. However, no studies have examined the influence of neuro-enhancement by using excitatory high-frequency (20Hz) repetitive transcranial magnetic stimulation (HF-rTMS) on these networks. We used three forms of TMS stimulation (HF-rTMS, single and paired pulse) to investigate whether the mirror neuron system facilitates the motor system during goal-directed action observation relative to inanimate motion (motor resonance), a marker of putative mirror neuron activity. 31 healthy individuals were randomized to receive single-sessions of true or sham HF-rTMS delivered to the left inferior frontal gyrus - a component of the human mirror system. Motor resonance was assessed before and after HF-rTMS using three TMS cortical reactivity paradigms: (a) 120% of resting motor threshold (RMT), (b) stimulus intensity set to evoke motor evoked potential of 1-millivolt amplitude (SI1mV) and (c) a short latency paired pulse paradigm. Two-way RMANOVA showed a significant group (true versus sham) X occasion (pre- and post-HF-rTMS motor resonance) interaction effect for SI1mV [F(df)=6.26 (1, 29), p=0.018] and 120% RMT stimuli [F(df)=7.01 (1, 29), p=0.013] indicating greater enhancement of motor resonance in the true HF-rTMS group than the sham-group. This suggests that HF-rTMS could adaptively modulate properties of the mirror neuron system. This neuro-enhancement effect is a preliminary step that can open translational avenues for novel brain stimulation therapeutics targeting social-cognition deficits in schizophrenia and autism. PMID:26194133

  10. Is the human mirror neuron system plastic? Evidence from a transcranial magnetic stimulation study.

    PubMed

    Mehta, Urvakhsh Meherwan; Waghmare, Avinash V; Thirthalli, Jagadisha; Venkatasubramanian, Ganesan; Gangadhar, Bangalore N

    2015-10-01

    Virtual lesions in the mirror neuron network using inhibitory low-frequency (1Hz) transcranial magnetic stimulation (TMS) have been employed to understand its spatio-functional properties. However, no studies have examined the influence of neuro-enhancement by using excitatory high-frequency (20Hz) repetitive transcranial magnetic stimulation (HF-rTMS) on these networks. We used three forms of TMS stimulation (HF-rTMS, single and paired pulse) to investigate whether the mirror neuron system facilitates the motor system during goal-directed action observation relative to inanimate motion (motor resonance), a marker of putative mirror neuron activity. 31 healthy individuals were randomized to receive single-sessions of true or sham HF-rTMS delivered to the left inferior frontal gyrus - a component of the human mirror system. Motor resonance was assessed before and after HF-rTMS using three TMS cortical reactivity paradigms: (a) 120% of resting motor threshold (RMT), (b) stimulus intensity set to evoke motor evoked potential of 1-millivolt amplitude (SI1mV) and (c) a short latency paired pulse paradigm. Two-way RMANOVA showed a significant group (true versus sham) X occasion (pre- and post-HF-rTMS motor resonance) interaction effect for SI1mV [F(df)=6.26 (1, 29), p=0.018] and 120% RMT stimuli [F(df)=7.01 (1, 29), p=0.013] indicating greater enhancement of motor resonance in the true HF-rTMS group than the sham-group. This suggests that HF-rTMS could adaptively modulate properties of the mirror neuron system. This neuro-enhancement effect is a preliminary step that can open translational avenues for novel brain stimulation therapeutics targeting social-cognition deficits in schizophrenia and autism.

  11. Advanced Dewatering Systems Development

    SciTech Connect

    R.H. Yoon; G.H. Luttrell

    2008-07-31

    A new fine coal dewatering technology has been developed and tested in the present work. The work was funded by the Solid Fuels and Feedstocks Grand Challenge PRDA. The objective of this program was to 'develop innovative technical approaches to ensure a continued supply of environmentally sound solid fuels for existing and future combustion systems with minimal incremental fuel cost.' Specifically, this solicitation is aimed at developing technologies that can (i) improve the efficiency or economics of the recovery of carbon when beneficiating fine coal from both current production and existing coal slurry impoundments and (ii) assist in the greater utilization of coal fines by improving the handling characteristics of fine coal via dewatering and/or reconstitution. The results of the test work conducted during Phase I of the current project demonstrated that the new dewatering technologies can substantially reduce the moisture from fine coal, while the test work conducted during Phase II successfully demonstrated the commercial viability of this technology. It is believed that availability of such efficient and affordable dewatering technology is essential to meeting the DOE's objectives.

  12. Exposure uniformity analysis and optimization for scanning mirror system in Hefei lithography beam line

    NASA Astrophysics Data System (ADS)

    Guo, Congliang; Yin, Chuanshi; Liu, Tonghui; Zhong, Aijuan; Qian, Shinan

    2001-10-01

    It is a new technology to use synchrotron radiation lithography for making large scale integral circuit. Synchrotron radiation lithography System is composed of lithography beam line and exposure chamber. A scanning mirror system is making the largest linear exposure area for integrate circuit. By means of increasing control fineness and optimizing scanning frequency in on-line control system, the uniformity of exposure grating is improved quite well. It is opening good idea for every scientist and technician to continue study. It is shown that inspect and control system is still reliable, noise reduced and very convenient after several years operation. It shows operating status of each equipment and vacuum figures on beam line and station, mirror scanning linearity, exposure time, beam current, and so on. Some successful soft X-ray lithography sub-micrometer results are achieved by different users in this system, they are showing very good resolution, more clear leakage and enough depth for example. A convenient and smart optimum analysis system will be developed soon. It is easy to find very good oscillation frequency for mirror vibrating, and the strong interference from current monitor in synchrotron radiation storage ring is reduced very well. Convenient, compact, reliability and safety are the basic but important idea of system design, and what is higher level consideration for getting fine result of micro lithography. There will have enough database space for a different kind user to storage on- line test datum in system.

  13. The cortical mirror system reflects the cortical motor system. Comment on "Grasping synergies: A motor-control approach to the mirror neuron mechanism" by A. D'Ausilio et al.

    NASA Astrophysics Data System (ADS)

    Naish, Katherine R.; Holmes, Nicholas P.

    2015-03-01

    Mirror neurons - cells that are active during both the execution and observation of actions - have been implicated in a wide range of functions. It was originally suggested that these interesting cells play a role in the ability to understand the actions of others [2]. While there are strong arguments against the mirror system being the only mechanism underlying our ability to interpret others' actions (e.g., [4]), it may well play a contributory role. One important constraint on the role that the mirror system could play in action understanding is the extent to which the observed action and the mirror representation match each other. To use the mirror analogy: how closely does the reflection resemble the subject standing in front of it?

  14. Primary Mirror Figure Maintenance of the Hobby-Eberly Telescope using the Segment Alignment Maintenance System

    NASA Technical Reports Server (NTRS)

    Rakoczy, John; Hall, Drew; Howard, Ricky; Ly, William; Weir, John; Montgomery, Edward; Brantley, Lott W. (Technical Monitor)

    2002-01-01

    The Segment Alignment Maintenance System (SAMs) was installed on McDonald Observatory's Hobby-Eberly Telescope (HET) in August 2001. The SAMs became fully operational in October 2001. The SAMs uses a system of 480 inductive edge sensors to correct misalignments of the HET's 91 primary mirror segments when the segments are perturbed from their aligned reference positions. A special observer estimated and corrects for the global radius of curvature (GroC) mode, a mode unobservable by the edge sensors. The SAMs edge sensor system and (GroC) estimator are able to maintain HET's primary figure for much longer durations than previously had been observed. Telescope image quality has improved, and the amount of overhead time required from primary mirror alignment has been reduced. This paper gives a functional description of the SAMs control system and presents performance verification data. This paper also describes how the SAMs has improved the operational efficiency of the HET.

  15. Vectorial velocity filter for ultracold neutrons based on a surface-disordered mirror system.

    PubMed

    Chizhova, L A; Rotter, S; Jenke, T; Cronenberg, G; Geltenbort, P; Wautischer, G; Filter, H; Abele, H; Burgdörfer, J

    2014-03-01

    We perform classical three-dimensional Monte Carlo simulations of ultracold neutrons scattering through an absorbing-reflecting mirror system in the Earth's gravitational field. We show that the underlying mixed phase space of regular skipping motion and random motion due to disorder scattering can be exploited to realize a vectorial velocity filter for ultracold neutrons. The absorbing-reflecting mirror system proposed allows beams of ultracold neutrons with low angular divergence to be formed. The range of velocity components can be controlled by adjusting the geometric parameters of the system. First experimental tests of its performance are presented. One potential future application is the investigation of transport and scattering dynamics in confined systems downstream of the filter.

  16. A microwave tomography system using a tunable mirror for beam steering

    SciTech Connect

    Tayebi, A.; Tang, J.; Paladhi, P. Roy; Udpa, L.; Udpa, S.

    2014-02-18

    Microwave tomography is a fast-growing technique in the fields of NDE and medical industry. This paper presents a new microwave tomography system which reduces the complexities of conventional microwave imaging systems by utilizing a reconfigurable mirror, a tunable reflectarray antenna. In order to build a tunable reflectarray with beam steering capabilities, the unit cell characteristics should dynamically alter. Modelling and experimental results of a single unit cell are presented in this work.

  17. Mirror fusion test facility magnet system. Final design report

    SciTech Connect

    Henning, C.D.; Hodges, A.J.; VanSant, J.H.; Dalder, E.N.; Hinkle, R.E.; Horvath, J.A.; Scanlan, R.M.; Shimer, D.W.; Baldi, R.W.; Tatro, R.E.

    1980-09-03

    Information is given on each of the following topics: (1) magnet description, (2) superconducting manufacture, (3) mechanical behavior of conductor winding, (4) coil winding, (5) thermal analysis, (6) cryogenic system, (7) power supply system, (8) structural analysis, (9) structural finite element analysis refinement, (10) structural case fault analysis, and (11) structural metallurgy. (MOW)

  18. Advanced spacecraft fuel cell systems

    NASA Technical Reports Server (NTRS)

    Thaller, L. H.

    1972-01-01

    The development and characteristics of advanced spacecraft fuel cell systems are discussed. The system is designed to operate on low pressure, propulsion grade hydrogen and oxygen. The specific goals are 10,000 hours of operation with refurbishment, 20 pounds per kilowatt at a sustained power of 7 KW, and 21 KW peaking capability for durations of two hours. The system rejects waste heat to the spacecraft cooling system at power levels up to 7 KW. At higher powers, the system automatically transfers to open cycle operation with overboard steam venting.

  19. ADVANCED GAS TURBINE SYSTEMS RESEARCH

    SciTech Connect

    Unknown

    2000-01-01

    The activities of the Advanced Gas Turbine Systems Research (AGRSR) program are described in the quarterly report. The report is divided into discussions of Membership, Administration, Technology Transfer (Workshop/Education) and Research. Items worthy of note are presented in extended bullet format following the appropriate heading.

  20. Advances in percutaneous electrode systems.

    PubMed

    Mooney, V; Roth, A M

    1976-01-01

    In the past eight years, developing a percutaneous electrode system has advanced to a successful, yet simple, method to transmit electrical signals, overcoming the serious problems of excessive mechanical irritation at the skin interface. Experience with over 50-74% in the clinical applications of 1) chronic pain relief; 2) contracture correction; and 3) sensory feedback.

  1. ADVANCED GAS TURBINE SYSTEMS RESEARCH

    SciTech Connect

    Unknown

    2002-04-01

    The activities of the Advanced Gas Turbine Systems Research (AGTSR) program for this reporting period are described in this quarterly report. The report is divided into discussions of Membership, Administration, Technology Transfer (Workshop/Education), Research and Miscellaneous Related Activity. Items worthy of note are presented in extended bullet format following the appropriate heading.

  2. ADVANCED GAS TURBINE SYSTEMS RESEARCH

    SciTech Connect

    Unknown

    2002-02-01

    The activities of the Advanced Gas Turbine Systems Research (AGTSR) program for this reporting period are described in this quarterly report. The report is divided into discussions of Membership, Administration, Technology Transfer (Workshop/Education), Research and Miscellaneous Related Activity. Items worthy of note are presented in extended bullet format following the appropriate heading.

  3. Involvement of the mirror neuron system in blunted affect in schizophrenia.

    PubMed

    Lee, Jung Suk; Chun, Ji Won; Yoon, Sang Young; Park, Hae-Jeong; Kim, Jae-Jin

    2014-01-01

    Blunted affect is a relatively enduring schizophrenic symptom and its presence brings about poor functioning and outcomes. Functional impairment in the mirror neuron system which is involved in both motor execution and imitation may be a neural basis of blunted affect, but it is not proved yet. Fifteen patients with schizophrenia and 16 healthy controls performed the facial expression task during functional magnetic resonance imaging. The task was to reproduce facial expressions in response to the face or word stimuli for happiness, sadness, and meaningless expression. Brain activities during facial expressions in patients compared with controls and their relationship with affective flattening were analyzed. Compared to controls, patients exhibited decreased activity in the widespread dorsal frontal regions and increased activity in the ventral frontal and subcortical regions. Patients also demonstrated significant negative correlation of the severity of affective flattening with activities in the mirror neuron system, such as the premotor cortex, motor cortex, and inferior parietal lobule. Emotional expression in patients with schizophrenia may be related to hypoactivity of the dorsal system and hyperactivity of the ventral system. An imbalance of these two systems may contribute to blunted affect. Directly addressing blunted affect using emotional expression provides a new perspective that functional disturbance of the mirror neuron system may play an important role in manifestation of blunted affect in schizophrenia.

  4. Advanced turboprop testbed systems study

    NASA Technical Reports Server (NTRS)

    Goldsmith, I. M.

    1982-01-01

    The proof of concept, feasibility, and verification of the advanced prop fan and of the integrated advanced prop fan aircraft are established. The use of existing hardware is compatible with having a successfully expedited testbed ready for flight. A prop fan testbed aircraft is definitely feasible and necessary for verification of prop fan/prop fan aircraft integrity. The Allison T701 is most suitable as a propulsor and modification of existing engine and propeller controls are adequate for the testbed. The airframer is considered the logical overall systems integrator of the testbed program.

  5. OPTIMIZATION OF ADVANCED FILTER SYSTEMS

    SciTech Connect

    R.A. Newby; G.J. Bruck; M.A. Alvin; T.E. Lippert

    1998-04-30

    Reliable, maintainable and cost effective hot gas particulate filter technology is critical to the successful commercialization of advanced, coal-fired power generation technologies, such as IGCC and PFBC. In pilot plant testing, the operating reliability of hot gas particulate filters have been periodically compromised by process issues, such as process upsets and difficult ash cake behavior (ash bridging and sintering), and by design issues, such as cantilevered filter elements damaged by ash bridging, or excessively close packing of filtering surfaces resulting in unacceptable pressure drop or filtering surface plugging. This test experience has focused the issues and has helped to define advanced hot gas filter design concepts that offer higher reliability. Westinghouse has identified two advanced ceramic barrier filter concepts that are configured to minimize the possibility of ash bridge formation and to be robust against ash bridges should they occur. The ''inverted candle filter system'' uses arrays of thin-walled, ceramic candle-type filter elements with inside-surface filtering, and contains the filter elements in metal enclosures for complete separation from ash bridges. The ''sheet filter system'' uses ceramic, flat plate filter elements supported from vertical pipe-header arrays that provide geometry that avoids the buildup of ash bridges and allows free fall of the back-pulse released filter cake. The Optimization of Advanced Filter Systems program is being conducted to evaluate these two advanced designs and to ultimately demonstrate one of the concepts in pilot scale. In the Base Contract program, the subject of this report, Westinghouse has developed conceptual designs of the two advanced ceramic barrier filter systems to assess their performance, availability and cost potential, and to identify technical issues that may hinder the commercialization of the technologies. A plan for the Option I, bench-scale test program has also been developed based

  6. Grating exchange system of independent mirror supported by floating rotary stage

    NASA Astrophysics Data System (ADS)

    Zhang, Jianhuan; Tao, Jin; Liu, Yan; Nan, Yan

    2015-10-01

    The performance of The Grating Exchange System can satisfy the Thirty Meter Telescope - TMT for astronomical observation WFOS index requirements and satisfy the requirement of accuracy in the grating exchange. It is used to install in the MOBIE and a key device of MOBIE. The Wide Field Optical Spectrograph (WFOS) is one of the three first-light observing capabilities selected by the TMT Science Advisory Committee. The Multi-Object Broadband Imaging Echellette (MOBIE) instrument design concept has been developed to address the WFOS requirements as described in the TMT Science-Based Requirements Document (SRD). The Grating Exchange System uses a new type of separate movement way of three grating devices and a mirror device. Three grating devices with a mirror are able to achieve independence movement. This kind of grating exchange system can effectively solve the problem that the volume of the grating change system is too large and that the installed space of MOBIE instruments is too limit. This system adopts the good stability, high precision of rotary stage - a kind of using air bearing (Air bearing is famous for its ultra-high precision, and can meet the optical accuracy requirement) and rotation positioning feedback gauge turntable to support grating device. And with a kind of device which can carry greater weight bracket fixed on the MOBIE instrument, with two sets of servo motor control rotary stage and the mirror device respectively. And we use the control program to realize the need of exercising of the grating device and the mirror device. Using the stress strain analysis software--SolidWorks for stress and strain analysis of this structure. And then checking the structure of the rationality and feasibility. And prove that this system can realize the positioning precision under different working conditions can meet the requirements of imaging optical grating diffraction efficiency and error by the calculation and optical performance analysis.

  7. Advanced Transport Operating Systems Program

    NASA Technical Reports Server (NTRS)

    White, John J.

    1990-01-01

    NASA-Langley's Advanced Transport Operating Systems Program employs a heavily instrumented, B 737-100 as its Transport Systems Research Vehicle (TRSV). The TRSV has been used during the demonstration trials of the Time Reference Scanning Beam Microwave Landing System (TRSB MLS), the '4D flight-management' concept, ATC data links, and airborne windshear sensors. The credibility obtainable from successful flight test experiments is often a critical factor in the granting of substantial commitments for commercial implementation by the FAA and industry. In the case of the TRSB MLS, flight test demonstrations were decisive to its selection as the standard landing system by the ICAO.

  8. Advanced Information Processing System (AIPS)

    NASA Technical Reports Server (NTRS)

    Pitts, Felix L.

    1993-01-01

    Advanced Information Processing System (AIPS) is a computer systems philosophy, a set of validated hardware building blocks, and a set of validated services as embodied in system software. The goal of AIPS is to provide the knowledgebase which will allow achievement of validated fault-tolerant distributed computer system architectures, suitable for a broad range of applications, having failure probability requirements of 10E-9 at 10 hours. A background and description is given followed by program accomplishments, the current focus, applications, technology transfer, FY92 accomplishments, and funding.

  9. View-Invariant Visuomotor Processing in Computational Mirror Neuron System for Humanoid.

    PubMed

    Dawood, Farhan; Loo, Chu Kiong

    2016-01-01

    Mirror neurons are visuo-motor neurons found in primates and thought to be significant for imitation learning. The proposition that mirror neurons result from associative learning while the neonate observes his own actions has received noteworthy empirical support. Self-exploration is regarded as a procedure by which infants become perceptually observant to their own body and engage in a perceptual communication with themselves. We assume that crude sense of self is the prerequisite for social interaction. However, the contribution of mirror neurons in encoding the perspective from which the motor acts of others are seen have not been addressed in relation to humanoid robots. In this paper we present a computational model for development of mirror neuron system for humanoid based on the hypothesis that infants acquire MNS by sensorimotor associative learning through self-exploration capable of sustaining early imitation skills. The purpose of our proposed model is to take into account the view-dependency of neurons as a probable outcome of the associative connectivity between motor and visual information. In our experiment, a humanoid robot stands in front of a mirror (represented through self-image using camera) in order to obtain the associative relationship between his own motor generated actions and his own visual body-image. In the learning process the network first forms mapping from each motor representation onto visual representation from the self-exploratory perspective. Afterwards, the representation of the motor commands is learned to be associated with all possible visual perspectives. The complete architecture was evaluated by simulation experiments performed on DARwIn-OP humanoid robot.

  10. View-Invariant Visuomotor Processing in Computational Mirror Neuron System for Humanoid

    PubMed Central

    Dawood, Farhan; Loo, Chu Kiong

    2016-01-01

    Mirror neurons are visuo-motor neurons found in primates and thought to be significant for imitation learning. The proposition that mirror neurons result from associative learning while the neonate observes his own actions has received noteworthy empirical support. Self-exploration is regarded as a procedure by which infants become perceptually observant to their own body and engage in a perceptual communication with themselves. We assume that crude sense of self is the prerequisite for social interaction. However, the contribution of mirror neurons in encoding the perspective from which the motor acts of others are seen have not been addressed in relation to humanoid robots. In this paper we present a computational model for development of mirror neuron system for humanoid based on the hypothesis that infants acquire MNS by sensorimotor associative learning through self-exploration capable of sustaining early imitation skills. The purpose of our proposed model is to take into account the view-dependency of neurons as a probable outcome of the associative connectivity between motor and visual information. In our experiment, a humanoid robot stands in front of a mirror (represented through self-image using camera) in order to obtain the associative relationship between his own motor generated actions and his own visual body-image. In the learning process the network first forms mapping from each motor representation onto visual representation from the self-exploratory perspective. Afterwards, the representation of the motor commands is learned to be associated with all possible visual perspectives. The complete architecture was evaluated by simulation experiments performed on DARwIn-OP humanoid robot. PMID:26998923

  11. View-Invariant Visuomotor Processing in Computational Mirror Neuron System for Humanoid.

    PubMed

    Dawood, Farhan; Loo, Chu Kiong

    2016-01-01

    Mirror neurons are visuo-motor neurons found in primates and thought to be significant for imitation learning. The proposition that mirror neurons result from associative learning while the neonate observes his own actions has received noteworthy empirical support. Self-exploration is regarded as a procedure by which infants become perceptually observant to their own body and engage in a perceptual communication with themselves. We assume that crude sense of self is the prerequisite for social interaction. However, the contribution of mirror neurons in encoding the perspective from which the motor acts of others are seen have not been addressed in relation to humanoid robots. In this paper we present a computational model for development of mirror neuron system for humanoid based on the hypothesis that infants acquire MNS by sensorimotor associative learning through self-exploration capable of sustaining early imitation skills. The purpose of our proposed model is to take into account the view-dependency of neurons as a probable outcome of the associative connectivity between motor and visual information. In our experiment, a humanoid robot stands in front of a mirror (represented through self-image using camera) in order to obtain the associative relationship between his own motor generated actions and his own visual body-image. In the learning process the network first forms mapping from each motor representation onto visual representation from the self-exploratory perspective. Afterwards, the representation of the motor commands is learned to be associated with all possible visual perspectives. The complete architecture was evaluated by simulation experiments performed on DARwIn-OP humanoid robot. PMID:26998923

  12. Caycedo's Sophrology and Lozanov's Suggestology: Mirror Images of a System.

    ERIC Educational Resources Information Center

    Bancroft, W. Jane

    In the 1960's, two medical doctors, Georgi Lozanov and Alfonso Caycedo, discovered independently that certain yogic techniques of physical and mental relaxation could be used to produce not only analgesia but also improved memory and concentration. Systems originally used in medicine and psycho-therapy were applied to education, in particular to…

  13. Advanced Space Fission Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Borowski, Stanley K.

    2010-01-01

    Fission has been considered for in-space propulsion since the 1940s. Nuclear Thermal Propulsion (NTP) systems underwent extensive development from 1955-1973, completing 20 full power ground tests and achieving specific impulses nearly twice that of the best chemical propulsion systems. Space fission power systems (which may eventually enable Nuclear Electric Propulsion) have been flown in space by both the United States and the Former Soviet Union. Fission is the most developed and understood of the nuclear propulsion options (e.g. fission, fusion, antimatter, etc.), and fission has enjoyed tremendous terrestrial success for nearly 7 decades. Current space nuclear research and technology efforts are focused on devising and developing first generation systems that are safe, reliable and affordable. For propulsion, the focus is on nuclear thermal rockets that build on technologies and systems developed and tested under the Rover/NERVA and related programs from the Apollo era. NTP Affordability is achieved through use of previously developed fuels and materials, modern analytical techniques and test strategies, and development of a small engine for ground and flight technology demonstration. Initial NTP systems will be capable of achieving an Isp of 900 s at a relatively high thrust-to-weight ratio. The development and use of first generation space fission power and propulsion systems will provide new, game changing capabilities for NASA. In addition, development and use of these systems will provide the foundation for developing extremely advanced power and propulsion systems capable of routinely and affordably accessing any point in the solar system. The energy density of fissile fuel (8 x 10(exp 13) Joules/kg) is more than adequate for enabling extensive exploration and utilization of the solar system. For space fission propulsion systems, the key is converting the virtually unlimited energy of fission into thrust at the desired specific impulse and thrust

  14. Robust entanglement between a movable mirror and atomic ensemble and entanglement transfer in coupled optomechanical system

    NASA Astrophysics Data System (ADS)

    Bai, Cheng-Hua; Wang, Dong-Yang; Wang, Hong-Fu; Zhu, Ai-Dong; Zhang, Shou

    2016-09-01

    We propose a scheme for the creation of robust entanglement between a movable mirror and atomic ensemble at the macroscopic level in coupled optomechanical system. We numerically simulate the degree of entanglement of the bipartite macroscopic entanglement and show that it depends on the coupling strength between the cavities and is robust with respect to the certain environment temperature. Inspiringly and surprisingly, according to the reported relation between the mechanical damping rate and the mechanical frequency of the movable mirror, the numerical simulation result shows that such bipartite macroscopic entanglement persists for environment temperature up to 170 K, which breaks the liquid nitrogen cooling and liquid helium cooling and largely lowers down the experiment cost. We also investigate the entanglement transfer based on this coupled system. The scheme can be used for the realization of quantum memories for continuous variable quantum information processing and quantum-limited displacement measurements.

  15. Robust entanglement between a movable mirror and atomic ensemble and entanglement transfer in coupled optomechanical system.

    PubMed

    Bai, Cheng-Hua; Wang, Dong-Yang; Wang, Hong-Fu; Zhu, Ai-Dong; Zhang, Shou

    2016-09-14

    We propose a scheme for the creation of robust entanglement between a movable mirror and atomic ensemble at the macroscopic level in coupled optomechanical system. We numerically simulate the degree of entanglement of the bipartite macroscopic entanglement and show that it depends on the coupling strength between the cavities and is robust with respect to the certain environment temperature. Inspiringly and surprisingly, according to the reported relation between the mechanical damping rate and the mechanical frequency of the movable mirror, the numerical simulation result shows that such bipartite macroscopic entanglement persists for environment temperature up to 170 K, which breaks the liquid nitrogen cooling and liquid helium cooling and largely lowers down the experiment cost. We also investigate the entanglement transfer based on this coupled system. The scheme can be used for the realization of quantum memories for continuous variable quantum information processing and quantum-limited displacement measurements.

  16. Robust entanglement between a movable mirror and atomic ensemble and entanglement transfer in coupled optomechanical system.

    PubMed

    Bai, Cheng-Hua; Wang, Dong-Yang; Wang, Hong-Fu; Zhu, Ai-Dong; Zhang, Shou

    2016-01-01

    We propose a scheme for the creation of robust entanglement between a movable mirror and atomic ensemble at the macroscopic level in coupled optomechanical system. We numerically simulate the degree of entanglement of the bipartite macroscopic entanglement and show that it depends on the coupling strength between the cavities and is robust with respect to the certain environment temperature. Inspiringly and surprisingly, according to the reported relation between the mechanical damping rate and the mechanical frequency of the movable mirror, the numerical simulation result shows that such bipartite macroscopic entanglement persists for environment temperature up to 170 K, which breaks the liquid nitrogen cooling and liquid helium cooling and largely lowers down the experiment cost. We also investigate the entanglement transfer based on this coupled system. The scheme can be used for the realization of quantum memories for continuous variable quantum information processing and quantum-limited displacement measurements. PMID:27624534

  17. Evolution of mirror systems: a simple mechanism for complex cognitive functions.

    PubMed

    Bonini, Luca; Ferrari, Pier Francesco

    2011-04-01

    Mirror neurons (MNs) were first discovered in monkeys and subsequently in humans and birds. While MNs are deemed to play a number of high-level cognitive functions, here we propose that they serve a unitary form of sensorimotor recognition of others' behavior. We caution that this basic function should not be confounded with the higher order functions that stem from the wider cortical systems in which MNs are embedded. Depending on the species, MNs function at different levels of motor event recognition, from motor goals to fine grained movements, thus contributing to social learning and imitative phenomena. Recent studies show that MNs coding has a prospective nature, suggesting that MNs also play a role in anticipating and predicting the behavior of others during social interactions. The presence of mirroring mechanisms in subcortical structures related to visceromotor reactions and the large diffusion of imitative phenomena among animals suggest that MN systems may be more ancient and widespread than previously thought.

