Science.gov

Sample records for high-precision general-purpose detector

  1. High precision thermal neutron detectors

    SciTech Connect

    Radeka, V.; Schaknowski, N.A.; Smith, G.C.; Yu, B.

    1994-12-31

    Two-dimensional position sensitive detectors are indispensable in neutron diffraction experiments for determination of molecular and crystal structures in biology, solid-state physics and polymer chemistry. Some performance characteristics of these detectors are elementary and obvious, such as the position resolution, number of resolution elements, neutron detection efficiency, counting rate and sensitivity to gamma-ray background. High performance detectors are distinguished by more subtle characteristics such as the stability of the response (efficiency) versus position, stability of the recorded neutron positions, dynamic range, blooming or halo effects. While relatively few of them are needed around the world, these high performance devices are sophisticated and fairly complex, their development requires very specialized efforts. In this context, we describe here a program of detector development, based on {sup 3}He filled proportional chambers, which has been underway for some years at the Brookhaven National Laboratory. Fundamental approaches and practical considerations are outlined that have resulted in a series of high performance detectors with the best known position resolution, position stability, uniformity of response and reliability over time, for devices of this type.

  2. High precision detector robot arm system

    DOEpatents

    Shu, Deming; Chu, Yong

    2017-01-31

    A method and high precision robot arm system are provided, for example, for X-ray nanodiffraction with an X-ray nanoprobe. The robot arm system includes duo-vertical-stages and a kinematic linkage system. A two-dimensional (2D) vertical plane ultra-precision robot arm supporting an X-ray detector provides positioning and manipulating of the X-ray detector. A vertical support for the 2D vertical plane robot arm includes spaced apart rails respectively engaging a first bearing structure and a second bearing structure carried by the 2D vertical plane robot arm.

  3. Fast, High-Precision Readout Circuit for Detector Arrays

    NASA Technical Reports Server (NTRS)

    Rider, David M.; Hancock, Bruce R.; Key, Richard W.; Cunningham, Thomas J.; Wrigley, Chris J.; Seshadri, Suresh; Sander, Stanley P.; Blavier, Jean-Francois L.

    2013-01-01

    The GEO-CAPE mission described in NASA's Earth Science and Applications Decadal Survey requires high spatial, temporal, and spectral resolution measurements to monitor and characterize the rapidly changing chemistry of the troposphere over North and South Americas. High-frame-rate focal plane arrays (FPAs) with many pixels are needed to enable such measurements. A high-throughput digital detector readout integrated circuit (ROIC) that meets the GEO-CAPE FPA needs has been developed, fabricated, and tested. The ROIC is based on an innovative charge integrating, fast, high-precision analog-to-digital circuit that is built into each pixel. The 128×128-pixel ROIC digitizes all 16,384 pixels simultaneously at frame rates up to 16 kHz to provide a completely digital output on a single integrated circuit at an unprecedented rate of 262 million pixels per second. The approach eliminates the need for off focal plane electronics, greatly reducing volume, mass, and power compared to conventional FPA implementations. A focal plane based on this ROIC will require less than 2 W of power on a 1×1-cm integrated circuit. The ROIC is fabricated of silicon using CMOS technology. It is designed to be indium bump bonded to a variety of detector materials including silicon PIN diodes, indium antimonide (InSb), indium gallium arsenide (In- GaAs), and mercury cadmium telluride (HgCdTe) detector arrays to provide coverage over a broad spectral range in the infrared, visible, and ultraviolet spectral ranges.

  4. A detector interferometric calibration experiment for high precision astrometry

    NASA Astrophysics Data System (ADS)

    Crouzier, A.; Malbet, F.; Henault, F.; Léger, A.; Cara, C.; LeDuigou, J. M.; Preis, O.; Kern, P.; Delboulbe, A.; Martin, G.; Feautrier, P.; Stadler, E.; Lafrasse, S.; Rochat, S.; Ketchazo, C.; Donati, M.; Doumayrou, E.; Lagage, P. O.; Shao, M.; Goullioud, R.; Nemati, B.; Zhai, C.; Behar, E.; Potin, S.; Saint-Pe, M.; Dupont, J.

    2016-11-01

    Context. Exoplanet science has made staggering progress in the last two decades, due to the relentless exploration of new detection methods and refinement of existing ones. Yet astrometry offers a unique and untapped potential of discovery of habitable-zone low-mass planets around all the solar-like stars of the solar neighborhood. To fulfill this goal, astrometry must be paired with high precision calibration of the detector. Aims: We present a way to calibrate a detector for high accuracy astrometry. An experimental testbed combining an astrometric simulator and an interferometric calibration system is used to validate both the hardware needed for the calibration and the signal processing methods. The objective is an accuracy of 5 × 10-6 pixel on the location of a Nyquist sampled polychromatic point spread function. Methods: The interferometric calibration system produced modulated Young fringes on the detector. The Young fringes were parametrized as products of time and space dependent functions, based on various pixel parameters. The minimization of function parameters was done iteratively, until convergence was obtained, revealing the pixel information needed for the calibration of astrometric measurements. Results: The calibration system yielded the pixel positions to an accuracy estimated at 4 × 10-4 pixel. After including the pixel position information, an astrometric accuracy of 6 × 10-5 pixel was obtained, for a PSF motion over more than five pixels. In the static mode (small jitter motion of less than 1 × 10-3 pixel), a photon noise limited precision of 3 × 10-5 pixel was reached.

  5. High Precision Thermal, Structural and Optical Analysis of an External Occulter Using a Common Model and the General Purpose Multi-Physics Analysis Tool Cielo

    NASA Technical Reports Server (NTRS)

    Hoff, Claus; Cady, Eric; Chainyk, Mike; Kissil, Andrew; Levine, Marie; Moore, Greg

    2011-01-01

    The efficient simulation of multidisciplinary thermo-opto-mechanical effects in precision deployable systems has for years been limited by numerical toolsets that do not necessarily share the same finite element basis, level of mesh discretization, data formats, or compute platforms. Cielo, a general purpose integrated modeling tool funded by the Jet Propulsion Laboratory and the Exoplanet Exploration Program, addresses shortcomings in the current state of the art via features that enable the use of a single, common model for thermal, structural and optical aberration analysis, producing results of greater accuracy, without the need for results interpolation or mapping. This paper will highlight some of these advances, and will demonstrate them within the context of detailed external occulter analyses, focusing on in-plane deformations of the petal edges for both steady-state and transient conditions, with subsequent optical performance metrics including intensity distributions at the pupil and image plane.

  6. High Precision Thermal, Structural and Optical Analysis of an External Occulter Using a Common Model and the General Purpose Multi-Physics Analysis Tool Cielo

    NASA Technical Reports Server (NTRS)

    Hoff, Claus; Cady, Eric; Chainyk, Mike; Kissil, Andrew; Levine, Marie; Moore, Greg

    2011-01-01

    The efficient simulation of multidisciplinary thermo-opto-mechanical effects in precision deployable systems has for years been limited by numerical toolsets that do not necessarily share the same finite element basis, level of mesh discretization, data formats, or compute platforms. Cielo, a general purpose integrated modeling tool funded by the Jet Propulsion Laboratory and the Exoplanet Exploration Program, addresses shortcomings in the current state of the art via features that enable the use of a single, common model for thermal, structural and optical aberration analysis, producing results of greater accuracy, without the need for results interpolation or mapping. This paper will highlight some of these advances, and will demonstrate them within the context of detailed external occulter analyses, focusing on in-plane deformations of the petal edges for both steady-state and transient conditions, with subsequent optical performance metrics including intensity distributions at the pupil and image plane.

  7. High-precision efficiency calibration of a high-purity co-axial germanium detector

    NASA Astrophysics Data System (ADS)

    Blank, B.; Souin, J.; Ascher, P.; Audirac, L.; Canchel, G.; Gerbaux, M.; Grévy, S.; Giovinazzo, J.; Guérin, H.; Nieto, T. Kurtukian; Matea, I.; Bouzomita, H.; Delahaye, P.; Grinyer, G. F.; Thomas, J. C.

    2015-03-01

    A high-purity co-axial germanium detector has been calibrated in efficiency to a precision of about 0.15% over a wide energy range. High-precision scans of the detector crystal and γ-ray source measurements have been compared to Monte-Carlo simulations to adjust the dimensions of a detector model. For this purpose, standard calibration sources and short-lived online sources have been used. The resulting efficiency calibration reaches the precision needed e.g. for branching ratio measurements of super-allowed β decays for tests of the weak-interaction standard model.

  8. Magnetic Microcalorimeter Gamma Detectors for High-Precision Non-Destructive Analysis

    SciTech Connect

    Friedrich, Stephan; Bates, Cameron; Pereverzev, Sergey

    2014-10-03

    Cryogenic gamma (γ) detectors with operating temperatures of ~0.1 K offer 10× better energy resolution than conventional high-purity germanium detectors that are currently used for non-destructive analysis (NDA) of nuclear materials. This can greatly increase the accuracy of NDA, especially at low-energies where gamma rays often have similar energies and cannot be resolved by Ge detectors. Among the different cryogenic detector types, Magnetic Micro-Calorimeters (MMCs) have the potential of faster count rates and better linearity. High linearity is essential to add spectra from different pixels in detector arrays that are needed for high sensitivity. MMC gamma detectors measure the energy of absorbed gamma rays form the resulting change in magnetization of an erbium-doped gold (Au:Er) sensor. The signal is read out with a SQUID preamplifier and processed digitally with room temperature electronics (see inset figure 2). The objective of this project is to develop ultra-high energy resolution γ-detectors based on magnetic micro-calorimeters (MMCs) for accurate non-destructive isotope analysis (NDA). Since MMCs, like other cryogenic γ-detector technologies with operating temperatures <0.1 K, are intrinsically slow and have to be small for high resolution, special emphasis will be placed on questions that determine sensitivity and the potential for scaling to arrays. Objectives for FY14 were therefore to fabricate an improved version of MMC γ-detectors and test their energy resolution, maximum count rate, readout noise, crosstalk between pixels and linearity.

  9. The EMIR detector translation unit: a cryogenic high-precision 3-DoF parallel mechanism

    NASA Astrophysics Data System (ADS)

    Zago, Lorenzo; Droz, Serge; Racz, Livia; Molins, Albert

    2006-06-01

    The paper describes a 3-DoF translational (XYZ) mechanism for the main detector of the EMIR multi-object spectrograph, developed for the GTC telescope. This mechanism is designed for the cryogenic environment (77 K) and consists of a parallel manipulator with flexure joints, actuated by three identical and symmetrically located linear actuators.

  10. Exploratory study of a novel low occupancy vertex detector architecture based on high precision timing for high luminosity particle colliders

    NASA Astrophysics Data System (ADS)

    Orel, Peter; Varner, Gary S.; Niknejadi, Pardis

    2017-06-01

    Vertex detectors provide space-time coordinates for the traversing charged particle decay products closest to the interaction point. Resolving these increasingly intense particle fluences at high luminosity particle colliders, such as SuperKEKB, is an ever growing challenge. This results in a non-negligible occupancy of the vertex detector using existing low material budget techniques. Consequently, new approaches are being studied that meet the vertexing requirements while lowering the occupancy. In this paper, we introduce a novel vertex detector architecture. Its design relies on an asynchronous digital pixel matrix in combination with a readout based on high precision time-of-flight measurement. Denoted the Timing Vertex Detector (TVD), it consists of a binary pixel array, a transmission line for signal collection, and a readout ASIC. The TVD aims to have a spatial resolution comparable to the existing Belle2 vertex detector. At the same time it offers a reduced occupancy by a factor of ten while decreasing the channel count by almost three orders of magnitude. Consequently, reducing the event size from about 1 MB/event to about 5.9 kB/event.

  11. New high-precision drift-tube detectors for the ATLAS muon spectrometer

    NASA Astrophysics Data System (ADS)

    Kroha, H.; Fakhrutdinov, R.; Kozhin, A.

    2017-06-01

    Small-diameter muon drift tube (sMDT) detectors have been developed for upgrades of the ATLAS muon spectrometer. With a tube diameter of 15 mm, they provide an about an order of magnitude higher rate capability than the present ATLAS muon tracking detectors, the MDT chambers with 30 mm tube diameter. The drift-tube design and the construction methods have been optimised for mass production and allow for complex shapes required for maximising the acceptance. A record sense wire positioning accuracy of 5 μm has been achieved with the new design. In the serial production, the wire positioning accuracy is routinely better than 10 μm. 14 new sMDT chambers are already operational in ATLAS, further 16 are under construction for installation in the 2019-2020 LHC shutdown. For the upgrade of the barrel muon spectrometer for High-Luminosity LHC, 96 sMDT chambers will be contructed between 2020 and 2024.

  12. Modeling of high-precision wavefront sensing with new generation of CMT avalanche photodiode infrared detectors.

    PubMed

    Gousset, Silvère; Petit, Cyril; Michau, Vincent; Fusco, Thierry; Robert, Clelia

    2015-12-01

    Near-infrared wavefront sensing allows for the enhancement of sky coverage with adaptive optics. The recently developed HgCdTe avalanche photodiode arrays are promising due to their very low detector noise, but still present an imperfect cosmetic that may directly impact real-time wavefront measurements for adaptive optics and thus degrade performance in astronomical applications. We propose here a model of a Shack-Hartmann wavefront measurement in the presence of residual fixed pattern noise and defective pixels. To adjust our models, a fine characterization of such an HgCdTe array, the RAPID sensor, is proposed. The impact of the cosmetic defects on the Shack-Hartmann measurement is assessed through numerical simulations. This study provides both a new insight on the applicability of cadmium mercury telluride (CMT) avalanche photodiodes detectors for astronomical applications and criteria to specify the cosmetic qualities of future arrays.

  13. SALT, a dedicated readout chip for high precision tracking silicon strip detectors at the LHCb Upgrade

    NASA Astrophysics Data System (ADS)

    Bugiel, Sz.; Dasgupta, R.; Firlej, M.; Fiutowski, T.; Idzik, M.; Kuczynska, M.; Moron, J.; Swientek, K.; Szumlak, T.

    2016-02-01

    The Upstream Tracker (UT) silicon strip detector, one of the central parts of the tracker system of the modernised LHCb experiment, will use a new 128-channel readout ASIC called SALT. It will extract and digitise analogue signals from the UT sensors, perform digital signal processing and transmit a serial output data. The SALT is being designed in CMOS 130 nm process and uses a novel architecture comprising of analog front-end and fast (40 MSps) ultra-low power (<0.5 mW) 6-bit ADC in each channel. The prototype ASICs of important functional blocks, like analogue front-end, 6-bit SAR ADC, PLL, and DLL, were designed, fabricated and tested. A prototype of an 8-channel version of the SALT chip, comprising all important functionalities was also designed and fabricated. The architecture and design of the SALT, together with the selected preliminary tests results, are presented.

  14. General purpose bioamplifier study

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Based on known inputs and outputs, a set of specifications were developed for the major characteristics of a general purpose amplifier for use in the Integrated Medical, Behaviorial, and Laboratory Measurement System.

  15. Recent progress of MPPC-based scintillation detectors in high precision X-ray and gamma-ray imaging

    NASA Astrophysics Data System (ADS)

    Kataoka, J.; Kishimoto, A.; Fujita, T.; Nishiyama, T.; Kurei, Y.; Tsujikawa, T.; Oshima, T.; Taya, T.; Iwamoto, Y.; Ogata, H.; Okochi, H.; Ohsuka, S.; Ikeda, H.; Yamamoto, S.

    2015-06-01

    The multi-pixel photon counter (MPPC) is a promising light sensor for various applications, not only in physics experiments but also in nuclear medicine, industry, and even high-energy astrophysics. In this paper, we present the current status and most recent progress of the MPPC-based scintillation detectors, such as (1) a high-precision X-ray and gamma-ray spectral image sensor, (2) next-generation PET detectors with MRI, TOF, and DOI measurement capabilities, and (3) a compact gamma camera for environmental radiation surveys. We first present a new method of fabricating a Ce:GAGG scintillator plate (1 or 2 mm thick) with ultra-fine resolution (0.2 mm/pixel), cut using a dicing saw to create 50 μm wide micro-grooves. When the plate is optically coupled with a large-area MPPC array, excellent spatial resolution of 0.48 mm (FWHM) and energy resolution of 14% (FWHM) are obtained for 122 keV gamma rays. Hence, the detector can act as a convenient "multi-color" imaging device that can potentially be used for future SPECT and photon-counting CT. We then show a prototype system for a high-resolution MPPC-based PET scanner that can realize ≃1 mm (FWHM) spatial resolution, even under a strong magnetic field of 4.7 T. We develop a front-end ASIC intended for future TOF-PET scanner with a 16-channel readout that achieves a coincidence time resolution of 489 ps (FWHM). A novel design for a module with DOI-measurement capability for gamma rays is also presented by measuring the pulse height ratio of double-sided MPPCs coupled at both ends of scintillation crystal block. Finally, we present the concept of a two-plane Compton camera consisting of Ce:GAGG scintillator arrays coupled with thin MPPC arrays. As a result of the thin and compact features of the MPPC device, the camera not only achieves a small size (14×14×15 cm3) and light weight (1.9 kg) but also excellent sensitivity, compared to the conventional PMT-based pinhole camera used in Fukushima. Finally, we briefly

  16. Optomechanical design of a high-precision detector robot arm system for x-ray nano-diffraction with x-ray nanoprobe

    NASA Astrophysics Data System (ADS)

    Shu, D.; Kalbfleisch, S.; Kearney, S.; Anton, J.; Chu, Y. S.

    2014-03-01

    Collaboration between Argonne National Laboratory and Brookhaven National Laboratory has created a design for the high-precision detector robot arm system that will be used in the x-ray nano-diffraction experimental station at the Hard X-ray Nanoprobe (HXN) beamline for the NSLS-II project. The robot arm system is designed for positioning and manipulating an x-ray detector in three-dimensional space for nano-diffraction data acquisition with the HXN x-ray microscope. It consists of the following major component groups: a granite base with air-bearing support, a 2-D horizontal base stage, a vertical axis goniometer, a 2-D vertical plane robot arm, a 3-D fast scanning stages group, and a 2-D x-ray pixel detector. The design specifications and unique optomechanical structure of this novel high-precision detector robot arm system will be presented in this paper.

  17. GENERAL PURPOSE ADA PACKAGES

    NASA Technical Reports Server (NTRS)

    Klumpp, A. R.

    1994-01-01

    Ten families of subprograms are bundled together for the General-Purpose Ada Packages. The families bring to Ada many features from HAL/S, PL/I, FORTRAN, and other languages. These families are: string subprograms (INDEX, TRIM, LOAD, etc.); scalar subprograms (MAX, MIN, REM, etc.); array subprograms (MAX, MIN, PROD, SUM, GET, and PUT); numerical subprograms (EXP, CUBIC, etc.); service subprograms (DATE_TIME function, etc.); Linear Algebra II; Runge-Kutta integrators; and three text I/O families of packages. In two cases, a family consists of a single non-generic package. In all other cases, a family comprises a generic package and its instances for a selected group of scalar types. All generic packages are designed to be easily instantiated for the types declared in the user facility. The linear algebra package is LINRAG2. This package includes subprograms supplementing those in NPO-17985, An Ada Linear Algebra Package Modeled After HAL/S (LINRAG). Please note that LINRAG2 cannot be compiled without LINRAG. Most packages have widespread applicability, although some are oriented for avionics applications. All are designed to facilitate writing new software in Ada. Several of the packages use conventions introduced by other programming languages. A package of string subprograms is based on HAL/S (a language designed for the avionics software in the Space Shuttle) and PL/I. Packages of scalar and array subprograms are taken from HAL/S or generalized current Ada subprograms. A package of Runge-Kutta integrators is patterned after a built-in MAC (MIT Algebraic Compiler) integrator. Those packages modeled after HAL/S make it easy to translate existing HAL/S software to Ada. The General-Purpose Ada Packages program source code is available on two 360K 5.25" MS-DOS format diskettes. The software was developed using VAX Ada v1.5 under DEC VMS v4.5. It should be portable to any validated Ada compiler and it should execute either interactively or in batch. The largest package

  18. GENERAL PURPOSE ADA PACKAGES

    NASA Technical Reports Server (NTRS)

    Klumpp, A. R.

    1994-01-01

    Ten families of subprograms are bundled together for the General-Purpose Ada Packages. The families bring to Ada many features from HAL/S, PL/I, FORTRAN, and other languages. These families are: string subprograms (INDEX, TRIM, LOAD, etc.); scalar subprograms (MAX, MIN, REM, etc.); array subprograms (MAX, MIN, PROD, SUM, GET, and PUT); numerical subprograms (EXP, CUBIC, etc.); service subprograms (DATE_TIME function, etc.); Linear Algebra II; Runge-Kutta integrators; and three text I/O families of packages. In two cases, a family consists of a single non-generic package. In all other cases, a family comprises a generic package and its instances for a selected group of scalar types. All generic packages are designed to be easily instantiated for the types declared in the user facility. The linear algebra package is LINRAG2. This package includes subprograms supplementing those in NPO-17985, An Ada Linear Algebra Package Modeled After HAL/S (LINRAG). Please note that LINRAG2 cannot be compiled without LINRAG. Most packages have widespread applicability, although some are oriented for avionics applications. All are designed to facilitate writing new software in Ada. Several of the packages use conventions introduced by other programming languages. A package of string subprograms is based on HAL/S (a language designed for the avionics software in the Space Shuttle) and PL/I. Packages of scalar and array subprograms are taken from HAL/S or generalized current Ada subprograms. A package of Runge-Kutta integrators is patterned after a built-in MAC (MIT Algebraic Compiler) integrator. Those packages modeled after HAL/S make it easy to translate existing HAL/S software to Ada. The General-Purpose Ada Packages program source code is available on two 360K 5.25" MS-DOS format diskettes. The software was developed using VAX Ada v1.5 under DEC VMS v4.5. It should be portable to any validated Ada compiler and it should execute either interactively or in batch. The largest package

  19. Magnetic Microcalorimeter Gamma Detectors for High-Precision Non-Destructive Analysis, FY14 Extended Annual Report

    SciTech Connect

    Friedrich, S.