  18. Robust entanglement between a movable mirror and atomic ensemble and entanglement transfer in coupled optomechanical system

    PubMed Central

    Bai, Cheng-Hua; Wang, Dong-Yang; Wang, Hong-Fu; Zhu, Ai-Dong; Zhang, Shou

    2016-01-01

    We propose a scheme for the creation of robust entanglement between a movable mirror and atomic ensemble at the macroscopic level in coupled optomechanical system. We numerically simulate the degree of entanglement of the bipartite macroscopic entanglement and show that it depends on the coupling strength between the cavities and is robust with respect to the certain environment temperature. Inspiringly and surprisingly, according to the reported relation between the mechanical damping rate and the mechanical frequency of the movable mirror, the numerical simulation result shows that such bipartite macroscopic entanglement persists for environment temperature up to 170 K, which breaks the liquid nitrogen cooling and liquid helium cooling and largely lowers down the experiment cost. We also investigate the entanglement transfer based on this coupled system. The scheme can be used for the realization of quantum memories for continuous variable quantum information processing and quantum-limited displacement measurements. PMID:27624534

  19. Improvement in QEPAS system based on miniaturized collimator and flat mirror

    NASA Astrophysics Data System (ADS)

    Wang, Fupeng; Chang, Jun; Wang, Qiang; Liu, Yuanyuan; Liu, Zhaojun; Qin, Zengguang; Zhu, Cunguang

    2016-12-01

    An improved QEPAS (quartz enhanced photo-acoustic spectroscopy) system based on an optical structure comprising miniaturized collimator and flat mirror is proposed. The beam diameter of the miniaturized collimator is designed less than 0.2 mm in a 20 mm working distance. Experiments are set up to compare the beam quality and photo-acoustic performance of three optical structures (this one, fiber lead mode and conventional focus mode). By virtue of the micro-resonator tubes and flat mirror, the new proposed structure achieves a SNR of 260 for a 3000 ppmv water vapor sample, which is much better than 183 for the fiber lead mode and 193 for the conventional focus mode respectively. This test is achieved by using the same self-designed circuit with the same parameters. The proposed optical structure is simpler and easier for optical alignment, and provides an alternative way in improving and simplifying the QEPAS system for industrial applications.

  20. Design, test, and evaluation of an electrostatically figured membrane mirror

    NASA Astrophysics Data System (ADS)

    Moore, James D., Jr.; Patrick, Brian; Gierow, Paul A.; Troy, Edward

    2004-02-01

    Significant advances have been achieved in manufacturing optical quality membrane materials with surface quality suitable for use as first surface mirrors. These materials have been used to fabricate test articles demonstrating diffraction limited performance in the laboratory environment. These mirrors are supported using heavy rigid fixtures and pressure forces to tension the membrane. A lighter weight system is required to transition the membrane mirror technology to space hardware applications. Using electrostatic forces to tension and figure the membrane is one promising approach to developing a flight weight membrane mirror system. This paper discusses the design and testing of an experimental membrane mirror system that was developed to evaluate the potential areal density, figure accuracy and stability of a lightweight electrostatically figured mirror manufactured from precision cast optical quality membrane material.

  1. Gas fired Advanced Turbine System

    SciTech Connect

    LeCren, R.T.; White, D.J.

    1993-01-01

    The primary objective of the first phase of the Advanced Gas Turbine System (ATS) program was the concept definition of an advanced engine system that meets efficiency and emission goals far exceeding those that can be provided with today`s equipment. The thermal efficiency goal for such an advanced industrial engine was set at 50% some 15 percentage points higher than current equipment levels. Exhaust emissions goals for oxides of nitrogen (NO{sub x}), carbon monoxide (CO), and unburned hydrocarbons (UH) were fixed at 8 parts per million by volume (ppmv), 20 ppmv, and 20 ppmv respectively, corrected to 15% oxygen (O{sub 2}) levels. Other goals had to be addressed; these involved reducing the cost of power produced by 10 percent and improving or maintaining the reliability, availability, and maintainability (RAM) at current levels. This advanced gas turbine was to be fueled with natural gas, and it had to embody features that would allow it bum coal or coal derived fuels.

  2. Focus control system for stretched-membrane mirror module

    DOEpatents

    Butler, Barry L.; Beninga, Kelly J.

    1991-01-01

    A focus control system dynamically sets and controls the focal length of a reflective membrane supported between a perimeter frame. A rear membrane is also supported between the perimeter frame rearward and spaced apart from a back side of the reflective membrane. The space between the membranes defines a plenum space into which a mass of gas at a first pressure is inserted. The pressure differential between the first pressure and an external pressure, such as the atmospheric pressure, causes the reflective membrane to assume a first curvature relative to a reference plane associated with the perimeter frame. This curvature defines the focal length of the reflective membrane. The focal length is dynamically controlled by changing the volume of the plenum space, thereby changing the first pressure. The system can be used to change or maintain the pressure differential and hence the front membrane curvature. The plenum volume is changed by pushing or pulling on a central section of the rear membrane using a suitable actuator. Sensing means continuously sense the location of the reflective membrane relative to the reference plane. This sensed position is compared to a reference position, and a resulting error signal, comprising the difference between the sensed position and reference position, drives the actuator in a direction to minimize the difference. A vent value compensates for temperature changes or leaks in the closed volume by allowing the pressure differential to be adjusted as required to center the working range of the actuator about the desired focal length.

  3. Focus control system for stretched-membrane mirror module

    DOEpatents

    Butler, B.L.; Beninga, K.J.

    1991-05-21

    A focus control system dynamically sets and controls the focal length of a reflective membrane supported between a perimeter frame. A rear membrane is also supported between the perimeter frame rearward and spaced apart from a back side of the reflective membrane. The space between the membranes defines a plenum space into which a mass of gas at a first pressure is inserted. The pressure differential between the first pressure and an external pressure, such as the atmospheric pressure, causes the reflective membrane to assume a first curvature relative to a reference plane associated with the perimeter frame. This curvature defines the focal length of the reflective membrane. The focal length is dynamically controlled by changing the volume of the plenum space, thereby changing the first pressure. The system can be used to change or maintain the pressure differential and hence the front membrane curvature. The plenum volume is changed by pushing or pulling on a central section of the rear membrane using a suitable actuator. Sensing means continuously sense the location of the reflective membrane relative to the reference plane. This sensed position is compared to a reference position, and a resulting error signal, comprising the difference between the sensed position and reference position, drives the actuator in a direction to minimize the difference. A vent value compensates for temperature changes or leaks in the closed volume by allowing the pressure differential to be adjusted as required to center the working range of the actuator about the desired focal length. 13 figures.

  4. Optical design of 400-1000nm spectral imaging system based on a single freeform mirror

    NASA Astrophysics Data System (ADS)

    Hou, Jia; He, Zhiping; Shu, Rong

    2015-10-01

    The imaging spectrometer supplies spectral images in one spectral dimension and two spatial dimensions simultaneously. The Offner spectral imaging system was outstanding because of its small volume, light weight, free spectral smile and little keystone. However, the manufacture of the convex grating is a challenge and the cost is high. Here, an optical design of a compact 400-1000nm spectral imaging system using a planar grating based on a single freeform mirror was proposed. The spectrograph was similar with the Offner structure, only the grating is planar. The multi-spectra was split by the planar diffraction grating, and the collimating mirror and the focusing mirror were the same freeform surface by using it twice. The freeform surface was non-rotational symmetry. Its large degree of freedom can correct kinds of aberration, such as astigmatism, smile and keystone. The system has a compact volume as 120×100×100mm3. The entrance slit was 6mm, and the object NA(numerical aperture) was 0.12. The pixel size of the detector was 16μm×16μm, and its resolution was 375(spatial)×400(spectral). The design result showed that image quality close to the diffraction limit has been obtained. The maximums of the keystone and the smile at all working wavelengths in all fields were respectively 1.6μm and 7.5μm, which were both less than half of the pixel size. At last, the tolerance analysis considering manufacture and alignment of the system was done, the result showed that the manufacturability of the existing diamond turning machining technology can satisfy the accuracy need of the freeform mirror.

  5. Design and fabrication of multimode interference couplers based on digital micro-mirror system

    NASA Astrophysics Data System (ADS)

    Wu, Sumei; He, Xingdao; Shen, Chenbo

    2008-03-01

    Multimode interference (MMI) couplers, based on the self-imaging effect (SIE), are accepted popularly in integrated optics. According to the importance of MMI devices, in this paper, we present a novel method to design and fabricate MMI couplers. A technology of maskless lithography to make MMI couplers based on a smart digital micro-mirror device (DMD) system is proposed. A 1×4 MMI device is designed as an example, which shows the present method is efficient and cost-effective.

  6. Advanced flight control system study

    NASA Technical Reports Server (NTRS)

    Hartmann, G. L.; Wall, J. E., Jr.; Rang, E. R.; Lee, H. P.; Schulte, R. W.; Ng, W. K.

    1982-01-01

    A fly by wire flight control system architecture designed for high reliability includes spare sensor and computer elements to permit safe dispatch with failed elements, thereby reducing unscheduled maintenance. A methodology capable of demonstrating that the architecture does achieve the predicted performance characteristics consists of a hierarchy of activities ranging from analytical calculations of system reliability and formal methods of software verification to iron bird testing followed by flight evaluation. Interfacing this architecture to the Lockheed S-3A aircraft for flight test is discussed. This testbed vehicle can be expanded to support flight experiments in advanced aerodynamics, electromechanical actuators, secondary power systems, flight management, new displays, and air traffic control concepts.

  7. Analysis of FEL optical systems with grazing incidence mirrors

    SciTech Connect

    Knapp, C.E.; Viswanathan, V.K.; Bender, S.C.; Appert, Q.D.; Lawrence, G.; Barnard, C.

    1986-01-01

    The use of grazing incidence optics in resonators alleviates the problem of damage to the optical elements and permits higher powers in cavities of reasonable dimensions for a free electron laser (FEL). The design and manufacture of a grazing incidence beam expander for the Los Alamos FEL mock-up has been completed. In this paper, we describe the analysis of a bare cavity, grazing incidence optical beam expander for an FEL system. Since the existing geometrical and physical optics codes were inadequate for such an analysis, the GLAD code was modified to include global coordinates, exact conic representation, raytracing, and exact aberration features to determine the alignment sensitivities of laser resonators. A resonator cavity has been manufactured and experimentally setup in the Optical Evaluation Laboratory at Los Alamos. Calculated performance is compared with the laboratory measurements obtained so far.

  8. Joint-transform correlator systems using deformable-mirror spatial light modulators

    NASA Technical Reports Server (NTRS)

    Florence, James M.

    1989-01-01

    Two joint-transform correlator systems based on deformable-mirror-device (DMD) spatial light modulators and CCD video cameras are described. The system designs provide for real-time correlation between video-formatted input scenes and stored reference images. The DMD light modulators are used exclusively for inputting data in the optical stages of these systems, and the CCD cameras are used to provide the critical square-law detection required in joint-transform achitectures. Experimental verification of the functionality of these DMD/CCD joint-transform systems is also presented.

  9. Simulation of the fast steering mirror control system based on gyro velocity feedback

    NASA Astrophysics Data System (ADS)

    Kuang, Jiagming; Tang, Tao; Fu, Chengyu; Ding, Ke; Yu, Wei

    2009-11-01

    The fast steering mirror is a significant element of the photoelectric precision tracking system and is mainly used for attenuating the tracking error of the main axis and rejecting the line-of-sight jitter caused by various disturbances. A control loop model is constructed and object parameters have been identified according to this model in this paper. Low sampling frequency introduce great delay into the imaging tracking system, which may restrict greatly the closed-loop bandwidth, reduce tracking precision of the system and even make the system unsteady. Various elements which limit tracking loop bandwidth are presented and analyzed. Three tracking systems with different sampling frequency are simulated and analyzed. From the simulation result the conclusion can be drawn that it is difficult to increase the closedloop bandwidth in the presence of great delay by means of the general control method. Accordingly feedback control or feed forward control may be tried to improve the error attenuation of the system. The micro-mechanical gyro can be used for measuring the angular velocity of fast steering mirror, so output of velocity gyro as velocity loop feedback may improve the system performance. Furthermore, the velocity loop feedback can enhance the rigidity and the output stability of the tracking system. Finally, the velocity feedback can increase the type of the open loop system; consequently it will improve the error attenuation of the system. The simulation result shows that the tracking precision of the system with velocity feedback is 10 times better than the system without velocity feedback.

  10. Advanced gas turbine systems program

    SciTech Connect

    Zeh, C.M.

    1995-06-01

    The U.S. Department of Energy (DOE) is sponsoring a program to develop fuel-efficient gas turbine-based power systems with low emissions. DOE`s Office of Fossil Energy (DOE/FE) and Office of Energy Efficiency and Renewable Energy (DOE/EE) have initiated an 8-year program to develop high-efficiency, natural gas-fired advanced gas turbine power systems. The Advanced Turbine Systems (ATS) Program will support full-scale prototype demonstration of both industrial- and utility-scale systems that will provide commercial marketplace entries by the year 2000. When the program targets are met, power system emissions will be lower than from the best technology in use today. Efficiency of the utility-scale units will be greater than 60 percent on a lower heating value basis, and emissions of carbon dioxide will be reduced inversely with this increase. Industrial systems will also see an improvement of at least 15 percent in efficiency. Nitrogen oxides will be reduced by at least 10 percent, and carbon monoxide and hydrocarbon emissions will each be kept below 20 parts per million, for both utility and industrial systems.

  11. Sinistrad mirror writing and reading after brain concussion in a bi-systemic (oriento-occidental) polyglot.

    PubMed

    Streifler, M; Hofman, S

    1976-12-01

    The problem of mirror writing and reading is discussed in the light of a clinical case, where this disturbance appeared after an apparently minor head injury. Mirror writing and reading in this polyglot individual affected only the sinistrad (Hebrew) writing and reading system, leaving the dextrad (Latin) system unimpaired. This disturbance appeared together with dyscalculia, left-right disorientation and slight temporal confusion, suggestive of parieto-occipital lobe pathology. The clinical picture also showed apparently "conversional" traits, such as are sometimes seen in incomplete parietal lobe syndromes. The relevant literature is reviewed and patho-physiological mechanisms of mirror reversal are discussed. PMID:1009772

  12. Mirror Advanced Reactor Study (MARS). Final report. Volume 1-A. Commercial fusion electric plant

    SciTech Connect

    Donohue, M.L.; Price, M.E.

    1984-07-01

    Volume 1-A contains the following chapters: (1) plasma engineering, (2) magnets, (3) ecr heating systems, (4) anchor ion-cyclotron resonance heating system, (5) sloshing ion neutral beam, (6) end cell structure, (7) end plasma technology, (8) fueling, (9) startup ion cyclotron resonant heating systems, and (10) end cell radiation analysis. (MOW)

  13. Alignment System for Full-Shell Replicated X-Ray Mirrors

    NASA Technical Reports Server (NTRS)

    Gubarev, Mikhail; Arnold, William; Ramsey, Brian

    2009-01-01

    We are developing grazing-incidence x-ray optics for high-energy astrophysical applications using the electroformnickel replication process. For space-based applications these optics must be light-weight yet stable, which dictates the use of very-thin-walled full-shell mirrors. Such shells have been fabricated with resolution as good as 11 arcsec for hard x-rays, and technology enhancements under development at MSFC are aimed at producing mirrors with resolution better than 10 arcsec. The challenge, however, is to preserve this resolution during mounting and assembly. We present here a status report on a mounting and alignment system currently under development at Marshall Space Flight Center designed to meet this challenge.

  14. Do infants provide evidence that the mirror system is involved in action understanding?

    PubMed

    Southgate, Victoria

    2013-09-01

    The mirror neuron theory of action understanding makes predictions concerning how the limited motor repertoire of young infants should impact on their ability to interpret others' actions. In line with this theory, an increasing body of research has identified a correlation between infants' abilities to perform an action, and their ability to interpret that action as goal-directed when performed by others. In this paper, I will argue that the infant data does by no means unequivocally support the mirror neuron theory of action understanding and that alternative interpretations of the data should be considered. Furthermore, some of this data can be better interpreted in terms of an alternative view, which holds that the role of the motor system in action perception is more likely to be one of enabling the observer to predict, after a goal has been identified, how that goal will be attained.

  15. Research on advanced transportation systems

    NASA Astrophysics Data System (ADS)

    Nagai, Hirokazu; Hashimoto, Ryouhei; Nosaka, Masataka; Koyari, Yukio; Yamada, Yoshio; Noda, Keiichirou; Shinohara, Suetsugu; Itou, Tetsuichi; Etou, Takao; Kaneko, Yutaka

    1992-08-01

    An overview of the researches on advanced space transportation systems is presented. Conceptual study is conducted on fly back boosters with expendable upper stage rocket systems assuming a launch capacity of 30 tons and returning to the launch site by the boosters, and prospect of their feasibility is obtained. Reviews are conducted on subjects as follows: (1) trial production of 10 tons sub scale engines for the purpose of acquiring hardware data and picking up technical problems for full scale 100 tons thrust engines using hydrocarbon fuels; (2) development techniques for advanced liquid propulsion systems from the aspects of development schedule, cost; (3) review of conventional technologies, and common use of component; (4) oxidant switching propulsion systems focusing on feasibility of Liquefied Air Cycle Engine (LACE) and Compressed Air Cycle Engine (CACE); (5) present status of slosh hydrogen manufacturing, storage, and handling; (6) construction of small high speed dynamometer for promoting research on mini pump development; (7) hybrid solid boosters under research all over the world as low-cost and clean propulsion systems; and (8) high performance solid propellant for upper stage and lower stage propulsion systems.

  16. Design of the primary mirror segment support system for the E-ELT

    NASA Astrophysics Data System (ADS)

    Cavaller, Lluis; Marrero, Juan; Castro, Javier; Morante, Esteban; Ronquillo, Mariano; Hernández, Elvio

    2008-07-01

    The European Extremely Large Telescope (E-ELT) is a 42-m class optical telescope with a segmented primary mirror composed of 984 segments which is currently being studied by ESO (European Southern Observatory). The segment support system combines a series of mechanical whiffletrees for the axial support, a central diaphragm for lateral support and a torsional constrainer. These elements are fixed to a common moving frame which is actively moved by means of three actuators in piston and tip-tilt in order to keep the whole primary mirror in phase. The moving frame is fixed to the segments subcells, which properly attach the segments to the cell structure, by means of special flexures, allowing large axial alignment capability combined with high lateral stiffness. This paper describes the development of the support system for the primary mirror segments of the E-ELT, which has been specified for a high stiffness and eigenfrequencies, 60Hz for axial modes and 40Hz for lateral ones.

  17. Progress report towards a digital mirror device based confocal microscopic system

    NASA Astrophysics Data System (ADS)

    Yi, Dingrong; Lin, Shunhua; Huang, Simian; Xie, Shaochuan

    2013-12-01

    It is widely believed that by using a digital mirror device (DMD) as the spatial light modulator (SLM) of a programmable array microcopy (PAM), it is possible to achieve a cost-effective alternative to expensive confocal imaging devices. During the past decade, the design of such a DMD based PAM instrument has been frequently reported to enhance resolution and contrast, convincing images with improved quality are rare to be seen. The concrete implementation of a DMD based PAM instrument needs to successfully resolve multiple issues such as the adverse effects caused by the tilt angle of the micro-mirrors from the base board, the registration between a micro mirror of the DMD and the image pixel of the photo-detector and so on. In this paper, we report the design of a middle body consisting of a DMD as an independent attachment to a conventional microscope to convert the latter into a confocal imaging system, in a similar way as a filter turret that is placed below the head and the objectives of a regular microscopy to convert it into a fluorescent microscopy. Images of real objects with improved contrast are provided to demonstrate the effectiveness of using a DMD as SLM to improve the contrast of a PAM instrument. Such a PAM instrument has many advantages compared to conventional laser-scanning confocal systems including lower costs and higher imaging speeds. In addition, it allows convenient dynamic adjustments between imaging quality and imaging speed.

  18. Design of an interferometric system for piston measurements in segmented primary mirrors

    NASA Astrophysics Data System (ADS)

    Arasa, Josep; Laguarta, Ferran; Pizarro, Carlos; Tomas, Nuria; Pinto, Agusti

    2000-10-01

    Recently, telescopes with segmented primary mirrors are becoming increasingly popular due to their ability of achieving large apertures without the inconveniences caused by the fabrication and handling of monolithic surfaces with 8m (or over) in diameter. The difference in position of each pair of adjacent segments along the local normal of their interface (called piston hereafter), however, needs to be precisely measured in order to provide a diffraction- limited image. If a system yielding the nanometric accuracy required in piston measurements worked in daylight hours, the resultant saving in observation time would be an important advance on a majority of the state-of-the-art piston measurement systems. An interferometric piston measurement instrument accomplishing such objectives has been designed starting from the usual Michelson configuration at the CD6 (Terrassa, Spain), and its final test has been carried out in the test workbench of the Instituto de Astrofisica de Canarias (IAC, Canary Islands, Spain). Its optical layout relies on projecting the reference arm of the interferometer onto one of the segments of the pair considered, along the direction of the local normal to the surface while the measurement arm is projected onto the interface which divides the pair of segments considered. The field of view and its illumination are calculated to be equivalent in both segments. The lateral shift of the fringes in both interferograms determines the piston error present. A combination of monochromatic and white light is used, in order to remove the (lambda) /2 phase ambiguities present in piston measurements without losing the required resolution in the measurement. In this paper, the optical design of this interferometric piston measurement instrument will be presented. The particular configuration used in the interferometer, the implementation of an imaging system allowing to see both the interface of the segments and the interference fringes, the effect of the

  19. Enhanced visible and near-infrared capabilities of the JET mirror-linked divertor spectroscopy system

    SciTech Connect

    Lomanowski, B. A. Sharples, R. M.; Meigs, A. G.; Conway, N. J.; Zastrow, K.-D.; Heesterman, P.; Kinna, D. [EURATOM Collaboration: JET-EFDA Team

    2014-11-15

    The mirror-linked divertor spectroscopy diagnostic on JET has been upgraded with a new visible and near-infrared grating and filtered spectroscopy system. New capabilities include extended near-infrared coverage up to 1875 nm, capturing the hydrogen Paschen series, as well as a 2 kHz frame rate filtered imaging camera system for fast measurements of impurity (Be II) and deuterium Dα, Dβ, Dγ line emission in the outer divertor. The expanded system provides unique capabilities for studying spatially resolved divertor plasma dynamics at near-ELM resolved timescales as well as a test bed for feasibility assessment of near-infrared spectroscopy.

  20. Mirror monochromator

    SciTech Connect

    Mankos, Marian; Shadman, Khashayar

    2014-12-02

    energy of 80-120 keV). Specialized software packages that have been developed by MEBS, Ltd. were used to calculate the electron optical properties of the key monochromator components: namely, the magnetic prism, the electron mirror, and the electron lenses. In the final step, these results were folded into a model describing the key electron-optical parameters of the complete monochromator. The simulations reveal that the mirror monochromator can reduce the energy spread of a Schottky electron source, an established electron emitter used widely in EMs, to 10 meV for practical beam current values and that further reduction of the energy spread down to 3 meV is possible for low current applications with a Cold Field Emitter (an electron source with 10x the brightness of a Schottky source). MirrorChroms can be designed and built to attach to different types of TEMs and SEMs, thus making them suitable for enhancing the study of the structure, composition, and bonding states of new materials at the nanoscale to advance material science research in the field of nanotechnology as well as biomedical research.

  1. Six movements measurement system employed for GAIA secondary mirror positioning system vacuum tests at cryogenic temperatures

    NASA Astrophysics Data System (ADS)

    Ramos Zapata, Gonzalo; Sánchez Rodríguez, Antonio; Garranzo García-Ibarrola, Daniel; Belenguer Dávila, Tomás

    2008-07-01

    In this work, the optical measurement system employed to evaluate the performance of a 6 degrees of freedom (dof) positioning mechanism under cryogenic conditions is explored. The mechanism, the flight model of three translations and three rotations positioning mechanism, was developed by the Spanish company SENER (for ASTRIUM) to fulfil the high performance requirements from ESA technology preparatory program for the positioning of a secondary mirror within the GAIA Astrometric Mission. Its performance has been evaluated under vacuum and temperature controlled conditions (up to a 10-6mbar and 100K) at the facilities of the Space Instrumentation Laboratory (LINES) of the Aerospace Technical Nacional Institute of Spain (INTA). After the description of the 'alignment tool' developed to compare a fixed reference with the optical signal corresponding to the movement under evaluation, the optical system that allows measuring the displacements and the rotations in the three space directions is reported on. Two similar bread-boards were defined and mounted for the measurements purpose, one containing two distancemeters, in order to measure the displacements through the corresponding axis, and an autocollimator in order to obtain the rotations on the plane whose normal vector is the axis mentioned before, and other one containing one distancemeter and one autocollimator. Both distancemeter and autocollimator measurements have been combined in order to extract the information about the accuracy of the mechanism movements as well as their repeatability under adverse environmental conditions.

  2. Mirror system activity for action and language is embedded in the integration of dorsal and ventral pathways.

    PubMed

    Arbib, Michael A

    2010-01-01

    We develop the view that the involvement of mirror neurons in embodied experience grounds brain structures that underlie language, but that many other brain regions are involved. We stress the cooperation between the dorsal and ventral streams in praxis and language. Both have perceptual and motor schemas but the perceptual schemas in the dorsal path are affordances linked to specific motor schemas for detailed motor control, whereas the ventral path supports planning and decision making. This frames the hypothesis that the mirror system for words evolved from the mirror system for actions to support words-as-phonological-actions, with semantics provided by the linkage to neural systems supporting perceptual and motor schemas. We stress the importance of computational models which can be linked to the parametric analysis of data and conceptual analysis of these models to support new patterns of understanding of the data. In the domain of praxis, we assess the FARS model of the canonical system for grasping, the MNS models for the mirror system for grasping, and the Augmented Competitive Queuing model that extends the control of action to the opportunistic scheduling of action sequences and also offers a new hypothesis on the role of mirror neurons in self action. Turning to language, we use Construction Grammar as our linguistic framework to get beyond single words to phrases and sentences, and initiate analysis of what brain functions must complement mirror systems to support this functionality. PMID:19942271

  3. Optimization design about gimbal structure of high-precision autonomous celestial navigation tracking mirror system

    NASA Astrophysics Data System (ADS)

    Huang, Wei; Yang, Xiao-xu; Han, Jun-feng; Wei, Yu; Zhang, Jing; Xie, Mei-lin; Yue, Peng

    2016-01-01

    High precision tracking platform of celestial navigation with control mirror servo structure form, to solve the disadvantages of big volume and rotational inertia, slow response speed, and so on. It improved the stability and tracking accuracy of platform. Due to optical sensor and mirror are installed on the middle-gimbal, stiffness and resonant frequency requirement for high. Based on the application of finite element modality analysis theory, doing Research on dynamic characteristics of the middle-gimbal, and ANSYS was used for the finite element dynamic emulator analysis. According to the result of the computer to find out the weak links of the structure, and Put forward improvement suggestions and reanalysis. The lowest resonant frequency of optimization middle-gimbal avoid the bandwidth of the platform servo mechanism, and much higher than the disturbance frequency of carrier aircraft, and reduces mechanical resonance of the framework. Reaching provides a theoretical basis for the whole machine structure optimization design of high-precision of autonomous Celestial navigation tracking mirror system.

  4. Endoscopic optical coherence tomography with a modified microelectromechanical systems mirror for detection of bladder cancers

    NASA Astrophysics Data System (ADS)

    Xie, Tuqiang; Xie, Huikai; Fedder, Gary K.; Pan, Yingtian

    2003-11-01

    Experimental results of a modified micromachined microelectromechanical systems (MEMS) mirror for substantial enhancement of the transverse laser scanning performance of endoscopic optical coherence tomography (EOCT) are presented. Image distortion due to buckling of MEMS mirror in our previous designs was analyzed and found to be attributed to excessive internal stress of the transverse bimorph meshes. The modified MEMS mirror completely eliminates bimorph stress and the resultant buckling effect, which increases the wobbling-free angular optical actuation to greater than 37°, exceeding the transverse laser scanning requirements for EOCT and confocal endoscopy. The new optical coherence tomography (OCT) endoscope allows for two-dimensional cross-sectional imaging that covers an area of 4.2 mm × 2.8 mm (limited by scope size) and at roughly 5 frames/s instead of the previous area size of 2.9 mm × 2.8 mm and is highly suitable for noninvasive and high-resolution imaging diagnosis of epithelial lesions in vivo. EOCT images of normal rat bladders and rat bladder cancers are compared with the same cross sections acquired with conventional bench-top OCT. The results clearly demonstrate the potential of EOCT for in vivo imaging diagnosis and precise guidance for excisional biopsy of early bladder cancers.

  5. Mirror Advanced Reactor Study (MARS). Final report. Volume 2. Commercial fusion synfuels plant

    SciTech Connect

    Donohue, M.L.; Price, M.E.