    2015-02-06

    Cryogenic gamma (γ) detectors with operating temperatures of ~0.1 K or below offer 10× better energy resolution than conventional high-purity germanium detectors that are currently used for non-destructive analysis (NDA) of nuclear materials. This can greatly increase the accuracy of NDA, especially at low-energies where gamma rays often have similar energies and cannot be resolved by Ge detectors. We are developing cryogenic γ–detectors based on metallic magnetic calorimeters (MMCs), which have the potential of higher resolution, faster count rates and better linearity than other cryogenic detector technologies. High linearity is essential to add spectra from different pixels in detector arrays that are needed for high sensitivity. Here we discuss the fabrication of a new generation of MMC γ–detectors in FY2014, and the resulting improvements in energy resolution and linearity of the new design. As an example of the type of NDA that cryogenic detectors enable, we demonstrate the direct detection of Pu-242 emissions with our MMC γ–detectors in the presence of Pu-240, and show that a quantitative NDA analysis agrees with the mass spectrometry

  20. Reduction of a grid moire pattern by integrating a carbon-interspaced high precision x-ray grid with a digital radiographic detector

    SciTech Connect

    Yoon, Jai-Woong; Park, Young-Guk; Park, Chun-Joo; Kim, Do-Il; Lee, Jin-Ho; Chung, Nag-Kun; Choe, Bo-Young; Suh, Tae-Suk; Lee, Hyoung-Koo

    2007-11-15

    The stationary grid commonly used with a digital x-ray detector causes a moire interference pattern due to the inadequate sampling of the grid shadows by the detector pixels. There are limitations with the previous methods used to remove the moire such as imperfect electromagnetic interference shielding and the loss of image information. A new method is proposed for removing the moire pattern by integrating a carbon-interspaced high precision x-ray grid with high grid line uniformity with the detector for frequency matching. The grid was aligned to the detector by translating and rotating the x-ray grid with respect to the detector using microcontrolled alignment mechanism. The gap between the grid and the detector surface was adjusted with micrometer precision to precisely match the projected grid line pitch to the detector pixel pitch. Considering the magnification of the grid shadows on the detector plane, the grids were manufactured such that the grid line frequency was slightly higher than the detector sampling frequency. This study examined the factors that affect the moire pattern, particularly the line frequency and displacement. The frequency of the moire pattern was found to be sensitive to the angular displacement of the grid with respect to the detector while the horizontal translation alters the phase but not the moire frequency. The frequency of the moire pattern also decreased with decreasing difference in frequency between the grid and the detector, and a moire-free image was produced after complete matching for a given source to detector distance. The image quality factors including the contrast, signal-to-noise ratio and uniformity in the images with and without the moire pattern were investigated.

  1. Reduction of a grid moiré pattern by integrating a carbon-interspaced high precision x-ray grid with a digital radiographic detector.

    PubMed

    Yoon, Jai-Woong; Park, Young-Guk; Park, Chun-Joo; Kim, Do-Il; Lee, Jin-Ho; Chung, Nag-Kun; Choe, Bo-Young; Suh, Tae-Suk; Lee, Hyoung-Koo

    2007-11-01

    The stationary grid commonly used with a digital x-ray detector causes a moiré interference pattern due to the inadequate sampling of the grid shadows by the detector pixels. There are limitations with the previous methods used to remove the moiré such as imperfect electromagnetic interference shielding and the loss of image information. A new method is proposed for removing the moiré pattern by integrating a carbon-interspaced high precision x-ray grid with high grid line uniformity with the detector for frequency matching. The grid was aligned to the detector by translating and rotating the x-ray grid with respect to the detector using microcontrolled alignment mechanism. The gap between the grid and the detector surface was adjusted with micrometer precision to precisely match the projected grid line pitch to the detector pixel pitch. Considering the magnification of the grid shadows on the detector plane, the grids were manufactured such that the grid line frequency was slightly higher than the detector sampling frequency. This study examined the factors that affect the moiré pattern, particularly the line frequency and displacement. The frequency of the moiré pattern was found to be sensitive to the angular displacement of the grid with respect to the detector while the horizontal translation alters the phase but not the moiré frequency. The frequency of the moiré pattern also decreased with decreasing difference in frequency between the grid and the detector, and a moiré-free image was produced after complete matching for a given source to detector distance. The image quality factors including the contrast, signal-to-noise ratio and uniformity in the images with and without the moiré pattern were investigated.

  2. High-precision excited state lifetime measurements in rare earth nuclei using LaBr3(Ce) detectors

    NASA Astrophysics Data System (ADS)

    Williams, E.; Cooper, N.; Bonett-Matiz, M.; Werner, V.; Régis, J.-M.; Rudigier, M.; Ahn, T.; Anagnostatou, V.; Berant, Z.; Bunce, M.; Elvers, M.; Heinz, A.; Ilie, G.; Jolie, J.; Radeck, D.; Savran, D.; Smith, M.

    2012-10-01

    To study how collective nuclear structure evolves towards mid-shell and test next-generation LaBr3(Ce) scintillation detectors, measurements of the lifetimes of 21+ states in 168Hf and 174W were conducted at the Wright Nuclear Structure Laboratory. Preliminary results indicate that the excellent time and energy resolution of LaBr3 detectors make them well suited to fast timing measurements, allowing for improved background subtraction and peak resolution in comparison to BaF2 detectors. Preliminary analysis shows an order of magnitude reduction in the statistical error of the 2+ lifetimes in comparison to literature values for both nuclei. In the case of 174W, a substantial reduction of the observed lifetime hints at the possibility of new physics in the region.

  3. Initial performance studies of a general-purpose detector for multi-TeV physics at a 100 TeV pp collider

    DOE PAGES

    Chekanov, S. V.; Beydler, M.; Kotwal, A. V.; ...

    2017-06-13

    This paper describes simulations of detector response to multi-TeV physics at the Future Circular Collider (FCC-hh) or Super proton-proton Collider (SppC) which aim to collide proton beams with a centre-of-mass energy of 100 TeV. The unprecedented energy regime of these future experiments imposes new requirements on detector technologies which can be studied using the detailed geant4 simulations presented in this paper. The initial performance of a detector designed for physics studies at the FCC-hh or SppC experiments are described with an emphasis on measurements of single particles up to 33 TeV in transverse momentum. Furthermore, the granularity requirements for calorimetrymore » are investigated using the two-particle spatial resolution achieved for hadron showers.« less

  4. Initial Performance Studies of a General-Purpose Detector for Multi-TeV Physics at a 100 TeV pp Collider

    SciTech Connect

    Chekanov, S. V.; Beydler, M.; Kotwal, A. V.; Gray, L.; Sen, S.; Tran, N. V.; Yu, S. -S.; Zuzelski, J.

    2016-12-21

    This paper describes simulations of detector response to multi-TeV physics at the Future Circular Collider (FCC-hh) or Super proton-proton Collider (SppC) which aim to collide proton beams with a centre-of-mass energy of 100 TeV. The unprecedented energy regime of these future experiments imposes new requirements on detector technologies which can be studied using the detailed GEANT4 simulations presented in this paper. The initial performance of a detector designed for physics studies at the FCC-hh or SppC experiments is described with an emphasis on measurements of single particles up to 33 TeV in transverse momentum. The reconstruction of hadronic jets has also been studied in the transverse momentum range from 50 GeV to 26 TeV. The granularity requirements for calorimetry are investigated using the two-particle spatial resolution achieved for hadron showers.

  5. Initial performance studies of a general-purpose detector for multi-TeV physics at a 100 TeV pp collider

    NASA Astrophysics Data System (ADS)

    Chekanov, S. V.; Beydler, M.; Kotwal, A. V.; Gray, L.; Sen, S.; Tran, N. V.; Yu, S.-S.; Zuzelski, J.

    2017-06-01

    This paper describes simulations of detector response to multi-TeV particles and jets at the Future Circular Collider (FCC-hh) or Super proton-proton Collider (SppC) which aim to collide proton beams with a centre-of-mass energy of 100 TeV. The unprecedented energy regime of these future experiments imposes new requirements on detector technologies which can be studied using the detailed GEANT4 simulations presented in this paper. The initial performance of a detector designed for physics studies at the FCC-hh or SppC experiments is described with an emphasis on measurements of single particles up to 33 TeV in transverse momentum. The reconstruction of hadronic jets has also been studied in the transverse momentum range from 50 GeV to 26 TeV. The granularity requirements for calorimetry are investigated using the two-particle spatial resolution achieved for hadron showers.

  6. Investigation of CMOS pixel sensor with 0.18 μm CMOS technology for high-precision tracking detector

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Fu, M.; Zhang, Y.; Yan, W.; Wang, M.

    2017-01-01

    The Circular Electron Positron Collider (CEPC) proposed by the Chinese high energy physics community is aiming to measure Higgs particles and their interactions precisely. The tracking detector including Silicon Inner Tracker (SIT) and Forward Tracking Disks (FTD) has driven stringent requirements on sensor technologies in term of spatial resolution, power consumption and readout speed. CMOS Pixel Sensor (CPS) is a promising candidate to approach these requirements. This paper presents the preliminary studies on the sensor optimization for tracking detector to achieve high collection efficiency while keeping necessary spatial resolution. Detailed studies have been performed on the charge collection using a 0.18 μm CMOS image sensor process. This process allows high resistivity epitaxial layer, leading to a significant improvement on the charge collection and therefore improving the radiation tolerance. Together with the simulation results, the first exploratory prototype has bee designed and fabricated. The prototype includes 9 different pixel arrays, which vary in terms of pixel pitch, diode size and geometry. The total area of the prototype amounts to 2 × 7.88 mm2.

  7. General purpose programmable accelerator board

    DOEpatents

    Robertson, Perry J.; Witzke, Edward L.

    2001-01-01

    A general purpose accelerator board and acceleration method comprising use of: one or more programmable logic devices; a plurality of memory blocks; bus interface for communicating data between the memory blocks and devices external to the board; and dynamic programming capabilities for providing logic to the programmable logic device to be executed on data in the memory blocks.

  8. A VHSIC general purpose processor

    NASA Technical Reports Server (NTRS)

    Benz, H. F.

    1985-01-01

    The very high speed integrated circuit (VHSIC) program offers NASA and its contractors assured availability of military specification embedded computer components and integrated computer aided design/computer aided engineering and software development support that result in low system life costs for data management systems on the space station and the Earth Observatory Satellite. Viewgraphs given review progress in both the Department of Defense VHSIC program and the NASA VHSIC related insertion development of a general purpose processor are presented.

  9. General purpose steam table library :

    SciTech Connect

    Carpenter, John H.; Belcourt, Kenneth Noel; Nourgaliev, Robert

    2013-08-01

    Completion of the CASL L3 milestone THM.CFD.P7.04 provides a general purpose tabular interpolation library for material properties to support, in particular, standardized models for steam properties. The software consists of three parts, implementations of analytic steam models, a code to generate tables from those models, and an interpolation package to interface the tables to CFD codes such as Hydra-TH. Verification of the standard model is maintained through the entire train of routines. The performance of interpolation package exceeds that of freely available analytic implementation of the steam properties by over an order of magnitude.

  10. General Purpose Heat Source Simulator

    NASA Technical Reports Server (NTRS)

    Emrich, Bill

    2008-01-01

    The General Purpose Heat Source (GPHS) simulator project is designed to replicate through the use of electrical heaters, the form, fit, and function of actual GPHS modules which generate heat through the radioactive decay of Pu238. The use of electrically heated modules rather than modules containing Pu238 facilitates the testing of spacecraft subsystems and systems without sacrificing the quantity and quality of the test data gathered. Previous GPHS activities are centered around developing robust heater designs with sizes and weights that closely matched those of actual Pu238 fueled GPHS blocks. These efforts were successful, although their maximum temperature capabilities were limited to around 850 C. New designs are being pursued which also replicate the sizes and weights of actual Pu238 fueled GPHS blocks but will allow operation up to 1100 C.

  11. General Purpose Heat Source Simulator

    NASA Technical Reports Server (NTRS)

    Emrich, William J., Jr.

    2008-01-01

    The General Purpose Heat Source (GPHS) project seeks to combine the development of an electrically heated, single GPHS module simulator with the evaluation of potential nuclear surface power systems. The simulator is designed to match the form, fit, and function of actual GPHS modules which normally generate heat through the radioactive decay of Pu238. The use of electrically heated modules rather than modules containing Pu238 facilitates the testing of the subsystems and systems without sacrificing the quantity and quality of the test data gathered. Current GPHS activities are centered on developing robust heater designs with sizes and weights which closely match those of actual Pu238 fueled GPHS blocks. Designs are being pursued which will allow operation up to 1100 C.

  12. General Purpose Heat Source Simulator

    NASA Technical Reports Server (NTRS)

    Emrich, Bill

    2008-01-01

    The General Purpose Heat Source (GPHS) simulator project is designed to replicate through the use of electrical heaters, the form, fit, and function of actual GPHS modules which generate heat through the radioactive decay of Pu238. The use of electrically heated modules rather than modules containing Pu238 facilitates the testing of spacecraft subsystems and systems without sacrificing the quantity and quality of the test data gathered. Previous GPHS activities are centered around developing robust heater designs with sizes and weights that closely matched those of actual Pu238 fueled GPHS blocks. These efforts were successful, although their maximum temperature capabilities were limited to around 850 C. New designs are being pursued which also replicate the sizes and weights of actual Pu238 fueled GPHS blocks but will allow operation up to 1100 C.

  13. High Precision GPS Measurements

    DTIC Science & Technology

    2010-02-28

    GNSS Service (IGS) database, and magnetic field vectors from the International Geomagnetic Reference Field (IGRF) model [9]. These combined...Additonal correlations between the higher order range error and geomagnetic activity and seasonal variations are also obtained. Fig. 4 shows...clear correlation between the geomagnetic activity and enhanced higher order error at both sites. High Precision GPS Final Report Page 5 Fig.3

  14. General-purpose infusion pumps.

    PubMed

    1998-01-01

    General-purpose infusion pumps deliver liquid medications to patients through intravenous or epidural routes at specified flows. They are most often used in hospitals and alternative care settings (e.g., physician' offices, patients' homes) when liquid medications need to be administered with greater accuracy or at higher flows than can be provided through a manually adjusted gravity administration set. In this Update of our February 1997 Evaluation of infusion pumps (Health Devices 26[2]), we tested 3 additional pumps from 3 suppliers. We also rated and ranked them in comparison with the 16 units from the February 1997 study that are still being produced. With a few exceptions, we tested the new pumps against the same criteria and using the same test methods as those in the previous Evaluation. However, for this Update, the focus of our findings has broadened: although we continue to place strong emphasis on the pumps' protection against gravity free-flow, we also give significant weight to their overall safety, performance, and human factors design. As a result, our ratings and rankings scheme has changed, affecting the rankings of some of the previously evaluated units. Of the 19 currently available units that have been evaluated to date, we rated 13 units Acceptable, with 5 of those units ranked above the other 8. A further 5 units were rated Conditionally Acceptable; we consider them Acceptable if they are used with the available free-flow protection. And 1 unit had performance problems that caused us to rate it Unacceptable (this unit has been recalled by its supplier; see the inset on page 162). As always, we caution readers not to base selection and purchasing decisions on our conclusions alone, but on a thorough understanding of the issues behind those conclusions, which can be gained by reading this Evaluation in its entirety and carefully reviewing the February 1997 issue.

  15. Validation of an analytical method for simultaneous high-precision measurements of greenhouse gas emissions from wastewater treatment plants using a gas chromatography-barrier discharge detector system.

    PubMed

    Pascale, Raffaella; Caivano, Marianna; Buchicchio, Alessandro; Mancini, Ignazio M; Bianco, Giuliana; Caniani, Donatella

    2017-01-13

    Wastewater treatment plants (WWTPs) emit CO2 and N2O, which may lead to climate change and global warming. Over the last few years, awareness of greenhouse gas (GHG) emissions from WWTPs has increased. Moreover, the development of valid, reliable, and high-throughput analytical methods for simultaneous gas analysis is an essential requirement for environmental applications. In the present study, an analytical method based on a gas chromatograph (GC) equipped with a barrier ionization discharge (BID) detector was developed for the first time. This new method simultaneously analyses CO2 and N2O and has a precision, measured in terms of relative standard of variation RSD%, equal to or less than 6.6% and 5.1%, respectively. The method's detection limits are 5.3ppmv for CO2 and 62.0ppbv for N2O. The method's selectivity, linearity, accuracy, repeatability, intermediate precision, limit of detection and limit of quantification were good at trace concentration levels. After validation, the method was applied to a real case of N2O and CO2 emissions from a WWTP, confirming its suitability as a standard procedure for simultaneous GHG analysis in environmental samples containing CO2 levels less than 12,000mg/L.

  16. Performing elemental microanalysis with high accuracy and high precision by scanning electron microscopy/silicon drift detector energy-dispersive X-ray spectrometry (SEM/SDD-EDS).

    PubMed

    Newbury, Dale E; Ritchie, Nicholas W M

    Electron-excited X-ray microanalysis performed in the scanning electron microscope with energy-dispersive X-ray spectrometry (EDS) is a core technique for characterization of the microstructure of materials. The recent advances in EDS performance with the silicon drift detector (SDD) enable accuracy and precision equivalent to that of the high spectral resolution wavelength-dispersive spectrometer employed on the electron probe microanalyzer platform. SDD-EDS throughput, resolution, and stability provide practical operating conditions for measurement of high-count spectra that form the basis for peak fitting procedures that recover the characteristic peak intensities even for elemental combination where severe peak overlaps occur, such PbS, MoS2, BaTiO3, SrWO4, and WSi2. Accurate analyses are also demonstrated for interferences involving large concentration ratios: a major constituent on a minor constituent (Ba at 0.4299 mass fraction on Ti at 0.0180) and a major constituent on a trace constituent (Ba at 0.2194 on Ce at 0.00407; Si at 0.1145 on Ta at 0.0041). Accurate analyses of low atomic number elements, C, N, O, and F, are demonstrated. Measurement of trace constituents with limits of detection below 0.001 mass fraction (1000 ppm) is possible within a practical measurement time of 500 s.

  17. General Purpose Ground Forces: What Purpose?

    DTIC Science & Technology

    1993-04-06

    RCH~V~AL COPY NATIONAL WAR COLLEGE "GENERAL PURPOSE GROUND FORCES" WHAT PURPOSE ?" LTC DAN CHALLIS 6 APRIL 1993 N A T I O N A L...06-04-1993 to 06-04-1993 4. TITLE AND SUBTITLE General Purpose Ground Forces: What Purpose ? 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...The ~Jarm glow of a much heralded Cold War victory, plus the Gulf War t:ciumph, the growth of democracy in developing countries, and the apparent

  18. NASTRAN general purpose interface requirements document

    NASA Technical Reports Server (NTRS)

    Brown, W. K.; Douglas, F. J.; Mcdonough, J. R.; Ziobro, D. J.

    1978-01-01

    This NASTRAN (NASA STRuctural ANalysis) General Purpose Interface Requirements Document (IRD) defines standards for deliverables required of New Capability Contractors (NCCs) and relates these deliverables to the software development cycle. It also defines standards to be followed by NCCs for adding to and modifying the code in the NASTRAN software system and for adding to and modifying the four official NASTRAN manuals: The NASTRAN Theoretical Manual, the NASTRAN User's Manual, The NASTRAN Programmer's Manual, and The NASTRAN Demonstration Problem Manual. It is intended that this General Purpose IRD shall be incorporated by reference in all contracts for a new NASTRAN capability.

  19. 7 CFR 254.1 - General purpose.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE GENERAL REGULATIONS AND POLICIES-FOOD DISTRIBUTION ADMINISTRATION OF THE FOOD DISTRIBUTION PROGRAM FOR INDIAN HOUSEHOLDS IN OKLAHOMA § 254.1 General purpose. This part sets the requirement under...

  20. 7 CFR 254.1 - General purpose.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE GENERAL REGULATIONS AND POLICIES-FOOD DISTRIBUTION ADMINISTRATION OF THE FOOD DISTRIBUTION PROGRAM FOR INDIAN HOUSEHOLDS IN OKLAHOMA § 254.1 General purpose. This part sets the requirement under...

  1. 7 CFR 254.1 - General purpose.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE GENERAL REGULATIONS AND POLICIES-FOOD DISTRIBUTION ADMINISTRATION OF THE FOOD DISTRIBUTION PROGRAM FOR INDIAN HOUSEHOLDS IN OKLAHOMA § 254.1 General purpose. This part sets the requirement under...

  2. General-Purpose Compression for Efficient Retrieval.

    ERIC Educational Resources Information Center

    Cannane, Adam; Williams, Hugh E.

    2001-01-01

    Discusses compression of databases that reduces space requirements and retrieval times; considers compression of documents in text databases based on semistatic modeling with words; and proposes a scheme for general purpose compression that can be applied to all types of data stored in large collections. (Author/LRW)

  3. 22 CFR 309.1 - General purpose.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Relations PEACE CORPS DEBT COLLECTION General Provisions § 309.1 General purpose. This part prescribes the procedures to be used by the United States Peace Corps (Peace Corps) in the collection and/or disposal of non-tax debts owed to Peace Corps and to the United States. ...

  4. 22 CFR 309.1 - General purpose.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Relations PEACE CORPS DEBT COLLECTION General Provisions § 309.1 General purpose. This part prescribes the procedures to be used by the United States Peace Corps (Peace Corps) in the collection and/or disposal of non-tax debts owed to Peace Corps and to the United States. ...

  5. Field Evaluation of a General Purpose Simulator.

    ERIC Educational Resources Information Center

    Spangenberg, Ronald W.

    The use of a general purpose simulator (GPS) to teach Air Force technicians diagnostic and repair procedures for specialized aircraft radar systems is described. An EC II simulator manufactured by Educational Computer Corporation was adapted to resemble the actual configuration technicians would encounter in the field. Data acquired in the…

  6. 22 CFR 309.1 - General purpose.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Relations PEACE CORPS DEBT COLLECTION General Provisions § 309.1 General purpose. This part prescribes the procedures to be used by the United States Peace Corps (Peace Corps) in the collection and/or disposal of non-tax debts owed to Peace Corps and to the United States....

  7. 22 CFR 309.1 - General purpose.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Relations PEACE CORPS DEBT COLLECTION General Provisions § 309.1 General purpose. This part prescribes the procedures to be used by the United States Peace Corps (Peace Corps) in the collection and/or disposal of non-tax debts owed to Peace Corps and to the United States....

  8. 22 CFR 309.1 - General purpose.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Relations PEACE CORPS DEBT COLLECTION General Provisions § 309.1 General purpose. This part prescribes the procedures to be used by the United States Peace Corps (Peace Corps) in the collection and/or disposal of non-tax debts owed to Peace Corps and to the United States....

  9. 12 CFR 1703.31 - General purposes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false General purposes. 1703.31 Section 1703.31 Banks and Banking OFFICE OF FEDERAL HOUSING ENTERPRISE OVERSIGHT, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT OFHEO ORGANIZATION AND FUNCTIONS RELEASE OF INFORMATION Testimony and Production of Documents in...

  10. 7 CFR 254.1 - General purpose.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... INDIAN HOUSEHOLDS IN OKLAHOMA § 254.1 General purpose. This part sets the requirement under which... service areas in Oklahoma. This part also sets the conditions for administration of the Food Distribution Program by eligible Oklahoma tribes determined capable by the Department. ...

  11. 7 CFR 254.1 - General purpose.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... INDIAN HOUSEHOLDS IN OKLAHOMA § 254.1 General purpose. This part sets the requirement under which... service areas in Oklahoma. This part also sets the conditions for administration of the Food Distribution Program by eligible Oklahoma tribes determined capable by the Department. ...

  12. Insensitive Munitions Development for General Purpose Bombs

    DTIC Science & Technology

    1990-08-01

    combat readiness. There has been a concerted effort by industry and A i r Force explosive development teams t o provide an energetic material w h...Insensitive Munitions Development for General Purpose Bombs 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...house efforts, the Air Force has stimulated commercial industry involvement i n explosives research and development . output from this ef for t has

  13. General-Purpose Graphics-Library Program

    NASA Technical Reports Server (NTRS)

    Rogers, Joseph E.

    1993-01-01

    NASA Device Independent Graphics Library (NASADIG) computer program is general-purpose graphics-library program for use with many computer-based-engineering and management application programs. Software offers many features providing user with flexibility in creating graphics. Includes two- and three-dimensional plotting, splines and polynomial interpolation, area blanking control, multiple log/linear axes, legends and text control, curve-thickness control, and multiple text fonts. Written in ANSI FORTRAN 77.