    1984-07-01

    Volume 2 contains the following chapters: (1) synfuels; (2) physics base and parameters for TMR; (3) high-temperature two-temperature-zone blanket system for synfuel application; (4) thermochemical hydrogen processes; (5) interfacing the sulfur-iodine cycle; (6) interfacing the reactor with the thermochemical process; (7) tritium control in the blanket system; (8) the sulfur trioxide fluidized-bed composer; (9) preliminary cost estimates; and (10) fuels beyond hydrogen. (MOW)

  6. Water Cooled Mirror Design

    SciTech Connect

    Dale, Gregory E.; Holloway, Michael Andrew; Pulliam, Elias Noel

    2015-03-30

    This design is intended to replace the current mirror setup being used for the NorthStar Moly 99 project in order to monitor the target coupon. The existing setup has limited movement for camera alignment and is difficult to align properly. This proposed conceptual design for a water cooled mirror will allow for greater thermal transfer between the mirror and the water block. It will also improve positioning of the mirror by using flexible vacuum hosing and a ball head joint capable of a wide range of motion. Incorporating this design into the target monitoring system will provide more efficient cooling of the mirror which will improve the amount of diffraction caused by the heating of the mirror. The process of aligning the mirror for accurate position will be greatly improved by increasing the range of motion by offering six degrees of freedom.

  7. Virtual Mirrors

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    2010-01-01

    The multiple-reflection photograph in Fig. 1 was taken in an elevator on board the cruise ship Norwegian Jade in March 2008. Three of the four walls of the elevator were mirrored, allowing me to see the combination of two standard arrangements of plane mirrors: two mirrors set at 90 degrees to each other and two parallel mirrors. Optical phenomena…

  8. NASA Advanced Explorations Systems: Advancements in Life Support Systems

    NASA Technical Reports Server (NTRS)

    Shull, Sarah A.; Schneider, Walter F.

    2016-01-01

    The NASA Advanced Exploration Systems (AES) Life Support Systems (LSS) project strives to develop reliable, energy-efficient, and low-mass spacecraft systems to provide environmental control and life support systems (ECLSS) critical to enabling long duration human missions beyond low Earth orbit (LEO). Highly reliable, closed-loop life support systems are among the capabilities required for the longer duration human space exploration missions assessed by NASA's Habitability Architecture Team (HAT). The LSS project is focused on four areas: architecture and systems engineering for life support systems, environmental monitoring, air revitalization, and wastewater processing and water management. Starting with the international space station (ISS) LSS systems as a point of departure (where applicable), the mission of the LSS project is three-fold: 1. Address discrete LSS technology gaps 2. Improve the reliability of LSS systems 3. Advance LSS systems towards integrated testing on the ISS. This paper summarized the work being done in the four areas listed above to meet these objectives. Details will be given on the following focus areas: Systems Engineering and Architecture- With so many complex systems comprising life support in space, it is important to understand the overall system requirements to define life support system architectures for different space mission classes, ensure that all the components integrate well together and verify that testing is as representative of destination environments as possible. Environmental Monitoring- In an enclosed spacecraft that is constantly operating complex machinery for its own basic functionality as well as science experiments and technology demonstrations, it's possible for the environment to become compromised. While current environmental monitors aboard the ISS will alert crew members and mission control if there is an emergency, long-duration environmental monitoring cannot be done in-orbit as current methodologies

  9. Advanced glycation end product associated skin autofluorescence: a mirror of vascular function?

    PubMed

    Hofmann, Britt; Adam, Anne-Catrin; Jacobs, Kathleen; Riemer, Marcus; Erbs, Christian; Bushnaq, Hasan; Simm, Andreas; Silber, Rolf-Edgar; Santos, Alexander Navarrete

    2013-01-01

    Advanced glycation end products (AGEs) seem to be involved in aging as well as in the development of cardiovascular diseases. During aging, AGEs accumulate in extracellular matrix proteins like collagen and contribute to vessel stiffness. Whether non-invasive measurement of AGE accumulation in the skin may reflect vessel function and vessel protein modification is unknown. Herein we set out to analyze the AGE-modifications in the collagens extracted from residual bypass graft material, the skin autofluorescence reflecting the accumulation of AGEs in the body as well as the pulse wave velocity reflecting vessel stiffness. Collagen types I and III (pepsin digestible collagen fraction) were isolated from the veins of 52 patients by proteolysis. The residual collagen fraction was further extracted by collagenase digestion. Collagen was quantified by hydroxyproline assay and AGEs by the AGE intrinsic fluorescence. Skin autofluorescence was measured with an autofluorescence reader; pulse wave velocity with the VICORDER. The collagen AGE autofluorescence in patient vein graft material increased with patient age. The pepsin digestible collagen fraction was significantly less modified in comparison to the collagenase digestible fraction. Decreasing amounts of extracted collagenase digestible collagen correspond with increasing AGE autofluorescence. Skin autofluorescence and vessel stiffness were significantly linked to the AGE autofluorescence of the collagenase digestible collagen fraction from graft material. In conclusion we have found that skin autofluorescence and pulse wave velocity as non-invasive parameters significantly correlate with the AGE contained in graft material and therefore are strong predictors of vessel AGE modifications in patients with coronary heart disease. Whether the analysis of the skin autofluorescence leads to an improvement of the risk stratification in patients suffering from cardiovascular disease has to be further tested.

  10. Advanced glycation end product associated skin autofluorescence: a mirror of vascular function?

    PubMed

    Hofmann, Britt; Adam, Anne-Catrin; Jacobs, Kathleen; Riemer, Marcus; Erbs, Christian; Bushnaq, Hasan; Simm, Andreas; Silber, Rolf-Edgar; Santos, Alexander Navarrete

    2013-01-01

    Advanced glycation end products (AGEs) seem to be involved in aging as well as in the development of cardiovascular diseases. During aging, AGEs accumulate in extracellular matrix proteins like collagen and contribute to vessel stiffness. Whether non-invasive measurement of AGE accumulation in the skin may reflect vessel function and vessel protein modification is unknown. Herein we set out to analyze the AGE-modifications in the collagens extracted from residual bypass graft material, the skin autofluorescence reflecting the accumulation of AGEs in the body as well as the pulse wave velocity reflecting vessel stiffness. Collagen types I and III (pepsin digestible collagen fraction) were isolated from the veins of 52 patients by proteolysis. The residual collagen fraction was further extracted by collagenase digestion. Collagen was quantified by hydroxyproline assay and AGEs by the AGE intrinsic fluorescence. Skin autofluorescence was measured with an autofluorescence reader; pulse wave velocity with the VICORDER. The collagen AGE autofluorescence in patient vein graft material increased with patient age. The pepsin digestible collagen fraction was significantly less modified in comparison to the collagenase digestible fraction. Decreasing amounts of extracted collagenase digestible collagen correspond with increasing AGE autofluorescence. Skin autofluorescence and vessel stiffness were significantly linked to the AGE autofluorescence of the collagenase digestible collagen fraction from graft material. In conclusion we have found that skin autofluorescence and pulse wave velocity as non-invasive parameters significantly correlate with the AGE contained in graft material and therefore are strong predictors of vessel AGE modifications in patients with coronary heart disease. Whether the analysis of the skin autofluorescence leads to an improvement of the risk stratification in patients suffering from cardiovascular disease has to be further tested. PMID:22588061

  11. Demonstration Advanced Avionics System (DAAS), Phase 1

    NASA Technical Reports Server (NTRS)

    Bailey, A. J.; Bailey, D. G.; Gaabo, R. J.; Lahn, T. G.; Larson, J. C.; Peterson, E. M.; Schuck, J. W.; Rodgers, D. L.; Wroblewski, K. A.

    1981-01-01

    Demonstration advanced anionics system (DAAS) function description, hardware description, operational evaluation, and failure mode and effects analysis (FMEA) are provided. Projected advanced avionics system (PAAS) description, reliability analysis, cost analysis, maintainability analysis, and modularity analysis are discussed.

  12. A USPL functional system with articulated mirror arm for in-vivo applications in dentistry

    NASA Astrophysics Data System (ADS)

    Schelle, Florian; Meister, Jörg; Dehn, Claudia; Oehme, Bernd; Bourauel, Christoph; Frentzen, Mathias

    Ultra-short pulsed laser (USPL) systems for dental application have overcome many of their initial disadvantages. However, a problem that has not yet been addressed and solved is the beam delivery into the oral cavity. The functional system that is introduced in this study includes an articulated mirror arm, a scanning system as well as a handpiece, allowing for freehand preparations with ultra-short laser pulses. As laser source an Nd:YVO4 laser is employed, emitting pulses with a duration of tp < 10 ps at a repetition rate of up to 500 kHz. The centre wavelength is at 1064 nm and the average output power can be tuned up to 9 W. The delivery system consists of an articulated mirror arm, to which a scanning system and a custom made handpiece are connected, including a 75 mm focussing lens. The whole functional system is compact in size and moveable. General characteristics like optical losses and ablation rate are determined and compared to results employing a fixed setup on an optical table. Furthermore classical treatment procedures like cavity preparation are being demonstrated on mammoth ivory. This study indicates that freehand preparation employing an USPL system is possible but challenging, and accompanied by a variety of side-effects. The ablation rate with fixed handpiece is about 10 mm3/min. Factors like defocussing and blinding affect treatment efficiency. Laser sources with higher average output powers might be needed in order to reach sufficient preparation speeds.

  13. Mapping the flow of information within the putative mirror neuron system during gesture observation.

    PubMed

    Schippers, Marleen B; Keysers, Christian

    2011-07-01

    The putative mirror neuron system may either function as a strict feed-forward system or as a dynamic control system. A strict feed-forward system would predict that action observation leads to a predominantly temporal→parietal→premotor flow of information in which a visual representation is transformed into motor-programs which contribute to action understanding. Instead, a dynamic feedback control system would predict that the reverse direction of information flow predominates because of a combination of inhibitory forward and excitatory inverse models. Here we test which of these conflicting predictions best matches the information flow within the putative mirror neuron system (pMNS) and between the pMNS and the rest of the brain during the observation of comparatively long naturalistic stretches of communicative gestures. We used Granger causality to test the dominant direction of influence. Our results fit the predictions of the dynamic feedback control system: we found predominantly an information flow within the pMNS from premotor to parietal and middle temporal cortices. This is more pronounced during an active guessing task than while passively reviewing the same gestures. In particular, the ventral premotor cortex sends significantly more information to other pMNS areas than it receives during active guessing than during passive observation.

  14. Development of fast steering mirror control system for plasma heating and diagnostics

    SciTech Connect

    Okada, K. Kubo, S.; Shimozuma, T.; Yoshimura, Y.; Igami, H.; Takahashi, H.; Tanaka, K.; Kobayashi, S.; Ito, S.; Mizuno, Y.; Ogasawara, S.; Nishiura, M.

    2014-11-15

    A control system for a fast steering mirror has been newly developed for the electron cyclotron heating (ECH) launchers in the large helical device. This system enables two-dimensional scan during a plasma discharge and provides a simple feedback control function. A board mounted with a field programmable gate array chip has been designed to realize feedback control of the ECH beam position to maintain higher electron temperature by ECH. The heating position is determined by a plasma diagnostic signal related to the electron temperature such as electron cyclotron emission and Thomson scattering.

  15. Development of fast steering mirror control system for plasma heating and diagnostics

    NASA Astrophysics Data System (ADS)

    Okada, K.; Nishiura, M.; Kubo, S.; Shimozuma, T.; Yoshimura, Y.; Igami, H.; Takahashi, H.; Tanaka, K.; Kobayashi, S.; Ito, S.; Mizuno, Y.; Ogasawara, S.

    2014-11-01

    A control system for a fast steering mirror has been newly developed for the electron cyclotron heating (ECH) launchers in the large helical device. This system enables two-dimensional scan during a plasma discharge and provides a simple feedback control function. A board mounted with a field programmable gate array chip has been designed to realize feedback control of the ECH beam position to maintain higher electron temperature by ECH. The heating position is determined by a plasma diagnostic signal related to the electron temperature such as electron cyclotron emission and Thomson scattering.

  16. Development of fast steering mirror control system for plasma heating and diagnostics.

    PubMed

    Okada, K; Nishiura, M; Kubo, S; Shimozuma, T; Yoshimura, Y; Igami, H; Takahashi, H; Tanaka, K; Kobayashi, S; Ito, S; Mizuno, Y; Ogasawara, S

    2014-11-01

    A control system for a fast steering mirror has been newly developed for the electron cyclotron heating (ECH) launchers in the large helical device. This system enables two-dimensional scan during a plasma discharge and provides a simple feedback control function. A board mounted with a field programmable gate array chip has been designed to realize feedback control of the ECH beam position to maintain higher electron temperature by ECH. The heating position is determined by a plasma diagnostic signal related to the electron temperature such as electron cyclotron emission and Thomson scattering.

  17. The research of filtering on images with noises of the three-mirror aperture optical system

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Wu, Quanying; Fan, Junliu; Wang, Youqing

    2014-11-01

    In order to eliminate the noise in images acquired by the sparse aperture system, the modeling and filtering of electrical and optical noise are analyzed by the case of three-mirror aperture optical system. The study shows that the median filter can be applied to remove Gauss and salt & pepper noise, meanwhile high-pass filter with Gauss function can eliminate the influence of non-uniform illuminating on imaging. The Lucy-Richardson algorithm is used to restore the image, by which the resolution is heightened.

  18. Advanced System for Process Engineering

    1992-02-01

    ASPEN (Advanced System for Process Engineering) is a state of the art process simulator and economic evaluation package which was designed for use in engineering fossil energy conversion processes. ASPEN can represent multiphase streams including solids, and handle complex substances such as coal. The system can perform steady state material and energy balances, determine equipment size and cost, and carry out preliminary economic evaluations. It is supported by a comprehensive physical property system for computationmore » of major properties such as enthalpy, entropy, free energy, molar volume, equilibrium ratio, fugacity coefficient, viscosity, thermal conductivity, and diffusion coefficient for specified phase conditions; vapor, liquid, or solid. The properties may be computed for pure components, mixtures, or components in a mixture, as appropriate. The ASPEN Input Language is oriented towards process engineers.« less

  19. Mirror Advanced Reactor Study (MARS). Final report. Volume 1-B. Commercial fusion electric plant

    SciTech Connect

    Donohue, M.L.; Price, M.E.

    1984-07-01

    Volume 1-B contains the following chapters: (1) blanket and reflector; (2) central cell shield; (3) central cell structure; (4) heat transport and energy conversion; (5) tritium systems; (6) cryogenics; (7) maintenance; (8) safety; (9) radioactivity, activation, and waste disposal; (10) instrumentation and control; (11) balance of plant; (12) plant startup and operation; (13) plant availability; (14) plant construction; and (15) economic analysis.

  20. EUV reflectance characterization of the 94/304 ? flight secondary AIA mirror at beamline 6.3.2 of the Advanced Light Source

    SciTech Connect

    Soufli, R; Spiller, E; Aquila, A L; Gullikson, E M; Windt, D L

    2006-02-22

    The AIA secondary flight mirror, previously coated at Columbia University with Mg/SiC for the 303.8 {angstrom} channel and Mo/Y for the 93.9 {angstrom} channel was characterized by means of EUV reflectance measurements at beamline 6.3.2 of the Advanced Light Source (ALS) synchrotron at LBNL on January 10, 2006. Paul Boerner (LMSAL) also participated in these measurements.

  1. Advanced Land Imager Assessment System

    NASA Technical Reports Server (NTRS)

    Chander, Gyanesh; Choate, Mike; Christopherson, Jon; Hollaren, Doug; Morfitt, Ron; Nelson, Jim; Nelson, Shar; Storey, James; Helder, Dennis; Ruggles, Tim; Kaita, Ed; Levy, Raviv; Ong, Lawrence; Markham, Brian; Schweiss, Robert

    2008-01-01

    The Advanced Land Imager Assessment System (ALIAS) supports radiometric and geometric image processing for the Advanced Land Imager (ALI) instrument onboard NASA s Earth Observing-1 (EO-1) satellite. ALIAS consists of two processing subsystems for radiometric and geometric processing of the ALI s multispectral imagery. The radiometric processing subsystem characterizes and corrects, where possible, radiometric qualities including: coherent, impulse; and random noise; signal-to-noise ratios (SNRs); detector operability; gain; bias; saturation levels; striping and banding; and the stability of detector performance. The geometric processing subsystem and analysis capabilities support sensor alignment calibrations, sensor chip assembly (SCA)-to-SCA alignments and band-to-band alignment; and perform geodetic accuracy assessments, modulation transfer function (MTF) characterizations, and image-to-image characterizations. ALIAS also characterizes and corrects band-toband registration, and performs systematic precision and terrain correction of ALI images. This system can geometrically correct, and automatically mosaic, the SCA image strips into a seamless, map-projected image. This system provides a large database, which enables bulk trending for all ALI image data and significant instrument telemetry. Bulk trending consists of two functions: Housekeeping Processing and Bulk Radiometric Processing. The Housekeeping function pulls telemetry and temperature information from the instrument housekeeping files and writes this information to a database for trending. The Bulk Radiometric Processing function writes statistical information from the dark data acquired before and after the Earth imagery and the lamp data to the database for trending. This allows for multi-scene statistical analyses.

  2. Advanced power systems for EOS

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila G.; Weinberg, Irving; Flood, Dennis J.

    1991-01-01

    The Earth Observing System, which is part of the International Mission to Planet Earth, is NASA's main contribution to the Global Change Research Program. Five large platforms are to be launched into polar orbit: two by NASA, two by the European Space Agency, and one by the Japanese. In such an orbit the radiation resistance of indium phosphide solar cells combined with the potential of utilizing 5 micron cell structures yields an increase of 10 percent in the payload capability. If further combined with the Advanced Photovoltaic Solar Array, the total additional payload capability approaches 12 percent.

  3. Advanced power systems for EOS

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila G.; Weinberg, Irving; Flood, Dennis J.

    1991-01-01

    The Earth Observing System (EOS), which is part of the International Mission to Planet Earth, is NASA's main contribution to the Global Change Research Program. Five large platforms are to be launched into polar orbit: two by NASA, two by the European Space Agency, and one by the Japanese. In such an orbit the radiation resistance of indium phosphide solar cells combined with the potential of utilizing 5-micron cell structures yields an increase of 10 percent in the payload capability. If further combined with the Advanced Photovoltaic Solar Array, the total additional payload capability approaches 12 percent.

  4. MAGNETIC LIQUID DEFORMABLE MIRRORS FOR ASTRONOMICAL APPLICATIONS: ACTIVE CORRECTION OF OPTICAL ABERRATIONS FROM LOWER-GRADE OPTICS AND SUPPORT SYSTEM

    SciTech Connect

    Borra, E. F.

    2012-08-01

    Deformable mirrors are increasingly used in astronomy. However, they still are limited in stroke for active correction of high-amplitude optical aberrations. Magnetic liquid deformable mirrors (MLDMs) are a new technology that has the advantages of high-amplitude deformations and low costs. In this paper, we demonstrate extremely high strokes and interactuator strokes achievable by MLDMs which can be used in astronomical instrumentation. In particular, we consider the use of such a mirror to suggest an interesting application for the next generation of large telescopes. We present a prototype 91 actuator deformable mirror made of a magnetic liquid (ferrofluid). This mirror uses a technique that linearizes the response of such mirrors by superimposing a large and uniform magnetic field on the magnetic field produced by an array of small coils. We discuss experimental results that illustrate the performance of MLDMs. A most interesting application of MLDMs comes from the fact they could be used to correct the aberrations of large and lower optical quality primary mirrors held by simple support systems. We estimate basic parameters of the needed MLDMs, obtaining reasonable values.

  5. Application of MEMS Accelerometers and Gyroscopes in Fast Steering Mirror Control Systems.

    PubMed

    Tian, Jing; Yang, Wenshu; Peng, Zhenming; Tang, Tao; Li, Zhijun

    2016-01-01

    In a charge-coupled device (CCD)-based fast steering mirror (FSM) tracking control system, high control bandwidth is the most effective way to enhance the closed-loop performance. However, the control system usually suffers a great deal from mechanical resonances and time delays induced by the low sampling rate of CCDs. To meet the requirements of high precision and load restriction, fiber-optic gyroscopes (FOGs) are usually used in traditional FSM tracking control systems. In recent years, the MEMS accelerometer and gyroscope are becoming smaller and lighter and their performance have improved gradually, so that they can be used in a fast steering mirror (FSM) to realize the stabilization of the line-of-sight (LOS) of the control system. Therefore, a tentative approach to implement a CCD-based FSM tracking control system, which uses MEMS accelerometers and gyroscopes as feedback components and contains an acceleration loop, a velocity loop and a position loop, is proposed. The disturbance suppression of the proposed method is the product of the error attenuation of the acceleration loop, the velocity loop and the position loop. Extensive experimental results show that the MEMS accelerometers and gyroscopes can act the similar role as the FOG with lower cost for stabilizing the LOS of the FSM tracking control system. PMID:27023557

  6. Using geometric algebra to understand pattern rotations in multiple mirror optical systems

    SciTech Connect

    Hanlon, J.; Ziock, H.

    1997-05-01

    Geometric Algebra (GA) is a new formulation of Clifford Algebra that includes vector analysis without notation changes. Most applications of Ga have been in theoretical physics, but GA is also a very good analysis tool for engineering. As an example, the authors use GA to study pattern rotation in optical systems with multiple mirror reflections. The common ways to analyze pattern rotations are to use rotation matrices or optical ray trace codes, but these are often inconvenient. The authors use GA to develop a simple expression for pattern rotation that is useful for designing or tolerancing pattern rotations in a multiple mirror optical system by inspection. Pattern rotation is used in many optical engineering systems, but it is not normally covered in optical system engineering texts. Pattern rotation is important in optical systems such as: (1) the 192 beam National ignition Facility (NIF), which uses square laser beams in close packed arrays to cut costs; (2) visual optical systems, which use pattern rotation to present the image to the observer in the appropriate orientation, and (3) the UR90 unstable ring resonator, which uses pattern rotation to fill a rectangular laser gain region and provide a filled-in laser output beam.

  7. Application of MEMS Accelerometers and Gyroscopes in Fast Steering Mirror Control Systems.

    PubMed

    Tian, Jing; Yang, Wenshu; Peng, Zhenming; Tang, Tao; Li, Zhijun

    2016-01-01

    In a charge-coupled device (CCD)-based fast steering mirror (FSM) tracking control system, high control bandwidth is the most effective way to enhance the closed-loop performance. However, the control system usually suffers a great deal from mechanical resonances and time delays induced by the low sampling rate of CCDs. To meet the requirements of high precision and load restriction, fiber-optic gyroscopes (FOGs) are usually used in traditional FSM tracking control systems. In recent years, the MEMS accelerometer and gyroscope are becoming smaller and lighter and their performance have improved gradually, so that they can be used in a fast steering mirror (FSM) to realize the stabilization of the line-of-sight (LOS) of the control system. Therefore, a tentative approach to implement a CCD-based FSM tracking control system, which uses MEMS accelerometers and gyroscopes as feedback components and contains an acceleration loop, a velocity loop and a position loop, is proposed. The disturbance suppression of the proposed method is the product of the error attenuation of the acceleration loop, the velocity loop and the position loop. Extensive experimental results show that the MEMS accelerometers and gyroscopes can act the similar role as the FOG with lower cost for stabilizing the LOS of the FSM tracking control system.

  8. Application of MEMS Accelerometers and Gyroscopes in Fast Steering Mirror Control Systems

    PubMed Central

    Tian, Jing; Yang, Wenshu; Peng, Zhenming; Tang, Tao; Li, Zhijun

    2016-01-01

    In a charge-coupled device (CCD)-based fast steering mirror (FSM) tracking control system, high control bandwidth is the most effective way to enhance the closed-loop performance. However, the control system usually suffers a great deal from mechanical resonances and time delays induced by the low sampling rate of CCDs. To meet the requirements of high precision and load restriction, fiber-optic gyroscopes (FOGs) are usually used in traditional FSM tracking control systems. In recent years, the MEMS accelerometer and gyroscope are becoming smaller and lighter and their performance have improved gradually, so that they can be used in a fast steering mirror (FSM) to realize the stabilization of the line-of-sight (LOS) of the control system. Therefore, a tentative approach to implement a CCD-based FSM tracking control system, which uses MEMS accelerometers and gyroscopes as feedback components and contains an acceleration loop, a velocity loop and a position loop, is proposed. The disturbance suppression of the proposed method is the product of the error attenuation of the acceleration loop, the velocity loop and the position loop. Extensive experimental results show that the MEMS accelerometers and gyroscopes can act the similar role as the FOG with lower cost for stabilizing the LOS of the FSM tracking control system. PMID:27023557

  9. Disassembling and reintegration of large telescope primary mirror

    NASA Astrophysics Data System (ADS)

    Xu, Qi-rui; Fan, Bin; Zhang, Ming

    2014-09-01

    The success of the large telescope is largely linked to the excellent performance and reliability of the primary mirror. In order to maintain the quality of its reflective surface at the high expectations of astronomers, the primary mirror after almost two or three years of astronomical observations, needs to be removed and reinstalled for its cleaning and re-coating operation. There are a series of procedures such as the primary mirror cell dissembling from telescope, mirror handling, transportation, reintegration, alignment and so on. This paper will describe the experiences of disassembling and reintegration of large telescope primary mirror, taking a two meter grade primary mirror for example. As with all advanced and complex opto-mechanical systems, there has been the usual problems and trouble shooting.

  10. Final Results of the Ball AMSD Beryllium Mirror

    NASA Technical Reports Server (NTRS)

    Chaney, David M.

    2004-01-01

    The 1.4-meter semi-rigid, beryllium Advanced Mirror System Demonstrator (AMSD) mirror completed initial cryogenic testing at Marshall's X-ray Calibration Facility (XRCF) in August of 2003. Results of this testing show the mirror to have very low cryogenic surface deformation and possess exceptional figure stability. Subsequent to this cryogenic testing beryllium was selected as the material of choice for the James Webb Space Telescope (JWST) multi-segment primary mirror. Therefore, the AMSD mirror was sent back to SSG-Tinsley for additional ambient polishing to JWST requirements. The mirror was successfully polished to less than 22nm rms of low frequency error. Those additional results are presented with comparisons to the JWST requirements.

  11. Optical stabilization system based on deformable mirrors for retina-like sensors.

    PubMed

    Hao, Qun; Fan, Fan; Cheng, Xuemin; Wang, Dongdong; Jiang, Yang

    2016-07-20

    This paper presents an optical stabilization system based on deformable mirrors (DMs) for retina-like sensors. This system achieves image stabilization by changing the reflective plate of the DM's compensating tilt angle. The mathematical model is constructed with relative parameters, and the simulation experiments and parameter analysis are discussed to verify the system's reliability. The experimental results show that this system achieved optical image stabilization. The maximum relative error of the compensation angle is 8.78%. The system is close to the diffraction limit, and the distortion is less than 0.33%. This study presents an image stabilization system and offers possible improvement in the aberrations in the system, which will provide great support to retina-like sensors.

  12. Optical stabilization system based on deformable mirrors for retina-like sensors.

    PubMed

    Hao, Qun; Fan, Fan; Cheng, Xuemin; Wang, Dongdong; Jiang, Yang

    2016-07-20

    This paper presents an optical stabilization system based on deformable mirrors (DMs) for retina-like sensors. This system achieves image stabilization by changing the reflective plate of the DM's compensating tilt angle. The mathematical model is constructed with relative parameters, and the simulation experiments and parameter analysis are discussed to verify the system's reliability. The experimental results show that this system achieved optical image stabilization. The maximum relative error of the compensation angle is 8.78%. The system is close to the diffraction limit, and the distortion is less than 0.33%. This study presents an image stabilization system and offers possible improvement in the aberrations in the system, which will provide great support to retina-like sensors. PMID:27463916

  13. NONLINEAR OPTICAL PHENOMENA AND DEVICES: Delay effects in a system formed by a bistable thin film and a mirror

    NASA Astrophysics Data System (ADS)

    Loiko, N. A.; Logvin, Yu A.; Samson, A. M.

    1995-04-01

    A theoretical investigation is made of the dynamics of the interaction of light with a bistable system formed by a thin film and a feedback mirror. The dependence of the dynamics on the ratio of the relaxation time of a two-level medium to the delay associated with the transmission of light from the film to the mirror and back again is determined. The reasons and conditions for the appearance of regular pulsations and of more complex dynamics are found.

  14. Self in the mirror.

    PubMed

    Prinz, Wolfgang

    2013-09-01

    What are mirror systems good for? Several suggestions have been made in response to this question, addressing the putative functions of mirror systems in minds and brains. This paper examines possible contributions of mirror systems to the emergence of subjectivity. At the heart of the discussion is the notion of social mirroring, which has a long tradition in social philosophy and social anthropology. Taking the existence of mirror devices in minds and brains for granted, I argue that social mirroring is a prerequisite for the constitution of mental selves, and, hence, the emergence of subjectivity. However, the fact that self and subjectivity are socially created should not be taken to indicate that they are illusory. They are as real as natural facts are. PMID:23410785

  15. Advanced Docking Berthing System Update

    NASA Technical Reports Server (NTRS)

    Lewis, James

    2006-01-01

    In FY05 the Exploration Systems Technology Maturation Program selected the JSC advanced mating systems development to continue as an in-house project. In FY06, as a result of ESAS Study (60 Day Study) the CEV Project (within the Constellation Program) has chosen to continue the project as a GFE Flight Hardware development effort. New requirement for CEV to travel and dock with the ISS in 2011/12 in support of retiring the Shuttle and reducing the gap of time where US does not have any US based crew launch capability. As before, long-duration compatible seal-on-seal technology (seal-on-seal to support androgynous interface) has been identified as a risk mitigation item.