  14. General-Purpose Graphics-Library Program

    NASA Technical Reports Server (NTRS)

    Rogers, Joseph E.

    1993-01-01

    NASA Device Independent Graphics Library (NASADIG) computer program is general-purpose graphics-library program for use with many computer-based-engineering and management application programs. Software offers many features providing user with flexibility in creating graphics. Includes two- and three-dimensional plotting, splines and polynomial interpolation, area blanking control, multiple log/linear axes, legends and text control, curve-thickness control, and multiple text fonts. Written in ANSI FORTRAN 77.

  15. Deictic primitives for general purpose navigation

    NASA Technical Reports Server (NTRS)

    Crismann, Jill D.

    1994-01-01

    A visually-based deictic primative used as an elementary command set for general purpose navigation was investigated. It was shown that a simple 'follow your eyes' scenario is sufficient for tracking a moving target. Limitations of velocity, acceleration, and modeling of the response of the mechanical systems were enforced. Realistic paths of the robots were produced during the simulation. Scientists could remotely command a planetary rover to go to a particular rock formation that may be interesting. Similarly an expert at plant maintenance could obtain diagnostic information remotely by using deictic primitives on a mobile are used in the deictic primitives, we could imagine that the exact same control software could be used for all of these applications.

  16. General-Purpose Software For Computer Graphics

    NASA Technical Reports Server (NTRS)

    Rogers, Joseph E.

    1992-01-01

    NASA Device Independent Graphics Library (NASADIG) is general-purpose computer-graphics package for computer-based engineering and management applications which gives opportunity to translate data into effective graphical displays for presentation. Features include two- and three-dimensional plotting, spline and polynomial interpolation, control of blanking of areas, multiple log and/or linear axes, control of legends and text, control of thicknesses of curves, and multiple text fonts. Included are subroutines for definition of areas and axes of plots; setup and display of text; blanking of areas; setup of style, interpolation, and plotting of lines; control of patterns and of shading of colors; control of legends, blocks of text, and characters; initialization of devices; and setting of mixed alphabets. Written in FORTRAN 77.

  17. General-Purpose Software For Computer Graphics

    NASA Technical Reports Server (NTRS)

    Rogers, Joseph E.

    1992-01-01

    NASA Device Independent Graphics Library (NASADIG) is general-purpose computer-graphics package for computer-based engineering and management applications which gives opportunity to translate data into effective graphical displays for presentation. Features include two- and three-dimensional plotting, spline and polynomial interpolation, control of blanking of areas, multiple log and/or linear axes, control of legends and text, control of thicknesses of curves, and multiple text fonts. Included are subroutines for definition of areas and axes of plots; setup and display of text; blanking of areas; setup of style, interpolation, and plotting of lines; control of patterns and of shading of colors; control of legends, blocks of text, and characters; initialization of devices; and setting of mixed alphabets. Written in FORTRAN 77.

  18. General purpose optimization software for engineering design

    NASA Technical Reports Server (NTRS)

    Vanderplaats, G. N.

    1990-01-01

    The author has developed several general purpose optimization programs over the past twenty years. The earlier programs were developed as research codes and served that purpose reasonably well. However, in taking the formal step from research to industrial application programs, several important lessons have been learned. Among these are the importance of clear documentation, immediate user support, and consistent maintenance. Most important has been the issue of providing software that gives a good, or at least acceptable, design at minimum computational cost. Here, the basic issues developing optimization software for industrial applications are outlined and issues of convergence rate, reliability, and relative minima are discussed. Considerable feedback has been received from users, and new software is being developed to respond to identified needs. The basic capabilities of this software are outlined. A major motivation for the development of commercial grade software is ease of use and flexibility, and these issues are discussed with reference to general multidisciplinary applications. It is concluded that design productivity can be significantly enhanced by the more widespread use of optimization as an everyday design tool.

  19. General-purpose abductive algorithm for interpretation

    NASA Astrophysics Data System (ADS)

    Fox, Richard K.; Hartigan, Julie

    1996-11-01

    Abduction, inference to the best explanation, is an information-processing task that is useful for solving interpretation problems such as diagnosis, medical test analysis, legal reasoning, theory evaluation, and perception. The task is a generative one in which an explanation comprising of domain hypotheses is assembled and used to account for given findings. The explanation is taken to be an interpretation as to why the findings have arisen within the given situation. Research in abduction has led to the development of a general-purpose computational strategy which has been demonstrated on all of the above types of problems. This abduction strategy can be performed in layers so that different types of knowledge can come together in deriving an explanation at different levels of description. Further, the abduction strategy is tractable and offers a very useful tradeoff between confidence in the explanation and completeness of the explanation. This paper will describe this computational strategy for abduction and demonstrate its usefulness towards perceptual problems by examining problem-solving systems in speech recognition and natural language understanding.

  20. AEROPLT: A versatile general purpose plot program

    SciTech Connect

    Larson, D.E.; Fuentes, M.K.

    1989-12-01

    AEROPLT is an interactive, user-friendly, general purpose plot code for plotting tabular data from multiple files. This DISSPLA-based code is convenient and easy to use while permitting great flexibility for users who want to customize their plots. A series of questions leads the user through the program and permits a return to specific portions of the code for plot refinement. Multidevice capability permits the user to plot on the terminal, write to a file for hardcopy plots, or do both simultaneously. An easily modified Setup File is used to store the terminal and hardcopy type codes, plot and text dimensions, and default plot specifications. Parameters for individual plots are written to a Restart File which can easily be edited to change subsequent plots. Additional capabilities are: color plots; a convenient method (similar to TEX) to implement all DISSPLA fonts, character sets, and math alphabets; superscripts, subscripts, underline, and italicize; and plots of the results of mathematical functions of the input data. 12 figs., 21 tabs.

  1. General-purpose monitoring during speech production.

    PubMed

    Riès, Stéphanie; Janssen, Niels; Dufau, Stéphane; Alario, F-Xavier; Burle, Borís

    2011-06-01

    The concept of "monitoring" refers to our ability to control our actions on-line. Monitoring involved in speech production is often described in psycholinguistic models as an inherent part of the language system. We probed the specificity of speech monitoring in two psycholinguistic experiments where electroencephalographic activities were recorded. Our focus was on a component previously reported in nonlinguistic manual tasks and interpreted as a marker of monitoring processes. The error negativity (Ne, or error-related negativity), thought to originate in medial frontal areas, peaks shortly after erroneous responses. A component of seemingly comparable properties has been reported, after errors, in tasks requiring access to linguistic knowledge (e.g., speech production), compatible with a generic error-detection process. However, in contrast to its original name, advanced processing methods later revealed that this component is also present after correct responses in visuomotor tasks. Here, we reported the observation of the same negativity after correct responses across output modalities (manual and vocal responses). This indicates that, in language production too, the Ne reflects on-line response monitoring rather than error detection specifically. Furthermore, the temporal properties of the Ne suggest that this monitoring mechanism is engaged before any auditory feedback. The convergence of our findings with those obtained with nonlinguistic tasks suggests that at least part of the monitoring involved in speech production is subtended by a general-purpose mechanism.

  2. Camouflage Study of General Purpose Small and General Purpose Medium Tents

    DTIC Science & Technology

    1974-12-01

    This study has developed one camouflage pattern for the General Purpose (GP) medium and GP small tent which was submitted for field evaluation by MASSTER. Two additional patterns were developed which are worthy of further evaluation. An overcoloring formulation was developed which is compatible with the FWWMR ( Fire , water , weather and mildew resistant) finish on the cotton fabric used for military tents. Field application techniques were developed for applying the patterns and the overcoloring compounds to

  3. High precision redundant robotic manipulator

    DOEpatents

    Young, Kar-Keung David

    1998-01-01

    A high precision redundant robotic manipulator for overcoming contents imposed by obstacles or imposed by a highly congested work space. One embodiment of the manipulator has four degrees of freedom and another embodiment has seven degreed of freedom. Each of the embodiments utilize a first selective compliant assembly robot arm (SCARA) configuration to provide high stiffness in the vertical plane, a second SCARA configuration to provide high stiffness in the horizontal plane. The seven degree of freedom embodiment also utilizes kinematic redundancy to provide the capability of avoiding obstacles that lie between the base of the manipulator and the end effector or link of the manipulator. These additional three degrees of freedom are added at the wrist link of the manipulator to provide pitch, yaw and roll. The seven degrees of freedom embodiment uses one revolute point per degree of freedom. For each of the revolute joints, a harmonic gear coupled to an electric motor is introduced, and together with properly designed based servo controllers provide an end point repeatability of less than 10 microns.

  4. High precision redundant robotic manipulator

    DOEpatents

    Young, K.K.D.

    1998-09-22

    A high precision redundant robotic manipulator for overcoming contents imposed by obstacles or imposed by a highly congested work space is disclosed. One embodiment of the manipulator has four degrees of freedom and another embodiment has seven degrees of freedom. Each of the embodiments utilize a first selective compliant assembly robot arm (SCARA) configuration to provide high stiffness in the vertical plane, a second SCARA configuration to provide high stiffness in the horizontal plane. The seven degree of freedom embodiment also utilizes kinematic redundancy to provide the capability of avoiding obstacles that lie between the base of the manipulator and the end effector or link of the manipulator. These additional three degrees of freedom are added at the wrist link of the manipulator to provide pitch, yaw and roll. The seven degrees of freedom embodiment uses one revolute point per degree of freedom. For each of the revolute joints, a harmonic gear coupled to an electric motor is introduced, and together with properly designed based servo controllers provide an end point repeatability of less than 10 microns. 3 figs.

  5. 47 CFR 32.6124 - General purpose computers expense.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false General purpose computers expense. 32.6124... General purpose computers expense. This account shall include the costs of personnel whose principal job is the physical operation of general purpose computers and the maintenance of operating systems. This...

  6. 47 CFR 32.6124 - General purpose computers expense.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... application systems and databases for general purpose computers. (See also § 32.6720, General and... 47 Telecommunication 2 2010-10-01 2010-10-01 false General purpose computers expense. 32.6124... General purpose computers expense. This account shall include the costs of personnel whose principal...

  7. 21 CFR 880.6890 - General purpose disinfectants.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false General purpose disinfectants. 880.6890 Section... Miscellaneous Devices § 880.6890 General purpose disinfectants. (a) Identification. A general purpose disinfectant is a germicide intended to process noncritical medical devices and equipment surfaces. A general...

  8. 21 CFR 880.6890 - General purpose disinfectants.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false General purpose disinfectants. 880.6890 Section... Miscellaneous Devices § 880.6890 General purpose disinfectants. (a) Identification. A general purpose disinfectant is a germicide intended to process noncritical medical devices and equipment surfaces. A general...

  9. 21 CFR 880.6890 - General purpose disinfectants.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false General purpose disinfectants. 880.6890 Section... Miscellaneous Devices § 880.6890 General purpose disinfectants. (a) Identification. A general purpose disinfectant is a germicide intended to process noncritical medical devices and equipment surfaces. A general...

  10. 21 CFR 880.6890 - General purpose disinfectants.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false General purpose disinfectants. 880.6890 Section... Miscellaneous Devices § 880.6890 General purpose disinfectants. (a) Identification. A general purpose disinfectant is a germicide intended to process noncritical medical devices and equipment surfaces. A general...

  11. SPIDR, a general-purpose readout system for pixel ASICs

    NASA Astrophysics Data System (ADS)

    van der Heijden, B.; Visser, J.; van Beuzekom, M.; Boterenbrood, H.; Kulis, S.; Munneke, B.; Schreuder, F.

    2017-02-01

    The SPIDR (Speedy PIxel Detector Readout) system is a flexible general-purpose readout platform that can be easily adapted to test and characterize new and existing detector readout ASICs. It is originally designed for the readout of pixel ASICs from the Medipix/Timepix family, but other types of ASICs or front-end circuits can be read out as well. The SPIDR system consists of an FPGA board with memory and various communication interfaces, FPGA firmware, CPU subsystem and an API library on the PC . The FPGA firmware can be adapted to read out other ASICs by re-using IP blocks. The available IP blocks include a UDP packet builder, 1 and 10 Gigabit Ethernet MAC's and a "soft core" CPU . Currently the firmware is targeted at the Xilinx VC707 development board and at a custom board called Compact-SPIDR . The firmware can easily be ported to other Xilinx 7 series and ultra scale FPGAs. The gap between an ASIC and the data acquisition back-end is bridged by the SPIDR system. Using the high pin count VITA 57 FPGA Mezzanine Card (FMC) connector only a simple chip carrier PCB is required. A 1 and a 10 Gigabit Ethernet interface handle the connection to the back-end. These can be used simultaneously for high-speed data and configuration over separate channels. In addition to the FMC connector, configurable inputs and outputs are available for synchronization with other detectors. A high resolution (≈ 27 ps bin size) Time to Digital converter is provided for time stamping events in the detector. The SPIDR system is frequently used as readout for the Medipix3 and Timepix3 ASICs. Using the 10 Gigabit Ethernet interface it is possible to read out a single chip at full bandwidth or up to 12 chips at a reduced rate. Another recent application is the test-bed for the VeloPix ASIC, which is developed for the Vertex Detector of the LHCb experiment. In this case the SPIDR system processes the 20 Gbps scrambled data stream from the VeloPix and distributes it over four 10 Gigabit

  12. 21 CFR 864.4010 - General purpose reagent.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... diagnostic test procedure or system constituting a finished in vitro diagnostic (IVD) test. General purpose reagents are appropriate for combining with one or more than one ASR in producing such systems and include... powered systems. General purpose reagents include cytological preservatives, decalcifying reagents...

  13. Determining PACAF Transportation Alternatives to the General Purpose Vehicle

    DTIC Science & Technology

    2005-03-01

    research, there are two industry defined types of vehicles that will qualify as alternatives to the general purpose vehicle. The first type is the......PACAF TRANSPORTATION ALTERNATIVES TO THE GENERAL PURPOSE VEHICLE THESIS Presented to the Faculty Department of Operational Sciences Graduate

  14. 47 CFR 32.2124 - General purpose computers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false General purpose computers. 32.2124 Section 32.2124 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES UNIFORM... General purpose computers. (a) This account shall include the original cost of computers and...

  15. 47 CFR 32.2124 - General purpose computers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false General purpose computers. 32.2124 Section 32... General purpose computers. (a) This account shall include the original cost of computers and peripheral... cost of computers and their associated peripheral devices associated with switching, network signaling...

  16. 47 CFR 32.2124 - General purpose computers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false General purpose computers. 32.2124 Section 32... General purpose computers. (a) This account shall include the original cost of computers and peripheral... include the cost of computers and their associated peripheral devices associated with switching, network...

  17. 47 CFR 32.2124 - General purpose computers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false General purpose computers. 32.2124 Section 32... General purpose computers. (a) This account shall include the original cost of computers and peripheral... cost of computers and their associated peripheral devices associated with switching, network signaling...

  18. 47 CFR 32.2124 - General purpose computers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false General purpose computers. 32.2124 Section 32... General purpose computers. (a) This account shall include the original cost of computers and peripheral... cost of computers and their associated peripheral devices associated with switching, network signaling...

  19. High precision modeling for fundamental physics experiments

    NASA Astrophysics Data System (ADS)

    Rievers, Benny; Nesemann, Leo; Costea, Adrian; Andres, Michael; Stephan, Ernst P.; Laemmerzahl, Claus

    With growing experimental accuracies and high precision requirements for fundamental physics space missions the needs for accurate numerical modeling techniques are increasing. Motivated by the challenge of length stability in cavities and optical resonators we propose the develop-ment of a high precision modeling tool for the simulation of thermomechanical effects up to a numerical precision of 10-20 . Exemplary calculations for simplified test cases demonstrate the general feasibility of high precision calculations and point out the high complexity of the task. A tool for high precision analysis of complex geometries will have to use new data types, advanced FE solver routines and implement new methods for the evaluation of numerical precision.

  20. 7 CFR 220.1 - General purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AGRICULTURE CHILD NUTRITION PROGRAMS SCHOOL BREAKFAST PROGRAM § 220.1 General purpose and scope. This part... initiate, maintain, or expand nonprofit breakfast programs in schools. [Amdt. 25, 41 FR 34758, Aug. 17...

  1. 7 CFR 2902.37 - General purpose de-icers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... and/or ice, in general use applications by lowering the freezing point of water. Specialized de-icer... Items § 2902.37 General purpose de-icers. (a) Definition. Chemical products (e.g., salt, fluids) that...

  2. 7 CFR 2902.37 - General purpose de-icers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... and/or ice, in general use applications by lowering the freezing point of water. Specialized de-icer... Items § 2902.37 General purpose de-icers. (a) Definition. Chemical products (e.g., salt, fluids) that...

  3. 47 CFR 32.6124 - General purpose computers expense.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... is the physical operation of general purpose computers and the maintenance of operating systems. This... appropriate for the activities being performed. Also excluded are costs incurred in planning and...

  4. 47 CFR 32.6124 - General purpose computers expense.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... is the physical operation of general purpose computers and the maintenance of operating systems. This... appropriate for the activities being performed. Also excluded are costs incurred in planning and...

  5. 47 CFR 32.6124 - General purpose computers expense.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... is the physical operation of general purpose computers and the maintenance of operating systems. This... appropriate for the activities being performed. Also excluded are costs incurred in planning and...

  6. 24. BUILDING NO. 266, GENERAL PURPOSE LABORATORY (ORIGINALLY MAGAZINE FOR ...

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

    24. BUILDING NO. 266, GENERAL PURPOSE LABORATORY (ORIGINALLY MAGAZINE FOR HE 'A' PUMP & CHANGE HOUSE), LOOKING HAST AT NORTHWEST SIDE OF BUILDING. - Picatinny Arsenal, 200 Area, Shell Component Loading, State Route 15 near I-80, Dover, Morris County, NJ

  7. 23. BUILDING NO. 266, GENERAL PURPOSE LABORATORY (ORIGINALLY MAGAZINE FOR ...

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

    23. BUILDING NO. 266, GENERAL PURPOSE LABORATORY (ORIGINALLY MAGAZINE FOR HE 'A' PUMP & CHANGE HOUSE), LOOKING WEST AT NORTHEAST END. - Picatinny Arsenal, 200 Area, Shell Component Loading, State Route 15 near I-80, Dover, Morris County, NJ

  8. 68. BUILDING NO. 3173, GENERAL PURPOSE LABORATORY, LOOKING NORTHWEST AT ...

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

    68. BUILDING NO. 3173, GENERAL PURPOSE LABORATORY, LOOKING NORTHWEST AT SOUTH AND EAST SIDES. BUILT IN 1902 AS A CARPENTER SHOP FOR U.S. NAVY. - Picatinny Arsenal, State Route 15 near I-80, Dover, Morris County, NJ

  9. 22. BUILDING NO. 266, GENERAL PURPOSE LABORATORY (ORIGINALLY MAGAZINE FOR ...

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

    22. BUILDING NO. 266, GENERAL PURPOSE LABORATORY (ORIGINALLY MAGAZINE FOR HE 'A' PUMP & CHANGE HOUSE), LOOKING NORTHEAST AT SOUTHWEST SIDE OF BUILDING. - Picatinny Arsenal, 200 Area, Shell Component Loading, State Route 15 near I-80, Dover, Morris County, NJ

  10. 6. BUILDING NO. 405, GENERAL PURPOSE LABORATORY, LOOKING WEST AT ...

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

    6. BUILDING NO. 405, GENERAL PURPOSE LABORATORY, LOOKING WEST AT NORTHEAST AND SOUTHEAST SIDES. - Picatinny Arsenal, 400 Area, Gun Bag Loading District, State Route 15 near I-80, Dover, Morris County, NJ

  11. The overline{P}{ANDA} detector at FAIR

    NASA Astrophysics Data System (ADS)

    Würschig, Thomas

    2012-05-01

    The PANDA experiment at the future FAIR facility in Darmstadt will perform measurements with antiprotons to explore the physics in the charm quark sector. A state-of-the-art general purpose detector is planned that will allow a variety of complementary studies from high-precision spectroscopy to hypernuclei physics. This article gives a brief introduction to the experiment and the physics program. Main detector requirements are extracted subsequently. Finally, an overview of the instrumentation and the current state of development of the main detector subsystems are given.

  12. The overline{P}{ANDA} detector at FAIR

    NASA Astrophysics Data System (ADS)

    Würschig, Thomas

    The overline{P}{ANDA} experiment at the future FAIR facility in Darmstadt will perform measurements with antiprotons to explore the physics in the charm quark sector. A state-of-the-art general purpose detector is planned that will allow a variety of complementary studies from high-precision spectroscopy to hypernuclei physics. This article gives a brief introduction to the experiment and the physics program. Main detector requirements are extracted subsequently. Finally, an overview of the instrumentation and the current state of development of the main detector subsystems are given.

  13. A general purpose feature extractor for light detection and ranging data.

    PubMed

    Li, Yangming; Olson, Edwin B

    2010-01-01

    Feature extraction is a central step of processing Light Detection and Ranging (LIDAR) data. Existing detectors tend to exploit characteristics of specific environments: corners and lines from indoor (rectilinear) environments, and trees from outdoor environments. While these detectors work well in their intended environments, their performance in different environments can be poor. We describe a general purpose feature detector for both 2D and 3D LIDAR data that is applicable to virtually any environment. Our method adapts classic feature detection methods from the image processing literature, specifically the multi-scale Kanade-Tomasi corner detector. The resulting method is capable of identifying highly stable and repeatable features at a variety of spatial scales without knowledge of environment, and produces principled uncertainty estimates and corner descriptors at same time. We present results on both software simulation and standard datasets, including the 2D Victoria Park and Intel Research Center datasets, and the 3D MIT DARPA Urban Challenge dataset.

  14. A General Purpose Feature Extractor for Light Detection and Ranging Data

    PubMed Central

    Li, Yangming; Olson, Edwin B.

    2010-01-01

    Feature extraction is a central step of processing Light Detection and Ranging (LIDAR) data. Existing detectors tend to exploit characteristics of specific environments: corners and lines from indoor (rectilinear) environments, and trees from outdoor environments. While these detectors work well in their intended environments, their performance in different environments can be poor. We describe a general purpose feature detector for both 2D and 3D LIDAR data that is applicable to virtually any environment. Our method adapts classic feature detection methods from the image processing literature, specifically the multi-scale Kanade-Tomasi corner detector. The resulting method is capable of identifying highly stable and repeatable features at a variety of spatial scales without knowledge of environment, and produces principled uncertainty estimates and corner descriptors at same time. We present results on both software simulation and standard datasets, including the 2D Victoria Park and Intel Research Center datasets, and the 3D MIT DARPA Urban Challenge dataset. PMID:22163474

  15. High precision, rapid laser hole drilling

    DOEpatents

    Chang, Jim J.; Friedman, Herbert W.; Comaskey, Brian J.

    2013-04-02

    A laser system produces a first laser beam for rapidly removing the bulk of material in an area to form a ragged hole. The laser system produces a second laser beam for accurately cleaning up the ragged hole so that the final hole has dimensions of high precision.

  16. High-Precision Photometry with the RCT

    NASA Astrophysics Data System (ADS)

    Everett, M.; Howell, S.; Davis, D.; McGruder, C. H., III; Gelderman, R.; Guinan, E.; Mattox, J. R.; Walter, D. K.