  16. Laser scanning thermoreflectance imaging system using galvanometric mirrors for temperature measurements of microelectronic devices.

    PubMed

    Grauby, S; Salhi, A; Rampnoux, J-M; Michel, H; Claeys, W; Dilhaire, S

    2007-07-01

    We present a thermoreflectance imaging system using a focused laser sweeping the device under test with a scanner made of galvanometric mirrors. We first show that the spatial resolution of this setup is submicrometric, which makes it adapted to microelectronic thermal measurements. Then, we studied qualitative temperature variations on two dissipative structures constituted of thin (0.35 microm) dissipative resistors, the distance between two resistors being equal to 0.8 or 10 microm. This technique combines sensitivity and speed: it is faster than a point classical thermoreflectance technique and, in addition, more sensitive than a charge-coupled device thermoreflectance imaging technique.

  17. Dyadic brain modelling, mirror systems and the ontogenetic ritualization of ape gesture

    PubMed Central

    Arbib, Michael; Ganesh, Varsha; Gasser, Brad

    2014-01-01

    The paper introduces dyadic brain modelling, offering both a framework for modelling the brains of interacting agents and a general framework for simulating and visualizing the interactions generated when the brains (and the two bodies) are each coded up in computational detail. It models selected neural mechanisms in ape brains supportive of social interactions, including putative mirror neuron systems inspired by macaque neurophysiology but augmented by increased access to proprioceptive state. Simulation results for a reduced version of the model show ritualized gesture emerging from interactions between a simulated child and mother ape. PMID:24778382

  18. Advanced Space Surface Systems Operations

    NASA Technical Reports Server (NTRS)

    Huffaker, Zachary Lynn; Mueller, Robert P.

    2014-01-01

    The importance of advanced surface systems is becoming increasingly relevant in the modern age of space technology. Specifically, projects pursued by the Granular Mechanics and Regolith Operations (GMRO) Lab are unparalleled in the field of planetary resourcefulness. This internship opportunity involved projects that support properly utilizing natural resources from other celestial bodies. Beginning with the tele-robotic workstation, mechanical upgrades were necessary to consider for specific portions of the workstation consoles and successfully designed in concept. This would provide more means for innovation and creativity concerning advanced robotic operations. Project RASSOR is a regolith excavator robot whose primary objective is to mine, store, and dump regolith efficiently on other planetary surfaces. Mechanical adjustments were made to improve this robot's functionality, although there were some minor system changes left to perform before the opportunity ended. On the topic of excavator robots, the notes taken by the GMRO staff during the 2013 and 2014 Robotic Mining Competitions were effectively organized and analyzed for logistical purposes. Lessons learned from these annual competitions at Kennedy Space Center are greatly influential to the GMRO engineers and roboticists. Another project that GMRO staff support is Project Morpheus. Support for this project included successfully producing mathematical models of the eroded landing pad surface for the vertical testbed vehicle to predict a timeline for pad reparation. And finally, the last project this opportunity made contribution to was Project Neo, a project exterior to GMRO Lab projects, which focuses on rocket propulsion systems. Additions were successfully installed to the support structure of an original vertical testbed rocket engine, thus making progress towards futuristic test firings in which data will be analyzed by students affiliated with Rocket University. Each project will be explained in

  19. Derivation of line-of-sight stabilization equations for gimbaled-mirror optical systems

    NASA Astrophysics Data System (ADS)

    Debruin, James C.

    1992-01-01

    The gimbaled flat steering mirrors commonly used for pointing the outgoing line-of-sight of optical systems can also be driven to stabilize the line-of-sight, effectively isolating it from vehicle base motion. The stabilization equations provide the relative rates of the gimbal angles as functions of the angular velocity of the base. These equations are of use in feed-forward stabilization systems. Two algorithmic methods of deriving the stabilization equations are presented. These methods are distinguished from others by their use of a kinematic reference frame that is attached to the line-of-sight. The first method is completely general and can be applied to any system. The second is limited to systems of a specific configuration, but allows direct generation of uncoupled stabilization equations. Analysis of an aerial photography system is presented as an example.

  20. The Mirror Fusion Test Facility cryogenic system: Performance, management approach, and present equipment status

    SciTech Connect

    Slack, D.S.; Chronis, W.C.

    1987-06-08

    The cryogenic system for the Mirror Fusion Test Facility (MFTF) is a 14-kW, 4.35-K helium refrigeration system that proved to be highly successful and cost-effective. All operating objectives were met, while remaining within a few percent of initial cost and schedule plans. The management approach used in MFTF allowed decisions to be made quickly and effectively, and it helped keep costs down. Manpower levels, extent and type of industrial participation, key aspects of subcontractor specifications, and subcontractor interactions are reviewed, as well as highlights of the system tests, operation, and present equipment status. Organizations planning large, high-technology systems may benefit from this experience with the MFTF cryogenic system.

  1. Design and analysis of the internally cooled silicon mirrors and benders for wiggler sources at the Advanced Photon Source

    SciTech Connect

    Schildkamp, W.; Jaski, Y.; Tonnessen, T.; Douglas, G.

    1996-09-01

    When silicon single crystal mirrors are bent to cylindrical figures of typically 6 km bending radius, the moments needed are very small and easy to disturb by cooling attachments to the sides of the mirror. Hence, we decided to abandon the conventional concept of cooling plates attached to the sides of the mirrors and instead have chosen to use internal water channels. We present here the design of mirrors with cooling channels near the neutral axis of the silicon beam that have a rather thick {open_quote}{open_quote}hot wall.{close_quote}{close_quote} The results of this analytical work are nonintuitive, regarding the stresses produced by wiggler heating. The design path chosen minimizes figure errors due to coolant pressure variations and residual stresses from machining and bonding of multiple layers of silicon. The geometry of the water channels avoids water-to-vacuum seals and uses the mirror bender as the coolant manifold. Engineering efforts, which reduce the bending stresses at bender-to-silicon interface by a factor of five, will be presented. The complete mirror bender and motion control mechanics will be shown. {copyright} {ital 1996 American Institute of Physics.}

  2. Design of off-axis four-mirror optical system without obscuration based on free-form surface

    NASA Astrophysics Data System (ADS)

    Huang, Chenxu; Liu, Xin

    2015-11-01

    With the development of modern military technology, the requirements of airborne electro-optical search and tracking system are increasing on target detection and recognition. However, traditional off-axis three-mirror system couldn't meet the requirements for reducing weight and compacting size in some circumstances. Based on Seidel aberration theory, by restricting the aberration functions, the optical system could achieve initial construction parameters. During the designing process, decenters and tilts of mirrors were adjusted continuously to eliminate the obscurations. To balance off-axis aberration and increase angle of view, the free-form mirror was introduced into the optical system. Then an unobstructed optical system with effective focal length of 100 mm, FOV of 16°×16°, and relative aperture as F/7 is designed. The results show that the system structure is compact, with imaging qualities approaching diffraction limit.

  3. On The Problem Of In-vessel Mirrors For Diagnostic Systems Of ITER

    SciTech Connect

    Voitsenya, V. S.; Litnovsky, A.

    2008-03-12

    The present status of the investigations with ITER-candidate mirror materials and directed on solution of the in-vessel mirror problem, are presented in the paper. The current tasks in the R and D of diagnostic mirrors and outstanding questions are discussed.

  4. The application of frequency characteristics test in fast control mirror system

    NASA Astrophysics Data System (ADS)

    Gan, Xun; Jang, Yu; Wang, Zong You; Mao, Yao

    2015-10-01

    The control bandwidth of the FSM affects directly on the performance of the tracking system based on the compound axis servo structure. The FSM's control system's accuracy affects the bandwidth and the tracking precision of the system directly. Obtaining the accurate transfer function of the control object is the basis of designing frequency characteristics based control system. Measurement of high precision transfer function is needed to compensate the influence of the mechanical resonance. The mechanical resonance of fast control mirror is mainly of high frequency. In this case, the measured signal's SNR is low so that the measurement accuracy of the frequency characteristic is reduced accordingly. One way to get frequency characteristics is to input sweeping sine drive signal to the system, measure the output of system, and then calculate the frequency characteristics by Fourier Transformation. However, the measuring result of the FSM system that has a low SNR in high frequency is not precise enough as in a system with a high SNR. To solve the problem mentioned above, this article presents a method to calculate frequency characteristics of an FSM system. This method uses the least squares to fit the fast mirror output overall waveform and the input source can be sine, white noise, multimode signal or chirp signal. A digital compensator based on this method is introduced to experimentally verify the efficiency of the method. Experiment results show that fitting the system's output curve in high frequency can effectively eliminate influence of quantization noise, gauss measurement noise and harmonic interference on the measurement accuracy and thus enhance the measuring signal's SNR. It is proved that by using this method a more accurate frequency characteristics of the FSM can be obtained.

  5. Phase conjugate mirror system consisting of a rod amplifier and a nonlinear medium

    NASA Astrophysics Data System (ADS)

    Lee, Hak K.; Lee, Sang-Soo

    1990-07-01

    The phase conjugate (PC) mirror system consisting of a rod amplifier and a nonlinear medium is presented and the theoretical analysis of the enhanced PC wave in the system is derived by taking into account of the overlap of the probe and counterpropagating PC wave in the amplifier. In order to examine experimentally the enhanced PC reflectivity in degenerate four wave mixing (DFWM) an amplifier is placed in the probe beam path. Experimental result of maximal R/R 90. 25 is obtained where R and R are PC reflectivities in the absence and presence of the amplifier respectively. The experimental results agree within 5 with the theoretical values. 1. THEORETICAL ANALYSIS Schematic digram of the PC mirror system consisting of an amplifier and a nonlinear medium is shown in Fig. 1. The phase distortion 4 is due to several effects such as inhomogemous pumping stress gain saturation thermal leasing and self-focusing/defocusing in the amplifier. 1 The amplifier is palced near the nonlinear medium so that the changes in phase (4) and gain (g) are negligible during the round trip time. Considering phase conjugation at the nonlinear medium the output signal SA8 over the input probe bA. is expressed as 8A ge+/ (ge14''A) J where R is PC reflectivity of nonlinear medium. There is no phase distortion term in output signal. Thus we obtain the following expression for the signal 6M photons/ 2

  6. Passive Faraday-mirror attack in a practical two-way quantum-key-distribution system

    SciTech Connect

    Sun Shihai; Jiang Musheng; Liang Linmei

    2011-06-15

    The Faraday mirror (FM) plays a very important role in maintaining the stability of two-way plug-and-play quantum key distribution (QKD) systems. However, the practical FM is imperfect, which will not only introduce an additional quantum bit error rate (QBER) but also leave a loophole for Eve to spy the secret key. In this paper we propose a passive Faraday mirror attack in two-way QKD system based on the imperfection of FM. Our analysis shows that if the FM is imperfect, the dimension of Hilbert space spanned by the four states sent by Alice is three instead of two. Thus Eve can distinguish these states with a set of Positive Operator Valued Measure (POVM) operators belonging to three-dimension space, which will reduce the QBER induced by her attack. Furthermore, a relationship between the degree of the imperfection of FM and the transmittance of the practical QKD system is obtained. The results show that the probability that Eve loads her attack successfully depends on the degree of the imperfection of FM rapidly, but the QBER induced by Eve's attack changes slightly with the degree of the FM imperfection.

  7. Passive Faraday-mirror attack in a practical two-way quantum-key-distribution system

    NASA Astrophysics Data System (ADS)

    Sun, Shi-Hai; Jiang, Mu-Sheng; Liang, Lin-Mei

    2011-06-01

    The Faraday mirror (FM) plays a very important role in maintaining the stability of two-way plug-and-play quantum key distribution (QKD) systems. However, the practical FM is imperfect, which will not only introduce an additional quantum bit error rate (QBER) but also leave a loophole for Eve to spy the secret key. In this paper we propose a passive Faraday mirror attack in two-way QKD system based on the imperfection of FM. Our analysis shows that if the FM is imperfect, the dimension of Hilbert space spanned by the four states sent by Alice is three instead of two. Thus Eve can distinguish these states with a set of Positive Operator Valued Measure (POVM) operators belonging to three-dimension space, which will reduce the QBER induced by her attack. Furthermore, a relationship between the degree of the imperfection of FM and the transmittance of the practical QKD system is obtained. The results show that the probability that Eve loads her attack successfully depends on the degree of the imperfection of FM rapidly, but the QBER induced by Eve’s attack changes slightly with the degree of the FM imperfection.

  8. OPTIMIZATION OF ADVANCED FILTER SYSTEMS

    SciTech Connect

    R.A. Newby; M.A. Alvin; G.J. Bruck; T.E. Lippert; E.E. Smeltzer; M.E. Stampahar

    2002-06-30

    Two advanced, hot gas, barrier filter system concepts have been proposed by the Siemens Westinghouse Power Corporation to improve the reliability and availability of barrier filter systems in applications such as PFBC and IGCC power generation. The two hot gas, barrier filter system concepts, the inverted candle filter system and the sheet filter system, were the focus of bench-scale testing, data evaluations, and commercial cost evaluations to assess their feasibility as viable barrier filter systems. The program results show that the inverted candle filter system has high potential to be a highly reliable, commercially successful, hot gas, barrier filter system. Some types of thin-walled, standard candle filter elements can be used directly as inverted candle filter elements, and the development of a new type of filter element is not a requirement of this technology. Six types of inverted candle filter elements were procured and assessed in the program in cold flow and high-temperature test campaigns. The thin-walled McDermott 610 CFCC inverted candle filter elements, and the thin-walled Pall iron aluminide inverted candle filter elements are the best candidates for demonstration of the technology. Although the capital cost of the inverted candle filter system is estimated to range from about 0 to 15% greater than the capital cost of the standard candle filter system, the operating cost and life-cycle cost of the inverted candle filter system is expected to be superior to that of the standard candle filter system. Improved hot gas, barrier filter system availability will result in improved overall power plant economics. The inverted candle filter system is recommended for continued development through larger-scale testing in a coal-fueled test facility, and inverted candle containment equipment has been fabricated and shipped to a gasifier development site for potential future testing. Two types of sheet filter elements were procured and assessed in the program

  9. A Ray-Tracing Study of the Dependence of Focal Properties on Surface Figure Error for a Kirkpatrick-Baez (K-B) Mirror System

    SciTech Connect

    Xu, S.; Fischetti, R.F.

    2004-05-12

    In the last several years, Kirkpatrick-Baez (K-B) mirror systems have been extensively applied as two-dimensional x-ray focusing elements on x-ray beamlines at low emittance, third generation, synchrotron radiation facilities. The design of the two GM/CA CAT insertion device beamlines at the Advanced Photon Source at Argonne National Laboratory for macromolecular crystallography includes a K-B mirror system situated in each of the experimental stations. Ray-tracing studies have been performed using SHADOW (V2.3.2) to investigate the dependence of the focal distance on the surface figure error obtained from LTP metrology measurements. Additionally, a procedure has been developed to allow one to change the mirror focal positions to provide a beam of given dimensions at a fixed position before or after the focal position. The GM/CA CAT has been established by the National Institutes of Health's (NIH) National Institute of General Medical Sciences (NIGMS), and the National Cancer Institute (NCI) to build and operate a national user facility for crystallographic structure determination of biological macromolecules by X-ray diffraction.

  10. The Advanced Launch System (ALS)

    NASA Astrophysics Data System (ADS)

    Eldred, Charles H.

    The Advanced Launch System (ALS) is an unmanned vehicle that will achieve low hardware cost by using a reusable booster stage which flies back to the launch site, and a core stage in which the rocket engines and redundant avionics are in a module that is returned to earth and recovered for reuse. The booster's utilization of liquid propellant instead of solid propellant will help lower the consumable costs. The ALS also includes launch processing and flight control facilities, necessary support equipment, and ground- and flight-operations infrastructure. The ALS program studies show that, through the ALS, the United States can launch a major Mars initiative economically and with confidence. It is estimated that the objective ALS can be operational in the late 1990s.

  11. Application of modern-control-design methodologies to a multi-segmented deformable-mirror system. Master's thesis

    SciTech Connect

    Vaughan, E.M.

    1991-05-23

    The multi-segmented deformable mirror system is proposed as an element for a portion of a ballistic missile defense system. The size of the mirror required for this defense function requires that the mirror be developed in segments, and then these segments should be phased together to produce one continuous, large optic. The application of multivariable control system synthesis techniques to provide closed-loop wavefront control of the deformable mirror system is the problem discussed in this thesis. The method of H at infinity control system synthesis using loop-shaping techniques was used to develop a controller that meets a robust performance specification. The number and location of sensors was treated as a design variable, and the structured singular value (mu) was used to determine the performance robustness of the deformable mirror system. Decentralized control issues are also addressed through the use of necessary conditions in an effort to determine a suitable decentralized control structure with performance similar to that of the centralized controller.

  12. Advanced integrated solvent extraction systems

    SciTech Connect

    Horwitz, E.P.; Dietz, M.L.; Leonard, R.A.

    1997-10-01

    Advanced integrated solvent extraction systems are a series of novel solvent extraction (SX) processes that will remove and recover all of the major radioisotopes from acidic-dissolved sludge or other acidic high-level wastes. The major focus of this effort during the last 2 years has been the development of a combined cesium-strontium extraction/recovery process, the Combined CSEX-SREX Process. The Combined CSEX-SREX Process relies on a mixture of a strontium-selective macrocyclic polyether and a novel cesium-selective extractant based on dibenzo 18-crown-6. The process offers several potential advantages over possible alternatives in a chemical processing scheme for high-level waste treatment. First, if the process is applied as the first step in chemical pretreatment, the radiation level for all subsequent processing steps (e.g., transuranic extraction/recovery, or TRUEX) will be significantly reduced. Thus, less costly shielding would be required. The second advantage of the Combined CSEX-SREX Process is that the recovered Cs-Sr fraction is non-transuranic, and therefore will decay to low-level waste after only a few hundred years. Finally, combining individual processes into a single process will reduce the amount of equipment required to pretreat the waste and therefore reduce the size and cost of the waste processing facility. In an ongoing collaboration with Lockheed Martin Idaho Technology Company (LMITCO), the authors have successfully tested various segments of the Advanced Integrated Solvent Extraction Systems. Eichrom Industries, Inc. (Darien, IL) synthesizes and markets the Sr extractant and can supply the Cs extractant on a limited basis. Plans are under way to perform a test of the Combined CSEX-SREX Process with real waste at LMITCO in the near future.

  13. Research on shaftless fast-steering mirror used in a precision tracking-aiming system

    NASA Astrophysics Data System (ADS)

    Zhou, Jianmin; Yin, Hongyan; Wang, Yonghui; Guo, Jin

    2007-12-01

    Based on the analysis of principle of tracking and aiming system, some important factors to design the structure of tracking-aiming system and the layout of optical system are discussed. Besides, the paper gives the present developing situation of fast-steering mirror at home and abroad, analyzes the advantages and disadvantages of FSM with axis, and presents a novel design of flexible axis FSM. The main axis of composite axis system is tracked by motor to drive the frame, and the sub-axis is tracked by voice coil motor (VCM) to drive FSM. The structure of FSM and designing principle of VCM are introduced, and the emulation analyses of inherent frequency and deformation under load of the FSM with software COSMOS are also given.

  14. A one-dimensional ion beam figuring system for x-ray mirror fabrication

    SciTech Connect

    Idir, Mourad Huang, Lei; Bouet, Nathalie; Kaznatcheev, Konstantine; Vescovi, Matthew; Lauer, Ken; Conley, Ray; Rennie, Kent; Kahn, Jim; Nethery, Richard; Zhou, Lin

    2015-10-15

    We report on the development of a one-dimensional Ion Beam Figuring (IBF) system for x-ray mirror polishing. Ion beam figuring provides a highly deterministic method for the final precision figuring of optical components with advantages over conventional methods. The system is based on a state of the art sputtering deposition system outfitted with a gridded radio frequency inductive coupled plasma ion beam source equipped with ion optics and dedicated slit developed specifically for this application. The production of an IBF system able to produce an elongated removal function rather than circular is presented in this paper, where we describe in detail the technical aspect and present the first obtained results.

  15. Supervisory control and diagnostics system for the mirror fusion test facility: overview and status 1980

    SciTech Connect

    McGoldrick, P.R.

    1981-01-01

    The Mirror Fusion Test Facility (MFTF) is a complex facility requiring a highly-computerized Supervisory Control and Diagnostics System (SCDS) to monitor and provide control over ten subsystems; three of which require true process control. SCDS will provide physicists with a method of studying machine and plasma behavior by acquiring and processing up to four megabytes of plasma diagnostic information every five minutes. A high degree of availability and throughput is provided by a distributed computer system (nine 32-bit minicomputers on shared memory). Data, distributed across SCDS, is managed by a high-bandwidth Distributed Database Management System. The MFTF operators' control room consoles use color television monitors with touch sensitive screens; this is a totally new approach. The method of handling deviations to normal machine operation and how the operator should be notified and assisted in the resolution of problems has been studied and a system designed.

  16. The Gemini secondary mirror tip/tilt system: past, present, and future

    NASA Astrophysics Data System (ADS)

    Carter, Christopher J.; Rippa, Mathew J.; Rojas, Roberto; Sheehan, Michael P.

    2008-07-01

    The Gemini Observatory is currently in the early stages of a major upgrade of the Secondary Mirror Tip/tilt Systems (M2TS). Although these systems continue to deliver good fast-steering and chopping performance at both sites, there are persistent and occasionally time-consuming issues that need to be addressed in order for them to deliver their full potential and further reduce downtime. We present an overview of the system, outline its capabilities, and review the early commissioning process and some of the issues encountered. We describe the augmentation of the original system with data logging features which made possible some critical servo tuning work that was key in delivering improved performance. The hardware and software upgrade project to date is discussed, along with a brief overview of items it intends to address.

  17. A one-dimensional ion beam figuring system for x-ray mirror fabrication

    SciTech Connect

    Idir, Mourad; Huang, Lei; Bouet, Nathalie; Kaznatcheev, Konstantine; Vescovi, Matthew; Lauer, Ken; Conley, Ray; Rennie, Kent; Kahn, Jim; Nethery, Richard; Zhou, Lin

    2015-10-01

    We report on the development of a one-dimensional Ion Beam Figuring (IBF) system for x-ray mirror polishing. Ion beam figuring provides a highly deterministic method for the final precision figuring of optical components with advantages over conventional methods. The system is based on a state of the art sputtering deposition system outfitted with a gridded radio frequency inductive coupled plasma ion beam source equipped with ion optics and dedicated slit developed specifically for this application. The production of an IBF system able to produce an elongated removal function rather than circular is presented in this paper, where we describe in detail the technical aspect and present the first obtained results. (C) 2015 AIP Publishing LLC.

  18. A one-dimensional ion beam figuring system for x-ray mirror fabrication.

    PubMed

    Idir, Mourad; Huang, Lei; Bouet, Nathalie; Kaznatcheev, Konstantine; Vescovi, Matthew; Lauer, Ken; Conley, Ray; Rennie, Kent; Kahn, Jim; Nethery, Richard; Zhou, Lin

    2015-10-01

    We report on the development of a one-dimensional Ion Beam Figuring (IBF) system for x-ray mirror polishing. Ion beam figuring provides a highly deterministic method for the final precision figuring of optical components with advantages over conventional methods. The system is based on a state of the art sputtering deposition system outfitted with a gridded radio frequency inductive coupled plasma ion beam source equipped with ion optics and dedicated slit developed specifically for this application. The production of an IBF system able to produce an elongated removal function rather than circular is presented in this paper, where we describe in detail the technical aspect and present the first obtained results.

  19. A one-dimensional ion beam figuring system for x-ray mirror fabrication.

    PubMed

    Idir, Mourad; Huang, Lei; Bouet, Nathalie; Kaznatcheev, Konstantine; Vescovi, Matthew; Lauer, Ken; Conley, Ray; Rennie, Kent; Kahn, Jim; Nethery, Richard; Zhou, Lin

    2015-10-01

    We report on the development of a one-dimensional Ion Beam Figuring (IBF) system for x-ray mirror polishing. Ion beam figuring provides a highly deterministic method for the final precision figuring of optical components with advantages over conventional methods. The system is based on a state of the art sputtering deposition system outfitted with a gridded radio frequency inductive coupled plasma ion beam source equipped with ion optics and dedicated slit developed specifically for this application. The production of an IBF system able to produce an elongated removal function rather than circular is presented in this paper, where we describe in detail the technical aspect and present the first obtained results. PMID:26520997

  20. Advanced System for Process Engineering

    1998-09-14

    PRO ASPEN/PC1.0 (Advanced System for Process Engineering) is a state of the art process simulator and economic evaluation package which was designed for use in engineering fossil energy conversion processes and has been ported to run on a PC. PRO ASPEN/PC1.0 can represent multiphase streams including solids, and handle complex substances such as coal. The system can perform steady state material and energy balances, determine equipment size and cost, and carry out preliminary economic evaluations.more » It is supported by a comprehensive physical property system for computation of major properties such as enthalpy, entropy, free energy, molar volume, equilibrium ratio, fugacity coefficient, viscosity, thermal conductivity, and diffusion coefficient for specified phase conditions; vapor, liquid, or solid. The properties may be computed for pure components, mixtures, or components in a mixture, as appropriate. The PRO ASPEN/PC1.0 Input Language is oriented towards process engineers.« less

  1. Westinghouse Advanced Particle Filter System

    SciTech Connect

    Lippert, T.E.; Bruck, G.J.; Sanjana, Z.N.; Newby, R.A.; Bachovchin, D.M.

    1996-12-31

    Integrated Gasification Combined Cycles (IGCC) and Pressurized Fluidized Bed Combustion (PFBC) are being developed and demonstrated for commercial, power generation application. Hot gas particulate filters are key components for the successful implementation of IGCC and PFBC in power generation gas turbine cycles. The objective of this work is to develop and qualify through analysis and testing a practical hot gas ceramic barrier filter system that meets the performance and operational requirements of PFBC and IGCC systems. This paper reports on the development and status of testing of the Westinghouse Advanced Hot Gas Particle Filter (W-APF) including: W-APF integrated operation with the American Electric Power, 70 MW PFBC clean coal facility--approximately 6000 test hours completed; approximately 2500 hours of testing at the Hans Ahlstrom 10 MW PCFB facility located in Karhula, Finland; over 700 hours of operation at the Foster Wheeler 2 MW 2nd generation PFBC facility located in Livingston, New Jersey; status of Westinghouse HGF supply for the DOE Southern Company Services Power System Development Facility (PSDF) located in Wilsonville, Alabama; the status of the Westinghouse development and testing of HGF`s for Biomass Power Generation; and the status of the design and supply of the HGF unit for the 95 MW Pinon Pine IGCC Clean Coal Demonstration.

  2. Advanced integrated enhanced vision systems

    NASA Astrophysics Data System (ADS)

    Kerr, J. R.; Luk, Chiu H.; Hammerstrom, Dan; Pavel, Misha

    2003-09-01

    In anticipation of its ultimate role in transport, business and rotary wing aircraft, we clarify the role of Enhanced Vision Systems (EVS): how the output data will be utilized, appropriate architecture for total avionics integration, pilot and control interfaces, and operational utilization. Ground-map (database) correlation is critical, and we suggest that "synthetic vision" is simply a subset of the monitor/guidance interface issue. The core of integrated EVS is its sensor processor. In order to approximate optimal, Bayesian multi-sensor fusion and ground correlation functionality in real time, we are developing a neural net approach utilizing human visual pathway and self-organizing, associative-engine processing. In addition to EVS/SVS imagery, outputs will include sensor-based navigation and attitude signals as well as hazard detection. A system architecture is described, encompassing an all-weather sensor suite; advanced processing technology; intertial, GPS and other avionics inputs; and pilot and machine interfaces. Issues of total-system accuracy and integrity are addressed, as well as flight operational aspects relating to both civil certification and military applications in IMC.

  3. Overview and status of a mirror fusion propulsion system design study

    NASA Astrophysics Data System (ADS)

    Carpenter, Scott A.; Brennan, Kathleen M.

    1999-09-01

    The main goal of this paper is to describe and emphasize the important discoveries made since 1986 in the engineering design of space fusion propulsion plants. Among the important discoveries are four fundamental design principles (DPs) which should be used when adapting candidate Earth-based fusion-electric power plants to propulsion in space. DP1. Maximize direct access to space for waste radiation. DP2. Operate components as passive radiators whenever possible. DP3. Optimize the plasma characteristics for best specific jet power DP4. Optimize mission capability versus lifetime-mass-to-orbit (LMTO). Another discovery is a design philosophy called IDEAs (Integrated Design Environment Algorithms) which is a tool for discovering new fundamental design principles. These discoveries allowed us to adapt, and then to optimize, an earth-based fusion-electric magnetic-mirror-fusion reactor concept for propulsion in space. The resulting design is called the Mirror Fusion Propulsion System (MFPS); and its design status is reviewed. This work can be used as a general road map for others attempting to convert earth-based designs to propulsion in space. It also has applicability to matter-antimatter propulsion systems engineering.

  4. Fiber faceplate modulation readout in Bi-material micro-cantilever mirror array imaging system

    NASA Astrophysics Data System (ADS)

    Hui, Mei; Xia, Zhengzheng; Liu, Ming; Dong, Liquan; Liu, Xiaohua; Zhao, Yuejin

    2016-05-01

    Fiber faceplate modulation was applied to read out the precise actuation of silicon-based, surface micro-fabricated cantilever mirrors array in optical imaging system. The faceplate was made by ordered bundles consisting of as many as ten thousands fibers. The transmission loss of an individual fiber in the bundles was 0.35dB/cm and the cross talk between neighboring fibers in the faceplate was about 15%. Micro-cantilever mirrors array (Focal-Plane Array (FPA)) which composed of two-level bi-material pixels, absorb incident infrared flux and result in a temperature increase. The temperature distribution of incident flux transformed to the deformation distribution in FPA which has a very big difference in coefficients of thermal expansion. FPA plays the roles of target sensing and has the characteristics of high detection sensitivity. Instead of general filter such as knife edge or pinhole, fiber faceplate modulate the beam reflected by the units of FPA. An optical readout signal brings a visible spectrum into pattern recognition system, yielding a visible image on monitor. Thermal images at room temperature have been obtained. The proposed method permits optical axis compact and image noise suppression.

  5. A Micro Electrical Mechanical Systems (MEMS)-based Cryogenic Deformable Mirror

    NASA Astrophysics Data System (ADS)

    Enya, K.; Kataza, H.; Bierden, P.

    2009-03-01

    We present our first results on the development and evaluation of a cryogenic deformable mirror (DM) based on Micro Electro Mechanical Systems (MEMS) technology. A MEMS silicon-based DM chip with 32 channels, in which each channel is 300 μm × 300 μm in size, was mounted on a silicon substrate in order to minimize distortion and prevent it from being permanently damaged by thermal stresses introduced by cooling. The silicon substrate was oxidized to obtain electric insulation and had a metal fan-out pattern on the surface. For cryogenic tests, we constructed a measurement system consisting of a Fizeau interferometer, a cryostat cooled by liquid N2, zooming optics, electric drivers. The surface of the mirror at 95 K deformed in response to the application of a voltage, and no significant difference was found between the deformation at 95 K and that at room temperature. The power dissipation by the cryogenic DM was also measured, and we suggest that this is small enough for it to be used in a space cryogenic telescope. The properties of the DM remained unchanged after five cycles of vacuum pumping, cooling, warming, and venting. We conclude that fabricating cryogenic DMs employing MEMS technology is a promising approach. Therefore, we intend to develop a more sophisticated device for actual use, and to look for potential applications including the Space Infrared Telescope for Cosmology & Astrophysics (SPICA), and other missions.

  6. Advanced Light Source control system

    SciTech Connect

    Magyary, S.; Chin, M.; Cork, C.; Fahmie, M.; Lancaster, H.; Molinari, P.; Ritchie, A.; Robb, A.; Timossi, C.

    1989-03-01

    The Advanced Light Source (ALS) is a third generation 1--2 GeV synchrotron radiation source designed to provide ports for 60 beamlines. It uses a 50 MeV electron linac and 1.5 GeV, 1 Hz, booster synchrotron for injection into a 1--2 GeV storage ring. Interesting control problems are created because of the need for dynamic closed beam orbit control to eliminate interaction between the ring tuning requirements and to minimize orbit shifts due to ground vibrations. The extremely signal sensitive nature of the experiments requires special attention to the sources of electrical noise. These requirements have led to a control system design which emphasizes connectivity at the accelerator equipment end and a large I/O bandwidth for closed loop system response. Not overlooked are user friendliness, operator response time, modeling, and expert system provisions. Portable consoles are used for local operation of machine equipment. Our solution is a massively parallel system with >120 Mbits/sec I/O bandwidth and >1500 Mips computing power. At the equipment level connections are made using over 600 powerful Intelligent Local Controllers (ILC-s) mounted in 3U size Eurocard slots using fiber-optic cables between rack locations. In the control room, personal computers control and display all machine variables at a 10 Hz rate including the scope signals which are collected though the control system. Commercially available software and industry standards are used extensively. Particular attention is paid to reliability, maintainability and upgradeability. 10 refs., 11 figs.

  7. Advanced information processing system: Local system services

    NASA Technical Reports Server (NTRS)

    Burkhardt, Laura; Alger, Linda; Whittredge, Roy; Stasiowski, Peter

    1989-01-01

    The Advanced Information Processing System (AIPS) is a multi-computer architecture composed of hardware and software building blocks that can be configured to meet a broad range of application requirements. The hardware building blocks are fault-tolerant, general-purpose computers, fault-and damage-tolerant networks (both computer and input/output), and interfaces between the networks and the computers. The software building blocks are the major software functions: local system services, input/output, system services, inter-computer system services, and the system manager. The foundation of the local system services is an operating system with the functions required for a traditional real-time multi-tasking computer, such as task scheduling, inter-task communication, memory management, interrupt handling, and time maintenance. Resting on this foundation are the redundancy management functions necessary in a redundant computer and the status reporting functions required for an operator interface. The functional requirements, functional design and detailed specifications for all the local system services are documented.

  8. Vibration damping for the Segmented Mirror Telescope

    NASA Astrophysics Data System (ADS)

    Maly, Joseph R.; Yingling, Adam J.; Griffin, Steven F.; Agrawal, Brij N.; Cobb, Richard G.; Chambers, Trevor S.

    2012-09-01

    The Segmented Mirror Telescope (SMT) at the Naval Postgraduate School (NPS) in Monterey is a next-generation deployable telescope, featuring a 3-meter 6-segment primary mirror and advanced wavefront sensing and correction capabilities. In its stowed configuration, the SMT primary mirror segments collapse into a small volume; once on location, these segments open to the full 3-meter diameter. The segments must be very accurately aligned after deployment and the segment surfaces are actively controlled using numerous small, embedded actuators. The SMT employs a passive damping system to complement the actuators and mitigate the effects of low-frequency (<40 Hz) vibration modes of the primary mirror segments. Each of the six segments has three or more modes in this bandwidth, and resonant vibration excited by acoustics or small disturbances on the structure can result in phase mismatches between adjacent segments thereby degrading image quality. The damping system consists of two tuned mass dampers (TMDs) for each of the mirror segments. An adjustable TMD with passive magnetic damping was selected to minimize sensitivity to changes in temperature; both frequency and damping characteristics can be tuned for optimal vibration mitigation. Modal testing was performed with a laser vibrometry system to characterize the SMT segments with and without the TMDs. Objectives of this test were to determine operating deflection shapes of the mirror and to quantify segment edge displacements; relative alignment of λ/4 or better was desired. The TMDs attenuated the vibration amplitudes by 80% and reduced adjacent segment phase mismatches to acceptable levels.

  9. Algorithm for the identification of malfunctioning sensors in the control systems of segmented mirror telescopes.

    PubMed

    Chanan, Gary; Nelson, Jerry

    2009-11-10

    The active control systems of segmented mirror telescopes are vulnerable to a malfunction of a few (or even one) of their segment edge sensors, the effects of which can propagate through the entire system and seriously compromise the overall telescope image quality. Since there are thousands of such sensors in the extremely large telescopes now under development, it is essential to develop fast and efficient algorithms that can identify bad sensors so that they can be removed from the control loop. Such algorithms are nontrivial; for example, a simple residual-to-the-fit test will often fail to identify a bad sensor. We propose an algorithm that can reliably identify a single bad sensor and we extend it to the more difficult case of multiple bad sensors. Somewhat surprisingly, the identification of a fixed number of bad sensors does not necessarily become more difficult as the telescope becomes larger and the number of sensors in the control system increases.

  10. Mirror mount

    DOEpatents

    Kuklo, Thomas C.; Bender, Donald A.

    1994-01-01

    A unique lens or mirror mount having adjustable constraints at two key locations to allow for "X" and "Y" tilts of the mirror only. The device uses two pair of flexures of a type such that the pivots of the mirror gimble are rigidly fixed in all planes allowing the device to have zero stacking tolerance and zero wear over time.

  11. Einstein's Mirror

    ERIC Educational Resources Information Center

    Gjurchinovski, Aleksandar; Skeparovski, Aleksandar

    2008-01-01

    Reflection of light from a plane mirror in uniform rectilinear motion is a century-old problem, intimately related to the foundations of special relativity. The problem was first investigated by Einstein in his famous 1905 paper by using the Lorentz transformations to switch from the mirror's rest frame to the frame where the mirror moves at a…

  12. Space Adaptation of Active Mirror Segment Concepts

    NASA Technical Reports Server (NTRS)

    Ames, Gregory H.

    1999-01-01

    This report summarizes the results of a three year effort by Blue Line Engineering Co. to advance the state of segmented mirror systems in several separate but related areas. The initial set of tasks were designed to address the issues of system level architecture, digital processing system, cluster level support structures, and advanced mirror fabrication concepts. Later in the project new tasks were added to provide support to the existing segmented mirror testbed at Marshall Space Flight Center (MSFC) in the form of upgrades to the 36 subaperture wavefront sensor. Still later, tasks were added to build and install a new system processor based on the results of the new system architecture. The project was successful in achieving a number of important results. These include the following most notable accomplishments: 1) The creation of a new modular digital processing system that is extremely capable and may be applied to a wide range of segmented mirror systems as well as many classes of Multiple Input Multiple Output (MIMO) control systems such as active structures or industrial automation. 2) A new graphical user interface was created for operation of segmented mirror systems. 3) The development of a high bit rate serial data loop that permits bi-directional flow of data to and from as many as 39 segments daisy-chained to form a single cluster of segments. 4) Upgrade of the 36 subaperture Hartmann type Wave Front Sensor (WFS) of the Phased Array Mirror, Extendible Large Aperture (PAMELA) testbed at MSFC resulting in a 40 to 5OX improvement in SNR which in turn enabled NASA personnel to achieve many significant strides in improved closed-loop system operation in 1998. 5) A new system level processor was built and delivered to MSFC for use with the PAMELA testbed. This new system featured a new graphical user interface to replace the obsolete and non-supported menu system originally delivered with the PAMELA system. The hardware featured Blue Line's new stackable

  13. Quasi-null lens optical system for the fabrication of an oblate convex ellipsoidal mirror: application to the Wide Angle Camera of the Rosetta space mission.

    PubMed

    Pelizzo, Maria-Guglielmina; Da Deppo, Vania; Naletto, Giampiero; Ragazzoni, Roberto; Novi, Andrea

    2006-08-20

    The design of a quasi-null lens system for the fabrication of an aspheric oblate convex ellipsoidal mirror is presented. The Performance and tolerance of the system have been analyzed. The system has been applied successfully for the fabrication of the primary mirror of the Wide Angle Camera (WAC), the imaging system onboard the Rosetta, the European Space Agency cornerstone mission dedicated to the exploration of a comet. The WAC is based on an off-axis two-mirror configuration, in which the primary mirror is an oblate convex ellipsoid with a significant conic constant.

  14. Impact of resolution in multi-conjugate adaptive optics systems using segmented mirrors

    NASA Astrophysics Data System (ADS)

    Corej, Thomas A.; Schmidt, Jason D.

    2009-08-01

    In moderate-to-strong scintillation, multi-conjugate adaptive optics (MCAO) appears promising to compensate for amplitude and phase fluctuations. In this research, a MCAO system is simulated with a segmented deformable mirror (DM) reshaping the amplitude and the second DM (continuous) flattening the phase after propagation from the segmented mirror. A Gerchberg-Saxton (GS) type algorithm is used with Fresnel propagation between DM planes. The effects of varying the phase's apparent resolution on a segmented DM in the pupil plane is investigated. Results show the mean square error in the reshaped beam decreases as D/ro and Rytov number increase over the range of conditions tested (ro: 0.11 m - 0.36 m). The field-estimated Strehl ratio drops precipitously when the number of subapertures is increased beyond about 36 across, using a branch-pointtolerant unwrapper, due to the presence of branch points. On the second DM, by using the mean of the phase within each subaperture before back propagating to the first DM plane (inside the GS loop), the Strehl ratio was improved 6 - 11 percent using 4 - 19 actuators across. Further a novel method of cascading segmented DMs, of increasingly higher resolution, doing amplitude reshaping followed by a continuous DM to flatten the phase is explored.

  15. Exploring associations between gaze patterns and putative human mirror neuron system activity.

    PubMed

    Donaldson, Peter H; Gurvich, Caroline; Fielding, Joanne; Enticott, Peter G

    2015-01-01

    The human mirror neuron system (MNS) is hypothesized to be crucial to social cognition. Given that key MNS-input regions such as the superior temporal sulcus are involved in biological motion processing, and mirror neuron activity in monkeys has been shown to vary with visual attention, aberrant MNS function may be partly attributable to atypical visual input. To examine the relationship between gaze pattern and interpersonal motor resonance (IMR; an index of putative MNS activity), healthy right-handed participants aged 18-40 (n = 26) viewed videos of transitive grasping actions or static hands, whilst the left primary motor cortex received transcranial magnetic stimulation. Motor-evoked potentials recorded in contralateral hand muscles were used to determine IMR. Participants also underwent eyetracking analysis to assess gaze patterns whilst viewing the same videos. No relationship was observed between predictive gaze and IMR. However, IMR was positively associated with fixation counts in areas of biological motion in the videos, and negatively associated with object areas. These findings are discussed with reference to visual influences on the MNS, and the possibility that MNS atypicalities might be influenced by visual processes such as aberrant gaze pattern. PMID:26236215

  16. Why is your spouse so predictable? Connecting mirror neuron system and self-expansion model of love.

    PubMed

    Ortigue, Stephanie; Bianchi-Demicheli, Francesco

    2008-12-01

    The simulation theory assumes we understand actions and intentions of others through a direct matching process. This matching process activates a complex brain network involving the mirror neuron system (MNS), which is self-related and active when one does something or observes someone else acting. Because social psychology admits that mutual intention's understanding grows in close relationship as love grows, we hypothesize that mirror mechanisms take place in love relationships. The similarities between the mirror matching process and the mutual intention's understanding that occurs when two persons are in love suggest that exposure to love might affect functional and neural mechanisms, thus facilitating the understanding of the beloved's intentions. Congruent with our hypothesis, our preliminary results from 38 subjects strongly suggest a significant facilitation effect of love on understanding the intentions of the beloved (as opposed to control stimuli). Based on these phenomenological, and neurofunctional findings we suggest that the mirror mechanisms are involved in the facilitation effects of love for understanding intentions, and might further be extended to any types of love (e.g., passionate love, maternal love). Love experiences are important not only to the beloved himself, but also to any societal, cultural, and institutional patterns that relate to love. Yet, concerning its subjective character, love experiences are difficult to access. The modern procedures and techniques of socio-cognitive neuroscience make it possible to understand love and self-related experiences not only by the analysis of subjective self-reported questionnaires, but also by approaching the automatic (non-conscious) mirror experiences of love in healthy subjects, and neurological patients with a brain damage within the mirror neuron system. Although the psychology of love is now well admitted, the systematic study of the automatic facilitation effect of love through mirror

  17. Status of Mirror Technology for the Next Generation Space Telescope

    NASA Astrophysics Data System (ADS)

    Jacobson, D. N.

    2000-10-01

    establish credibility that the goals of NGST could be achieved. The past two years of the program has seen major steps in the development of several mirror materials, which not only might have NGST applicability but could also support other programs for other customers. Additionally, a second large mirror procurement, the Advanced Mirror System Demonstrator (AMSD), has been implemented providing a focal point to complete the mirror technology development and lead ultimately to the production of mirrors that will fly on NEXUS (NGST flight experimentand) and NGST. This talk will focus on a status of the mirror technology developed over the past 4 years on the NGST program.

  18. A microprocessor-based position control system for a telescope secondary mirror

    NASA Technical Reports Server (NTRS)

    Lorell, K. R.; Barrows, W. F.; Clappier, R. R.; Lee, G. K.

    1983-01-01

    The pointing requirements for the Shuttle IR Telescope Facility (SIRTF), which consists of an 0.85-m cryogenically cooled IR telescope, call for an image stability of 0.25 arcsec. Attention is presently given to a microprocessor-based position control system developed for the control of the SIRTF secondary mirror, employing a special control law (to minimize energy dissipation), a precision capacitive position sensor, and a specially designed power amplifier/actuator combination. The microprocessor generates the command angular position and rate waveforms in order to maintain a 90 percent dwell time/10 percent transition time ratio independently of chop frequency or amplitude. Performance and test results of a prototype system designed for use with a demonstration model of the SIRTF focal plane fine guidance sensor are presented.

  19. Experimental instrumentation system for the Phased Array Mirror Extendible Large Aperture (PAMELA) test program

    NASA Technical Reports Server (NTRS)

    Boykin, William H., Jr.

    1993-01-01

    Adaptive optics are used in telescopes for both viewing objects with minimum distortion and for transmitting laser beams with minimum beam divergence and dance. In order to test concepts on a smaller scale, NASA MSFC is in the process of setting up an adaptive optics test facility with precision (fraction of wavelengths) measurement equipment. The initial system under test is the adaptive optical telescope called PAMELA (Phased Array Mirror Extendible Large Aperture). Goals of this test are: assessment of test hardware specifications for PAMELA application and the determination of the sensitivities of instruments for measuring PAMELA (and other adaptive optical telescopes) imperfections; evaluation of the PAMELA system integration effort and test progress and recommended actions to enhance these activities; and development of concepts and prototypes of experimental apparatuses for PAMELA.

  20. Advances in Solar Heating and Cooling Systems

    ERIC Educational Resources Information Center

    Ward, Dan S.

    1976-01-01

    Reports on technological advancements in the fields of solar collectors, thermal storage systems, and solar heating and cooling systems. Diagrams aid in the understanding of the thermodynamics of the systems. (CP)

  1. Advanced optical manufacturing digital integrated system

    NASA Astrophysics Data System (ADS)

    Tao, Yizheng; Li, Xinglan; Li, Wei; Tang, Dingyong

    2012-10-01

    It is necessarily to adapt development of advanced optical manufacturing technology with modern science technology development. To solved these problems which low of ration, ratio of finished product, repetition, consistent in big size and high precision in advanced optical component manufacturing. Applied business driven and method of Rational Unified Process, this paper has researched advanced optical manufacturing process flow, requirement of Advanced Optical Manufacturing integrated System, and put forward architecture and key technology of it. Designed Optical component core and Manufacturing process driven of Advanced Optical Manufacturing Digital Integrated System. the result displayed effective well, realized dynamic planning Manufacturing process, information integration improved ratio of production manufactory.

  2. Chiral mirrors

    NASA Astrophysics Data System (ADS)

    Plum, Eric; Zheludev, Nikolay I.

    2015-06-01

    Mirrors are used in telescopes, microscopes, photo cameras, lasers, satellite dishes, and everywhere else, where redirection of electromagnetic radiation is required making them arguably the most important optical component. While conventional isotropic mirrors will reflect linear polarizations without change, the handedness of circularly polarized waves is reversed upon reflection. Here, we demonstrate a type of mirror reflecting one circular polarization without changing its handedness, while absorbing the other. The polarization-preserving mirror consists of a planar metasurface with a subwavelength pattern that cannot be superimposed with its mirror image without being lifted out of its plane, and a conventional mirror spaced by a fraction of the wavelength from the metasurface. Such mirrors enable circularly polarized lasers and Fabry-Pérot cavities with enhanced tunability, gyroscopic applications, polarization-sensitive detectors of electromagnetic waves, and can be used to enhance spectroscopies of chiral media.

  3. Optimization design for the supporting system of 2m telescope primary mirror

    NASA Astrophysics Data System (ADS)

    Zhao, Fu; Wang, Ping; Gong, Yanjue; Zhang, Li; Lin, Jianlong

    2008-12-01

    This paper describes the optimization solution improving the total quality of the primary mirror supporting type. With the methods of Finite element analysis(FEA), Orthogonal experiment and BP Neural Network, the relationship between the structure parameters in primary mirror supporting type and the deformation of the primary mirror is built. With this relationship and Genetic Algorithm(GA) optimization design, a group of reasonable technology parameters is found that can improve the static stiffness of the primary mirror supporting type so as to reduce the gravity deformation of the primary mirror. The modal analysis and random vibration analysis are also discussed in detail, and the results indicate that the dynamic stiffness of the primary mirror supporting type is also improved.

  4. Motor-Auditory-Visual Integration: The Role of the Human Mirror Neuron System in Communication and Communication Disorders

    ERIC Educational Resources Information Center

    Le Bel, Ronald M.; Pineda, Jaime A.; Sharma, Anu

    2009-01-01

    The mirror neuron system (MNS) is a trimodal system composed of neuronal populations that respond to motor, visual, and auditory stimulation, such as when an action is performed, observed, heard or read about. In humans, the MNS has been identified using neuroimaging techniques (such as fMRI and mu suppression in the EEG). It reflects an…

  5. Formation of subwavelength grating on molybdenum mirrors using a femtosecond Ti:sapphire laser system operating at 10 Hz.

    PubMed

    Sharma, Avnish Kumar; Smedley, John; Tsang, Thomas; Rao, Triveni

    2011-03-01

    We report formation of subwavelength surface grating over large surface area of molybdenum mirror by multiple irradiation of amplified femtosecond laser pulses from a homemade Ti:sapphire oscillator-amplifier laser system in a raster scan configuration. The laser system delivered 2 mJ, 80 fs duration laser pulses at a pulse repetition rate of 10 Hz. Various parameters such as pulse fluence, number of pulses, laser polarization, scan speed, and scan steps were optimized to obtain uniform subwavelength gratings. Energy dispersive x-ray spectroscopy measurements were conducted to analyze the elemental composition of mirror surfaces before and after laser treatment.

  6. Ferrofluid based deformable mirrors: a new approach to adaptive optics using liquid mirrors

    NASA Astrophysics Data System (ADS)

    Laird, Phil R.; Bergamasco, R.; Bérubé, Vincent; Borra, Ermanno F.; Gingras, Julie; Ritcey, Anna-Marie R.; Rioux, Myriam; Robitaille, Nathalie; Thibault, Simon; Vieira da Silva, L., Jr.; Yockell-Lelièvre, Helene

    2003-02-01

    The trend towards ever larger telescopes and more advanced adaptive optics systems is driving the need for deformable mirrors with a large number of low cost actuators. Liquid mirrors have long been recognized a potential low cost alternative to conventional solid mirrors. By using a water or oil based ferrofluid we are able to benefit from a stronger magnetic response than is found in magnetic liquid metal amalgams and avoid the difficulty of passing a uniform current through a liquid. Depositing a thin silver colloid known as a metal liquid like film (MELLF) on the ferrofluid surface solves the problem of low reflectivity of pure ferrofluids. This combination provides a liquid optical surface that can be precisely shaped in a magnetic field. We present experimental results obtained with a prototype deformable liquid mirror based on this combination.

  7. ADVANCED POWER SYSTEMS ANALYSIS TOOLS

    SciTech Connect

    Robert R. Jensen; Steven A. Benson; Jason D. Laumb

    2001-08-31

    The use of Energy and Environmental Research Center (EERC) modeling tools and improved analytical methods has provided key information in optimizing advanced power system design and operating conditions for efficiency, producing minimal air pollutant emissions and utilizing a wide range of fossil fuel properties. This project was divided into four tasks: the demonstration of the ash transformation model, upgrading spreadsheet tools, enhancements to analytical capabilities using the scanning electron microscopy (SEM), and improvements to the slag viscosity model. The ash transformation model, Atran, was used to predict the size and composition of ash particles, which has a major impact on the fate of the combustion system. To optimize Atran key factors such as mineral fragmentation and coalescence, the heterogeneous and homogeneous interaction of the organically associated elements must be considered as they are applied to the operating conditions. The resulting model's ash composition compares favorably to measured results. Enhancements to existing EERC spreadsheet application included upgrading interactive spreadsheets to calculate the thermodynamic properties for fuels, reactants, products, and steam with Newton Raphson algorithms to perform calculations on mass, energy, and elemental balances, isentropic expansion of steam, and gasifier equilibrium conditions. Derivative calculations can be performed to estimate fuel heating values, adiabatic flame temperatures, emission factors, comparative fuel costs, and per-unit carbon taxes from fuel analyses. Using state-of-the-art computer-controlled scanning electron microscopes and associated microanalysis systems, a method to determine viscosity using the incorporation of grey-scale binning acquired by the SEM image was developed. The image analysis capabilities of a backscattered electron image can be subdivided into various grey-scale ranges that can be analyzed separately. Since the grey scale's intensity is

  8. Advanced Overfire Air system and design

    SciTech Connect

    Gene berkau

    2004-07-30

    The objective of the proposed project is to design, install and optimize a prototype advanced tangential OFA air system on two mass feed stoker boilers that can burn coal, biomass and a mixture of these fuels. The results will be used to develop a generalized methodology for retrofit designs and optimization of advanced OFA air systems. The advanced OFA system will reduce particulate and NOx emissions and improve overall efficiency by reducing carbon in the ash and excess oxygen. The advanced OFA will also provide capabilities for carrying full load and improved load following and transitional operations.

  9. Advanced Chemical Propulsion System Study

    NASA Technical Reports Server (NTRS)

    Portz, Ron; Alexander, Leslie; Chapman, Jack; England, Chris; Henderson, Scott; Krismer, David; Lu, Frank; Wilson, Kim; Miller, Scott

    2007-01-01

    A detailed; mission-level systems study has been performed to show the benefit resulting from engine performance gains that will result from NASA's In-Space Propulsion ROSS Cycle 3A NRA, Advanced Chemical Technology sub-topic. The technology development roadmap to accomplish the NRA goals are also detailed in this paper. NASA-Marshall and NASA-JPL have conducted mission-level studies to define engine requirements, operating conditions, and interfaces. Five reference missions have been chosen for this analysis based on scientific interest, current launch vehicle capability and trends in space craft size: a) GTO to GEO, 4800 kg, delta-V for GEO insertion only approx.1830 m/s; b) Titan Orbiter with aerocapture, 6620 kg, total delta V approx.210 m/s, mostly for periapsis raise after aerocapture; c) Enceladus Orbiter (Titan aerocapture) 6620 kg, delta V approx.2400 m/s; d) Europa Orbiter, 2170 kg, total delta V approx.2600 m/s; and e) Mars Orbiter, 2250 kg, total delta V approx.1860 m/s. The figures of merit used to define the benefit of increased propulsion efficiency at the spacecraft level include propulsion subsystem wet mass, volume and overall cost. The objective of the NRA is to increase the specific impulse of pressure-fed earth storable bipropellant rocket engines to greater than 330 seconds with nitrogen tetroxide and monomothylhydrazine propellants and greater than 335 , seconds with nitrogen tetroxide and hydrazine. Achievement of the NRA goals will significantly benefit NASA interplanetary missions and other government and commercial opportunities by enabling reduced launch weight and/or increased payload. The study also constitutes a crucial stepping stone to future development, such as pump-fed storable engines.

  10. Control of the unilluminated deformable mirror actuators in an altitude-conjugated adaptive optics system

    PubMed

    Veran

    2000-07-01

    Off-axis observations made with adaptive optics are severely limited by anisoplanatism errors. However, conjugating the deformable mirror to an optimal altitude can reduce these errors; it is then necessary to control, through extrapolation, actuators that are not measured by the wave-front sensor (unilluminated actuators). In this study various common extrapolation schemes are investigated, and an optimal method that achieves a significantly better performance is proposed. This extrapolation method involves a simple matrix multiplication and will be implemented in ALTAIR, the Gemini North Telescope adaptive optics system located on Mauna Kea, Hawaii. With this optimal method, the relative H-band Strehl reduction due to extrapolation errors is only 5%, 16%, and 30% when the angular distance between the guide source and the science target is 20, 40 and 60 arc sec, respectively. For a site such as Mauna Kea, these errors are largely outweighed by the increase in the size of the isoplanatic field.