    2003-05-01

    We plan to conduct a high-precision photometric search for transitting extra-solar planets using the refurbished 1.3 m (50 inch) Robotically-Controlled Telescope (RCT) at Kitt Peak. The photometric capabilities and extra-solar planet search strategy for the RCT are discussed. Refurbishment of the RCT has been made possible by NASA grant NAG58762.

  17. High Precision Pressure Measurement with a Funnel

    ERIC Educational Resources Information Center

    Lopez-Arias, T.; Gratton, L. M.; Oss, S.

    2008-01-01

    A simple experimental device for high precision differential pressure measurements is presented. Its working mechanism recalls that of a hydraulic press, where pressure is supplied by insufflating air under a funnel. As an application, we measure air pressure inside a soap bubble. The soap bubble is inflated and connected to a funnel which is…

  18. High precision measurements in crustal dynamic studies

    NASA Technical Reports Server (NTRS)

    Wyatt, F.; Berger, J.

    1984-01-01

    The development of high-precision instrumentation for monitoring benchmark stability and evaluating coseismic strain and tilt signals is reviewed. Laser strainmeter and tilt observations are presented. Examples of coseismic deformation in several geographic locations are given. Evidence suggests that the Earth undergoes elastic response to abrupt faulting.

  19. High Precision Pressure Measurement with a Funnel

    ERIC Educational Resources Information Center

    Lopez-Arias, T.; Gratton, L. M.; Oss, S.

    2008-01-01

    A simple experimental device for high precision differential pressure measurements is presented. Its working mechanism recalls that of a hydraulic press, where pressure is supplied by insufflating air under a funnel. As an application, we measure air pressure inside a soap bubble. The soap bubble is inflated and connected to a funnel which is…

  20. High precision, rapid laser hole drilling

    DOEpatents

    Chang, Jim J.; Friedman, Herbert W.; Comaskey, Brian J.

    2005-03-08

    A laser system produces a first laser beam for rapidly removing the bulk of material in an area to form a ragged hole. The laser system produces a second laser beam for accurately cleaning up the ragged hole so that the final hole has dimensions of high precision.

  1. High precision, rapid laser hole drilling

    DOEpatents

    Chang, Jim J.; Friedman, Herbert W.; Comaskey, Brian J.

    2007-03-20

    A laser system produces a first laser beam for rapidly removing the bulk of material in an area to form a ragged hole. The laser system produces a second laser beam for accurately cleaning up the ragged hole so that the final hole has dimensions of high precision.

  2. 7 CFR 215.1 - General purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SPECIAL MILK PROGRAM FOR CHILDREN § 215.1 General purpose and scope. This part announces the policies and prescribes the general regulations with respect to the Special...

  3. 7 CFR 235.1 - General purpose and scope.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS STATE ADMINISTRATIVE EXPENSE FUNDS § 235.1 General purpose and scope... of section 7 of the Child Nutrition Act of 1966, as amended. It prescribes the methods for...

  4. 7 CFR 235.1 - General purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS STATE ADMINISTRATIVE EXPENSE FUNDS § 235.1 General purpose and scope... of section 7 of the Child Nutrition Act of 1966, as amended. It prescribes the methods for...

  5. 7 CFR 235.1 - General purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS STATE ADMINISTRATIVE EXPENSE FUNDS § 235.1 General purpose and scope... of section 7 of the Child Nutrition Act of 1966, as amended. It prescribes the methods for...

  6. 7 CFR 235.1 - General purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS STATE ADMINISTRATIVE EXPENSE FUNDS § 235.1 General purpose and scope... of section 7 of the Child Nutrition Act of 1966, as amended. It prescribes the methods for...

  7. 7 CFR 215.1 - General purpose and scope.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SPECIAL MILK PROGRAM FOR CHILDREN § 215.1 General purpose and scope. This part announces the policies and prescribes the general regulations with respect to the Special...

  8. 7 CFR 215.1 - General purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SPECIAL MILK PROGRAM FOR CHILDREN § 215.1 General purpose and scope. This part announces the policies and prescribes the general regulations with respect to the Special...

  9. 7 CFR 215.1 - General purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SPECIAL MILK PROGRAM FOR CHILDREN § 215.1 General purpose and scope. This part announces the policies and prescribes the general regulations with respect to the Special...

  10. 7 CFR 235.1 - General purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS STATE ADMINISTRATIVE EXPENSE FUNDS § 235.1 General purpose and scope... of section 7 of the Child Nutrition Act of 1966, as amended. It prescribes the methods for...

  11. 7 CFR 215.1 - General purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SPECIAL MILK PROGRAM FOR CHILDREN § 215.1 General purpose and scope. This part announces the policies and prescribes the general regulations with respect to the Special...

  12. 7 CFR 210.1 - General purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS NATIONAL SCHOOL LUNCH PROGRAM General § 210.1 General purpose and scope... the relationship between proper eating and good health. (b) Scope of the regulations. This part...

  13. 7 CFR 210.1 - General purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS NATIONAL SCHOOL LUNCH PROGRAM General § 210.1 General purpose and scope... the relationship between proper eating and good health. (b) Scope of the regulations. This part...

  14. 7 CFR 227.1 - General purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS NUTRITION EDUCATION AND TRAINING PROGRAM General § 227.1 General purpose and scope. The purpose of these regulations is to implement section 19 of the Child Nutrition Act...

  15. 7 CFR 271.1 - General purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the levels of nutrition among low-income households. Section 2 of the Food Stamp Act of 1977 states... AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION PROGRAM GENERAL INFORMATION AND DEFINITIONS § 271.1 General purpose and scope. (a) Purpose of the food stamp program. The food stamp program is designed to promote...

  16. 7 CFR 271.1 - General purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... the levels of nutrition among low-income households. Section 2 of the Food Stamp Act of 1977 states... AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION PROGRAM GENERAL INFORMATION AND DEFINITIONS § 271.1 General purpose and scope. (a) Purpose of the food stamp program. The food stamp program is designed to promote...

  17. 7 CFR 271.1 - General purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the levels of nutrition among low-income households. Section 2 of the Food Stamp Act of 1977 states... AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION PROGRAM GENERAL INFORMATION AND DEFINITIONS § 271.1 General purpose and scope. (a) Purpose of the food stamp program. The food stamp program is designed to promote...

  18. 21 CFR 880.6890 - General purpose disinfectants.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false General purpose disinfectants. 880.6890 Section 880.6890 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal...

  19. 7 CFR 281.1 - General purpose and scope.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION PROGRAM ADMINISTRATION OF SNAP ON INDIAN RESERVATIONS § 281.1 General purpose and scope. (a) These regulations govern the operation of SNAP on Indian...

  20. 7 CFR 210.1 - General purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS NATIONAL SCHOOL LUNCH PROGRAM General § 210.1 General purpose and scope... the relationship between proper eating and good health. (b) Scope of the regulations. This part sets...

  1. 7 CFR 210.1 - General purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS NATIONAL SCHOOL LUNCH PROGRAM General § 210.1 General purpose and scope... the relationship between proper eating and good health. (b) Scope of the regulations. This part sets...

  2. 7 CFR 210.1 - General purpose and scope.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGRICULTURE CHILD NUTRITION PROGRAMS NATIONAL SCHOOL LUNCH PROGRAM General § 210.1 General purpose and scope. (a) Purpose of the program. Section 2 of the National School Lunch Act (42 U.S.C. 1751), states: “It... expansion of nonprofit school lunch programs.” Pursuant to this act, the Department provides States with...

  3. KEPLER: General purpose 1D multizone hydrodynamics code

    NASA Astrophysics Data System (ADS)

    Weaver, T. A.; Zimmerman, G. B.; Woosley, S. E.

    2017-02-01

    KEPLER is a general purpose stellar evolution/explosion code that incorporates implicit hydrodynamics and a detailed treatment of nuclear burning processes. It has been used to study the complete evolution of massive and supermassive stars, all major classes of supernovae, hydrostatic and explosive nucleosynthesis, and x- and gamma-ray bursts on neutron stars and white dwarfs.

  4. Circuitry selectively limits data storage in general purpose computer

    NASA Technical Reports Server (NTRS)

    Slopper, D. K.

    1969-01-01

    Circuitry limits storage in the memory of a stored program general purpose digital computer by permitting storage or writing to certain, specified areas of memory. The limit register used in the computer is easily set under program control, and the memory block size and position is readily changed to suit each specific program.

  5. 7 CFR 225.1 - General purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SUMMER FOOD SERVICE PROGRAM General § 225.1 General purpose and scope. This part establishes the regulations under which the Secretary will administer a Summer Food Service...

  6. 7 CFR 227.1 - General purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS NUTRITION EDUCATION AND TRAINING PROGRAM General § 227.1 General purpose and scope. The purpose of these regulations is to implement section 19 of the Child Nutrition Act...

  7. 7 CFR 227.1 - General purpose and scope.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS NUTRITION EDUCATION AND TRAINING PROGRAM General § 227.1 General purpose and scope. The purpose of these regulations is to implement section 19 of the Child Nutrition Act...

  8. 7 CFR 227.1 - General purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS NUTRITION EDUCATION AND TRAINING PROGRAM General § 227.1 General purpose and scope. The purpose of these regulations is to implement section 19 of the Child Nutrition Act...

  9. 7 CFR 227.1 - General purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS NUTRITION EDUCATION AND TRAINING PROGRAM General § 227.1 General purpose and scope. The purpose of these regulations is to implement section 19 of the Child Nutrition Act...

  10. 7 CFR 2902.48 - General purpose household cleaners.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AND NEW USES, DEPARTMENT OF AGRICULTURE GUIDELINES FOR DESIGNATING BIOBASED PRODUCTS FOR FEDERAL PROCUREMENT Designated Items § 2902.48 General purpose household cleaners. (a) Definition. Products designed to clean multiple common household surfaces. This designated item does not include products that...

  11. 7 CFR 225.1 - General purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SUMMER FOOD SERVICE PROGRAM General § 225.1 General purpose and scope. This part establishes the regulations under which the Secretary will administer a Summer Food Service...

  12. 7 CFR 225.1 - General purpose and scope.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SUMMER FOOD SERVICE PROGRAM General § 225.1 General purpose and scope. This part establishes the regulations under which the Secretary will administer a Summer Food Service...

  13. 7 CFR 225.1 - General purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SUMMER FOOD SERVICE PROGRAM General § 225.1 General purpose and scope. This part establishes the regulations under which the Secretary will administer a Summer Food Service...

  14. 7 CFR 225.1 - General purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SUMMER FOOD SERVICE PROGRAM General § 225.1 General purpose and scope. This part establishes the regulations under which the Secretary will administer a Summer Food Service...

  15. 22 CFR 211.1 - General purpose and scope; legislation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Section 211.1 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT TRANSFER OF FOOD COMMODITIES FOR FOOD USE IN DISASTER RELIEF, ECONOMIC DEVELOPMENT AND OTHER ASSISTANCE § 211.1 General purpose and scope; legislation. (a) Legislation. The Agricultural Trade Development and Assistance Act of 1954, as amended (Pub...

  16. 22 CFR 211.1 - General purpose and scope; legislation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Section 211.1 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT TRANSFER OF FOOD COMMODITIES FOR FOOD USE IN DISASTER RELIEF, ECONOMIC DEVELOPMENT AND OTHER ASSISTANCE § 211.1 General purpose and scope; legislation. (a) Legislation. The Agricultural Trade Development and Assistance Act of 1954, as amended (Pub...

  17. 22 CFR 211.1 - General purpose and scope; legislation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Section 211.1 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT TRANSFER OF FOOD COMMODITIES FOR FOOD USE IN DISASTER RELIEF, ECONOMIC DEVELOPMENT AND OTHER ASSISTANCE § 211.1 General purpose and scope; legislation. (a) Legislation. The Agricultural Trade Development and Assistance Act of 1954, as amended (Pub...

  18. 7 CFR 2902.48 - General purpose household cleaners.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... formulated for use as disinfectants. Task-specific cleaning products, such as spot and stain removers... AND NEW USES, DEPARTMENT OF AGRICULTURE GUIDELINES FOR DESIGNATING BIOBASED PRODUCTS FOR FEDERAL PROCUREMENT Designated Items § 2902.48 General purpose household cleaners. (a) Definition. Products...

  19. 7 CFR 3201.48 - General purpose household cleaners.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... formulated for use as disinfectants. Task-specific cleaning products, such as spot and stain removers... PROPERTY MANAGEMENT, DEPARTMENT OF AGRICULTURE GUIDELINES FOR DESIGNATING BIOBASED PRODUCTS FOR FEDERAL PROCUREMENT Designated Items § 3201.48 General purpose household cleaners. (a) Definition. Products...

  20. 7 CFR 3201.48 - General purpose household cleaners.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... formulated for use as disinfectants. Task-specific cleaning products, such as spot and stain removers... PROPERTY MANAGEMENT, DEPARTMENT OF AGRICULTURE GUIDELINES FOR DESIGNATING BIOBASED PRODUCTS FOR FEDERAL PROCUREMENT Designated Items § 3201.48 General purpose household cleaners. (a) Definition. Products...

  1. 7 CFR 3201.48 - General purpose household cleaners.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... formulated for use as disinfectants. Task-specific cleaning products, such as spot and stain removers... PROPERTY MANAGEMENT, DEPARTMENT OF AGRICULTURE GUIDELINES FOR DESIGNATING BIOBASED PRODUCTS FOR FEDERAL PROCUREMENT Designated Items § 3201.48 General purpose household cleaners. (a) Definition. Products...

  2. High precision, medium flux rate CZT spectroscopy for coherent scatter imaging

    NASA Astrophysics Data System (ADS)

    Greenberg, Joel A.; Hassan, Mehadi; Brady, David J.; Iniewski, Kris

    2016-05-01

    CZT detectors are primary candidates for many next-generation X-ray imaging systems. These detectors are typically operated in either a high precision, low flux spectroscopy mode or a low precision, high flux photon counting mode. We demonstrate a new detector configuration that enables operation in a high precision, medium flux spectroscopy mode, which opens the potential for a variety of new applications in medical imaging, non-destructive testing and baggage scanning. In particular, we describe the requirements of a coded aperture coherent scattering X-ray system that can perform fast imaging with accurate material discrimination.

  3. Portable high precision pressure transducer system

    NASA Astrophysics Data System (ADS)

    Piper, T. C.; Morgan, J. P.; Marchant, N. J.; Bolton, S. M.

    A high precision pressure transducer system for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank is presented. Since the response of the pressure transducer is temperature sensitive, it is continually housed in a battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on-board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum fluorescent display.

  4. High-Precision Computation and Mathematical Physics

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.

    2008-11-03

    At the present time, IEEE 64-bit floating-point arithmetic is sufficiently accurate for most scientific applications. However, for a rapidly growing body of important scientific computing applications, a higher level of numeric precision is required. Such calculations are facilitated by high-precision software packages that include high-level language translation modules to minimize the conversion effort. This paper presents a survey of recent applications of these techniques and provides some analysis of their numerical requirements. These applications include supernova simulations, climate modeling, planetary orbit calculations, Coulomb n-body atomic systems, scattering amplitudes of quarks, gluons and bosons, nonlinear oscillator theory, Ising theory, quantum field theory and experimental mathematics. We conclude that high-precision arithmetic facilities are now an indispensable component of a modern large-scale scientific computing environment.

  5. Portable high precision pressure transducer system

    DOEpatents

    Piper, Thomas C.; Morgan, John P.; Marchant, Norman J.; Bolton, Steven M.

    1994-01-01

    A high precision pressure transducer system for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank. Since the response of the pressure transducer is temperature sensitive, it is continually housed in an battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum florescent display.

  6. Portable high precision pressure transducer system

    DOEpatents

    Piper, T.C.; Morgan, J.P.; Marchant, N.J.; Bolton, S.M.

    1994-04-26

    A high precision pressure transducer system is described for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank. Since the response of the pressure transducer is temperature sensitive, it is continually housed in an battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum fluorescent display. 2 figures.

  7. Speed Control of General Purpose Engine with Electronic Governor

    NASA Astrophysics Data System (ADS)

    Sawut, Umerujan; Tohti, Gheyret; Takigawa, Buso; Tsuji, Teruo

    This paper presents a general purpose engine speed control system with an electronic governor in order to improve the current system with a mechanical governor which shows unstable characteristics by change of mecanical friction or A/F ratio (Air/Fuel ratio). For the control system above, there are problems that the feedback signal is only a crank angle because of cost and the controlled object is a general purpose engine which is strongly nonlinear. In order to overcome these problems, the system model is shown for the dynamic estimation of the amount of air flow and the robust controller is designed. That is, the proposed system includes the robust sliding-mode controller by the feedback signal of only a crank angle where Genetic Algorithm is applied for the controller design. The simulation and the experiments by MATLAB/Simulink are performed to show the effectiveness of our proposal.

  8. A Small Acoustic Goniometer for General Purpose Research

    PubMed Central

    Pook, Michael L.; Loo, Sin Ming

    2016-01-01

    Understanding acoustic events and monitoring their occurrence is a useful aspect of many research projects. In particular, acoustic goniometry allows researchers to determine the source of an event based solely on the sound it produces. The vast majority of acoustic goniometry research projects used custom hardware targeted to the specific application under test. Unfortunately, due to the wide range of sensing applications, a flexible general purpose hardware/firmware system does not exist for this purpose. This article focuses on the development of such a system which encourages the continued exploration of general purpose hardware/firmware and lowers barriers to research in projects requiring the use of acoustic goniometry. Simulations have been employed to verify system feasibility, and a complete hardware implementation of the acoustic goniometer has been designed and field tested. The results are reported, and suggested areas for improvement and further exploration are discussed. PMID:27136563

  9. A Small Acoustic Goniometer for General Purpose Research.

    PubMed

    Pook, Michael L; Loo, Sin Ming

    2016-04-29

    Understanding acoustic events and monitoring their occurrence is a useful aspect of many research projects. In particular, acoustic goniometry allows researchers to determine the source of an event based solely on the sound it produces. The vast majority of acoustic goniometry research projects used custom hardware targeted to the specific application under test. Unfortunately, due to the wide range of sensing applications, a flexible general purpose hardware/firmware system does not exist for this purpose. This article focuses on the development of such a system which encourages the continued exploration of general purpose hardware/firmware and lowers barriers to research in projects requiring the use of acoustic goniometry. Simulations have been employed to verify system feasibility, and a complete hardware implementation of the acoustic goniometer has been designed and field tested. The results are reported, and suggested areas for improvement and further exploration are discussed.

  10. General-Purpose Serial Interface For Remote Control

    NASA Technical Reports Server (NTRS)

    Busquets, Anthony M.; Gupton, Lawrence E.

    1990-01-01

    Computer controls remote television camera. General-purpose controller developed to serve as interface between host computer and pan/tilt/zoom/focus functions on series of automated video cameras. Interface port based on 8251 programmable communications-interface circuit configured for tristated outputs, and connects controller system to any host computer with RS-232 input/output (I/O) port. Accepts byte-coded data from host, compares them with prestored codes in read-only memory (ROM), and closes or opens appropriate switches. Six output ports control opening and closing of as many as 48 switches. Operator controls remote television camera by speaking commands, in system including general-purpose controller.

  11. High precision neutron inelastic cross section measurements

    NASA Astrophysics Data System (ADS)

    Olacel, A.; Belloni, F.; Borcea, C.; Boromiza, M.; Dessagne, Ph.; Henning, G.; Kerveno, M.; Negret, A.; Nyman, M.; Pirovano, E.; Plompen, A.

    2017-06-01

    High precision neutron inelastic scattering cross section data are very important for the development of the new generation of nuclear reactors (Gen IV). Our experiments, performed using the GELINA neutron source and the GAINS spectrometer of the European Commission Joint Research Center, Geel, produce highly reliable and precise cross section data. We will present the details of the setup and the data analysis technique allowing production of such unique results, and we will show examples of two experimental results.

  12. High-precision arithmetic in mathematical physics

    DOE PAGES

    Bailey, David H.; Borwein, Jonathan M.

    2015-05-12

    For many scientific calculations, particularly those involving empirical data, IEEE 32-bit floating-point arithmetic produces results of sufficient accuracy, while for other applications IEEE 64-bit floating-point is more appropriate. But for some very demanding applications, even higher levels of precision are often required. Furthermore, this article discusses the challenge of high-precision computation, in the context of mathematical physics, and highlights what facilities are required to support future computation, in light of emerging developments in computer architecture.

  13. Simple Design Rules for Spike Neural Network Based General Purpose Networks

    NASA Astrophysics Data System (ADS)

    Roy, Arnab; Schaffer, J. David; Laramee, Craig

    2012-02-01

    It has been much lamented over the past decade that, although spiking neural networks (SNNs) have exciting proven computational properties, there are no design rules for assembling networks for specific purposes. Here we offer design approaches for creating three general purpose networks namely, a temporal pattern (serial channel) detector, sequence detector (parallel channel), and any specific mapping of input to output spike patterns on a serial channel. Central pattern generators are instances of this last design. These design rules are based on synchrony detection which SNNs do so well. Here we also introduce a modification to the basic SRM0 model which not only reduces the computational cost, but also enables us to develop these design rules. We discuss how these designs may be combined into fairly general spatio-temporal pattern detectors. Finally, by adding a capability for feature discovery/extraction, we envision an approach to learning spatio-temporal pattern classifiers.

  14. The parser generator as a general purpose tool

    NASA Technical Reports Server (NTRS)

    Noonan, R. E.; Collins, W. R.

    1985-01-01

    The parser generator has proven to be an extremely useful, general purpose tool. It can be used effectively by programmers having only a knowledge of grammars and no training at all in the theory of formal parsing. Some of the application areas for which a table-driven parser can be used include interactive, query languages, menu systems, translators, and programming support tools. Each of these is illustrated by an example grammar.

  15. New Generation General Purpose Computer (GPC) compact IBM unit

    NASA Technical Reports Server (NTRS)

    1991-01-01

    New Generation General Purpose Computer (GPC) compact IBM unit replaces a two-unit earlier generation computer. The new IBM unit is documented in table top views alone (S91-26867, S91-26868), with the onboard equipment it supports including the flight deck CRT screen and keypad (S91-26866), and next to the two earlier versions it replaces (S91-26869).

  16. Special or general-purpose hardware for Prolog: A comparison

    SciTech Connect

    Borriello, G.; Cherenson, A.; Danzig, P.; Nelson, M.

    1987-01-01

    This study compares the performance of executing Prolog code on the Berkeley PLM processor (a special-purpose CISC architecture) and the Berkeley SPUR processor (a general-purpose RISC architecture with tagged data). Fourteen standard benchmark programs were run on both the PLM and SPUR simulators. The two implementations were compared with regard to static and dynamic program size, execution speed, and cache performance. The simulated memory system included a direct-mapped mixed instruction and data cache.

  17. Space shuttle general purpose computers (GPCs) (current and future versions)

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Current and future versions of general purpose computers (GPCs) for space shuttle orbiters are represented in this frame. The two boxes on the left (AP101B) represent the current GPC configuration, with the input-output processor at far left and the central processing unit (CPU) at its side. The upgraded version combines both elements in a single unit (far right, AP101S).