  11. Control of the unilluminated deformable mirror actuators in an altitude-conjugated adaptive optics system

    PubMed

    Veran

    2000-07-01

    Off-axis observations made with adaptive optics are severely limited by anisoplanatism errors. However, conjugating the deformable mirror to an optimal altitude can reduce these errors; it is then necessary to control, through extrapolation, actuators that are not measured by the wave-front sensor (unilluminated actuators). In this study various common extrapolation schemes are investigated, and an optimal method that achieves a significantly better performance is proposed. This extrapolation method involves a simple matrix multiplication and will be implemented in ALTAIR, the Gemini North Telescope adaptive optics system located on Mauna Kea, Hawaii. With this optimal method, the relative H-band Strehl reduction due to extrapolation errors is only 5%, 16%, and 30% when the angular distance between the guide source and the science target is 20, 40 and 60 arc sec, respectively. For a site such as Mauna Kea, these errors are largely outweighed by the increase in the size of the isoplanatic field. PMID:10883986

  12. High dispersive mirrors for erbium-doped fiber chirped pulse amplification system.

    PubMed

    Chen, Yu; Wang, Yanzhi; Wang, Linjun; Zhu, Meiping; Qi, Hongji; Shao, Jianda; Huang, Xiaojun; Yang, Sheng; Li, Chao; Zhou, Kainan; Zhu, Qihua

    2016-08-22

    We report on the development of near-infrared high dispersive mirrors (HDM) with a group delay dispersion (GDD) of -2000 fs2. A HDM pair based on one optimized result at two reference wavelengths (1550 nm and 1560 nm) can reduce the total oscillation of the GDD effectively in the wavelength range of 1530-1575 nm. This HDM pair is designed and fabricated in a single coating run by means of the nonuniformity in film deposition. For the first time, near-infrared HDMs with two different reference wavelengths have been successfully applied in an erbium-doped fiber chirped pulse amplification system for the compression of 4.73 ps laser pulses to 380 fs. PMID:27557259

  13. High dispersive mirrors for erbium-doped fiber chirped pulse amplification system.

    PubMed

    Chen, Yu; Wang, Yanzhi; Wang, Linjun; Zhu, Meiping; Qi, Hongji; Shao, Jianda; Huang, Xiaojun; Yang, Sheng; Li, Chao; Zhou, Kainan; Zhu, Qihua

    2016-08-22

    We report on the development of near-infrared high dispersive mirrors (HDM) with a group delay dispersion (GDD) of -2000 fs2. A HDM pair based on one optimized result at two reference wavelengths (1550 nm and 1560 nm) can reduce the total oscillation of the GDD effectively in the wavelength range of 1530-1575 nm. This HDM pair is designed and fabricated in a single coating run by means of the nonuniformity in film deposition. For the first time, near-infrared HDMs with two different reference wavelengths have been successfully applied in an erbium-doped fiber chirped pulse amplification system for the compression of 4.73 ps laser pulses to 380 fs.

  14. Improved system calibration for specular surface measurement by using reflections from a plane mirror.

    PubMed

    Zhou, Tian; Chen, Kun; Wei, Haoyun; Li, Yan

    2016-09-01

    In this paper, we introduce a flexible and simple system calibration method for specular surface metrology based on the combination of reflection rays determined by the varied points on a screen and reflection images of a plane mirror without fiducials placed at three different locations. This calibration procedure involves three steps. The camera is first calibrated based on plane patterns. Then the reflection ray directions are measured via correspondence matching. The last calibration step is the pose estimation by the orthogonal iteration algorithm and reflections in a plane mirror. Basically, the concept of replacing the coordinates of the camera center with the reflection ray can alleviate the trouble of imaging aberration. Then global optimization can be operated with the orthogonal projection defined by the reflection ray, providing precise initial values for the process of bundle adjustment, compared to the classical calibration approach directly using the local optimization algorithm. Simulations and experiments both demonstrate the validity, efficiency, and robustness of the proposed improved method. In the simulations, the proposed method achieves the absolute errors of the camera parameters within 3 pixels and the relative errors of the screen pose are below 0.5% when the noise level is 0.6 pixel. Furthermore, the calibration method shows strong anti-noise ability, relying on the application of the reflection rays and the global optimization before the final bundle adjustment. In addition, the reconstruction accuracy in our experiment improves by 60.11% by the proposed method compared with the calibration procedure, which only utilizes the bundle adjustment optimization. In general, this novel calibration method can make the measurement achieve high accuracy and robustness at a low cost and with a simple setup, providing an efficient, economical, and flexible approach for a phase measuring deflectometry system in practical situations. PMID:27607278

  15. Dynamic visuomotor transformation involved with remote flying of a plane utilizes the 'Mirror Neuron' system.

    PubMed

    Callan, Daniel E; Gamez, Mario; Cassel, Daniel B; Terzibas, Cengiz; Callan, Akiko; Kawato, Mitsuo; Sato, Masa-aki

    2012-01-01

    Brain regions involved with processing dynamic visuomotor representational transformation are investigated using fMRI. The perceptual-motor task involved flying (or observing) a plane through a simulated Red Bull Air Race course in first person and third person chase perspective. The third person perspective is akin to remote operation of a vehicle. The ability for humans to remotely operate vehicles likely has its roots in neural processes related to imitation in which visuomotor transformation is necessary to interpret the action goals in an egocentric manner suitable for execution. In this experiment for 3(rd) person perspective the visuomotor transformation is dynamically changing in accordance to the orientation of the plane. It was predicted that 3(rd) person remote flying, over 1(st), would utilize brain regions composing the 'Mirror Neuron' system that is thought to be intimately involved with imitation for both execution and observation tasks. Consistent with this prediction differential brain activity was present for 3(rd) person over 1(st) person perspectives for both execution and observation tasks in left ventral premotor cortex, right dorsal premotor cortex, and inferior parietal lobule bilaterally (Mirror Neuron System) (Behaviorally: 1(st)>3(rd)). These regions additionally showed greater activity for flying (execution) over watching (observation) conditions. Even though visual and motor aspects of the tasks were controlled for, differential activity was also found in brain regions involved with tool use, motion perception, and body perspective including left cerebellum, temporo-occipital regions, lateral occipital cortex, medial temporal region, and extrastriate body area. This experiment successfully demonstrates that a complex perceptual motor real-world task can be utilized to investigate visuomotor processing. This approach (Aviation Cerebral Experimental Sciences ACES) focusing on direct application to lab and field is in contrast to standard

  16. Conception and design of a control and monitoring system for the mirror alignment of the CBM RICH detector

    NASA Astrophysics Data System (ADS)

    Bendarouach, J.

    2016-08-01

    The Compressed Baryonic Matter (CBM) experiment at the future Facility for Anti-proton and Ion Research (FAIR) complex will investigate the phase diagram of strongly interacting matter at high baryon density and moderate temperatures created in A+A collisions. For the SIS100 accelerator, the foreseen beam energy will range up to 11 AGeV for the heaviest nuclei. One of the key detector components required for the CBM physics program is the Ring Imaging CHerenkov (RICH) detector, which is developed for efficient and clean electron identification and pion suppression. An important aspect to guarantee a stable operation of the RICH detector is the alignment of the mirrors. A qualitative alignment control procedure for the mirror system has been implemented in the CBM RICH prototype detector and tested under real conditions at the CERN PS/T9 beamline. Collected data and results of image processing are reviewed and discussed. In parallel a quantitative method using recorded data has also been employed to compute mirror displacements of the RICH mirrors. Results based on simulated events and the limits of the method are presented and discussed as well. If mirror misalignment is detected, it can be subsequently included and rectified by correction routines. A first correction routine is presented and a comparison between misaligned, corrected and ideal geometries is shown.

  17. Point Relay Scanner Utilizing Ellipsoidal Mirrors

    NASA Technical Reports Server (NTRS)

    Manhart, Paul K. (Inventor); Pagano, Robert J. (Inventor)

    1997-01-01

    A scanning system uses a polygonal mirror assembly with each facet of the polygon having an ellipsoidal mirror located thereon. One focal point of each ellipsoidal mirror is located at a common point on the axis of rotation of the polygonal mirror assembly. As the mirror assembly rotates. a second focal point of the ellipsoidal mirrors traces out a scan line. The scanner can be utilized for scanned output display of information or for scanning information to be detected.

  18. The Athena Mirror

    NASA Astrophysics Data System (ADS)

    Wille, Eric

    2016-07-01

    The Athena mission (Advanced Telescope for High Energy Astrophysics) requires lightweight X-ray Wolter optics with a high angular resolution and large effective area. For achieving an effective area of 2 m^2 (at 1 keV) and an angular resolution of below 5 arcsec, the Silicon Pore Optics technology was developed by ESA together with a consortium of European industry. Silicon Pore Optics are made of commercial Si wafers using process technology adapted from the semiconductor industry. We present the current design of the Athena mirror concentrating on the technology development status of the Silicon Pore Optics, ranging from the manufacturing of single mirror plates towards complete focusing mirror modules and their integration into the mirror structure.

  19. Mirror image proteins.

    PubMed

    Zhao, Le; Lu, Wuyuan

    2014-10-01

    Proteins composed entirely of unnatural d-amino acids and the achiral amino acid glycine are mirror image forms of their native l-protein counterparts. Recent advances in chemical protein synthesis afford unique and facile synthetic access to domain-sized mirror image d-proteins, enabling protein research to be conducted through 'the looking glass' and in a way previously unattainable. d-Proteins can facilitate structure determination of their native l-forms that are difficult to crystallize (racemic X-ray crystallography); d-proteins can serve as the bait for library screening to ultimately yield pharmacologically superior d-peptide/d-protein therapeutics (mirror-image phage display); d-proteins can also be used as a powerful mechanistic tool for probing molecular events in biology. This review examines recent progress in the application of mirror image proteins to structural biology, drug discovery, and immunology.

  20. The design of an active support control system for a thin 1.2m primary mirror

    NASA Astrophysics Data System (ADS)

    Liu, Rong; Li, Xiaojin; Liu, Haitao; Wang, Hongqiao

    2014-09-01

    Active support system is a low-frequency wavefront error correction system, which is often used to correct the mirror deformation resulting from gravity, temperature, wind load, manufacture, installation and other factors. In addition, the active support technology can improve the efficiency of grinding and polishing by adjusting the surface shape in the process of manufacturing large mirrors. This article describes the design of an active support control system for a thin 1.2m primary mirror. The support system consists of 37 axial pneumatic actuators. And in order to change the shape of thin primary mirror we need to precisely control the 37 pneumatic actuators. These 37 pneumatic actuators are divided into six regions. Each region is designed with a control circuit board to realize force closed-loop control for the pneumatic actuators, and all control panels are connected to the PC by CAN bus. The control panels have to support: receive commands from the host PC; control the actuators; periodically return result of control. The whole control system is composed by hardware and control algorithm and communication program.

  1. Design of three-mirror illumination system with free-form fly's eye for extreme ultraviolet lithography.

    PubMed

    Mei, Qiuli; Li, Yanqiu

    2015-03-10

    The low source power is one of the major challenges that hinder the extreme ultraviolet lithography from high volume manufacturing. To alleviate the source development pressure, a high-efficiency illumination system with three mirrors is proposed, based on the authors' knowledge, for the first time. Free-form fly's eye is introduced into the system to get a qualified arc-shaped irradiance distribution on the reticle. A method integrated with a numerical method and optimization to design the free-form surface is given in detail. The transfer efficiency of the system is much higher than that of the four-mirror configuration employed in the EUV exposure platform. Compared with the previous high-efficiency illumination system with two mirrors, this configuration can ensure a good uniformity and will not increase the objective design difficulty or affect the image quality of the objective. Simulation result of the design with three mirrors shows the uniformity on the reticle is about 95.5%, and the energy efficiency is about 25.4%. It indicates that the system is effective in enhancing the efficiency and potential to promote the EUV lithography into high volume manufacturing. PMID:25968388

  2. In-situ surface debris inspection and removal system for upward-facing transport mirrors of the National Ignition Facility

    SciTech Connect

    Gourdin, W H; Dzenitis, E; Martin, D; Listiyo, K; Sherman, G; Kent, W; Butlin, R; Stolz, C J; Pryatel, J

    2004-11-10

    We describe a system to inspect and remove surface debris in-situ from the surfaces of upward-facing mirrors that transport 1053 nm laser light to the target chamber of the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory. Grazing angle (2-5{sup o}) illumination with a bar light highlights debris {approx}10 {micro}m in size and larger, which is then viewed through windows in the enclosures of selected mirrors. Debris is removed with 1-second bursts of high velocity (76 m/s) clean air delivered across the optic surfaces by a commercially available linear nozzle (''gas knife''). Experiments with aluminum, stainless steel, glass and polystyrene particles of various sizes >30 {micro}m show that particle removal efficiency is near 100% over most of the mirror surfaces for all sizes tested.

  3. COMPONENTS OF LASER SYSTEMS AND STABILITY PROBLEMS: Diffraction calculation of the field in a composite three-mirror unstable resonator

    NASA Astrophysics Data System (ADS)

    Elkin, N. N.; Korotkov, V. A.; Napartovich, A. P.; Troshchiev, V. E.

    1988-08-01

    A numerical investigation is made of a two-dimensional model of a composite unstable resonator with three mirrors. The relevant parabolic equations are solved using a three-layer scheme and a fast Fourier transformation algorithm. A strong dependence of the distribution of the intensity of the output wave and of the distribution of the radiation in the far-field zone on the displacement of a reference mirror over distances of the order of one wavelength provides an opportunity for the control of optical characteristics of a system.

  4. Detection of single gold nanoparticles using spatial modulation spectroscopy implemented with a galvo-scanning mirror system.

    PubMed

    Devadas, Mary Sajini; Li, Zhongming; Major, Todd A; Lo, Shun Shang; Havard, Nicolas; Yu, Kuai; Johns, Paul; Hartland, Gregory V

    2013-11-10

    The optical extinction of single nanoparticles can be sensitively detected by spatial modulation spectroscopy (SMS), where the particle is moved in and out of a tightly focused laser beam with a piezo-device. Here we show that high sensitivity can be obtained by modulating the beam with a galvo-mirror system, rather than by moving the sample. This work demonstrates an inexpensive method for making a SMS microscope, and shows how an existing laser scanning microscope can be adapted for SMS measurements. The galvo-mirror technique also allows SMS measurements to be performed in a liquid, which is difficult to do with piezo-modulation.

  5. Diamond Turned High Precision PIAA Optics and Four Mirror PIAA System for High Contrast Imaging of Exo-planets

    NASA Technical Reports Server (NTRS)

    Balasubramanian, Kunjithapatham; Cady, Eric; Pueyo, Laurent; Ana, Xin; Shaklan, Stuart; Guyon, Olivier; Belikov, Ruslan

    2011-01-01

    Off-axis, high-sag PIAA optics for high contrast imaging present challenges in manufacturing and testing. With smaller form factors and consequently smaller surface deformations (< 80 microns), diamond turned fabrication of these mirrors becomes feasible. Though such a design reduces the system throughput, it still provides 2(lambda)D inner working angle. We report on the design, fabrication, measurements, and initial assessment of the novel PIAA optics in a coronagraph testbed. We also describe, for the first time, a four mirror PIAA coronagraph that relaxes apodizer requirements and significantly improves throughput while preserving the low-cost benefits.

  6. Calculus of bands and profiles of study the system mirror - resonance of the Fibonacci Pt/Zn

    NASA Astrophysics Data System (ADS)

    Castro-Arce, Lamberto; Figueroa-Navarro, Carlos; Campos-Garcia, Julio; Molinar-Tabares, Martin; Ramos-Mendieta, Felipe; Manzanares-Martinez, Betzabe

    2015-03-01

    In order to analyze the behavior of a mirror - located resonance of 2pi, in a given system and with a given filling factor equal to 0.4 a study has been realized in an arrangement fibonacci, also in periodic slabs jobs. It is observed how in a study of profile that some waves are annulled giving birth to the mirror placed in 2pi. With regard to the resonance in a profile study the maxima are in certain structure Pt Pt Zn Pt Pt. Even if we increase the number of repetitions these are preserved, that means that they are related to effects of segments isolated inside the multilayer.

  7. COMPONENTS OF LASER SYSTEMS AND STABILITY PROBLEMS: Residual infrared absorption in metal mirrors

    NASA Astrophysics Data System (ADS)

    Vinogradov, Aleksandr V.; Tolstikhin, O. I.

    1988-08-01

    An analysis is made of the physical factors that limit the reflectivity of mirrors in the infrared range. It is shown that the mechanism responsible for the finite residual absorption is the electron-phonon interaction in the presence of a photon (Holstein-Gurzhi effect). A study is also made of the influence of the surface roughness on the absorptivity of mirrors.

  8. Mirror mount

    DOEpatents

    Kuklo, T.C.; Bender, D.A.

    1994-10-04

    A unique lens or mirror mount having adjustable constraints at two key locations to allow for ''X'' and ''Y'' tilts of the mirror only is disclosed. The device uses two pair of flexures of a type such that the pivots of the mirror gimble are rigidly fixed in all planes allowing the device to have zero stacking tolerance and zero wear over time. 4 figs.

  9. A novel photovoltaic power system which uses a large area concentrator mirror

    NASA Technical Reports Server (NTRS)

    Arrison, Anne; Fatemi, Navid

    1987-01-01

    A preliminary analysis has been made of a novel photovoltaic power system concept. The system is composed of a small area, dense photovoltaic array, a large area solar concentrator, and a battery system for energy storage. The feasibility of such a system is assessed for space power applications. The orbital efficiency, specific power, mass, and area of the system are calculated under various conditions and compared with those for the organic Rankine cycle solar dynamic system proposed for Space Station. Near term and advanced large area concentrator photovoltaic systems not only compare favorably to solar dynamic systems in terms of performance but offer other benefits as well.

  10. Dysfunction of the Human Mirror Neuron System in Ideomotor Apraxia: Evidence from Mu Suppression.

    PubMed

    Frenkel-Toledo, Silvi; Liebermann, Dario G; Bentin, Shlomo; Soroker, Nachum

    2016-06-01

    Stroke patients with ideomotor apraxia (IMA) have difficulties controlling voluntary motor actions, as clearly seen when asked to imitate simple gestures performed by the examiner. Despite extensive research, the neurophysiological mechanisms underlying failure to imitate gestures in IMA remain controversial. The aim of the current study was to explore the relationship between imitation failure in IMA and mirror neuron system (MNS) functioning. Mirror neurons were found to play a crucial role in movement imitation and in imitation-based motor learning. Their recruitment during movement observation and execution is signaled in EEG recordings by suppression of the lower (8-10 Hz) mu range. We examined the modulation of EEG in this range in stroke patients with left (n = 21) and right (n = 15) hemisphere damage during observation of video clips showing different manual movements. IMA severity was assessed by the DeRenzi standardized diagnostic test. Results showed that failure to imitate observed manual movements correlated with diminished mu suppression in patients with damage to the right inferior parietal lobule and in patients with damage to the right inferior frontal gyrus pars opercularis-areas where major components of the human MNS are assumed to reside. Voxel-based lesion symptom mapping revealed a significant impact on imitation capacity for the left inferior and superior parietal lobules and the left post central gyrus. Both left and right hemisphere damages were associated with imitation failure typical of IMA, yet a clear demonstration of relationship to the MNS was obtained only in the right hemisphere damage group. Suppression of the 8-10 Hz range was stronger in central compared with occipital sites, pointing to a dominant implication of mu rather than alpha rhythms. However, the suppression correlated with De Renzi's apraxia test scores not only in central but also in occipital sites, suggesting a multifactorial mechanism for IMA, with a possible

  11. Design Of A Support System For The Primary Mirror Of A Cryogenic Space Telescope

    NASA Astrophysics Data System (ADS)

    DiTolla, Robert; Richard, Ralph M.; Vukobratovich, Daniel

    1986-07-01

    The finite element method was used for the structural design of the Space Infrared Telescope Facility (SIRTF) primary mirror and its support system in a cryogenic environment similar to space-shuttle cargo-bay launch conditions. Shuttle loads were specified by power spectral density functions (PSDF) obtained from previous shuttle launches. The primary goal in the development of a design to withstand this random loading was to ensure the structural integrity of the support system, which comprised an aluminum baseplate and three titanium flexures. This design was an extension of a support system previously developed for cryogenic static effects only. The displacements and stresses of the support system are greatly affected by the damping characteristics of the flexures, which are very difficult to quantify. A parametric study illustrates the behavior of the system over the range of the estimated damping values. Recommendations and techniques for modeling this type of structure are presented. The methods and approaches used in the analysis and the effect of model refinement upon solution accuracy are discussed.

  12. Imitation and Action Understanding in Autistic Spectrum Disorders: How Valid Is the Hypothesis of a Deficit in the Mirror Neuron System?

    ERIC Educational Resources Information Center

    Hamilton, Antonia F. de C.; Brindley, Rachel M.; Frith, Uta

    2007-01-01

    The motor mirror neuron system supports imitation and goal understanding in typical adults. Recently, it has been proposed that a deficit in this mirror neuron system might contribute to poor imitation performance in children with autistic spectrum disorders (ASD) and might be a cause of poor social abilities in these children. We aimed to test…

  13. Reduced mu suppression and altered motor resonance in euthymic bipolar disorder: Evidence for a dysfunctional mirror system?

    PubMed

    Andrews, Sophie C; Enticott, Peter G; Hoy, Kate E; Thomson, Richard H; Fitzgerald, Paul B

    2016-01-01

    Social cognitive difficulties are common in the acute phase of bipolar disorder and, to a lesser extent, during the euthymic stage, and imaging studies of social cognition in euthymic bipolar disorder have implicated mirror system brain regions. This study aimed to use a novel multimodal approach (i.e., including both transcranial magnetic stimulation (TMS) and electroencephalogram (EEG)) to investigate mirror systems in bipolar disorder. Fifteen individuals with euthymic bipolar disorder and 16 healthy controls participated in this study. Single-pulse TMS was applied to the optimal site in the primary motor cortex (M1), which stimulates the muscle of interest during the observation of hand movements (goal-directed or interacting) designed to elicit mirror system activity. Single EEG electrodes (C3, CZ, C4) recorded mu rhythm modulation concurrently. Results revealed that the patient group showed significantly less mu suppression compared to healthy controls. Surprisingly, motor resonance was not significantly different overall between groups; however, bipolar disorder participants showed a pattern of reduced reactivity on some conditions. Although preliminary, this study indicates a potential mirror system deficit in euthymic bipolar disorder, which may contribute to the pathophysiology of the disorder. PMID:25763634

  14. Corticospinal mirror neurons.

    PubMed

    Kraskov, A; Philipp, R; Waldert, S; Vigneswaran, G; Quallo, M M; Lemon, R N

    2014-01-01

    Here, we report the properties of neurons with mirror-like characteristics that were identified as pyramidal tract neurons (PTNs) and recorded in the ventral premotor cortex (area F5) and primary motor cortex (M1) of three macaque monkeys. We analysed the neurons' discharge while the monkeys performed active grasp of either food or an object, and also while they observed an experimenter carrying out a similar range of grasps. A considerable proportion of tested PTNs showed clear mirror-like properties (52% F5 and 58% M1). Some PTNs exhibited 'classical' mirror neuron properties, increasing activity for both execution and observation, while others decreased their discharge during observation ('suppression mirror-neurons'). These experiments not only demonstrate the existence of PTNs as mirror neurons in M1, but also reveal some interesting differences between M1 and F5 mirror PTNs. Although observation-related changes in the discharge of PTNs must reach the spinal cord and will include some direct projections to motoneurons supplying grasping muscles, there was no EMG activity in these muscles during action observation. We suggest that the mirror neuron system is involved in the withholding of unwanted movement during action observation. Mirror neurons are differentially recruited in the behaviour that switches rapidly between making your own movements and observing those of others.

  15. How mirror-touch informs theories of synesthesia.

    PubMed

    Meier, Beat; Lunke, Katrin; Rothen, Nicolas

    2015-01-01

    Ward and Banissy provide an excellent overview of the state of mirror-touch research in order to advance this field. They present a comparison of two prominent theoretical approaches for understanding mirror-touch phenomena. According to the threshold theory, the phenomena arise as a result of a hyperactive mirror neuron system. According to the Self-Other Theory, they are due to disturbances in the ability to distinguish the self from others. Here, we explore how these two theories can inform theories of synesthesia more generally. We conclude that both theories are not suited as general models of synesthesia.

  16. How mirror-touch informs theories of synesthesia.

    PubMed

    Meier, Beat; Lunke, Katrin; Rothen, Nicolas

    2015-01-01

    Ward and Banissy provide an excellent overview of the state of mirror-touch research in order to advance this field. They present a comparison of two prominent theoretical approaches for understanding mirror-touch phenomena. According to the threshold theory, the phenomena arise as a result of a hyperactive mirror neuron system. According to the Self-Other Theory, they are due to disturbances in the ability to distinguish the self from others. Here, we explore how these two theories can inform theories of synesthesia more generally. We conclude that both theories are not suited as general models of synesthesia. PMID:26118388

  17. Advanced Vehicle system concepts. [nonpetroleum passenger transportation

    NASA Technical Reports Server (NTRS)

    Hardy, K. S.; Langendoen, J. M.

    1983-01-01

    Various nonpetroleum vehicle system concepts for passenger vehicles in the 1990's are being considered as part of the Advanced Vehicle (AV) Assessment at the Jet Propulsion Laboratory. The vehicle system and subsystem performance requirements, the projected characteristics of mature subsystem candidates, and promising systems are presented. The system candidates include electric and hybrid vehicles powered by electricity with or without a nonpetroleum power source. The subsystem candidates include batteries (aqueous-mobile, flow, high-temperature, and metal-air), fuel cells (phosphoric acid, advanced acids, and solid polymer electrolyte), nonpetroleum heat engines, advanced dc and ac propulsion components, power-peaking devices, and transmissions.

  18. Advanced Group Support Systems and Facilities

    NASA Technical Reports Server (NTRS)

    Noor, Ahmed K. (Compiler); Malone, John B. (Compiler)

    1999-01-01

    The document contains the proceedings of the Workshop on Advanced Group Support Systems and Facilities held at NASA Langley Research Center, Hampton, Virginia, July 19-20, 1999. The workshop was jointly sponsored by the University of Virginia Center for Advanced Computational Technology and NASA. Workshop attendees came from NASA, other government agencies, industry, and universities. The objectives of the workshop were to assess the status of advanced group support systems and to identify the potential of these systems for use in future collaborative distributed design and synthesis environments. The presentations covered the current status and effectiveness of different group support systems.

  19. MEMS scanner mirror based system for retina scanning and in eye projection

    NASA Astrophysics Data System (ADS)

    Woittennek, Franziska; Knobbe, Jens; Pügner, Tino; Dallmann, Hans-Georg; Schelinski, Uwe; Grüger, Heinrich

    2015-02-01

    Many applications could benefit from miniaturized systems to scan blood vessels behind the retina in the human eye, so called "retina scanning". This reaches from access control to sophisticated security applications and medical devices. High volume systems for consumer applications require low cost and a user friendly operation. For example this includes no need for removal of glasses and self-adjustment, in turn guidance of focus and point of attraction by simultaneous projection for the user. A new system has been designed based on the well-known resonantly driven 2-d scanner mirror of Fraunhofer IPMS. A combined NIR and VIS laser system illuminates the eye through an eye piece designed for an operating distance allowing the use of glasses and granting sufficient field of view. This usability feature was considered to be more important than highest miniaturization. The modulated VIS laser facilitates the projection of an image directly onto the retina. The backscattered light from the continuous NIR laser contains the information of the blood vessels and is detected by a highly sensitive photo diode. A demonstrational setup has been realized including readout and driving electronics. The laser power was adjusted to an eye-secure level. Additional security features were integrated. Test measurements revealed promising results. In a first demonstration application the detection of biometric pattern of the blood vessels was evaluated for issues authentication in.

  20. Active control of adaptive optics system in a large segmented mirror telescope

    NASA Astrophysics Data System (ADS)

    Nagashima, M.; Agrawal, B. N.

    2014-02-01

    For a large adaptive optics system such as a large segmented mirror telescope (SMT), it is often difficult, although not impossible, to directly apply common multi-input multi-output (MIMO) controller design methods due to the computational burden imposed by the large dimension of the system model. In this article, a practical controller design method is proposed which significantly reduces the system dimension for a system where the dimension required to represent the dynamics of the plant is much smaller than the dimension of the full plant model. The proposed method decouples the dynamic and static parts of the plant model by a modal decomposition technique to separately design a controller for each part. Two controllers are then combined using the so-called sensitivity decoupling method so that the resulting feedback loop becomes the superposition of the two individual feedback loops of the dynamic and static parts. A MIMO controller was designed by the proposed method using the H ∞ loop-shaping technique for an SMT model to be compared with other controllers proposed in the literature. Frequency-domain analysis and time-domain simulation results show the superior performance of the proposed controller.

  1. Design and implementation of a beam-waveguide mirror control system for vernier pointing of the DSS-13 antenna

    NASA Technical Reports Server (NTRS)

    Alvarez, L. S.; Moore, M.; Veruttipong, W.; Andres, E.

    1994-01-01

    The design and implementation of an antenna beam-waveguide (BWG) mirror position control system at the DSS-13 34-m antenna is presented. While it has several potential applications, a positioner on the last flat-plate BWG mirror (M6) at DSS 13 is installed to demonstrate the conical scan (conscan) angle-tracking technique at the Ka-band (32-GHz) operating frequency. Radio frequency (RF) beam-scanning predictions for the M6 mirror, computed from a diffraction analysis, are presented. From these predictions, position control system requirements are then derived. The final mechanical positioner and servo system designs, as implemented at DSS 13, are illustrated with detailed design descriptions given in the appendices. Preliminary measurements of antenna Ka-band beam scan versus M6 mirror tilt made at DSS 13 in December 1993 are presented. After reduction, the initial measurements are shown to be in agreement with the RF predicts. Plans for preliminary conscan experimentation at DSS 13 are summarized.