  18. Linear equations in general purpose codes for stiff ODEs

    SciTech Connect

    Shampine, L. F.

    1980-02-01

    It is noted that it is possible to improve significantly the handling of linear problems in a general-purpose code with very little trouble to the user or change to the code. In such situations analytical evaluation of the Jacobian is a lot cheaper than numerical differencing. A slight change in the point at which the Jacobian is evaluated results in a more accurate Jacobian in linear problems. (RWR)

  19. The Architecture of Newton, a General-Purpose Dynamics Simulator

    DTIC Science & Technology

    1989-01-01

    11 N The Architecture of Newton, a General-Purpose Dynamics 0 Simulator OTIC James F. Cremer ELECTE A. James Stewart JUL 141989f l Computer Science...173SS, ONR grant N00t4.SK-0281 and DARPA grant N0014-OOK.0S91 Support for James Stewart is provided in part by U.S. Army Math-4.3 Control matica Sciences

  20. Development of General Purpose Data Acquisition Shell (GPDAS)

    SciTech Connect

    Chung, Y.; Kim, K.

    1995-07-01

    This note is intended as an abbreviated introduction to the concept and the structure of General Purpose Data Acquisitions Shell (GPDAS) and assumes the reader has a certain level of familiarity with programming in general. The structure of the following sections consists of brief explanations of the concepts and commands of GPDAS, followed by several examples. Some of these are tabulated in the appendices at the end of this note.

  1. Space shuttle general purpose computers (GPCs) (current and future versions)

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Current and future versions of general purpose computers (GPCs) for space shuttle orbiters are represented in this frame. The two boxes on the left (AP101B) represent the current GPC configuration, with the input-output processor at far left and the central processing unit (CPU) at its side. The upgraded version combines both elements in a single unit (far right, AP101S).

  2. 15KW General Purpose Power Conditioner (Frequency Changer).

    DTIC Science & Technology

    1980-09-26

    RD-0145 523 15KW GENERAL PURPOSE POWER CONDITIONER (FREQUENCY in3 CHRNGER)(U) GENERAL MOTORS CORP GOLETA CA DELCO ELECTRONICS DIY 26 SEP 80 R80-122...Virginia L * Delco Electronics General Motors Corporation - Santa Barbara Operations Santa Barbara, California D=YtTRO? STATEMENT App eovi 1w public...ELECTROtICS OVIION. SANTA IARUARA OPERATIONS 0 GENERAL MOTORS CORPORATION TABLE OF CONTENTS Section Title Page Er. I PURPOSE OF TESTS 1-1 H DESCRIPTION OF

  3. New Generation General Purpose Computer (GPC) compact IBM unit

    NASA Technical Reports Server (NTRS)

    1991-01-01

    New Generation General Purpose Computer (GPC) compact IBM unit replaces a two-unit earlier generation computer. The new IBM unit is documented in table top views alone (S91-26867, S91-26868), with the onboard equipment it supports including the flight deck CRT screen and keypad (S91-26866), and next to the two earlier versions it replaces (S91-26869).

  4. Installation of new Generation General Purpose Computer (GPC) compact unit

    NASA Technical Reports Server (NTRS)

    1991-01-01

    In the Kennedy Space Center's (KSC's) Orbiter Processing Facility (OPF) high bay 2, Spacecraft Electronics technician Ed Carter (right), wearing clean suit, prepares for (26864) and installs (26865) the new Generation General Purpose Computer (GPC) compact IBM unit in Atlantis', Orbiter Vehicle (OV) 104's, middeck avionics bay as Orbiter Systems Quality Control technician Doug Snider looks on. Both men work for NASA contractor Lockheed Space Operations Company. All three orbiters are being outfitted with the compact IBM unit, which replaces a two-unit earlier generation computer.

  5. The architecture of Newton, a general-purpose dynamics simulator

    NASA Technical Reports Server (NTRS)

    Cremer, James F.; Stewart, A. James

    1989-01-01

    The architecture for Newton, a general-purpose system for simulating the dynamics of complex physical objects, is described. The system automatically formulates and analyzes equations of motion, and performs automatic modification of this system equations when necessitated by changes in kinematic relationships between objects. Impact and temporary contact are handled, although only using simple models. User-directed influence of simulations is achieved using Newton's module, which can be used to experiment with the control of many-degree-of-freedom articulated objects.

  6. A general-purpose optimization program for engineering design

    NASA Technical Reports Server (NTRS)

    Vanderplaats, G. N.; Sugimoto, H.

    1986-01-01

    A new general-purpose optimization program for engineering design is described. ADS (Automated Design Synthesis) is a FORTRAN program for nonlinear constrained (or unconstrained) function minimization. The optimization process is segmented into three levels: Strategy, Optimizer, and One-dimensional search. At each level, several options are available so that a total of nearly 100 possible combinations can be created. An example of available combinations is the Augmented Lagrange Multiplier method, using the BFGS variable metric unconstrained minimization together with polynomial interpolation for the one-dimensional search.

  7. The architecture of Newton, a general-purpose dynamics simulator

    NASA Technical Reports Server (NTRS)

    Cremer, James F.; Stewart, A. James

    1989-01-01

    The architecture for Newton, a general-purpose system for simulating the dynamics of complex physical objects, is described. The system automatically formulates and analyzes equations of motion, and performs automatic modification of this system equations when necessitated by changes in kinematic relationships between objects. Impact and temporary contact are handled, although only using simple models. User-directed influence of simulations is achieved using Newton's module, which can be used to experiment with the control of many-degree-of-freedom articulated objects.

  8. Research about the high precision temperature measurement

    NASA Astrophysics Data System (ADS)

    Lin, J.; Yu, J.; Zhu, X.; Zeng, Z.; Deng, Y.

    2012-12-01

    High precision temperature control system is one of most important support conditions for tunable birefringent filter.As the first step,we researched some high precision temperature measurement methods for it. Firstly, circuits with a 24 bit ADC as the sensor's reader were carefully designed; Secondly, an ARM porcessor is used as the centrol processing unit, it provides sufficient reading and procesing ability; Thirdly, three kinds of sensors, PT100, Dale 01T1002-5 thermistor, Wheatstone bridge(constructed by pure copper and manganin) as the senor of the temperature were tested respectively. The resolution of the measurement with these three kinds of sensors are all better than 0.001 that's enough for 0.01 stability temperature control. Comparatively, Dale 01T1002-5 thermistor could get the most accurate temperature of the key point, Wheatstone bridge could get the most accurate mean temperature of the whole layer, both of them will be used in our futrue temperature controll system.

  9. Development and application of a general purpose ambulatory monitor.

    PubMed

    Petley, G W; Clitheroe, S; Clewlow, F; Deakin, C D; Chauhan, A J

    1998-01-01

    This paper details the development and application of a multi-channel, general purpose, lightweight, portable monitor. The monitor is constructed with separate analogue and digital circuitry so that a dedicated analogue board may be developed for each new application with the same general purpose digital board, the latter requiring only changes to the firmware. At the heart of the digital circuit is an Arizona Microchip PIC 16C64 microcontroller, which can communicate with a computer via a serial port and perform both simple and relatively complex data analysis prior to storing data in memory. The low-power design enables the circuit to operate for potentially longer than a week on one set of batteries. Designed with medical applications in mind, preliminary data from three studies utilising the monitor are described. These include measurements of bladder pressure, personal exposure to pollutant gases and body temperature. The studies demonstrate the system's versatility in a variety of investigations requiring different signal processing and sampling protocols. It is hoped that, in the future, this ambulatory device will contribute to the diagnosis, treatment and understanding of a wide variety of disease conditions.

  10. A General Purpose Stacking Technique to Analyze Low Brightness Signal

    NASA Astrophysics Data System (ADS)

    Wavle, Daniel; Leroy, Adam K.; Donovan Meyer, Jennifer

    2015-01-01

    We present an implementation of a general purpose stacking technique in which the detections of bright emission lines are used as priors to analyze low-brightness signal. We demonstrate the use of the technique on ALMA observations of the nuclear region of the nearby galaxy NGC 253 but emphasize its general applicability to a wide class of problems. The conceptual basis for the technique is to use closely associated brighter lines as priors to establish the local velocity (and potentially velocity profile) of a faint line. With this prior, the faint line can be coherently averaged by assuming that it shares a mean velocity with the bright prior. The coherent spectral averaging allows one to more clearly distinguish real astronomical signals from systematic effects, unstable baselines, or imaging artifacts. In our example application, we apply the technique to measure the intensity of faint isotopologues of dense gas tracers in NGC 253, lines that are otherwise hard to distinguish from the noise. The implementation of the code is intended for release as a general purpose cube analysis tool compatible with other astronomical python packages.

  11. High precision wavelength meter with Fabry-Perot optics

    NASA Astrophysics Data System (ADS)

    Konishi, N.; Suzuki, T.; Taira, Y.; Kato, H.; Kasuya, T.

    1981-07-01

    A high precision wavelength meter in the visible is described, which is based on a Fabry-Perot interferometer with several etalons of different resolution. The interference fringe pattern projected on a photo-diode array detector is computationally processed to give a stepwise refinement of the wavelength value to any adjusted accuracy. The present model intends to provide digital and real-time values of high precision wavelength for dye-laser spectroscopy, and to serve as a monitor or as a pilot for wavelength control of a dye-laser source of nanosecond pulses. The model is, therefore, designed with particular emphasis on its short-pulse capability and on-line mode of operation as well as on its high sensitivity and resolution. Some arrangements of essential necessity are involved therein, such as to avoid an errorneous wavelength readout for a noisy incidence of pulsed field. The ultimate accuracy of wavelength measurement is prescribed by the resolving power of the thickest etalon employed. As applied to the pulsed source, the model determines the wavelength to the accuracy of ±one part in 107 for even a single shot nanosecond incidence of a fraction of μJ energy. The design and performance are described in connection to pulsed dye-laser incidence.

  12. High precision tracking method for solar telescopes

    NASA Astrophysics Data System (ADS)

    Guo, Jingjing; Yang, Yunfei; Feng, Song; Ji, Kanfan; Lin, Jiaben; Zeng, Zhen; Wang, Bingxiang

    2016-07-01

    A high-precision real-time tracking method for solar telescopes was introduced in this paper based on the barycenter of full-disk solar images algorithm. To make sure the calculation was accurate and reliable, a series of strictly logic limits were set, such as setting gray threshold, judging the displacement of the barycenter and measuring the deviation from a perfect disk. A closed-loop control system was designed in the method. We located the barycenter of the full-disk images which recorded by large array CCD image sensor in real time and eliminate noise caused by bad weather, such as clouds and fog. The displacement of the barycenter was analyzed and transferred into control signal drove the motor to adjust the axis of telescope. An Ethernet interface was also provided for remote control. In the observation, the precision of this new method was better than 1″/30 minutes.

  13. High precision phase-shifting electron holography

    PubMed

    Yamamoto; Kawajiri; Tanji; Hibino; Hirayama

    2000-01-01

    Today's information-oriented society requires high density and high quality magnetic recording media. The quantitative observation of fine magnetic structures by electron holography is greatly anticipated in the development of such new recording materials. However, the magnetic fields around particles <50 nm have not been observed, because the fields are too weak to observe in the usual way. Here we present a highly precise phase measurement technique: improved phase-shifting electron holography. Using this method, the electric field around a charged polystyrene latex particle (100 nm in diameter) and the magnetic field around iron particles (30 nm in diameter) are observed precisely. A precision of the reconstructed phase image of 2pi/300 rad is achieved in the image of the latex particle.

  14. High precision radial velocities with GIANO spectra

    NASA Astrophysics Data System (ADS)

    Carleo, I.; Sanna, N.; Gratton, R.; Benatti, S.; Bonavita, M.; Oliva, E.; Origlia, L.; Desidera, S.; Claudi, R.; Sissa, E.

    2016-06-01

    Radial velocities (RV) measured from near-infrared (NIR) spectra are a potentially excellent tool to search for extrasolar planets around cool or active stars. High resolution infrared (IR) spectrographs now available are reaching the high precision of visible instruments, with a constant improvement over time. GIANO is an infrared echelle spectrograph at the Telescopio Nazionale Galileo (TNG) and it is a powerful tool to provide high resolution spectra for accurate RV measurements of exoplanets and for chemical and dynamical studies of stellar or extragalactic objects. No other high spectral resolution IR instrument has GIANO's capability to cover the entire NIR wavelength range (0.95-2.45 μm) in a single exposure. In this paper we describe the ensemble of procedures that we have developed to measure high precision RVs on GIANO spectra acquired during the Science Verification (SV) run, using the telluric lines as wavelength reference. We used the Cross Correlation Function (CCF) method to determine the velocity for both the star and the telluric lines. For this purpose, we constructed two suitable digital masks that include about 2000 stellar lines, and a similar number of telluric lines. The method is applied to various targets with different spectral type, from K2V to M8 stars. We reached different precisions mainly depending on the H-magnitudes: for H ˜ 5 we obtain an rms scatter of ˜ 10 m s-1, while for H ˜ 9 the standard deviation increases to ˜ 50 ÷ 80 m s-1. The corresponding theoretical error expectations are ˜ 4 m s-1 and 30 m s-1, respectively. Finally we provide the RVs measured with our procedure for the targets observed during GIANO Science Verification.

  15. General purpose multiplexing device for cryogenic microwave systems

    NASA Astrophysics Data System (ADS)

    Chapman, Benjamin J.; Moores, Bradley A.; Rosenthal, Eric I.; Kerckhoff, Joseph; Lehnert, K. W.

    2016-05-01

    We introduce and experimentally characterize a general purpose device for signal processing in circuit quantum electrodynamics systems. The device is a broadband two-port microwave circuit element with three modes of operation: it can transmit, reflect, or invert incident signals between 4 and 8 GHz. This property makes it a versatile tool for lossless signal processing at cryogenic temperatures. In particular, rapid switching (≤ 15 ns ) between these operation modes enables several multiplexing readout protocols for superconducting qubits. We report the device's performance in a two-channel code domain multiplexing demonstration. The multiplexed data are recovered with fast readout times (up to 400 ns ) and infidelities ≤ 10-2 for probe powers ≥ 7 fW , in agreement with the expectation for binary signaling with Gaussian noise.

  16. Toward a General-Purpose Heterogeneous Ensemble for Pattern Classification.

    PubMed

    Nanni, Loris; Brahnam, Sheryl; Ghidoni, Stefano; Lumini, Alessandra

    2015-01-01

    We perform an extensive study of the performance of different classification approaches on twenty-five datasets (fourteen image datasets and eleven UCI data mining datasets). The aim is to find General-Purpose (GP) heterogeneous ensembles (requiring little to no parameter tuning) that perform competitively across multiple datasets. The state-of-the-art classifiers examined in this study include the support vector machine, Gaussian process classifiers, random subspace of adaboost, random subspace of rotation boosting, and deep learning classifiers. We demonstrate that a heterogeneous ensemble based on the simple fusion by sum rule of different classifiers performs consistently well across all twenty-five datasets. The most important result of our investigation is demonstrating that some very recent approaches, including the heterogeneous ensemble we propose in this paper, are capable of outperforming an SVM classifier (implemented with LibSVM), even when both kernel selection and SVM parameters are carefully tuned for each dataset.

  17. Using a cognitive architecture for general purpose service robot control

    NASA Astrophysics Data System (ADS)

    Puigbo, Jordi-Ysard; Pumarola, Albert; Angulo, Cecilio; Tellez, Ricardo

    2015-04-01

    A humanoid service robot equipped with a set of simple action skills including navigating, grasping, recognising objects or people, among others, is considered in this paper. By using those skills the robot should complete a voice command expressed in natural language encoding a complex task (defined as the concatenation of a number of those basic skills). As a main feature, no traditional planner has been used to decide skills to be activated, as well as in which sequence. Instead, the SOAR cognitive architecture acts as the reasoner by selecting which action the robot should complete, addressing it towards the goal. Our proposal allows to include new goals for the robot just by adding new skills (without the need to encode new plans). The proposed architecture has been tested on a human-sized humanoid robot, REEM, acting as a general purpose service robot.

  18. ADS-1 - A new general-purpose optimization program

    NASA Technical Reports Server (NTRS)

    Vanderplaats, G. N.; Sprague, C. M.; Sugimoto, H.

    1983-01-01

    Today, numerous programs are available which may be coupled with finite element analysis or other analysis techniques to perform the optimization function in the solution of structural synthesis problems. However, most of these codes include only one or two algorithms and many have not been tested on problems of significant size and complexity. There is, therefore, a need for a reliable, general-purpose, publicly available code, containing a variety of modern algorithms for use in structural synthesis as well as general engineering design. The ADS-1 program (Automated Design Synthesis: Version 1) was written in response to this need. The present investigation has the objective to present the capabilities of the ADS program and to demonstrate its application to structural synthesis. The ADS program solves the general nonlinear constrained optimization problem in the standard form. At each level of the optimization process, several options are available.

  19. CRUSH TESTING OF 9977 GENERAL PURPOSE FISSILE PACKAGINGS

    SciTech Connect

    Smith, A.

    2010-07-28

    The 9977 General Purpose Fissile Package (GPFP) was designed in response to the adoption of the crush test requirement in the US regulations for packages for radioactive materials (10 CFR 71). This presentation on crush testing of the 9977 GPFP Reviews origins of Crush Test Requirements and implementation of crush test requirements in 10 CFR 71. SANDIA testing performed to support the rule making is reviewed. The differences in practice, on the part of the US Department of Energy from those required by the NRC for commercial purposes, are explained. The design features incorporated into the 9977 GPFP to enable it to withstand the crush test and the crush tests performed on the 9977 are described. Lessons learned from crush testing of GPFP packagings are given.

  20. Toward a General-Purpose Heterogeneous Ensemble for Pattern Classification

    PubMed Central

    Nanni, Loris; Brahnam, Sheryl; Ghidoni, Stefano; Lumini, Alessandra

    2015-01-01

    We perform an extensive study of the performance of different classification approaches on twenty-five datasets (fourteen image datasets and eleven UCI data mining datasets). The aim is to find General-Purpose (GP) heterogeneous ensembles (requiring little to no parameter tuning) that perform competitively across multiple datasets. The state-of-the-art classifiers examined in this study include the support vector machine, Gaussian process classifiers, random subspace of adaboost, random subspace of rotation boosting, and deep learning classifiers. We demonstrate that a heterogeneous ensemble based on the simple fusion by sum rule of different classifiers performs consistently well across all twenty-five datasets. The most important result of our investigation is demonstrating that some very recent approaches, including the heterogeneous ensemble we propose in this paper, are capable of outperforming an SVM classifier (implemented with LibSVM), even when both kernel selection and SVM parameters are carefully tuned for each dataset. PMID:26413089

  1. User's manual SIG: a general-purpose signal processing program

    SciTech Connect

    Lager, D.; Azevedo, S.

    1983-10-25

    SIG is a general-purpose signal processing, analysis, and display program. Its main purpose is to perform manipulations on time- and frequency-domain signals. However, it has been designed to ultimately accommodate other representations for data such as multiplexed signals and complex matrices. Many of the basic operations one would perform on digitized data are contained in the core SIG package. Out of these core commands, more powerful signal processing algorithms may be built. Many different operations on time- and frequency-domain signals can be performed by SIG. They include operations on the samples of a signal, such as adding a scalar to each sample, operations on the entire signal such as digital filtering, and operations on two or more signals such as adding two signals. Signals may be simulated, such as a pulse train or a random waveform. Graphics operations display signals and spectra.

  2. SIG: a general-purpose signal processing program

    SciTech Connect

    Lager, D.; Azevedo, S.

    1986-02-01

    SIG is a general-purpose signal processing, analysis, and display program. Its main purpose is to perform manipulations on time- and frequency-domain signals. It also accommodates other representations for data such as transfer function polynomials. Signal processing operations include digital filtering, auto/cross spectral density, transfer function/impulse response, convolution, Fourier transform, and inverse Fourier transform. Graphical operations provide display of signals and spectra, including plotting, cursor zoom, families of curves, and multiple viewport plots. SIG provides two user interfaces with a menu mode for occasional users and a command mode for more experienced users. Capability exits for multiple commands per line, command files with arguments, commenting lines, defining commands, automatic execution for each item in a repeat sequence, etc. SIG is presently available for VAX(VMS), VAX (BERKELEY 4.2 UNIX), SUN (BERKELEY 4.2 UNIX), DEC-20 (TOPS-20), LSI-11/23 (TSX), and DEC PRO 350 (TSX). 4 refs., 2 figs.

  3. A Chemical Containment Model for the General Purpose Work Station

    NASA Technical Reports Server (NTRS)

    Flippen, Alexis A.; Schmidt, Gregory K.

    1994-01-01

    Contamination control is a critical safety requirement imposed on experiments flying on board the Spacelab. The General Purpose Work Station, a Spacelab support facility used for life sciences space flight experiments, is designed to remove volatile compounds from its internal airpath and thereby minimize contamination of the Spacelab. This is accomplished through the use of a large, multi-stage filter known as the Trace Contaminant Control System. Many experiments planned for the Spacelab require the use of toxic, volatile fixatives in order to preserve specimens prior to postflight analysis. The NASA-Ames Research Center SLS-2 payload, in particular, necessitated the use of several toxic, volatile compounds in order to accomplish the many inflight experiment objectives of this mission. A model was developed based on earlier theories and calculations which provides conservative predictions of the resultant concentrations of these compounds given various spill scenarios. This paper describes the development and application of this model.

  4. General Purpose Computer (GPC) to GPC systems interface description

    NASA Technical Reports Server (NTRS)

    Breyer, B. C.

    1976-01-01

    The General Purpose Computer (GPC) 'subsystem' of the Orbiter Data Processing System was described. Two interface areas are discussed. One is the area of GPC intraconnections and intracommunications involving the hardware/software interface between the Central Processing Unit (CPU) and the Input/Output Processor (IOP). The other is the area of GPC interconnections and intercommunications and involves the hardware/software interface between the five Orbiter GPC's. Based on the detailed GPC interface given, it is felt that the basic CPU to IOP interface and the GPC to GPC interface have the potential for trouble free operation. However, due to the complexity of the interface and the criticality of GPC synchronization to overall avionics performance, the GPC to GPC interface should be carefully evaluated when attempting to resolve test anomalies that may involve GPC timing and synchronization errors.

  5. High precision Woelter optic calibration facility

    SciTech Connect

    Morales, R.I.; Remington, B.A.; Schwinn, T. )

    1995-01-01

    We have developed an off-line facility for very precise characterization of the reflectance and spatial resolution of the grazing incidence Woelter type I x-ray optics used at Nova. The primary component of the facility is a new, very versatile, high brightness x-ray source consisting of a focused DC electron beam incident onto a precision manipulated target-pinhole array. The data are recorded with a selection of detectors. For imaging measurements we use direct exposure x-ray film modules or an x-ray charge-coupled device camera. For energy-resolved reflectance measurements, we use lithium drifted silicon detectors and a proportional counter. An [ital in] [ital situ] laser alignment system allows precise location and rapid periodic alignment verification of the x-ray point source, the statically mounted Woelter optic, and the chosen detector.

  6. High precision Woelter optic calibration facility

    SciTech Connect

    Morales, R.I.; Remington, B.A.; Schwinn, T.