  2. Assurance Technology Challenges of Advanced Space Systems

    NASA Technical Reports Server (NTRS)

    Chern, E. James

    2004-01-01

    The initiative to explore space and extend a human presence across our solar system to revisit the moon and Mars post enormous technological challenges to the nation's space agency and aerospace industry. Key areas of technology development needs to enable the endeavor include advanced materials, structures and mechanisms; micro/nano sensors and detectors; power generation, storage and management; advanced thermal and cryogenic control; guidance, navigation and control; command and data handling; advanced propulsion; advanced communication; on-board processing; advanced information technology systems; modular and reconfigurable systems; precision formation flying; solar sails; distributed observing systems; space robotics; and etc. Quality assurance concerns such as functional performance, structural integrity, radiation tolerance, health monitoring, diagnosis, maintenance, calibration, and initialization can affect the performance of systems and subsystems. It is thus imperative to employ innovative nondestructive evaluation methodologies to ensure quality and integrity of advanced space systems. Advancements in integrated multi-functional sensor systems, autonomous inspection approaches, distributed embedded sensors, roaming inspectors, and shape adaptive sensors are sought. Concepts in computational models for signal processing and data interpretation to establish quantitative characterization and event determination are also of interest. Prospective evaluation technologies include ultrasonics, laser ultrasonics, optics and fiber optics, shearography, video optics and metrology, thermography, electromagnetics, acoustic emission, x-ray, data management, biomimetics, and nano-scale sensing approaches for structural health monitoring.

  3. Magic Mirrors

    ERIC Educational Resources Information Center

    Mills, Allan

    2011-01-01

    "Magic mirrors" were so named because, when they were positioned to throw a reflected patch of sunlight on a nearby wall, this area contained an outline of a design cast on the back of the (bronze) mirror. Investigations begun in the 19th century showed that this was a response to heavy localized pressures exerted on the face of the thin mirror…

  4. Slumped mirrors

    NASA Astrophysics Data System (ADS)

    Pteancu, Mircea; Dragan, Dorin; Dragan, Olivier; Miron, Andrei; Stanescu, Octavian

    2008-02-01

    The authors discusse the construction of slumped mirrors, their fabrication and testing (polishing and lapping). An important topic of the discussion is thermal fabrication of mirrors by using of matrixes. One of the authors of the entry is combining astronomy and aquariums construction.

  5. Simple system of aberration correction for very large spherical primary mirrors

    NASA Astrophysics Data System (ADS)

    Beach, David A.

    2000-10-01

    Several large telescopes are now being proposed that would benefit from the cost reduction due to the use of spherical primary mirror. However, structural cost constraints require compact formats that tend to impose very high speeds, e.g. f/1.5, which renders difficult the correction of the resulting very large spherical aberration. A technique is described here in which a spherical concentric Cassegrain-like primary-secondary combination is followed by a simple catadioptric focal modifier. The spherical primary is 9m diameter, f/1.5, and the final focus is f/5 with a sub-arcsecond resolution over a 5 arcminute angular field for a passband of 480-850nm. Primary- secondary separation is only 11m and central obscuration is only 11% of pupil area. The two relatively small corrector components provide the functions of concentric meniscus and zonal corrector plate and are made from the same single glass- BK7 is the example given, but silica or any other preferred glass is possible. The relatively small zonal corrector is the only aspheric surface in the entire system. A related system is described elsewhere in which a 30 arcminute angular field can be achieved with a similar resolution, but with more complex glass requirements. However, supply of such exotic glasses may be difficult in large diameters, and the system presented here may find a place in some specialized applications.

  6. Spectroradiometric considerations for advanced land observing systems

    NASA Technical Reports Server (NTRS)

    Slater, P. N.

    1986-01-01

    Research aimed at improving the inflight absolute radiometric calibration of advanced land observing systems was initiated. Emphasis was on the satellite sensor calibration program at White Sands. Topics addressed include: absolute radiometric calibration of advanced remote sensing; atmospheric effects on reflected radiation; inflight radiometric calibration; field radiometric methods for reflectance and atmospheric measurement; and calibration of field relectance radiometers.

  7. The design for off-axis multimirror optical system with large field and small F number using coaxial assembly of two mirrors

    NASA Astrophysics Data System (ADS)

    Liu, Hui; Yan, Shi-qiang; Pei, Yun-tian; Hu, Lei; Xu, Song

    2012-09-01

    The reflection optical system gets more and more attention nowadays owing to without chromatic aberration and small volume. The manufacturing and assembly/calibration technology for the coaxial reflection optical system is more mature relative to the other reflection optical systems. But the coaxial reflection optical system will obstruct the incidence ray especially when the field is large, which will reduce the energy entering the optical system and reduce the resolution. The off-axis Three-Mirror Optical Systems can conquer those disadvantages of the coaxial reflection optical system, however the manufacturing and assembly/calibration for the off-axis Optical Systems is very difficult which must use computer-aided technology. The manufacturing and assembly/calibration technology is the main bottleneck for the off-axis Optical Systems to the engineering application. The Author of this thesis researched the design theory of the Three-Mirror Optical System, and then schemed out off-axis Three-Mirror and Multi-Mirror Optical System smartly using coaxial two-mirror optical structure which conquers the disadvantage of small field and possesses of the all advantages of the coaxial reflection optical system. This new optical system has two mirrors, one of which is a parabolic mirror with high-order aspheric term and the other is a hyperboloid mirror with high-order aspheric term. The characteristics of this new optical system are as follows: the F Number is 1.25, the field of view is 2°×2° and the total length is only 115mm with coaxial assembly of the two mirrors.

  8. Cosmology with liquid mirror telescopes

    NASA Astrophysics Data System (ADS)

    Hogg, David W.; Gibson, Brad K.; Hickson, Paul

    1993-01-01

    Liquid mirrors provide an exciting means to obtain large optical telescopes for substantially lower costs than conventional technologies. The liquid mirror concept has been demonstrated in the lab with the construction of a diffraction limited 1.5 m mirror. The mirror surface, using liquid mercury, forms a perfect parabolic shape when the mirror cell is rotated at a uniform velocity. A liquid mirror must be able to support a heavy mercury load with minimal flexure and have a fundamental resonant frequency that is as high as possible, to suppress the amplitude of surface waves caused by small vibrations transmitted to the mirror. To minimize the transmission of vibrations to the liquid surface, the entire mirror rests on an air bearing. This necessitates the mirror cell being lightweight, due to the limited load capabilities of the air bearing. The mirror components must also have physical characteristics which minimize the effects of thermal expansion with ambient temperature fluctuations in the observatory. In addition, the 2.7 m mirror construction is designed so that the techniques used may be readily extended to the construction of large mirrors. To attain the goals of a lightweight, rigid mirror, a composite laminant construction was used. The mirror consists of a foam core cut to the desired parabolic shape, with an accuracy of a few mm. An aluminum hub serves as an anchor for the foam and skin, and allows precise centering of the mirror on the air bearing and drive system. Several plys of Kevlar, covered in an epoxy matrix, are then applied to the foam. A final layer of pure epoxy is formed by spin casting. This final layer is parabolic to within a fraction of a mm. An aluminum ring bonded to the circumference of the mirror retains the mercury, and incorporates stainless-steel hard-points for the attachment of balance weights.

  9. Mechanical principles of large mirror supports

    NASA Astrophysics Data System (ADS)

    Kärcher, Hans J.; Eisenträger, Peter; Süss, Martin

    2010-07-01

    Large thin meniscus mirrors use force-controlled shape actuators to obtain the required optical performance. The shape actuators can be interpreted as an advancement of classical mirror supports as whiffle trees or iso-static levers, which worked purely mechanical. The paper develops, after a short historical overview, the theoretical background of mirror mechanics. Different combinations of force-controlled shape actuators with mechanical, hydraulic or pneumatic whiffle trees or iso-static levers are analyzed in regard of their impact on optical performance, dynamic and control behavior. The investigations were the basis for the choice of the shape actuator system for the E-ELT M2, executed by MT Mechatronics under an ESO contract in 2008-09.

  10. From music making to speaking: engaging the mirror neuron system in autism.

    PubMed

    Wan, Catherine Y; Demaine, Krystal; Zipse, Lauryn; Norton, Andrea; Schlaug, Gottfried

    2010-05-31

    Individuals with autism show impairments in emotional tuning, social interactions and communication. These are functions that have been attributed to the putative human mirror neuron system (MNS), which contains neurons that respond to the actions of self and others. It has been proposed that a dysfunction of that system underlies some of the characteristics of autism. Here, we review behavioral and imaging studies that implicate the MNS (or a brain network with similar functions) in sensory-motor integration and speech representation, and review data supporting the hypothesis that MNS activity could be abnormal in autism. In addition, we propose that an intervention designed to engage brain regions that overlap with the MNS may have significant clinical potential. We argue that this engagement could be achieved through forms of music making. Music making with others (e.g., playing instruments or singing) is a multi-modal activity that has been shown to engage brain regions that largely overlap with the human MNS. Furthermore, many children with autism thoroughly enjoy participating in musical activities. Such activities may enhance their ability to focus and interact with others, thereby fostering the development of communication and social skills. Thus, interventions incorporating methods of music making may offer a promising approach for facilitating expressive language in otherwise nonverbal children with autism.

  11. Slit-mounted LED fiducial system for rotating mirror streak cameras

    SciTech Connect

    Shaw, L.L.; Muelder, S.A.; Rivera, A.T.

    1991-01-01

    We have developed a fiducial system for rotating mirror streak cameras that utilizes light emitting diodes mounted at the slit position of the camera. The diodes are driven to the required high brightness by a unique pulse power circuit designed to provide high voltage, high current pulses 18 nanoseconds in length at a frequency of up to 2.5 megahertz. The availability of super bright light emitting diodes with a wavelength of 630 to 640 nanometers allows us to record fiducial pulses, at streaking speeds in excess of 20mm per microsecond, on all the black and white films commonly used in high speed photography. The time marks on the film record are referenced to the real time of the experiment from a clock-driver that controls the start and frequency of the fiducial pulse train and by three adjustable and discreet blanked fiducials. This paper discusses the development of this system and describes the full setup as used at LLNL. 6 refs., 4 figs.

  12. Anatomical differences in the mirror neuron system and social cognition network in autism.

    PubMed

    Hadjikhani, Nouchine; Joseph, Robert M; Snyder, Josh; Tager-Flusberg, Helen

    2006-09-01

    Autism spectrum disorder (ASD) is a neurodevelopmental disorder associated with impaired social and emotional skills, the anatomical substrate of which is still unknown. In this study, we compared a group of 14 high-functioning ASD adults with a group of controls matched for sex, age, intelligence quotient, and handedness. We used an automated technique of analysis that accurately measures the thickness of the cerebral cortex and generates cross-subject statistics in a coordinate system based on cortical anatomy. We found local decreases of gray matter in the ASD group in areas belonging to the mirror neuron system (MNS), argued to be the basis of empathic behavior. Cortical thinning of the MNS was correlated with ASD symptom severity. Cortical thinning was also observed in areas involved in emotion recognition and social cognition. These findings suggest that the social and emotional deficits characteristic of autism may reflect abnormal thinning of the MNS and the broader network of cortical areas subserving social cognition. PMID:16306324

  13. Autism, emotion recognition and the mirror neuron system: the case of music.

    PubMed

    Molnar-Szakacs, Istvan; Wang, Martha J; Laugeson, Elizabeth A; Overy, Katie; Wu, Wai-Ling; Piggot, Judith

    2009-01-01

    Understanding emotions is fundamental to our ability to navigate and thrive in a complex world of human social interaction. Individuals with Autism Spectrum Disorders (ASD) are known to experience difficulties with the communication and understanding of emotion, such as the nonverbal expression of emotion and the interpretation of emotions of others from facial expressions and body language. These deficits often lead to loneliness and isolation from peers, and social withdrawal from the environment in general. In the case of music however, there is evidence to suggest that individuals with ASD do not have difficulties recognizing simple emotions. In addition, individuals with ASD have been found to show normal and even superior abilities with specific aspects of music processing, and often show strong preferences towards music. It is possible these varying abilities with different types of expressive communication may be related to a neural system referred to as the mirror neuron system (MNS), which has been proposed as deficient in individuals with autism. Music's power to stimulate emotions and intensify our social experiences might activate the MNS in individuals with ASD, and thus provide a neural foundation for music as an effective therapeutic tool. In this review, we present literature on the ontogeny of emotion processing in typical development and in individuals with ASD, with a focus on the case of music. PMID:21264050

  14. Autism, Emotion Recognition and the Mirror Neuron System: The Case of Music

    PubMed Central

    Molnar-Szakacs, Istvan; Wang, Martha J.; Laugeson, Elizabeth A.; Overy, Katie; Wu, Wai-Ling; Piggot, Judith

    2009-01-01

    Understanding emotions is fundamental to our ability to navigate and thrive in a complex world of human social interaction. Individuals with Autism Spectrum Disorders (ASD) are known to experience difficulties with the communication and understanding of emotion, such as the nonverbal expression of emotion and the interpretation of emotions of others from facial expressions and body language. These deficits often lead to loneliness and isolation from peers, and social withdrawal from the environment in general. In the case of music however, there is evidence to suggest that individuals with ASD do not have difficulties recognizing simple emotions. In addition, individuals with ASD have been found to show normal and even superior abilities with specific aspects of music processing, and often show strong preferences towards music. It is possible these varying abilities with different types of expressive communication may be related to a neural system referred to as the mirror neuron system (MNS), which has been proposed as deficient in individuals with autism. Music’s power to stimulate emotions and intensify our social experiences might activate the MNS in individuals with ASD, and thus provide a neural foundation for music as an effective therapeutic tool. In this review, we present literature on the ontogeny of emotion processing in typical development and in individuals with ASD, with a focus on the case of music. PMID:21264050

  15. Design of axisymmetric multi-mirror grazing incidence system to increase the numerical aperture of neutron and X-ray microscopes

    NASA Astrophysics Data System (ADS)

    Aoki, Sadao; Watanabe, Norio; Asami, Hiroshi; Shimada, Akihiro

    2016-04-01

    An axisymmetric multi-mirror system for neutron and X-ray microscopes is proposed to increase their numerical aperture and collection efficiency. A Wolter type-I mirror is used as the basis of the multi-mirror system at grazing incidence. The addition of an even number of hyperboloid mirrors to the Wolter type-I mirror can satisfy both an equal optical path length and Abbe's sine condition. The numerical aperture increases in proportion to the number of mirrors. The optical parameters of the system with four tandem mirrors are calculated for neutrons and X-rays with a wavelength of 0.4 nm by assuming that the average grazing angle of incidence is 5.4 mrad and the magnification is 10. The inner diameters of the mirrors are limited to <10 mm considering the total length of the optical system. Tolerance of off-axis distance was calculated using a ray-tracing computer simulation. Ray tracing shows that a blur size <14 nm will be possible at an off-axis displacement of 10 μm.

  16. Optimizing Advanced Power System Designs Under Uncertainty

    SciTech Connect

    Rubin, E.S.; Diwekar; Frey, H.C.

    1996-12-31

    This paper describes recent developments in ongoing research to develop and demonstrate advanced computer-based methods for dealing with uncertainties that are critical to the design of advanced coal-based power systems. Recent developments include new deterministic and stochastic methods for simulation, optimization, and synthesis of advanced process designs. Results are presented illustrating the use of these new modeling tools for the design and analysis of several advanced systems of current interest to the U.S. Department of Energy, including the technologies of integrated gasification combined cycle (IGCC), advanced pressurized fluid combustion (PFBC), and the externally fired combined cycle (EFCC) process. The new methods developed in this research can be applied generally to any chemical or energy conversion process to reduce the technological risks associated with uncertainties in process performance and cost.

  17. Micromachining technology for advanced weapon systems

    SciTech Connect

    Sniegowski, J.J.

    1996-12-31

    An overview of planned uses for polysilicon surface-micromachining technology in advanced weapon systems is presented. Specifically, this technology may allow consideration of fundamentally new architectures for realization of surety component functions.

  18. Mirror, Mirror on the Wall...?

    ERIC Educational Resources Information Center

    Pflaster, Gail

    1979-01-01

    The study determined the value of using a mirror for speech teaching by recording manner, place, voicing, and blend errors produced by 27 hearing-impaired children (5-13 years old) while imitating consonant-vowel syllables under three conditions (audition alone, audition plus direct vision, and audition plus vision using a mirror). (Author)

  19. Engine health monitoring: An advanced system

    NASA Technical Reports Server (NTRS)

    Dyson, R. J. E.

    1981-01-01

    The advanced propulsion monitoring system is described. The system was developed in order to fulfill a growing need for effective engine health monitoring. This need is generated by military requirements for increased performance and efficiency in more complex propulsion systems, while maintaining or improving the cost to operate. This program represents a vital technological step in the advancement of the state of the art for monitoring systems in terms of reliability, flexibility, accuracy, and provision of user oriented results. It draws heavily on the technology and control theory developed for modern, complex, electronically controlled engines and utilizes engine information which is a by-product of such a system.

  20. Nonelastomeric Rod Seals for Advanced Hydraulic Systems

    NASA Technical Reports Server (NTRS)

    Hady, W. F.; Waterman, A. W.

    1976-01-01

    Advanced high temperature hydraulic system rod sealing requirements can be met by using seals made of nonelastomeric (plastic) materials in applications where elastomers do not have adequate life. Exploratory seal designs were optimized for advanced applications using machinable polyimide materials. These seals demonstrated equivalent flight hour lives of 12,500 at 350 F and 9,875 at 400 F in advanced hydraulic system simulation. Successful operation was also attained under simulated space shuttle applications; 96 reentry thermal cycles and 1,438 hours of vacuum storage. Tests of less expensive molded plastic seals indicated a need for improved materials to provide equivalent performance to the machined seals.

  1. Granularity within the mirror system is not informative on action perception. Comment on "Grasping synergies: A motor-control approach to the mirror neuron mechanism" by D'Ausilio et al.

    NASA Astrophysics Data System (ADS)

    Cattaneo, Luigi

    2015-03-01

    The present work [1] reviews a part of the now vast literature on visuomotor stimulus-response associations in the domain of action observation, commonly referred to as mirror mechanism or mirror system. The aim of the study is to propose a solution to a currently debated problem, namely in what frame of reference are mirror neurons coding movement. The solution proposed here is that, if the mirror system is part of the motor system, then the motor responses to action observation must be in the same frames of reference as that generally observed in the production of voluntary actions. This idea is part of the very first conceptualizations of the mirror system ("Each time an individual sees an action done by another individual, neurons that represent that action are activated in the observer's premotor cortex. This automatically induced, motor representation of the observed action corresponds to that which is spontaneously generated during active action and whose outcome is known to the acting individual" [2]) and has been explicitly proposed earlier [3] in the attempt of reconciling the very different findings in the literature on the mirror system's frames of reference. The novelty of the present approach is the explicit reference to the 'motor synergy' theory of voluntary hand movements. This theory states that the high number of degrees of freedom intrinsic to hand anatomy is reduced by the motor system to few principal components named motor synergies that are the building blocks of voluntary behavior [4]. I am enthusiastic about two points proposed by D'Ausilio in the present review and I am skeptical about some other points.

  2. Multichannel analog-to-digital converters based on current mirrors for the optical systems

    NASA Astrophysics Data System (ADS)

    Krasilenko, Vladimir G.; Nikolskyy, A. I.; Nikolska, M. A.; Lobodzinska, R. F.

    2011-12-01

    The paper considers results of designing and modeling analogue-digital converters (ADC) based on current mirrors for the optical systems and neural networks with parallel inputs-outputs. Such ADC, named us multichannel analog-todigital converters based on current mirrors (M ADC CM). Compared with usual converters, for example, reading, a bitby- bit equilibration, and so forth, have a number of advantages: high speed and reliability, simplicity, small power consumption, the big degree of integration in linear and matrix structures. The considered aspects of designing of M_ADC CM in binary codes. Base digit cells (ABC) of such M_ADC CM, series-pipelined are connected in structures, consist from 20-30 CMOS the transistors, one photodiode, have low (1,5-3,5) supply voltage, work in current modes with the maximum values of currents (10-40)μA. Therefore such new principles of realization high-speed low-discharge M_ADC CM have allowed, as have shown modeling experiments, to reach time of transformation less than 20-30 nS at 5-6 bits of a binary code and the general power 1-5 mW. The quantity easily cascadable ABC depends on wordlength ADC, and makes n, and provides quantity of levels of quantization equal N=2n. Such simple enough on structure M ADC CM, having low power consumption <= 3 ÷ 5mW, supply voltage (3-7)V, is provided at the same time with good dynamic characteristics (frequency of digitization even for 1,5μm or 0,35 μm- CMOS-technologies has made 40 MHz, and can be increased 10 times) and accuracy (Δquantization 156,25nA for I max10μA) characteristics is show. The range can be transformed optical signals, taking into account sensitivity of modern photodetectors makes 20-200 μW in such ADC. M_ADC CM open new prospects for realization linear and matrix (with picture operands) micro photoelectronic structures which are necessary for neural networks, digital optoelectronic processors, neurofuzzy controllers, and so forth.

  3. Mu suppression - A good measure of the human mirror neuron system?

    PubMed

    Hobson, Hannah M; Bishop, Dorothy V M

    2016-09-01

    Mu suppression has been proposed as a signature of the activity of the human mirror neuron system (MNS). However the mu frequency band (8-13 Hz) overlaps with the alpha frequency band, which is sensitive to attentional fluctuation, and thus mu suppression could potentially be confounded by changes in attentional engagement. The specific baseline against which mu suppression is assessed may be crucial, yet there is little consistency in how this is defined. We examined mu suppression in 61 typical adults, the largest mu suppression study so far conducted. We compared different methods of baselining, and examined activity at central and occipital electrodes, to both biological (hands) and non-biological (kaleidoscope) moving stimuli, to investigate the involvement of attention and alpha activity in mu suppression. We also examined changes in beta power, another candidate index of MNS engagement. We observed strong mu suppression restricted to central electrodes when participants performed hand movements, demonstrating that mu is indeed responsive to the activity of the motor cortex. However, when we looked for a similar signature of mu suppression to passively observed stimuli, the baselining method proved to be crucial. Selective suppression for biological versus non-biological stimuli was seen at central electrodes only when we used a within-trial baseline based on a static stimulus: this method greatly reduced trial-by-trial variation in the suppression measure compared with baselines based on blank trials presented in separate blocks. Even in this optimal condition, 16-21% of participants showed no mu suppression. Changes in beta power also did not match our predicted pattern for MNS engagement, and did not seem to offer a better measure than mu. Our conclusions are in contrast to those of a recent meta-analysis, which concluded that mu suppression is a valid means to examine mirror neuron activity. We argue that mu suppression can be used to index the human MNS

  4. Advanced air revitalization system testing

    NASA Technical Reports Server (NTRS)

    Heppner, D. B.; Hallick, T. M.; Schubert, F. H.

    1983-01-01

    A previously developed experimental air revitalization system was tested cyclically and parametrically. One-button startup without manual interventions; extension by 1350 hours of tests with the system; capability for varying process air carbon dioxide partial pressure and humidity and coolant source for simulation of realistic space vehicle interfaces; dynamic system performance response on the interaction of the electrochemical depolarized carbon dioxide concentrator, the Sabatier carbon dioxide reduction subsystem, and the static feed water electrolysis oxygen generation subsystem, the carbon dioxide concentrator module with unitized core technology for the liquid cooled cell; and a preliminary design for a regenerative air revitalization system for the space station are discussed.

  5. Fused silica mirror development for SIRTF

    NASA Technical Reports Server (NTRS)

    Barnes, W. P., Jr.

    1983-01-01

    An advanced design, lightweight, fuse-quartz mirror of sandwich construction was evaluated for optical figure performance at cryogenic temperatures. A low temperature shroud was constructed with an integral mirror mount and interface to a cryostat for use in a vacuum chamber. The mirror was tested to 13 K. Cryogenic distortion of the mirror was measured interferometrically. Separate interferometry of the chamber window during the test permitted subtraction of the small window distortions from the data. Results indicate that the imaging performance of helium cooled, infrared telescopes will be improved using this type of mirror without correction of cryogenic distortion of the primary mirror.

  6. Advanced EVA system design requirements study

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Design requirements and criteria for the Space Station Advanced Extravehicular Activity System (EVAS) including crew enclosures, portable life support systems, maneuvering propulsion systems, and related extravehicular activity (EVA) support equipment were defined and established. The EVA mission requirements, environments, and medical and physiological requirements, as well as opertional, procedures, and training issues were considered.

  7. Hybrid and Electric Advanced Vehicle Systems Simulation

    NASA Technical Reports Server (NTRS)

    Beach, R. F.; Hammond, R. A.; Mcgehee, R. K.

    1985-01-01

    Predefined components connected to represent wide variety of propulsion systems. Hybrid and Electric Advanced Vehicle System (HEAVY) computer program is flexible tool for evaluating performance and cost of electric and hybrid vehicle propulsion systems. Allows designer to quickly, conveniently, and economically predict performance of proposed drive train.

  8. Characterization of advanced electric propulsion systems

    NASA Technical Reports Server (NTRS)

    Ray, P. K.

    1982-01-01

    Characteristic parameters of several advanced electric propulsion systems are evaluated and compared. The propulsion systems studied are mass driver, rail gun, argon MPD thruster, hydrogen free radical thruster and mercury electron bombardment ion engine. Overall, ion engines have somewhat better characteristics as compared to the other electric propulsion systems.

  9. On the optimal reconstruction and control of adaptive optical systems with mirror dynamics.

    PubMed

    Correia, Carlos; Raynaud, Henri-François; Kulcsár, Caroline; Conan, Jean-Marc

    2010-02-01

    In adaptive optics (AO) the deformable mirror (DM) dynamics are usually neglected because, in general, the DM can be considered infinitely fast. Such assumption may no longer apply for the upcoming Extremely Large Telescopes (ELTs) with DM that are several meters in diameter with slow and/or resonant responses. For such systems an important challenge is to design an optimal regulator minimizing the variance of the residual phase. In this contribution, the general optimal minimum-variance (MV) solution to the full dynamical reconstruction and control problem of AO systems (AOSs) is established. It can be looked upon as the parent solution from which simpler (used hitherto) suboptimal solutions can be derived as special cases. These include either partial DM-dynamics-free solutions or solutions derived from the static minimum-variance reconstruction (where both atmospheric disturbance and DM dynamics are neglected altogether). Based on a continuous stochastic model of the disturbance, a state-space approach is developed that yields a fully optimal MV solution in the form of a discrete-time linear-quadratic-Gaussian (LQG) regulator design. From this LQG standpoint, the control-oriented state-space model allows one to (1) derive the optimal state-feedback linear regulator and (2) evaluate the performance of both the optimal and the sub-optimal solutions. Performance results are given for weakly damped second-order oscillatory DMs with large-amplitude resonant responses, in conditions representative of an ELT AO system. The highly energetic optical disturbance caused on the tip/tilt (TT) modes by the wind buffeting is considered. Results show that resonant responses are correctly handled with the MV regulator developed here. The use of sub-optimal regulators results in prohibitive performance losses in terms of residual variance; in addition, the closed-loop system may become unstable for resonant frequencies in the range of interest. PMID:20126246

  10. Design and simulation of the active support system for a 1.2m meniscus primary mirror

    NASA Astrophysics Data System (ADS)

    Liu, Haitao; Fan, Bin; Zeng, Zhige; Li, Xiaojin; Wang, Hongqiao; Liu, Rong

    2015-07-01

    Thin meniscus primary mirrors with active support have been used successfully in many large telescopes, and also draw attention of many optical fabricators. Because the active support system can correct the low order figure errors, such as astigmatism, coma, trefoil 3rd astigmatism, the optical fabricators can just focus on to remove high order figure errors. This will shorten the fabrication time. In this paper, we present an active support system for a 1.2m meniscus parabolic primary mirror. It contains 37 axial push-pull force supports, 3 axial fixed points, and 4 lateral restraints. Some basic performance of the active support system is analyzed and the figure error correction capability is also studied based on Zernike modes.

  11. The plasticity of the mirror system: How reward learning modulates cortical motor simulation of others

    PubMed Central

    Trilla Gros, Irene; Panasiti, Maria Serena; Chakrabarti, Bhismadev

    2015-01-01

    Cortical motor simulation supports the understanding of others' actions and intentions. This mechanism is thought to rely on the mirror neuron system (MNS), a brain network that is active both during action execution and observation. Indirect evidence suggests that (alpha/beta) mu suppression, an electroencephalographic (EEG) index of MNS activity, is modulated by reward. In this study we aimed to test the plasticity of the MNS by directly investigating the link between (alpha/beta) mu suppression and reward. 40 individuals from a general population sample took part in an evaluative conditioning experiment, where different neutral faces were associated with high or low reward values. In the test phase, EEG was recorded while participants viewed videoclips of happy expressions made by the conditioned faces. Alpha/beta mu suppression (identified using event-related desynchronisation of specific independent components) in response to rewarding faces was found to be greater than for non-rewarding faces. This result provides a mechanistic insight into the plasticity of the MNS and, more generally, into the role of reward in modulating physiological responses linked to empathy. PMID:25744871

  12. Modulation in the mirror neuron system when action prediction is not satisfied.

    PubMed

    Plata Bello, Julio; Modroño, Cristián; Marcano, Francisco; González-Mora, José Luis

    2015-04-01

    The ability to understand competitive games is closely connected to the mirror neuron system (MNS). This network is activated not only when an action is performed, but also when it is observed. Apart from allowing the understanding of actions performed by others, the MNS has been implicated in predicting subsequent actions. However, the results concerning the modulation of this network by the final outcome of these predictions are contradictory. These contradictions may be related to the use of complex experimental conditions. The aim of this research is to identify changes in the activity of the MNS when the predictions are or are not satisfied in a simple intransitive action-based game. An event-related functional magnetic resonance imaging study was conducted. It consisted of the observation of videos with two actors playing the well-known rock-paper-scissors game. The participants were asked to predict the response of the second actor when the first actor performed one of the three possible actions. In some videos (congruents) the prediction was satisfied, but in the rest of the videos (incongruents) the prediction was not satisfied. When the result was shown, higher activity in the MNS was observed in the congruent videos than in the incongruent ones. Therefore, the observation of a simple manual game leads to a significant activation of the MNS, and this activity seems to be modulated by the final outcome of a prediction, and when predictions are satisfied the activity is higher.

  13. Development of procedures to ensure quality and integrity in Tandem Mirror Experiment-Upgrade (TMX-U) diagnostics systems

    SciTech Connect

    Coutts, G.W.; Coon, M.L.; Hinz, A.F.; Hornady, R.S.; Lang, D.D.; Lund, N.P.

    1983-11-30

    The diagnostic systems for Tandem Mirror Experiment-Upgrade (TMX-U) have grown from eleven initial systems to more than twenty systems. During operation, diagnostic system modifications are sometimes required to complete experimental objectives. Also, during operations new diagnostic systems are being developed and implemented. To ensure and maintain the quality and integrity of the data signals, a set of plans and systematic actions are being developed. This paper reviews the procedures set in place to maintain the integrity of existing data systems and ensure the performance objectives of new diagnostics being added.

  14. Advances in rotorcraft system identification

    NASA Astrophysics Data System (ADS)

    Hamel, Peter G.; Kaletka, Jürgen

    1997-03-01

    System identification can best be described as the extraction of system characteristics from measured flight test data. Therefore it provides an excellent tool for determining and improving mathematical models for a wide range of applications. The increasing need for accurate models for the design of high bandwidth control systems for rotorcraft has initiated a high interest in and a more intensive use of system identification. This development was supported by the AGARD FVP Working Group 18 on ‘Rotorcraft System Identification’, which brought together specialists from research organisations and industry, tasked with exploring the potential of this tool. In the Group, the full range of identification approaches was applied to dedicated helicopter flight-test-data including data quality checking and the determination and verification of flight mechanical models. It was mainly concentrated on the identification of six degrees of freedom rigid body models, which provide a realistic description of the rotorcraft dynamics for the lower and medium frequency range. The accomplishment of the Working Group has increased the demand for applying these techniques more routinely and, in addition, for extending the model order by including explicit rotor degrees of freedom. Such models also accurately characterize the higher frequency range needed for high bandwidth control system designs. In the specific case of the DLR In-Flight Simulator BO 105 ATTHeS, the application of the identified higher order models for the model-following control system was a major prerequisite for the obtained high simulation quality.

  15. Optical design and characterization of an advanced computational imaging system

    NASA Astrophysics Data System (ADS)

    Shepard, R. Hamilton; Fernandez-Cull, Christy; Raskar, Ramesh; Shi, Boxin; Barsi, Christopher; Zhao, Hang

    2014-09-01

    We describe an advanced computational imaging system with an optical architecture that enables simultaneous and dynamic pupil-plane and image-plane coding accommodating several task-specific applications. We assess the optical requirement trades associated with custom and commercial-off-the-shelf (COTS) optics and converge on the development of two low-cost and robust COTS testbeds. The first is a coded-aperture programmable pixel imager employing a digital micromirror device (DMD) for image plane per-pixel oversampling and spatial super-resolution experiments. The second is a simultaneous pupil-encoded and time-encoded imager employing a DMD for pupil apodization or a deformable mirror for wavefront coding experiments. These two testbeds are built to leverage two MIT Lincoln Laboratory focal plane arrays - an orthogonal transfer CCD with non-uniform pixel sampling and on-chip dithering and a digital readout integrated circuit (DROIC) with advanced on-chip per-pixel processing capabilities. This paper discusses the derivation of optical component requirements, optical design metrics, and performance analyses for the two testbeds built.

  16. US Advanced Freight and Passenger MAGLEV System

    NASA Technical Reports Server (NTRS)

    Morena, John J.; Danby, Gordon; Powell, James

    1996-01-01

    Japan and Germany will operate first generation Maglev passenger systems commercially shortly after 2000 A.D. The United States Maglev systems will require sophisticated freight and passenger carrying capability. The U.S. freight market is larger than passenger transport. A proposed advanced freight and passenger Maglev Project in Brevard County Florida is described. Present Maglev systems cost 30 million dollars or more per mile. Described is an advanced third generation Maglev system with technology improvements that will result in a cost of 10 million dollars per mile.

  17. Demonstration Advanced Avionics System (DAAS)

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The feasibility of developing an integrated avionics system suitable for general aviation was determined. A design of reliable integrated avionics which provides expanded functional capability that significantly enhances the utility and safety of general aviation at a cost commensurate with the general aviation market was developed. The use of a data bus, microprocessors, electronic displays and data entry devices, and improved function capabilities were emphasized. An avionics system capable of evaluating the most critical and promising elements of an integrated system was designed, built and flight tested in a twin engine general aviation aircraft.

  18. Mirror mount

    DOEpatents

    Humpal, Harold H.

    1987-01-01

    A mirror mount (10) is provided that allows free pitch, yaw and roll motion of the mirror (28) while keeping the location of a point (56) on the surface of the mirror (28) fixed in the rest frame of reference of the mount (10). Yaw movement is provided by two yaw cylinders (30,32) that are bearing (52) mounted to provide rotation. Pitch and roll motion is provided by a spherically annular shell (42) that is air bearing (72,74) mounted to move between a clamp (60) and an upper pedestal bearing (44). The centers of curvature of the spherical surfaces of the shell (42) lie upon the point (56). Pitch motion and roll motion are separately and independently imparted to mirror (28) by a pair of pitch paddles (34) and a pair of roll paddles (36) that are independently and separately moved by control rods (76,80) driven by motors (78,82).

  19. Mirror mount

    DOEpatents

    Humpal, H.H.

    1986-03-21

    A mirror mount is provided that allows free pitch, yaw and roll motion of the mirror while keeping the location of a point on the surface of the mirror fixed in the rest frame of reference of the mount. Yaw movement is provided by two yaw cylinders that are bearing mounted to provide rotation. Pitch and roll motion is provided by a spherically annular shell that is air bearing mounted to move between a clamp and an upper pedestal bearing. The centers of curvature of the spherical surfaces of the shell lie upon the point. Pitch motion and roll motion are separately and independently imparted to mirror by a pair of pitch paddles and a pair of roll paddles that are independently and separately moved by control rods driven by motors.

  20. Mirror mount

    DOEpatents

    Humpal, H.H.

    1987-11-10

    A mirror mount is provided that allows free pitch, yaw and roll motion of the mirror while keeping the location of a point on the surface of the mirror fixed in the rest frame of reference of the mount. Yaw movement is provided by two yaw cylinders that are bearing mounted to provide rotation. Pitch and roll motion is provided by a spherically annular shell that is air bearing mounted to move between a clamp and an upper pedestal bearing. The centers of curvature of the spherical surfaces of the shell lie upon the point. Pitch motion and roll motion are separately and independently imparted to mirror by a pair of pitch paddles and a pair of roll paddles that are independently and separately moved by control rods driven by motors. 5 figs.

  1. Remote counseling using HyperMirror quasi space-sharing system

    NASA Astrophysics Data System (ADS)

    Hashimoto, Sayuri; Morikawa, Osamu; Hashimoto, Nobuyuki; Maesako, Takanori

    2008-08-01

    In the modern information society, networks are getting faster, costs are getting lower, and displays are getting clearer. Today, just about anyone can easily use precise, dynamic, image distribution systems in their everyday life. Now, the question is how to give the benefits of network systems to the local community, as well as to each individual.This study was designed to use communication with realistic sensations to examine the effectiveness of remote individual counseling intervention in reducing depression, anxiety and stress in child-rearing mothers. Three child-rearing mothers residing in the city of Osaka each received one session of remote counseling intervention. The results showed an alleviation of stress related to child-rearing, i.e., the reduction in state anxiety, depression and subjective stress related to child-rearing. Moreover, an experimental demonstration employed a HyperMirror system capable of presenting visual and auditory images similar to reality, in order to provide the counselees with realistic sensations. While the voice communication environment was poor, the remote counseling allowed for the communication of sensory information, i.e., skinship that communicated information related to assurance/peace of mind, and auditory information, i.e., a whispering voices in which signals of affection were transmitted; the realistic sensation contributed to a reduction in stress levels. The positive effects of the intervention were confirmed through a pre and post intervention study. The results suggested the need to conduct future studies to confirm the mid- and long-term improvements caused by the intervention, as well as the need to improve the voice transmission environment.

  2. Deformable mirrors based on magnetic liquids

    NASA Astrophysics Data System (ADS)

    Laird, Phil R.; Borra, Ermanno F.; Bergamasco, Rosangela; Gingras, Julie; Truong, Long; Ritcey, Anna

    2004-10-01

    The trend towards ever larger telescopes and more advanced adaptive optics systems such as multi-conjugate adaptive optics is driving the need for deformable mirrors with a large number of low cost actuators. Other applications require strokes larger than those readily available from conventional mirrors. Magnetically deformable liquid mirrors are a potential solution to both these problems. Depositing a thin silver colloid known as a metal liquid-like film (MELLF) on the ferrofluid surface solves the problem of low reflectivity of pure ferrofluids. This combination provides a liquid optical surface that can be precisely shaped in a magnetic field. We have demonstrated a reflective coating that is stable for more than 30 days with a reflectivity of 50% in the near infrared. Additional experiments indicate that MELLF coatings can provide near infrared reflectivity values in excess of 80%. We also report on recent response time measurements of liquid deformable mirrors. We have demonstrated liquid mirror actuators with slew rates of 800 μm/s, corresponding to an actuator bandwidth of approximately 40 Hz and 80 Hz for strokes of 10 μm and 5 μm respectively.

  3. Advanced Sensor Systems for Biotelemetry

    NASA Technical Reports Server (NTRS)

    Hines, John W. (Inventor); Somps, Christopher J. (Inventor); Ricks, Robert D. (Inventor); Mundt, Carsten W. (Inventor)

    2003-01-01

    The present invention relates to telemetry-based sensing systems that continuously measures physical, chemical and biological parameters. More specifically, these sensing systems comprise a small, modular, low-power implantable biotelemetry system capable of continuously sensing physiological characteristics using implantable transmitters, a receiver, and a data acquisition system to analyze and record the transmitted signal over several months. The preferred embodiment is a preterm labor and fetal monitoring system. Key features of the invention include Pulse Interval Modulation (PIM) that is used to send temperature and pressure information out of the biological environment. The RF carrier frequency is 174-216 MHz and a pair of RF bursts (pulses) is transmitted at a frequency of about 1-2 Hz. The transmission range is 3 to 10 feet, depending on the position of the transmitter in the body and its biological environment. The entire transmitter is encapsulated in biocompatible silicone rubber. Power is supplied by on-board silver-oxide batteries. The average power consumption of the current design is less than 30 microW, which yields a lifetime of approximately 6 - 9 months. Chip-on-Board technology (COB) drastically reduces the size of the printed circuit board from 38 x 28 mm to 22 x 8 mm. Unpackaged dies are flip-chip bonded directly onto the printed circuit board, along with surface mount resistors and capacitors. The invention can monitor additional physiological parameters including, but not limited to, ECG, blood gases, glucose, and ions such as calcium, potassium, and sodium.

  4. Highly efficient end-side-pumped Nd:YAG solar laser by a heliostat-parabolic mirror system.

    PubMed

    Almeida, J; Liang, D; Vistas, C R; Guillot, E

    2015-03-10

    We report a large improvement in the collection and slope efficiency of an Nd:YAG solar laser pumped by a heliostat-parabolic mirror system. A conical fused silica lens was used to further concentrate the solar radiation from the focal zone of a 2 m diameter primary concentrator to a Nd:YAG single-crystal rod within a conical pump cavity, which enabled multipass pumping to the active medium. A 56 W cw laser power was measured, corresponding to 21.1  W/m2 record-high solar laser collection efficiency with the heliostat-parabolic mirror system. 4.9% slope efficiency was calculated, corresponding to 175% enhancement over our previous result. PMID:25968373

  5. Highly efficient end-side-pumped Nd:YAG solar laser by a heliostat-parabolic mirror system.

    PubMed

    Almeida, J; Liang, D; Vistas, C R; Guillot, E

    2015-03-10

    We report a large improvement in the collection and slope efficiency of an Nd:YAG solar laser pumped by a heliostat-parabolic mirror system. A conical fused silica lens was used to further concentrate the solar radiation from the focal zone of a 2 m diameter primary concentrator to a Nd:YAG single-crystal rod within a conical pump cavity, which enabled multipass pumping to the active medium. A 56 W cw laser power was measured, corresponding to 21.1  W/m2 record-high solar laser collection efficiency with the heliostat-parabolic mirror system. 4.9% slope efficiency was calculated, corresponding to 175% enhancement over our previous result.

  6. Modeling Advance Life Support Systems

    NASA Technical Reports Server (NTRS)

    Pitts, Marvin; Sager, John; Loader, Coleen; Drysdale, Alan

    1996-01-01

    Activities this summer consisted of two projects that involved computer simulation of bioregenerative life support systems for space habitats. Students in the Space Life Science Training Program (SLSTP) used the simulation, space station, to learn about relationships between humans, fish, plants, and microorganisms in a closed environment. One student complete a six week project to modify the simulation by converting the microbes from anaerobic to aerobic, and then balancing the simulation's life support system. A detailed computer simulation of a closed lunar station using bioregenerative life support was attempted, but there was not enough known about system restraints and constants in plant growth, bioreactor design for space habitats and food preparation to develop an integrated model with any confidence. Instead of a completed detailed model with broad assumptions concerning the unknown system parameters, a framework for an integrated model was outlined and work begun on plant and bioreactor simulations. The NASA sponsors and the summer Fell were satisfied with the progress made during the 10 weeks, and we have planned future cooperative work.

  7. Advanced sensor systems for biotelemetry

    NASA Technical Reports Server (NTRS)

    Hines, John W. (Inventor); Somps, Christopher J. (Inventor); Ricks, Robert D. (Inventor); Mundt, Carsten W. (Inventor)

    2003-01-01

    The present invention relates to telemetry-based sensing systems that continuously measures physical, chemical and biological parameters. More specifically, these sensing systems comprise a small, modular, low-power implantable biotelemetry system capable of continuously sensing physiological characteristics using implantable transmitters, a receiver, and a data acquisition system to analyze and record the transmitted signal over several months. The preferred embodiment is a preterm labor and fetal monitoring system. Key features of the invention include Pulse Interval Modulation (PIM) that is used to send temperature and pressure information out of the biological environment. The RF carrier frequency is 174-216 MHz and a pair of RF bursts (pulses) is transmitted at a frequency of about 1-2 Hz. The transmission range is 3 to 10 feet, depending on the position of the transmitter in the body and its biological environment. The entire transmitter is encapsulated in biocompatible silicone rubber. Power is supplied by on-board silver-oxide batteries. The average power consumption of the current design is less than 30 .mu.W., which yields a lifetime of approximately 6-9 months. Chip-on-Board technology (COB) drastically reduces the size of the printed circuit board from 38.times.28 mm to 22.times.8 mm. Unpackaged dies are flip-chip bonded directly onto the printed circuit board, along with surface mount resistors and capacitors. The invention can monitor additional physiological parameters including, but not limited to, ECG, blood gases, glucose, and ions such as calcium, potassium, and sodium.

  8. Combustion modeling in advanced gas turbine systems

    SciTech Connect

    Smoot, L.D.; Hedman, P.O.; Fletcher, T.H.; Brewster, B.S.; Kramer, S.K.

    1995-12-31

    Goal of DOE`s Advanced Turbine Systems program is to develop and commercialize ultra-high efficiency, environmentally superior, cost competitive gas turbine systems for base-load applications in utility, independent power producer, and industrial markets. Primary objective of the program here is to develop a comprehensive combustion model for advanced gas turbine combustion systems using natural gas (coal gasification or biomass fuels). The efforts included code evaluation (PCGC-3), coherent anti-Stokes Raman spectroscopy, laser Doppler anemometry, and laser-induced fluorescence.

  9. Improved boost mirror for low-concentration photovoltaic solar power systems

    NASA Astrophysics Data System (ADS)

    Wells, David N.

    2009-08-01

    A new reflector surface and geometry using low-concentration mirror boosting of flat-plate photo voltaic devices is described. The overheating effects that have previously been seen using non-uniform, high reflectivity side mirrors have been reduced. The new high-stability reflector material has lower UV reflectivity that reduces panel ageing and over heating. A moderate reflectivity in the violet wavelength further cuts the level of overheating while sacrificing only minimally in electrical power output efficiency. The new surface maintains high, uniform reflectivity at green, yellow, red, and IR wavelengths. Mass-produced panels are undergoing tests, and some preliminary results are presented. Surface self-cleaning of hydrophilic and hydrophobic coating over the reflecting surface is also discussed. Other applications of the same mirror in the solar thermal field are briefly discussed. Some improved tracking PV geometry versions using the new material are presented.

  10. Westinghouse advanced particle filter system

    SciTech Connect

    Lippert, T.E.; Bruck, G.J.; Sanjana, Z.N.; Newby, R.A.

    1994-10-01

    Integrated Gasification Combined Cycles (IGCC) and Pressurized Fluidized Bed Combustion (PFBC) are being developed and demonstrated for commercial, power generation application. Hot gas particulate filters are key components for the successful implementation of IGCC and PFBC in power generation gas turbine cycles. The objective of this work is to develop and qualify through analysis and testing a practical hot gas ceramic barrier filter system that meets the performance and operational requirements of PFBC and IGCC systems. This paper updates the assessment of the Westinghouse hot gas filter design based on ongoing testing and analysis. Results are summarized from recent computational fluid dynamics modeling of the plenum flow during back pulse, analysis of candle stressing under cleaning and process transient conditions and testing and analysis to evaluate potential flow induced candle vibration.

  11. Advances in Microsphere Insulation Systems

    NASA Astrophysics Data System (ADS)

    Allen, M. S.; Baumgartner, R. G.; Fesmire, J. E.; Augustynowicz, S. D.

    2004-06-01

    Microsphere insulation, typically consisting of hollow glass bubbles, combines in a single material the desirable properties that other insulations only have individually. The material has high crush strength, low density, is noncombustible, and performs well in soft vacuum. Microspheres provide robust, low-maintenance insulation systems for cryogenic transfer lines and dewars. They also do not suffer from compaction problems typical of perlite that result in the necessity to reinsulate dewars because of degraded thermal performance and potential damage to its support system. Since microspheres are load bearing, autonomous insulation panels enveloped with lightweight vacuum-barrier materials can be created. Comprehensive testing performed at the Cryogenics Test Laboratory located at the NASA Kennedy Space Center demonstrated competitive thermal performance with other bulk materials. Test conditions were representative of actual-use conditions and included cold vacuum pressure ranging from high vacuum to no vacuum and compression loads from 0 to 20 psi. While microspheres have been recognized as a legitimate insulation material for decades, actual implementation has not been pursued. Innovative microsphere insulation system configurations and applications are evaluated.

  12. Advanced secondary power system for transport aircraft

    NASA Technical Reports Server (NTRS)

    Hoffman, A. C.; Hansen, I. G.; Beach, R. F.; Plencner, R. M.; Dengler, R. P.; Jefferies, K. S.; Frye, R. J.

    1985-01-01

    A concept for an advanced aircraft power system was identified that uses 20-kHz, 440-V, sin-wave power distribution. This system was integrated with an electrically powered flight control system and with other aircraft systems requiring secondary power. The resulting all-electric secondary power configuration reduced the empty weight of a modern 200-passenger, twin-engine transport by 10 percent and the mission fuel by 9 percent.

  13. The Advanced Technology Operations System: ATOS

    NASA Technical Reports Server (NTRS)

    Kaufeler, J.-F.; Laue, H. A.; Poulter, K.; Smith, H.

    1993-01-01

    Mission control systems supporting new space missions face ever-increasing requirements in terms of functionality, performance, reliability and efficiency. Modern data processing technology is providing the means to meet these requirements in new systems under development. During the past few years the European Space Operations Centre (ESOC) of the European Space Agency (ESA) has carried out a number of projects to demonstrate the feasibility of using advanced software technology, in particular, knowledge based systems, to support mission operations. A number of advances must be achieved before these techniques can be moved towards operational use in future missions, namely, integration of the applications into a single system framework and generalization of the applications so that they are mission independent. In order to achieve this goal, ESA initiated the Advanced Technology Operations System (ATOS) program, which will develop the infrastructure to support advanced software technology in mission operations, and provide applications modules to initially support: Mission Preparation, Mission Planning, Computer Assisted Operations, and Advanced Training. The first phase of the ATOS program is tasked with the goal of designing and prototyping the necessary system infrastructure to support the rest of the program. The major components of the ATOS architecture is presented. This architecture relies on the concept of a Mission Information Base (MIB) as the repository for all information and knowledge which will be used by the advanced application modules in future mission control systems. The MIB is being designed to exploit the latest in database and knowledge representation technology in an open and distributed system. In conclusion the technological and implementation challenges expected to be encountered, as well as the future plans and time scale of the project, are presented.

  14. Development of advanced gas turbine systems

    SciTech Connect

    Bannister, R.L.; Little, D.A.; Wiant, B.C.

    1993-11-01

    The objective of the Advanced Turbine Systems study is to investigate innovative natural gas fired cycle developments to determine the feasibility of achieving 60% efficiency within a 8-year time frame. The potential system was to be environmentally superior, cost competitive and adaptable to coal-derived fuels. Progress is described.

  15. Fiber laser cleaning of metal mirror surfaces for optical diagnostic systems of the ITER

    SciTech Connect

    Kuznetsov, A. P. Alexandrova, A. S.; Buzhinsky, O. I.; Gubskiy, K. L.; Kazieva, T. V.; Savchenkov, A. V.; Tugarinov, S. N.

    2015-12-15

    The results of experimental studies into efficiency of removal of films with a complex composition from metal mirrors by pulsed fiber laser irradiation are presented. It is shown that the initial reflectivity of optical elements can be restored by the selection of modes of irradiation impacting the surface with the sputtered film. Effective cleaning is performed by radiation with a power density lower than 10{sup 7} W/cm{sup 2}. The removal of contaminations at such a relatively low power density occurs in a solid phase, owing to which the thermal effect on the mirror is insignificant.

  16. Fiber laser cleaning of metal mirror surfaces for optical diagnostic systems of the ITER

    NASA Astrophysics Data System (ADS)

    Kuznetsov, A. P.; Alexandrova, A. S.; Buzhinsky, O. I.; Gubskiy, K. L.; Kazieva, T. V.; Savchenkov, A. V.; Tugarinov, S. N.

    2015-12-01

    The results of experimental studies into efficiency of removal of films with a complex composition from metal mirrors by pulsed fiber laser irradiation are presented. It is shown that the initial reflectivity of optical elements can be restored by the selection of modes of irradiation impacting the surface with the sputtered film. Effective cleaning is performed by radiation with a power density lower than 107 W/cm2. The removal of contaminations at such a relatively low power density occurs in a solid phase, owing to which the thermal effect on the mirror is insignificant.

  17. Advanced Energy Efficient Roof System

    SciTech Connect

    Jane Davidson

    2008-09-30

    Energy consumption in buildings represents 40 percent of primary U.S. energy consumption, split almost equally between residential (22%) and commercial (18%) buildings.1 Space heating (31%) and cooling (12%) account for approximately 9 quadrillion Btu. Improvements in the building envelope can have a significant impact on reducing energy consumption. Thermal losses (or gains) from the roof make up 14 percent of the building component energy load. Infiltration through the building envelope, including the roof, accounts for an additional 28 percent of the heating loads and 16 percent of the cooling loads. These figures provide a strong incentive to develop and implement more energy efficient roof systems. The roof is perhaps the most challenging component of the building envelope to change for many reasons. The engineered roof truss, which has been around since 1956, is relatively low cost and is the industry standard. The roof has multiple functions. A typical wood frame home lasts a long time. Building codes vary across the country. Customer and trade acceptance of new building products and materials may impede market penetration. The energy savings of a new roof system must be balanced with other requirements such as first and life-cycle costs, durability, appearance, and ease of construction. Conventional residential roof construction utilizes closely spaced roof trusses supporting a layer of sheathing and roofing materials. Gypsum board is typically attached to the lower chord of the trusses forming the finished ceiling for the occupied space. Often in warmer climates, the HVAC system and ducts are placed in the unconditioned and otherwise unusable attic. High temperature differentials and leaky ducts result in thermal losses. Penetrations through the ceilings are notoriously difficult to seal and lead to moisture and air infiltration. These issues all contribute to greater energy use and have led builders to consider construction of a conditioned attic. The

  18. Nanolaminate Mirrors With "Piston" Figure-Control Actuators

    NASA Technical Reports Server (NTRS)

    Lowman, Andrew; Redding, David; Hickey, Gregory; Knight, Jennifer; Moynihan, Philip; Lih, Shyh0Shiuh; Barbee, Troy

    2003-01-01

    Efforts are under way to develop a special class of thin-shell curved mirrors for high-resolution imaging in visible and infrared light in a variety of terrestrial or extraterrestrial applications. These mirrors can have diameters of the order of a meter and include metallic film reflectors on nanolaminate substrates supported by multiple distributed piezoceramic gpiston h-type actuators for micron-level figure control. Whereas conventional glass mirrors of equivalent size and precision have areal mass densities between 50 and 150 kg/sq m, the nanolaminate mirrors, including not only the reflector/ shell portions but also the actuators and the backing structures needed to react the actuation forces, would have areal mass densities that may approach .5 kg/m2. Moreover, whereas fabrication of a conventional glass mirror of equivalent precision takes several years, the reflector/shell portion of a nanolaminate mirror can be fabricated in less than a week, and its actuation system can be fabricated in 1 to 2 months. The engineering of these mirrors involves a fusion of the technological heritage of multisegmented adaptive optics and deformable mirrors with more recent advances in metallic nanolaminates and in mathematical modeling of the deflections of thin, curved shells in response to displacements by multiple, distributed actuators. Because a nanolaminate shell is of the order of 10 times as strong as an otherwise identical shell made of a single, high-strength, non-nanolaminate metal suitable for mirror use, a nanolaminate mirror can be made very thin (typically between 100 and 150 m from the back of the nanolaminate substrate to the front reflecting surface). The thinness and strength of the nanolaminate are what make it possible to use distributed gpiston h-type actuators for surface figure control with minimal local concentrated distortion (called print-through in the art) at the actuation points.

  19. Fokker-Planck equation in mirror research

    SciTech Connect

    Post, R.F.

    1983-08-11

    Open confinement systems based on the magnetic mirror principle depend on the maintenance of particle distributions that may deviate substantially from Maxwellian distributions. Mirror research has therefore from the beginning relied on theoretical predictions of non-equilibrium rate processes obtained from solutions to the Fokker-Planck equation. The F-P equation plays three roles: Design of experiments, creation of classical standards against which to compare experiment, and predictions concerning mirror based fusion power systems. Analytical and computational approaches to solving the F-P equation for mirror systems will be reviewed, together with results and examples that apply to specific mirror systems, such as the tandem mirror.

  20. Novel high-bandwidth bimorph deformable mirrors

    NASA Astrophysics Data System (ADS)

    Griffith, Michael S.; Laycock, Leslie C.; Archer, Nick J.

    2004-12-01

    Adaptive Optics (AO) is a critical underpinning technology for future laser delivery (including free-space optical communications), target illumination and imaging systems. It measures and compensates for optical distortion caused by transmission through the atmosphere, resulting in the ability to deploy smaller lasers and identify targets at greater ranges. One of the key components in an AO system is the wavefront modifier, which acts on the incoming or outgoing beam to counter the effects of the atmosphere. BAE SYSTEMS Advanced Technology Centre is developing multi-element bimorph deformable mirrors for such an applications. Our initial designs were based on a standard construction and exhibited a resonant frequency of 1kHz with a maximum stroke of +/-20μm for an active aperture of 50mm. These devices were limited by the necessity to have a 'dead space' between the inner active area and the mirror boundary; this ensured that both the requirements for the stroke and the fixed boundary conditions could be met simultaneously. However, there was a significant penalty to pay in terms of bandwidth, which is inversely proportional to the square of the full mirror diameter. In a series of iteration steps, we have created novel mounting arrangements that reduce dead space and thus provide the optimum trade-off between bandwidth and stroke. These schemes include supporting the mirror from underneath, rather than at its edge. As a result, models of 60mm active diameter mirrors predict a resonance in excess of 5kHz, combined with a maximum stroke greater than +/-40μm. This paper will discuss a number of different mirror designs and present experimental results for recently assembled devices.