    1994-05-02

    We have developed an off-line facility for very precise characterization of the reflectance and spatial resolution of the grazing incidence Woelter Type 1 x-ray optics used at Nova. The primary component of the facility is a high brightness, ``point`` x-ray source consisting of a focussed DC electron beam incident onto a precision manipulated target/pinhole array. The data are recorded with a selection of detectors. For imaging measurements we use direct exposure x-ray film modules or an x-ray CCD camera. For energy-resolved reflectance measurements, we use lithium drifted silicon detectors and a proportional counter. An in situ laser alignment system allows precise location and rapid periodic alignment verification of the x-ray point source, the statically mounted Woelter optic, and the chosen detector.

  7. Highly Parallel, High-Precision Numerical Integration

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.

    2005-04-22

    This paper describes a scheme for rapidly computing numerical values of definite integrals to very high accuracy, ranging from ordinary machine precision to hundreds or thousands of digits, even for functions with singularities or infinite derivatives at endpoints. Such a scheme is of interest not only in computational physics and computational chemistry, but also in experimental mathematics, where high-precision numerical values of definite integrals can be used to numerically discover new identities. This paper discusses techniques for a parallel implementation of this scheme, then presents performance results for 1-D and 2-D test suites. Results are also given for a certain problem from mathematical physics, which features a difficult singularity, confirming a conjecture to 20,000 digit accuracy. The performance rate for this latter calculation on 1024 CPUs is 690 Gflop/s. We believe that this and one other 20,000-digit integral evaluation that we report are the highest-precision non-trivial numerical integrations performed to date.

  8. High precision laser photometer for laser optics

    NASA Astrophysics Data System (ADS)

    Zhao, Yuan'an; Hu, Guohang; Cao, Zhen; Liu, Shijie; Zhu, Meiping; Shao, Jianda

    2017-06-01

    Development of laser systems requires optical components with high performance, and a high-precision double-beam laser photometer was designed and established to measure the optical performance at 1064nm. Double beam design and lock-in technique was applied to decrease the impact of light energy instability and electric noise. Pairs of samples were placed symmetrically to eliminate beam displacement, and laser scattering imaging technique was applied to determine the influence of surface defect on the optical performance. Based on the above techniques, transmittance and reflection of pairs of optics were obtained, and the measurement precision was improved to 0.06%. Different types of optical loss, such as total loss, volume loss, residual reflection and surface scattering loss, were obtained from the transmittance and reflection measurement of samples with different thickness. Comparison of optical performance of the test points with and without surface defects, the influence of surface defects on optical performance was determined. The optical performance of Nd-glass at 1064nm were measured as an example. Different types of optical loss and the influence of surface defects on the optical loss was determined.

  9. High precision innovative micropump for artificial pancreas

    NASA Astrophysics Data System (ADS)

    Chappel, E.; Mefti, S.; Lettieri, G.-L.; Proennecke, S.; Conan, C.

    2014-03-01

    The concept of artificial pancreas, which comprises an insulin pump, a continuous glucose meter and a control algorithm, is a major step forward in managing patient with type 1 diabetes mellitus. The stability of the control algorithm is based on short-term precision micropump to deliver rapid-acting insulin and to specific integrated sensors able to monitor any failure leading to a loss of accuracy. Debiotech's MEMS micropump, based on the membrane pump principle, is made of a stack of 3 silicon wafers. The pumping chamber comprises a pillar check-valve at the inlet, a pumping membrane which is actuated against stop limiters by a piezo cantilever, an anti-free-flow outlet valve and a pressure sensor. The micropump inlet is tightly connected to the insulin reservoir while the outlet is in direct communication with the patient skin via a cannula. To meet the requirement of a pump dedicated to closed-loop application for diabetes care, in addition to the well-controlled displacement of the pumping membrane, the high precision of the micropump is based on specific actuation profiles that balance effect of pump elasticity in low-consumption push-pull mode.

  10. High Precision Rovibrational Spectroscopy of OH+

    NASA Astrophysics Data System (ADS)

    Markus, Charles R.; Hodges, James N.; Perry, Adam J.; Kocheril, G. Stephen; Müller, Holger S. P.; McCall, Benjamin J.

    2016-02-01

    The molecular ion OH+ has long been known to be an important component of the interstellar medium. Its relative abundance can be used to indirectly measure cosmic ray ionization rates of hydrogen, and it is the first intermediate in the interstellar formation of water. To date, only a limited number of pure rotational transitions have been observed in the laboratory making it necessary to indirectly calculate rotational levels from high-precision rovibrational spectroscopy. We have remeasured 30 transitions in the fundamental band with MHz-level precision, in order to enable the prediction of a THz spectrum of OH+. The ions were produced in a water cooled discharge of O2, H2, and He, and the rovibrational transitions were measured with the technique Noise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy. These values have been included in a global fit of field free data to a 3Σ- linear molecule effective Hamiltonian to determine improved spectroscopic parameters which were used to predict the pure rotational transition frequencies.

  11. High Precision Spectroscopy of Neutral Beryllium-9

    NASA Astrophysics Data System (ADS)

    Lau, Chui Yu; Williams, Will

    2015-05-01

    We report on the progress of high precision spectroscopy of the 2s2p singlet and triplet states in beryllium-9. Our goal is to improve the experimental precision on the energy levels of the 2s2p triplet J = 0, 1, and 2 states by a factor of 500, 100, and 500 respectively in order to delineate various theoretical predictions. The goal for the 2s2p singlet (J = 1) state is to improve the experimental precision on the energy level by a factor of 600 as a test of quantum electrodynamics. Our experimental setup consists of an oven capable of 1400 C that produces a collimated beam of neutral beryllium-9. The triplet states are probed with a 455 nm ECDL stabilized to a tellurium-210 line. The singlet state is probed with 235nm light from a frequency quadrupled titanium sapphire laser, where the frequency doubled light at 470 nm is stabilized to another tellurium-210 line. We also present our progress on improving the absolute accuracy of our frequency reference by using an ultrastable/low drift fiber coupled cavity.

  12. High-precision laser machining of ceramics

    NASA Astrophysics Data System (ADS)

    Toenshoff, Hans K.; von Alvensleben, Ferdinand; Graumann, Christoph; Willmann, Guido

    1998-09-01

    The increasing demand for highly developed ceramic materials for various applications calls for innovative machining technologies yielding high accuracy and efficiency. Associated problems with conventional, i.e. mechanical methods, are unacceptable tool wear as well as force induced damages on ceramic components. Furthermore, the established grinding techniques often meet their limits if accurate complex 2D or 3D structures are required. In contrast to insufficient mechanical processes, UV-laser precision machining of ceramics offers not only a valuable technological alternative but a considerable economical aspect as well. In particular, excimer lasers provide a multitude of advantages for applications in high precision and micro technology. Within the UV wavelength range and pulses emitted in the nano-second region, minimal thermal effects on ceramics and polymers are observed. Thus, the ablation geometry can be controlled precisely in the lateral and vertical directions. In this paper, the excimer laser machining technology developed at the Laser Zentrum Hannover is explained. Representing current and future industrial applications, examinations concerning the precision cutting of alumina (Al2O3), and HF-composite materials, the ablation of ferrite ceramics for precision inductors and the structuring of SiC sealing and bearing rings are presented.

  13. General-purpose event generators for LHC physics

    SciTech Connect

    Buckley, Andy; Butterworth, Jonathan; Gieseke, Stefan; Grellscheid, David; Hoche, Stefan; Hoeth, Hendrik; Krauss, Frank; Lonnblad, Leif; Nurse, Emily; Richardson, Peter; Schumann, Steffen; Seymour, Michael H.; Sjostrand, Torbjorn; Skands, Peter; Webber, Bryan; /Cambridge U.

    2011-03-03

    We review the physics basis, main features and use of general-purpose Monte Carlo event generators for the simulation of proton-proton collisions at the Large Hadron Collider. Topics included are: the generation of hard-scattering matrix elements for processes of interest, at both leading and next-to-leading QCD perturbative order; their matching to approximate treatments of higher orders based on the showering approximation; the parton and dipole shower formulations; parton distribution functions for event generators; non-perturbative aspects such as soft QCD collisions, the underlying event and diffractive processes; the string and cluster models for hadron formation; the treatment of hadron and tau decays; the inclusion of QED radiation and beyond-Standard-Model processes. We describe the principal features of the Ariadne, Herwig++, Pythia 8 and Sherpa generators, together with the Rivet and Professor validation and tuning tools, and discuss the physics philosophy behind the proper use of these generators and tools. This review is aimed at phenomenologists wishing to understand better how parton-level predictions are translated into hadron-level events as well as experimentalists wanting a deeper insight into the tools available for signal and background simulation at the LHC.

  14. Invasive genotypes are opportunistic specialists not general purpose genotypes

    PubMed Central

    Drown, Devin M; Levri, Edward P; Dybdahl, Mark F

    2011-01-01

    It is not clear which forms of plasticity in fitness-related traits are associated with invasive species. On one hand, it may be better to have a robust performance across environments. On the other, it may be beneficial to take advantage of limited favorable conditions. We chose to study a worldwide invasive species, Potamopyrgus antipodarum, and compare the plasticity of life-history traits of a sample of invasive genotypes to a sample of ancestral-range genotypes. We examined the responses to salinity in this freshwater snail because it varies spatially and temporally in the introduced range and contributes to variation in fitness in our system. We used a recently developed statistical method that quantifies aspects of differences in the shape among reaction norms. We found that the invasive lineages survived and reproduced with an increased probability at the higher salinities, and were superior to ancestral-range lineages in only two traits related to reproduction. Moreover, we found that in terms of traits related to growth, the invasive lineages have a performance optimum that is shifted to higher salinities than the ancestral-range lineages as well as having a narrower niche breadth. Contrary to the prediction of the general purpose genotype hypothesis, we found that invasive lineages tended to be opportunistic specialists. PMID:25567958

  15. ALEPH2 - A general purpose Monte Carlo depletion code

    SciTech Connect

    Stankovskiy, A.; Van Den Eynde, G.; Baeten, P.; Trakas, C.; Demy, P. M.; Villatte, L.

    2012-07-01

    The Monte-Carlo burn-up code ALEPH is being developed at SCK-CEN since 2004. A previous version of the code implemented the coupling between the Monte Carlo transport (any version of MCNP or MCNPX) and the ' deterministic' depletion code ORIGEN-2.2 but had important deficiencies in nuclear data treatment and limitations inherent to ORIGEN-2.2. A new version of the code, ALEPH2, has several unique features making it outstanding among other depletion codes. The most important feature is full data consistency between steady-state Monte Carlo and time-dependent depletion calculations. The last generation general-purpose nuclear data libraries (JEFF-3.1.1, ENDF/B-VII and JENDL-4) are fully implemented, including special purpose activation, spontaneous fission, fission product yield and radioactive decay data. The built-in depletion algorithm allows to eliminate the uncertainties associated with obtaining the time-dependent nuclide concentrations. A predictor-corrector mechanism, calculation of nuclear heating, calculation of decay heat, decay neutron sources are available as well. The validation of the code on the results of REBUS experimental program has been performed. The ALEPH2 has shown better agreement with measured data than other depletion codes. (authors)

  16. Programming methodology for a general purpose automation controller

    NASA Technical Reports Server (NTRS)

    Sturzenbecker, M. C.; Korein, J. U.; Taylor, R. H.

    1987-01-01

    The General Purpose Automation Controller is a multi-processor architecture for automation programming. A methodology has been developed whose aim is to simplify the task of programming distributed real-time systems for users in research or manufacturing. Programs are built by configuring function blocks (low-level computations) into processes using data flow principles. These processes are activated through the verb mechanism. Verbs are divided into two classes: those which support devices, such as robot joint servos, and those which perform actions on devices, such as motion control. This programming methodology was developed in order to achieve the following goals: (1) specifications for real-time programs which are to a high degree independent of hardware considerations such as processor, bus, and interconnect technology; (2) a component approach to software, so that software required to support new devices and technologies can be integrated by reconfiguring existing building blocks; (3) resistance to error and ease of debugging; and (4) a powerful command language interface.

  17. General purpose, field-portable cell-based biosensor platform.

    PubMed

    Gilchrist, K H; Barker, V N; Fletcher, L E; DeBusschere, B D; Ghanouni, P; Giovangrandi, L; Kovacs, G T

    2001-09-01

    There are several groups of researchers developing cell-based biosensors for chemical and biological warfare agents based on electrophysiologic monitoring of cells. In order to transition such sensors from the laboratory to the field, a general-purpose hardware and software platform is required. This paper describes the design, implementation, and field-testing of such a system, consisting of cell-transport and data acquisition instruments. The cell-transport module is a self-contained, battery-powered instrument that allows various types of cell-based modules to be maintained at a preset temperature and ambient CO(2) level while in transit or in the field. The data acquisition module provides 32 channels of action potential amplification, filtering, and real-time data streaming to a laptop computer. At present, detailed analysis of the data acquired is carried out off-line, but sufficient computing power is available in the data acquisition module to enable the most useful algorithms to eventually be run real-time in the field. Both modules have sufficient internal power to permit realistic field-testing, such as the example presented in this paper.

  18. General purpose free floating platform for KC-135 flight experimentation

    NASA Technical Reports Server (NTRS)

    Borchers, Bruce A.; Yendler, Boris S.; Kliss, Mark H.; Gonzales, Andrew A.; Edwards, Mark T.

    1994-01-01

    The Controlled Ecological Life Support Systems (CELSS) program is evaluating higher plants as a means of providing life support functions aboard space craft. These plant systems will be capable of regenerating air and water while meeting some of the food requirements of the crew. In order to grow plants in space, a series of systems are required to provide the necessary plant support functions. Some of the systems required for CELSS experiments are such that is is likely that existing technologies will require refinement, or novel technologies will need to be developed. To evaluate and test these technologies, a series of KC-135 precursor flights are being proposed. A general purpose free floating experiment platform is being developed to allow the KC-135 flights to be used to their fullest. This paper will outline the basic design for the CELSS Free Floating Test Bed (FFTB), and the requirements for the individual subsystems. Several preliminary experiments suitable for the free floater will also be discussed.

  19. High-Speed General Purpose Genetic Algorithm Processor.

    PubMed

    Hoseini Alinodehi, Seyed Pourya; Moshfe, Sajjad; Saber Zaeimian, Masoumeh; Khoei, Abdollah; Hadidi, Khairollah

    2016-07-01

    In this paper, an ultrafast steady-state genetic algorithm processor (GAP) is presented. Due to the heavy computational load of genetic algorithms (GAs), they usually take a long time to find optimum solutions. Hardware implementation is a significant approach to overcome the problem by speeding up the GAs procedure. Hence, we designed a digital CMOS implementation of GA in [Formula: see text] process. The proposed processor is not bounded to a specific application. Indeed, it is a general-purpose processor, which is capable of performing optimization in any possible application. Utilizing speed-boosting techniques, such as pipeline scheme, parallel coarse-grained processing, parallel fitness computation, parallel selection of parents, dual-population scheme, and support for pipelined fitness computation, the proposed processor significantly reduces the processing time. Furthermore, by relying on a built-in discard operator the proposed hardware may be used in constrained problems that are very common in control applications. In the proposed design, a large search space is achievable through the bit string length extension of individuals in the genetic population by connecting the 32-bit GAPs. In addition, the proposed processor supports parallel processing, in which the GAs procedure can be run on several connected processors simultaneously.

  20. General purpose free floating platform for KC-135 flight experimentation

    NASA Technical Reports Server (NTRS)

    Borchers, Bruce A.; Yendler, Boris S.; Kliss, Mark H.; Gonzales, Andrew A.; Edwards, Mark T.

    1994-01-01

    The Controlled Ecological Life Support Systems (CELSS) program is evaluating higher plants as a means of providing life support functions aboard space craft. These plant systems will be capable of regenerating air and water while meeting some of the food requirements of the crew. In order to grow plants in space, a series of systems are required to provide the necessary plant support functions. Some of the systems required for CELSS experiments are such that is is likely that existing technologies will require refinement, or novel technologies will need to be developed. To evaluate and test these technologies, a series of KC-135 precursor flights are being proposed. A general purpose free floating experiment platform is being developed to allow the KC-135 flights to be used to their fullest. This paper will outline the basic design for the CELSS Free Floating Test Bed (FFTB), and the requirements for the individual subsystems. Several preliminary experiments suitable for the free floater will also be discussed.

  1. Nondestructive inspection of General Purpose Heat Source (GPHS) girth welds

    SciTech Connect

    Reimus, M.A.H.; George, T.G.; Lynch, C.

    1998-12-31

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements. The GPHS is fabricated using iridium capsules, TIG welded, to contain the {sup 238}PuO{sub 2} fuel pellet. GPHS capsules will be utilized in the upcoming Cassini mission to explore Saturn and its moons. The physical integrity of the girth weld is important to mission safety and performance. Since experience in the past had revealed a potential for initiation of small cracks in the girth weld overlap zone, a nondestructive inspection of the capsule weld is required. A ultrasonic method was used to inspect the welds of capsules fabricated for the Galileo mission. The instrument, transducer, and method used were state of the art at the time (early 1980s). The ultrasonic instrumentation and methods used to inspect the Cassini GPHSs was significantly upgraded from those used for the Galileo mission. GPHSs that had ultrasonic reflectors that exceeded the reject specification level were subsequently inspected with radiography to provide additional engineering data used to accept/reject the heat source. This paper describes the Galileo-era ultrasonic instrumentation and methods and the subsequent upgrades made to support testing of Cassini GPHSs. Also discussed is the data obtained from radiographic examination and correlation to ultrasonic examination results.

  2. The General Purpose Work Station, a spacious microgravity workbench

    NASA Technical Reports Server (NTRS)

    Dalton, Bonnie P.; Schmidt, Greg K.; Savage, P. D.

    1992-01-01

    The General Purpose Work Station (GPWS) is a laboratory multiuse facility, as demonstrated during the Spacelab Life Sciences 1 (SLS-1) flight. The unit provided particulate containment under varying conditions, served as an effective work space for manipulating live animals, e.g., rats, served as a containment facility for fixatives, and was proposed for use to conduct in-flight maintenance during connector pin repair. The cabinet has a front door large enough to allow installation of a full-size microscope in-flight and is outfitted with a side window to allow delivery of items into the cabinet without exposure to the spacelab atmosphere. Additional support subsystems include inside cabinet mounting, surgical glove fine manipulations capability, and ac or dc power supply for experiment equipment, as will be demonstrated during Spacelab J. The GPWS, integrated and maintained in a double flight-rack, interfaces to spacelab systems including water cooling, avionics and cabin air, and power. Verification has been completed for multiple spacelab scenarios including SLS-2, SL-J, and SLS-3.

  3. High Precision Isotopic Reference Material Program

    NASA Astrophysics Data System (ADS)

    Mann, J. L.; Vocke, R. D.

    2007-12-01

    Recent developments in thermal ionization and inductively coupled plasma multicollector mass spectrometers have lead to "high precision" isotope ratio measurements with uncertainties approaching a few parts in 106. These new measurement capabilities have revolutionized the study of isotopic variations in nature by increasing the number of elements showing natural variations by almost a factor of two, and new research areas are actively opening up in climate change, health, ecology, geology and forensic studies. Because the isotopic applications are impacting very diverse fields, there is at present little effective coordination between research laboratories over reference materials and the values to apply to those materials. NIST had originally developed the techniques for producing accurate isotopic characterizations, culminating in the NIST Isotopic SRM series. The values on existing materials however are insufficiently precise and, in some cases, may be isotopically heterogeneous. A new generation of isotopic standards is urgently needed and will directly affect the quality and scope of emergent applications and ensure that the results being derived from these diverse fields are comparable. A series of new isotopic reference materials similar to the NIST 3100 single element solution series is being designed for this purpose and twelve elements have been selected as having the most pressing need. In conjunction with other expert users and National Metrology Institutes, an isotopic characterization of the respective 12 selected ampoules from the NIST single element solution series is currently underway. In this presentation the preliminary results of this screening will be discussed as well as the suitability of these materials in terms of homogeneity and purity, long term stability and availability, and isotopic relevance. Approaches to value assignment will also be discussed.

  4. High precision optical surface metrology using deflectometry

    NASA Astrophysics Data System (ADS)

    Huang, Run

    Software Configurable Optical Test System (SCOTS) developed at University of Arizona is a highly efficient optical metrology technique based on the principle of deflectometry, which can achieve comparable accuracy with interferometry but with low-cost hardware. In a SCOTS test, an LCD display is used to generate structured light pattern to illuminate the test optics and the reflected light is captured by a digital camera. The surface slope of test optics is determined by triangulation of the display pixels, test optics, and the camera. The surface shape is obtained by the integration of the slopes. Comparing to interferometry, which has long served as an accurate non-contact optical metrology technology, SCOTS overcomes the limitation of dynamic range and sensitivity to environment. It is able to achieve high dynamic range slope measurement without requiring null optics. In this dissertation, the sensitivity and performance of the test system have been analyzed comprehensively. Sophisticated calibrations of system components have been investigated and implemented in different metrology projects to push this technology to a higher accuracy including low-order terms. A compact on-axis SCOTS system lowered the testing geometry sensitivity in the metrology of 1-meter highly aspheric secondary mirror of Large Binocular Telescope. Sub-nm accuracy was achieved in testing a high precision elliptical X-ray mirror by using reference calibration. A well-calibrated SCOTS was successfully constructed and is, at the time of writing this dissertation, being used to provide surface metrology feedback for the fabrication of the primary mirror of Daniel K. Inouye Solar Telescope which is a 4-meter off-axis parabola with more than 8 mm aspherical departure.

  5. Fiber Scrambling for High Precision Spectrographs

    NASA Astrophysics Data System (ADS)

    Kaplan, Zachary; Spronck, J. F. P.; Fischer, D.

    2011-05-01

    The detection of Earth-like exoplanets with the radial velocity method requires extreme Doppler precision and long-term stability in order to measure tiny reflex velocities in the host star. Recent planet searches have led to the detection of so called "super-Earths” (up to a few Earth masses) that induce radial velocity changes of about 1 m/s. However, the detection of true Earth analogs requires a precision of 10 cm/s. One of the largest factors limiting Doppler precision is variation in the Point Spread Function (PSF) from observation to observation due to changes in the illumination of the slit and spectrograph optics. Thus, this stability has become a focus of current instrumentation work. Fiber optics have been used since the 1980's to couple telescopes to high-precision spectrographs, initially for simpler mechanical design and control. However, fiber optics are also naturally efficient scramblers. Scrambling refers to a fiber's ability to produce an output beam independent of input. Our research is focused on characterizing the scrambling properties of several types of fibers, including circular, square and octagonal fibers. By measuring the intensity distribution after the fiber as a function of input beam position, we can simulate guiding errors that occur at an observatory. Through this, we can determine which fibers produce the most uniform outputs for the severest guiding errors, improving the PSF and allowing sub-m/s precision. However, extensive testing of fibers of supposedly identical core diameter, length and shape from the same manufacturer has revealed the "personality” of individual fibers. Personality describes differing intensity patterns for supposedly duplicate fibers illuminated identically. Here, we present our results on scrambling characterization as a function of fiber type, while studying individual fiber personality.

  6. SNAP: A General Purpose Network Analysis and Graph Mining Library

    PubMed Central

    Leskovec, Jure; Sosič, Rok

    2016-01-01

    Large networks are becoming a widely used abstraction for studying complex systems in a broad set of disciplines, ranging from social network analysis to molecular biology and neuroscience. Despite an increasing need to analyze and manipulate large networks, only a limited number of tools are available for this task. Here, we describe Stanford Network Analysis Platform (SNAP), a general-purpose, high-performance system that provides easy to use, high-level operations for analysis and manipulation of large networks. We present SNAP functionality, describe its implementational details, and give performance benchmarks. SNAP has been developed for single big-memory machines and it balances the trade-off between maximum performance, compact in-memory graph representation, and the ability to handle dynamic graphs where nodes and edges are being added or removed over time. SNAP can process massive networks with hundreds of millions of nodes and billions of edges. SNAP offers over 140 different graph algorithms that can efficiently manipulate large graphs, calculate structural properties, generate regular and random graphs, and handle attributes and meta-data on nodes and edges. Besides being able to handle large graphs, an additional strength of SNAP is that networks and their attributes are fully dynamic, they can be modified during the computation at low cost. SNAP is provided as an open source library in C++ as well as a module in Python. We also describe the Stanford Large Network Dataset, a set of social and information real-world networks and datasets, which we make publicly available. The collection is a complementary resource to our SNAP software and is widely used for development and benchmarking of graph analytics algorithms. PMID:28344853

  7. Use of general purpose graphics processing units with MODFLOW.

    PubMed

    Hughes, Joseph D; White, Jeremy T

    2013-01-01

    To evaluate the use of general-purpose graphics processing units (GPGPUs) to improve the performance of MODFLOW, an unstructured preconditioned conjugate gradient (UPCG) solver has been developed. The UPCG solver uses a compressed sparse row storage scheme and includes Jacobi, zero fill-in incomplete, and modified-incomplete lower-upper (LU) factorization, and generalized least-squares polynomial preconditioners. The UPCG solver also includes options for sequential and parallel solution on the central processing unit (CPU) using OpenMP. For simulations utilizing the GPGPU, all basic linear algebra operations are performed on the GPGPU; memory copies between the central processing unit CPU and GPCPU occur prior to the first iteration of the UPCG solver and after satisfying head and flow criteria or exceeding a maximum number of iterations. The efficiency of the UPCG solver for GPGPU and CPU solutions is benchmarked using simulations of a synthetic, heterogeneous unconfined aquifer with tens of thousands to millions of active grid cells. Testing indicates GPGPU speedups on the order of 2 to 8, relative to the standard MODFLOW preconditioned conjugate gradient (PCG) solver, can be achieved when (1) memory copies between the CPU and GPGPU are optimized, (2) the percentage of time performing memory copies between the CPU and GPGPU is small relative to the calculation time, (3) high-performance GPGPU cards are utilized, and (4) CPU-GPGPU combinations are used to execute sequential operations that are difficult to parallelize. Furthermore, UPCG solver testing indicates GPGPU speedups exceed parallel CPU speedups achieved using OpenMP on multicore CPUs for preconditioners that can be easily parallelized. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  8. Use of general purpose graphics processing units with MODFLOW

    USGS Publications Warehouse

    Hughes, Joseph D.; White, Jeremy T.

    2013-01-01

    To evaluate the use of general-purpose graphics processing units (GPGPUs) to improve the performance of MODFLOW, an unstructured preconditioned conjugate gradient (UPCG) solver has been developed. The UPCG solver uses a compressed sparse row storage scheme and includes Jacobi, zero fill-in incomplete, and modified-incomplete lower-upper (LU) factorization, and generalized least-squares polynomial preconditioners. The UPCG solver also includes options for sequential and parallel solution on the central processing unit (CPU) using OpenMP. For simulations utilizing the GPGPU, all basic linear algebra operations are performed on the GPGPU; memory copies between the central processing unit CPU and GPCPU occur prior to the first iteration of the UPCG solver and after satisfying head and flow criteria or exceeding a maximum number of iterations. The efficiency of the UPCG solver for GPGPU and CPU solutions is benchmarked using simulations of a synthetic, heterogeneous unconfined aquifer with tens of thousands to millions of active grid cells. Testing indicates GPGPU speedups on the order of 2 to 8, relative to the standard MODFLOW preconditioned conjugate gradient (PCG) solver, can be achieved when (1) memory copies between the CPU and GPGPU are optimized, (2) the percentage of time performing memory copies between the CPU and GPGPU is small relative to the calculation time, (3) high-performance GPGPU cards are utilized, and (4) CPU-GPGPU combinations are used to execute sequential operations that are difficult to parallelize. Furthermore, UPCG solver testing indicates GPGPU speedups exceed parallel CPU speedups achieved using OpenMP on multicore CPUs for preconditioners that can be easily parallelized.

  9. SNAP: A General Purpose Network Analysis and Graph Mining Library.

    PubMed

    Leskovec, Jure; Sosič, Rok

    2016-10-01

    Large networks are becoming a widely used abstraction for studying complex systems in a broad set of disciplines, ranging from social network analysis to molecular biology and neuroscience. Despite an increasing need to analyze and manipulate large networks, only a limited number of tools are available for this task. Here, we describe Stanford Network Analysis Platform (SNAP), a general-purpose, high-performance system that provides easy to use, high-level operations for analysis and manipulation of large networks. We present SNAP functionality, describe its implementational details, and give performance benchmarks. SNAP has been developed for single big-memory machines and it balances the trade-off between maximum performance, compact in-memory graph representation, and the ability to handle dynamic graphs where nodes and edges are being added or removed over time. SNAP can process massive networks with hundreds of millions of nodes and billions of edges. SNAP offers over 140 different graph algorithms that can efficiently manipulate large graphs, calculate structural properties, generate regular and random graphs, and handle attributes and meta-data on nodes and edges. Besides being able to handle large graphs, an additional strength of SNAP is that networks and their attributes are fully dynamic, they can be modified during the computation at low cost. SNAP is provided as an open source library in C++ as well as a module in Python. We also describe the Stanford Large Network Dataset, a set of social and information real-world networks and datasets, which we make publicly available. The collection is a complementary resource to our SNAP software and is widely used for development and benchmarking of graph analytics algorithms.

  10. High-precision ground-based photometry of exoplanets

    NASA Astrophysics Data System (ADS)

    de Mooij, Ernst J. W.; Jayawardhana, Ray

    2013-04-01

    High-precision photometry of transiting exoplanet systems has contributed significantly to our understanding of the properties of their atmospheres. The best targets are the bright exoplanet systems, for which the high number of photons allow very high signal-to-noise ratios. Most of the current instruments are not optimised for these high-precision measurements, either they have a large read-out overhead to reduce the readnoise and/or their field-of-view is limited, preventing simultaneous observations of both the target and a reference star. Recently we have proposed a new wide-field imager for the Observatoir de Mont-Megantic optimised for these bright systems (PI: Jayawardhana). The instruments has a dual beam design and a field-of-view of 17' by 17'. The cameras have a read-out time of 2 seconds, significantly reducing read-out overheads. Over the past years we have obtained significant experience with how to reach the high precision required for the characterisation of exoplanet atmospheres. Based on our experience we provide the following advice: Get the best calibrations possible. In the case of bad weather, characterise the instrument (e.g. non-linearity, dome flats, bias level), this is vital for better understanding of the science data. Observe the target for as long as possible, the out-of-transit baseline is as important as the transit/eclipse itself. A short baseline can lead to improperly corrected systematic and mis-estimation of the red-noise. Keep everything (e.g. position on detector, exposure time) as stable as possible. Take care that the defocus is not too strong. For a large defocus, the contribution of the total flux from the sky-background in the aperture could well exceed that of the target, resulting in very strict requirements on the precision at which the background is measured.

  11. Polymeric MST - high precision at low cost

    NASA Astrophysics Data System (ADS)

    Elderstig, Håkan; Larsson, Olle

    1997-09-01

    A low-cost production process for fabrication of polymeric microstructures from micromachined silicon is demonstrated in a splice for the splicing of optical fibers and an optical motherboard. Measurements on splices showed less than 0.5 dB insertion losses. The prototype polymeric motherboard concisted of an optical receiver module. The detector that was mounted on the polymeric optical motherboard detected about 70% of the transferred light. Measurements with modulated light indicates an optical bandwidth of 5 GHz at 2 V reverse current on the pin-diode.

  12. General-Purpose Driver For Arrays Of Photodetectors

    NASA Technical Reports Server (NTRS)

    Shu, Peter K.; Travis, Jeffrey W.; Lee, John T. S.

    1993-01-01

    Electronic system containing both digital and analog circuits supplies clock waveforms at frequencies up to 12 MHz and/or bias voltages in 16 output channels. Designed to provide low-noise driving signals for any of variety of arrays of photodetectors. Clock waveform and/or bias in each channel adjusted independently of others to suit requirements of specific array of detectors. System offers primary advantage (adjustability) of prior laboratory systems, but at cost, power, and size like those of prior dedicated, field-deployed systems.

  13. CHEOPS: a space telescope for ultra-high precision photometry of exoplanet transits

    NASA Astrophysics Data System (ADS)

    Fortier, Andrea; Beck, Thomas; Benz, Willy; Broeg, Christopher; Cessa, Virginie; Ehrenreich, David; Thomas, Nicolas

    2014-08-01

    The CHaracterising ExOPlanet Satellite (CHEOPS) is a joint ESA-Switzerland space mission (expected to launch in 2017) dedicated to search for exoplanet transits by means of ultra-high precision photometry. CHEOPS will provide accurate radii for planets down to Earth size. Targets will mainly come from radial velocity surveys. The CHEOPS instrument is an optical space telescope of 30 cm clear aperture with a single focal plane CCD detector. The tube assembly is passively cooled and thermally controlled to support high precision, low noise photometry. The telescope feeds a re-imaging optic, which supports the straylight suppression concept to achieve the required Signal to Noise.

  14. Aerodynamic window for high precision laser drilling

    NASA Astrophysics Data System (ADS)

    Sommer, Steffen; Dausinger, Friedrich; Berger, Peter; Hügel, Helmuth

    2007-05-01

    High precision laser drilling is getting more and more interesting for industry. Main applications for such holes are vaporising and injection nozzles. To enhance quality, the energy deposition has to be accurately defined by reducing the pulse duration and thereby reducing the amount of disturbing melting layer. In addition, an appropriate processing technology, for example the helical drilling, yields holes in steel at 1 mm thickness and diameters about 100 μm with correct roundness and thin recast layers. However, the processing times are still not short enough for industrial use. Experiments have shown that the reduction of the atmospheric pressure down to 100 hPa enhances the achievable quality and efficiency, but the use of vacuum chambers in industrial processes is normally quite slow and thus expensive. The possibility of a very fast evacuation is given by the use of an aerodynamic window, which produces the pressure reduction by virtue of its fluid dynamic features. This element, based on a potential vortex, was developed and patented as out-coupling window for high power CO II lasers by IFSW 1, 2, 3. It has excellent tightness and transmission properties, and a beam deflection is not detectable. The working medium is compressed air, only. For the use as vacuum element for laser drilling, several geometrical modifications had to be realized. The prototype is small enough to be integrated in a micromachining station and has a low gas flow. During the laser pulse, which is focussed through the potential flow, a very high fluence is reached, but the measurements have not shown any beam deflection or focal shifting. The evacuation time is below 300 ms so that material treatment with changing ambient pressure is possible, too. Experimental results have proven the positive effect of the reduced ambient pressure on the drilling process for the regime of nano- and picosecond laser pulses. Plasma effects are reduced and, because of the less absorption, the

  15. CLOUDCLOUD : general-purpose instrument monitoring and data managing software

    NASA Astrophysics Data System (ADS)

    Dias, António; Amorim, António; Tomé, António

    2016-04-01

    An effective experiment is dependent on the ability to store and deliver data and information to all participant parties regardless of their degree of involvement in the specific parts that make the experiment a whole. Having fast, efficient and ubiquitous access to data will increase visibility and discussion, such that the outcome will have already been reviewed several times, strengthening the conclusions. The CLOUD project aims at providing users with a general purpose data acquisition, management and instrument monitoring platform that is fast, easy to use, lightweight and accessible to all participants of an experiment. This work is now implemented in the CLOUD experiment at CERN and will be fully integrated with the experiment as of 2016. Despite being used in an experiment of the scale of CLOUD, this software can also be used in any size of experiment or monitoring station, from single computers to large networks of computers to monitor any sort of instrument output without influencing the individual instrument's DAQ. Instrument data and meta data is stored and accessed via a specially designed database architecture and any type of instrument output is accepted using our continuously growing parsing application. Multiple databases can be used to separate different data taking periods or a single database can be used if for instance an experiment is continuous. A simple web-based application gives the user total control over the monitored instruments and their data, allowing data visualization and download, upload of processed data and the ability to edit existing instruments or add new instruments to the experiment. When in a network, new computers are immediately recognized and added to the system and are able to monitor instruments connected to them. Automatic computer integration is achieved by a locally running python-based parsing agent that communicates with a main server application guaranteeing that all instruments assigned to that computer are

  16. A damage mechanics based general purpose interface/contact element

    NASA Astrophysics Data System (ADS)

    Yan, Chengyong

    laboratory test data presented in the literature. The results demonstrate that the proposed element and the damage law perform very well. The most important scientific contribution of this dissertation is the proposed damage criterion based on second law of thermodynamic and entropy of the system. The proposed general purpose interface/contact element is another contribution of this research. Compared to the previous adhoc interface elements proposed in the literature, the new one is, much more powerful and includes creep, plastic deformations, sliding, temperature, damage, cyclic behavior and fatigue life in a unified formulation.

  17. High Precision Sunphotometer using Wide Dynamic Range (WDR) Camera Tracking

    NASA Astrophysics Data System (ADS)

    Liss, J.; Dunagan, S. E.; Johnson, R. R.; Chang, C. S.; LeBlanc, S. E.; Shinozuka, Y.; Redemann, J.; Flynn, C. J.; Segal-Rosenhaimer, M.; Pistone, K.; Kacenelenbogen, M. S.; Fahey, L.

    2016-12-01

    High Precision Sunphotometer using Wide Dynamic Range (WDR) Camera TrackingThe NASA Ames Sun-photometer-Satellite Group, DOE, PNNL Atmospheric Sciences and Global Change Division, and NASA Goddard's AERONET (AErosol RObotic NETwork) team recently collaborated on the development of a new airborne sunphotometry instrument that provides information on gases and aerosols extending far beyond what can be derived from discrete-channel direct-beam measurements, while preserving or enhancing many of the desirable AATS features (e.g., compactness, versatility, automation, reliability). The enhanced instrument combines the sun-tracking ability of the current 14-Channel NASA Ames AATS-14 with the sky-scanning ability of the ground-based AERONET Sun/sky photometers, while extending both AATS-14 and AERONET capabilities by providing full spectral information from the UV (350 nm) to the SWIR (1,700 nm). Strengths of this measurement approach include many more wavelengths (isolated from gas absorption features) that may be used to characterize aerosols and detailed (oversampled) measurements of the absorption features of specific gas constituents. The Sky Scanning Sun Tracking Airborne Radiometer (3STAR) replicates the radiometer functionality of the AATS-14 instrument but incorporates modern COTS technologies for all instruments subsystems. A 19-channel radiometer bundle design is borrowed from a commercial water column radiance instrument manufactured by Biospherical Instruments of San Diego California (ref, Morrow and Hooker)) and developed using NASA funds under the Small Business Innovative Research (SBIR) program. The 3STAR design also incorporates the latest in robotic motor technology embodied in Rotary actuators from Oriental motor Corp. having better than 15 arc seconds of positioning accuracy. Control system was designed, tested and simulated using a Hybrid-Dynamical modeling methodology. The design also replaces the classic quadrant detector tracking sensor with a

  18. Tests of a Fast Plastic Scintillator for High-Precision Half-Life Measurements

    NASA Astrophysics Data System (ADS)

    Laffoley, A. T.; Dunlop, R.; Finlay, P.; Leach, K. G.; Michetti-Wilson, J.; Rand, E. T.; Svensson, C. E.; Grinyer, G. F.; Thomas, J. C.; Ball, G.; Garnsworthy, A. B.; Hackman, G.; Orce, J. N.; Triambak, S.; Williams, S. J.; Andreoiu, C.; Cross, D.

    2013-03-01

    A fast plastic scintillator detector is evaluated for possible use in an ongoing program of high-precision half-life measurements of short lived β emitters. Using data taken at TRI-UMF's Isotope Separator and Accelerator Facility with a radioactive 26Na beam, a detailed investigation of potential systematic effects with this new detector setup is being performed. The technique will then be applied to other β-decay half-life measurements including the superallowed Fermi β emitters 10C, 14O, and T = 1/2 decay of 15O.

  19. HIGH-PRECISION ASTROMETRY WITH A DIFFRACTIVE PUPIL TELESCOPE

    SciTech Connect

    Guyon, Olivier; Eisner, Josh A.; Angel, Roger; Woolf, Neville J.; Bendek, Eduardo A.; Milster, Thomas D.; Mark Ammons, S.; Shao, Michael; Shaklan, Stuart; Levine, Marie; Nemati, Bijan; Pitman, Joe; Woodruff, Robert A.; Belikov, Ruslan

    2012-06-01

    Astrometric detection and mass determination of Earth-mass exoplanets require sub-{mu}as accuracy, which is theoretically possible with an imaging space telescope using field stars as an astrometric reference. The measurement must, however, overcome astrometric distortions, which are much larger than the photon noise limit. To address this issue, we propose to generate faint stellar diffraction spikes using a two-dimensional grid of regularly spaced small dark spots added to the surface of the primary mirror (PM). Accurate astrometric motion of the host star is obtained by comparing the position of the spikes to the background field stars. The spikes do not contribute to scattered light in the central part of the field and therefore allow unperturbed coronagraphic observation of the star's immediate surroundings. Because the diffraction spikes are created on the PM and imaged on the same focal plane detector as the background stars, astrometric distortions affect equally the diffraction spikes and the background stars and are therefore calibrated. We describe the technique, detail how the data collected by the wide-field camera are used to derive astrometric motion, and identify the main sources of astrometric error using numerical simulations and analytical derivations. We find that the 1.4 m diameter telescope, 0.3 deg{sup 2} field we adopt as a baseline design achieves 0.2 {mu}as single measurement astrometric accuracy. The diffractive pupil concept thus enables sub-{mu}as astrometry without relying on the accurate pointing, external metrology, or high-stability hardware required with previously proposed high-precision astrometry concepts.

  20. Detectors

    DOEpatents

    Orr, Christopher Henry; Luff, Craig Janson; Dockray, Thomas; Macarthur, Duncan Whittemore; Bounds, John Alan; Allander, Krag

    2002-01-01

    The apparatus and method provide techniques through which both alpha and beta emission determinations can be made simultaneously using a simple detector structure. The technique uses a beta detector covered in an electrically conducting material, the electrically conducting material discharging ions generated by alpha emissions, and as a consequence providing a measure of those alpha emissions. The technique also offers improved mountings for alpha detectors and other forms of detectors against vibration and the consequential effects vibration has on measurement accuracy.

  1. Optimization of a general-purpose, actively scanned proton beamline for ocular treatments: Geant4 simulations.

    PubMed

    Piersimoni, Pierluigi; Rimoldi, Adele; Riccardi, Cristina; Pirola, Michele; Molinelli, Silvia; Ciocca, Mario

    2015-03-08

    The Italian National Center for Hadrontherapy (CNAO, Centro Nazionale di Adroterapia Oncologica), a synchrotron-based hospital facility, started the treatment of patients within selected clinical trials in late 2011 and 2012 with actively scanned proton and carbon ion beams, respectively. The activation of a new clinical protocol for the irradiation of uveal melanoma using the existing general-purpose proton beamline is foreseen for late 2014. Beam characteristics and patient treatment setup need to be tuned to meet the specific requirements for such a type of treatment technique. The aim of this study is to optimize the CNAO transport beamline by adding passive components and minimizing air gap to achieve the optimal conditions for ocular tumor irradiation. The CNAO setup with the active and passive components along the transport beamline, as well as a human eye-modeled detector also including a realistic target volume, were simulated using the Monte Carlo Geant4 toolkit. The strong reduction of the air gap between the nozzle and patient skin, as well as the insertion of a range shifter plus a patient-specific brass collimator at a short distance from the eye, were found to be effective tools to be implemented. In perspective, this simulation toolkit could also be used as a benchmark for future developments and testing purposes on commercial treatment planning systems.

  2. Cross-Cultural Competency in the General Purpose Force: Training Strategies and Implications for Future Operations

    DTIC Science & Technology

    2013-04-09

    SUBTITLE Cross-Cultural Competency in the General Purpose Force: Training Strategies and Implications for Future Operations 5a. CONTRACT NUMBER N/A...NOTES N/A 14. ABSTRACT An abundance of research in Cross-Cultural Competency (C3) is conclusive in recognizing the value it has for General Purpose...might currently be in jeopardy. 15. SUBJECT TERMS Culture, Cross Cultural Competency , Cultural Agility, General Purpose Forces, Marine Corps Center

  3. The Use of General Purpose Computer Programs to Derive Equations of Motion for Optimal Isolation Studies

    NASA Technical Reports Server (NTRS)

    Pilkey, W. D.; Chen, Y. H.

    1975-01-01

    Techniques were developed that utilize general purpose structural analysis computer programs to generate the equations of motion necessary for limiting performance studies. The methodology necessary to couple available general purpose finite element structural programs to a limiting performance capability was developed. Primary emphasis was given to the use of the general purpose program to develop equations of motion in a form that can be used by the limiting performance program.

  4. 78 FR 77662 - Notice of Availability (NOA) for General Purpose Warehouse and Information Technology Center...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-24

    ... Technology Center Construction (GPW/IT)--Tracy Site-- Environmental Assessment (EA); Finding of No... General Purpose Warehouse and Information Technology Center Construction (GPW/IT)--Tracy Site... the General Purpose Warehouse and Information Technology Center Construction (GPW/IT)--Tracy Site--EA...

  5. Application of a Computerized General Purpose Information Management System (SELGEM) to Medically Important Arthropods (Diptera: Culcidae).

    DTIC Science & Technology

    1980-06-01

    COMPUTERIZED GENERAL PURPOSE INFORMATION MANAGEMENT SYSTEM (SELGE.M) TO KEDICALLY IMPORTANT ARTHROPODS (DIPTERA: CULICIDAE) Annual Report Terry L. Erwin June...GENERAL PURPOSE INFORMATION MANAGEMENT SYSTEM Annual--1 September 1979- (SEIGEM) TO MEDICALLY ThWORTANT ARTHROPODS 30 May 1980 (DIPTERA: CULICIDAE) 6

  6. High precision spectroscopy and imaging in THz frequency range

    NASA Astrophysics Data System (ADS)

    Vaks, Vladimir L.

    2014-03-01

    Application of microwave methods for development of the THz frequency range has resulted in elaboration of high precision THz spectrometers based on nonstationary effects. The spectrometers characteristics (spectral resolution and sensitivity) meet the requirements for high precision analysis. The gas analyzers, based on the high precision spectrometers, have been successfully applied for analytical investigations of gas impurities in high pure substances. These investigations can be carried out both in absorption cell and in reactor. The devices can be used for ecological monitoring, detecting the components of chemical weapons and explosive in the atmosphere. The great field of THz investigations is the medicine application. Using the THz spectrometers developed one can detect markers for some diseases in exhaled air.

  7. High precision, low disturbance calibration system for the CMS Barrel Electromagnetic Calorimeter High Voltage apparatus

    NASA Astrophysics Data System (ADS)

    Fasanella, G.

    2017-01-01

    The CMS Electromagnetic Calorimeter utilizes scintillation lead tungstate crystals, with avalanche photodiodes (APD) as photo-detectors in the barrel part. 1224 HV channels bias groups of 50 APD pairs, each at a voltage of about 380 V. The APD gain dependence on the voltage is 3%/V. A stability of better than 60 mV is needed to have negligible impact on the calorimeter energy resolution. Until 2015 manual calibrations were performed yearly. A new calibration system was deployed recently, which satisfies the requirement of low disturbance and high precision. The system is discussed in detail and first operational experience is presented.

  8. A high precision gamma-ray spectrometer for the Mars-94 mission

    SciTech Connect

    Mitrofanov, I.G.; Anfimov, D.S.; Chernenko, A.M.

    1994-06-01

    The high precision gamma-ray spectrometer (PGS) is scheduled to be launched on the Mars-94 mission in October 1994, and to go into an elliptical polar orbit around Mars. The PGS consists of two high-purity germanium (Ge) detectors, associated electronics, and a passive cooler and will be mounted on one of the solar panels. The PGS will measure nuclear gamma-ray emissions from the martian surface, cosmic gamma-ray bursts, and the high-energy component of solar flares in the broad energy range from 50 KeV to 8 MeV using 4096 energy channels.

  9. In vivo dosimetry in intraoperative electron radiotherapy: microMOSFETs, radiochromic films and a general-purpose linac.

    PubMed

    López-Tarjuelo, Juan; Bouché-Babiloni, Ana; Morillo-Macías, Virginia; de Marco-Blancas, Noelia; Santos-Serra, Agustín; Quirós-Higueras, Juan David; Ferrer-Albiach, Carlos

    2014-10-01

    In vivo dosimetry is desirable for the verification, recording, and eventual correction of treatment in intraoperative electron radiotherapy (IOERT). Our aim is to share our experience of metal oxide semiconductor field-effect transistors (MOSFETs) and radiochromic films with patients undergoing IOERT using a general-purpose linac. We used MOSFETs inserted into sterile bronchus catheters and radiochromic films that were cut, digitized, and sterilized by means of gas plasma. In all, 59 measurements were taken from 27 patients involving 15 primary tumors (seven breast and eight non-breast tumors) and 12 relapses. Data were subjected to an outliers' analysis and classified according to their compatibility with the relevant doses. Associations were sought regarding the type of detector, breast and non-breast irradiation, and the radiation oncologist's assessment of the difficulty of detector placement. At the same time, 19 measurements were carried out at the tumor bed with both detectors. MOSFET measurements ([Formula: see text]  = 93.5 %, sD  =  6.5 %) were not significantly shifted from film measurements ([Formula: see text]  =  96.0 %, sD  =  5.5 %; p  =  0.109), and no associations were found (p = 0.526, p = 0.295,  and p = 0.501, respectively). As regards measurements performed at the tumor bed with both detectors, MOSFET measurements ([Formula: see text]  =  95.0 %, sD  =  5.4 % were not significantly shifted from film measurements ([Formula: see text]  =  96.4 %, sD  =  5.0 %; p  =  0.363). In vivo dosimetry can produce satisfactory results at every studied location with a general-purpose linac. Detector choice should depend on user factors, not on the detector performance itself. Surgical team collaboration is crucial to success.

  10. VIEW OF MICROMACHINING, HIGH PRECISION EQUIPMENT USED TO CUSTOM MAKE ...

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

    VIEW OF MICRO-MACHINING, HIGH PRECISION EQUIPMENT USED TO CUSTOM MAKE SMALL PARTS. LUMPS OF CLAY; SHOWN IN THE PHOTOGRAPH, WERE USED TO STABILIZE PARTS BEING MACHINED. (11/1/87) - Rocky Flats Plant, Stainless Steel & Non-Nuclear Components Manufacturing, Southeast corner of intersection of Cottonwood & Third Avenues, Golden, Jefferson County, CO

  11. General purpose nonlinear system solver based on Newton-Krylov method.

    SciTech Connect

    2013-12-01

    KINSOL is part of a software family called SUNDIALS: SUite of Nonlinear and Differential/Algebraic equation Solvers [1]. KINSOL is a general-purpose nonlinear system solver based on Newton-Krylov and fixed-point solver technologies [2].

  12. The high precision measurement of the 144Ce activity in the SOX experiment

    NASA Astrophysics Data System (ADS)

    Di Noto, L.; Agostini, M.; Althenmüller, K.; Appel, S.; Bellini, G.; Benziger, J.; Berton, N.; Bick, D.; Bonfini, G.; Bravo—Berguño, D.; Caccianiga, B.; Calaprice, F.; Caminata, A.; Cavalcante, P.; Cereseto, R.; Chepurnov, A.; Choi, K.; Cribier, M.; DAngelo, D.; Davini, S.; Derbin, A.; Drachnev, I.; Durero, M.; Etenko, A.; Farinon, S.; Fischer, V.; Fomenko, K.; Franco, D.; Gabriele, F.; Gaffiot, J.; Galbiati, C.; Ghiano, C.; Giammarchi, M.; Göeger-Neff, M.; Goretti, A.; Gromov, M.; Hagner, C.; Houdy, Th; Hungerford, E.; Ianni, Aldo; Ianni, Andrea; Jonquères, N.; Jedrzejczak, K.; Kaiser, M.; Kobychev, V.; Korablev, D.; Korga, G.; Kornoukhov, V.; Kryn, D.; Lachenmaier, T.; Lasserre, T.; Laubenstein, M.; Lehnert, T.; Link, J.; Litvinovich, E.; Lombardi, F.; Lombardi, P.; Ludhova, L.; Lukyanchenko, G.; Machulin, I.; Manecki, S.; Maneschg, W.; Marcocci, S.; Maricic, J.; Mention, G.; Meroni, E.; Meyer, M.; Miramonti, L.; Misiaszek, M.; Montuschi, M.; Mosteiro, P.; Muratova, V.; Musenich, R.; Neumair, B.; Oberauer, L.; Obolensky, M.; Ortica, F.; Pallavicini, M.; Papp, L.; Perasso, L.; Pocar, A.; Ranucci, G.; Razeto, A.; Re, A.; Romani, A.; Roncin, R.; Rossi, C.; Rossi, N.; Schönert, S.; Scola, L.; Semenov, D.; Simgen, H.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Sukhotin, S.; Suvorov, Y.; Tartaglia, R.; Testera, G.; Thurn, J.; Toropova, M.; Veyssière, C.; Vivier, M.; Unzhakov, E.; Vogelaar, R. B.; von Feilitzsch, F.; Wang, H.; Weinz, S.; Winter, J.; Wojcik, M.; Wurm, M.; Yokley, Z.; Zaimidoroga, O.; Zavatarelli, S.; Zuber, K.; Zuzel, G.

    2016-02-01

    In order to perform a resolutive measurement to clarify the neutrino anomalies and to observe possible short distance neutrino oscillations, the SOX (Short distance neutrino Oscillations with BoreXino) experiment is under construction. In the first phase, a 100 kCi 144Ce-144Pr antineutrino source will be placed under the Borexino detector at the Laboratori Nazionali del Gran Sasso (LNGS), in center of Italy, and the rate measurement of the antineutrino events, observed by the very low radioactive background Borexino detector, will be compared with the high precision (< 1%) activity measurement performed by two calorimeters. The source will be embedded in a 19 mm thick tungsten alloy shield and both the calorimeters have been conceived for measuring the thermal heat absorbed by a water flow. In this report the design of the calorimeters will be described in detail and very preliminary results will be also shown.

  13. High precision momentum calibration of the magnetic spectrometers at MAMI for hypernuclear binding energy determination

    NASA Astrophysics Data System (ADS)

    Margaryan, A.; Annand, J. R. M.; Achenbach, P.; Ajvazyan, R.; Elbakyan, H.; Montgomery, R.; Nakamura, S. N.; Pochodzalla, J.; Schulz, F.; Toyama, Y.; Zhamkochyan, S.

    2017-02-01

    We propose a new method for absolute momentum calibration of magnetic spectrometers used in nuclear physics, using the time-of-flight (TOF) differences of pairs of particles with different masses. In cases where the flight path is not known, a calibration can be determined by using the TOF differences of two pair combinations of three particles. A Cherenkov detector, read out by a radio frequency photomultiplier tube, is considered as the high-resolution and highly stable TOF detector. By means of Monte Carlo simulations it is demonstrated that the magnetic spectrometers at the MAMI electron-scattering facility can be calibrated absolutely with an accuracy δp / p ≤10-4 , which will be crucial for high precision determination of hypernuclear masses.

  14. Design and control of a high precision drive mechanism

    NASA Astrophysics Data System (ADS)

    Pan, Bo; He, Yongqiang; Wang, Haowei; Zhang, Shuyang; Zhang, Donghua; Wei, Xiaorong; Jiang, Zhihong

    2017-01-01

    This paper summarizes the development of a high precision drive mechanism (HPDM) for space application, such as the directional antenna, the laser communication device, the mobile camera and other pointing mechanisms. In view of the great practical significance of high precision drive system, control technology for permanent magnet synchronous motor (PMSM) servo system is also studied and a PMSM servo controller is designed in this paper. And the software alignment was applied to the controller to eliminate the steady error of the optical encoder, which helps to realize the 1 arcsec (1σ) control precision. To assess its capabilities, the qualification environment testing including the thermal vacuum cycling testing, and the sinusoidal and random vibration were carried out. The testing results show that the performance of the HPDM is almost the same between the former and the end of each testing.

  15. Design of high-precision ranging system for laser fuze

    NASA Astrophysics Data System (ADS)

    Chen, Shanshan; Zhang, He; Xu, Xiaobin

    2016-10-01

    According to the problem of the high-precision ranging in the circumferential scanning probe laser proximity fuze, a new type of pulsed laser ranging system has been designed. The laser transmitting module, laser receiving module and ranging processing module have been designed respectively. The factors affecting the ranging accuracy are discussed. And the method of improving the ranging accuracy is studied. The high-precision ranging system adopts the general high performance microprocessor C8051FXXX as the core. And the time interval measurement chip TDC-GP21 was used to implement the system. A PCB circuit board was processed to carry on the experiment. The results of the experiment prove that a centimeter level accuracy ranging system has been achieved. The works can offer reference for ranging system design of the circumferential scanning probe laser proximity fuze.

  16. High-precision spectroscopy of hydrogen molecular ions

    NASA Astrophysics Data System (ADS)

    Zhong, Zhen-Xiang; Tong, Xin; Yan, Zong-Chao; Shi, Ting-Yun

    2015-05-01

    In this paper, we overview recent advances in high-precision structure calculations of the hydrogen molecular ions ( and HD+), including nonrelativistic energy eigenvalues and relativistic and quantum electrodynamic corrections. In combination with high-precision measurements, it is feasible to precisely determine a molecular-based value of the proton-to-electron mass ratio. An experimental scheme is presented for measuring the rovibrational transition frequency (v,L) : (0,0) → (6,1) in HD+, which is currently underway at the Wuhan Institute of Physics and Mathematics. Project supported by the National Natural Science Foundation of China (Grants Nos. 11474316, 11004221, 10974224, and 11274348), the “Hundred Talent Program” of Chinese Academy of Sciences. Yan Zong-Chao was supported by NSERC, SHARCnet, ACEnet of Canada, and the CAS/SAFEA International Partnership Program for Creative Research Teams.

  17. High-precision Photogrammetric Surface Figure Measurements under Cryogenic Environment

    NASA Astrophysics Data System (ADS)

    Lou, Z.; Qian, Y.; Fan, S. H.; Liu, C. R.; Wang, H. R.; Zuo, Y. X.; Cheng, J. Q.; Yang, J.

    2016-01-01

    Limited by the working temperature of the measurement equipments, most of the high-precision surface figure measurement techniques cannot be applied under a cryogenic environment. This paper reports the first attempt to measure the surface figure of a high-precision terahertz reflector panel under low temperatures based on photogrammetry. The measurement employs a high resolution industrial camera sitting on an automatic experimental platform which enables photos been taken in an automatic fashion inside a climate chamber. A repeatable accuracy of 2.1 μm rms is achieved under the cryogenic environment. Furthermore, surface figure measured by a three-coordinate measuring machine under room temperature is used to calibrate the thickness variation of the paper targets. By this technique, the surface figure of an aluminum prototype panel of the 5 meter Dome A Terahertz Telescope (DATE5) is measured from room temperature down to -55°C.

  18. High Precision Measurement of the ^19Ne Lifetime

    NASA Astrophysics Data System (ADS)

    Broussard, Leah; Back, H. O.; Boswell, M. S.; Crowell, A. S.; Howell, C. R.; Kidd, M. F.; Pattie, R. W., Jr.; Young, A. R.; Dendooven, P. G.; Giri, G. S.; van der Hoek, D. J.; Jungmann, K.; Kruithof, W. L.; Onderwater, C. J. G.; Santra, B.; Shidling, P. D.; Sohani, M.; Versolota, O. O.; Willmann, L.; Wilschut, H. W.

    2009-10-01

    Recently, a rigorous review of the T=12 mirror transitions has identified several systems which can contribute to high precision tests exploring deviations from the Standard Model's description of the electroweak interaction. Arguably, one of the best candidates is the &+circ; decay of ^19Ne to ^19F. In this system, the main contribution to the uncertainty of extracted Standard Model parameters is due to the measured value of the lifetime of the decay. In March 2009, a high precision measurement of the lifetime of ^19Ne was made by a collaboration between the Triangle Universities Nuclear Laboratory (TUNL) and the Kernfysisch Versneller Instituut (KVI) at the Trapped Radioactive Isotopes: Microlaboratories for Fundamental Physics (Triμp) facility. An overview of the experiment and preliminary results will be presented.

  19. Note: High precision measurements using high frequency gigahertz signals

    NASA Astrophysics Data System (ADS)

    Jin, Aohan; Fu, Siyuan; Sakurai, Atsunori; Liu, Liang; Edman, Fredrik; Pullerits, Tõnu; Öwall, Viktor; Karki, Khadga Jung

    2014-12-01

    Generalized lock-in amplifiers use digital cavities with Q-factors as high as 5 × 108 to measure signals with very high precision. In this Note, we show that generalized lock-in amplifiers can be used to analyze microwave (giga-hertz) signals with a precision of few tens of hertz. We propose that the physical changes in the medium of propagation can be measured precisely by the ultra-high precision measurement of the signal. We provide evidence to our proposition by verifying the Newton's law of cooling by measuring the effect of change in temperature on the phase and amplitude of the signals propagating through two calibrated cables. The technique could be used to precisely measure different physical properties of the propagation medium, for example, the change in length, resistance, etc. Real time implementation of the technique can open up new methodologies of in situ virtual metrology in material design.

  20. Note: High precision measurements using high frequency gigahertz signals.

    PubMed

    Jin, Aohan; Fu, Siyuan; Sakurai, Atsunori; Liu, Liang; Edman, Fredrik; Pullerits, Tõnu; Öwall, Viktor; Karki, Khadga Jung

    2014-12-01

    Generalized lock-in amplifiers use digital cavities with Q-factors as high as 5 × 10(8) to measure signals with very high precision. In this Note, we show that generalized lock-in amplifiers can be used to analyze microwave (giga-hertz) signals with a precision of few tens of hertz. We propose that the physical changes in the medium of propagation can be measured precisely by the ultra-high precision measurement of the signal. We provide evidence to our proposition by verifying the Newton's law of cooling by measuring the effect of change in temperature on the phase and amplitude of the signals propagating through two calibrated cables. The technique could be used to precisely measure different physical properties of the propagation medium, for example, the change in length, resistance, etc. Real time implementation of the technique can open up new methodologies of in situ virtual metrology in material design.

  1. Computer-Aided High Precision Verification Of Miniature Spring Structure

    NASA Astrophysics Data System (ADS)

    Bow, Sing T.; Wang, Da-hao; Chen, Tsung-sheng; Newell, Darrell E.

    1990-01-01

    A system is proposed for the high precision on-line verification of the minia-ture spring structure, including overall height, diameters of various coils as well as pitches between neighboring coils of the miniature conical springs. High preci-sion measurements without physical contact and short processing time are achieved. Deformations of any kind on the conical springs can be identified even from the worst viewing direction.

  2. System and method for high precision isotope ratio destructive analysis

    DOEpatents

    Bushaw, Bruce A; Anheier, Norman C; Phillips, Jon R

    2013-07-02

    A system and process are disclosed that provide high accuracy and high precision destructive analysis measurements for isotope ratio determination of relative isotope abundance distributions in liquids, solids, and particulate samples. The invention utilizes a collinear probe beam to interrogate a laser ablated plume. This invention provides enhanced single-shot detection sensitivity approaching the femtogram range, and isotope ratios that can be determined at approximately 1% or better precision and accuracy (relative standard deviation).

  3. Dipole model analysis of high precision HERA data

    NASA Astrophysics Data System (ADS)

    Luszczak, A.; Kowalski, H.

    2014-04-01

    We analyze, within a dipole model, the inclusive deep inelastic scattering cross section data, obtained from the combination of the measurements of the H1 and ZEUS experiments performed at the HERA collider. We show that these high precision data are very well described within the dipole model framework, which is complemented with valence quark structure functions. We discuss the properties of the gluon density obtained in this way.

  4. High-Precision Direct Method for the Radiative Transfer Problems

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Hou, Su-Qing; Yang, Ping; Wu, Kai-Su

    2013-06-01

    It is the main aim of this paper to investigate the numerical methods of the radiative transfer equation. Using the five-point formula to approximate the differential part and the Simpson formula to substitute for integral part respectively, a new high-precision numerical scheme, which has 4-order local truncation error, is obtained. Subsequently, a numerical example for radiative transfer equation is carried out, and the calculation results show that the new numerical scheme is more accurate.

  5. High precision radial velocities: the case for NIR.

    NASA Astrophysics Data System (ADS)

    Carleo, I.; Gratton, R.

    In the context of the preparation for the high resolution spectrograph HIRES for E-ELT, we are studying the possibility to derive high-precision radial velocities (RV) on a prototype:GIANO, the near-infrared (NIR) echelle spectrograph now available at the Telescopio Nazionale Galileo. Radial velocities measured from near-infrared spectra are a potential tool to search for extrasolar planets around cool stars. High resolution infrared spectrographs now available are reaching the high precision of visible instruments, with a constant improvement over time. In particular, no other IR instruments have GIANO's capability to cover the entire NIR wavelength range. We have developed an ensemble of IDL procedures to measure high precision radial velocities on GIANO spectra. Taking into account the achieved precisions with GIANO, we constrain the sample of targets for which GIANO is better than HARPS-N, but with the advent of GIARPS (GIANO+HARPS-N), GIANO will improve its performances and include a much larger sample of stars. The NIR range is the future of RV measurements, especially because the jitter due to the star surface activities is reduced in the NIR. As a consequence, HIRES working in NIR range might be very useful, and for a wide range of cases, it will be more efficient than HIRES working in the visible range, for detection and characterization of planets using radial velocity technique.

  6. Fabrication and metrology of high-precision freeform surfaces

    NASA Astrophysics Data System (ADS)

    Supranowitz, Chris; Dumas, Paul; Nitzsche, Tobias; DeGroote Nelson, Jessica; Light, Brandon B.; Medicus, Kate; Smith, Nathan

    2013-09-01

    Freeform applications are growing and include helmet-mounted displays, conformal optics (e.g. windows integrated into airplane wings), and those requiring the extreme precision of EUV. These non-rotationally symmetric surfaces pose challenges to optical fabrication, mostly in the areas of polishing and metrology. The varying curvature of freeform surfaces drives the need for smaller, more "conformal", tools for polishing and reference beams for interferometry. In this paper, we present fabrication results of a high-precision freeform surface. We will discuss the total manufacturing process, including generation, pre-polishing, MRF®, and metrology, highlighting the capabilities available in today's optical fabrication companies.

  7. High-precision measurements of global stellar magnetic fields

    NASA Astrophysics Data System (ADS)

    Plachinda, S. I.

    2014-06-01

    This paper presents a brief history of the development of devices and techniques for high-precision measurements of stellar magnetic fields. Two main approaches for the processing of spectral-polarimetric observations are described: the method of least-squares deconvolution (LSD), which is used to find a mean-weighted average of the normalized polarization profile using a set of spectral lines, and a method in which each individual spectral line is used to determine the magnetic field, viz., the single line method (SL). The advantages and disadvantages of the LSD and SL methods are discussed.

  8. High precision photon flux determination for photon tagging experiments

    SciTech Connect

    Teymurazyan, A.; Ahmidouch, A.; Ambrozewicz, P.; Asratyan, A.; Baker, K.; Benton, L.; Burkert, V.; Clinton, E.; Cole, P.; Collins, P.; Dale, D.; Danagoulian, S.; Davidenko, G.; Demirchyan, R.; Deur, A.; Dolgolenko, A.; Dzyubenko, G.; Ent, R.; Evdokimov, A.; Feng, J.; Gabrielyan, M.; Gan, L.; Gasparian, A.; Glamazdin, A.; Goryachev, V.; Hardy, K.; He, J.; Ito, M.; Jiang, L.; Kashy, D.; Khandaker, M.; Kolarkar, A.; Konchatnyi, M.; Korchin, A.; Korsch, W.; Kosinov, O.; Kowalski, S.; Kubantsev, M.; Kubarovsky, V.; Larin, I.; Lawrence, D.; Li, X.; Martel, P.; Matveev, V.; McNulty, D.; Mecking, B.; Milbrath, B.; Minehart, R.; Miskimen, R.; Mochalov, V.; Nakagawa, I.; Overby, S.; Pasyuk, E.; Payen, M.; Pedroni, R.; Prok, Y.; Ritchie, B.; Salgado, C.; Shahinyan, A.; Sitnikov, A.; Sober, D.; Stepanyan, S.; Stevens, W.; Underwood, J.; Vasiliev, A.; Vishnyakov, V.; Wood, M.; Zhou, S.

    2014-12-01

    The Jefferson Laboratory PrimEx Collaboration has developed and implemented a method to control the tagged photon flux in photoproduction experiments at the 1% level over the photon energy range from 4.9 to 5.5 GeV. This method has been successfully implemented in a high precision measurement of the neutral pion lifetime. Here, we outline the experimental equipment and the analysis techniques used to accomplish this. These include the use of a total absorption counter for absolute flux calibration, a pair spectrometer for online relative flux monitoring, and a new method for post-bremsstrahlung electron counting.

  9. GENERATION AND CONTROL OF HIGH PRECISION BEAMS AT LEPTON ACCELERATORS

    SciTech Connect

    Yu-Chiu Chao

    2007-06-25

    Parity violation experiments require precision manipulation of helicity-correlated beam coordinates on target at the nm/nrad-level. Achieving this unprecedented level of control requires a detailed understanding of the particle optics and careful tuning of the beam transport to keep anomalies from compromising the design adiabatic damping. Such efforts are often hindered by machine configuration and instrumentation limitations at the low energy end. A technique has been developed at CEBAF including high precision measurements, Mathematica-based analysis for obtaining corrective solutions, and control hardware/software developments for realizing such level of control at energies up to 5 GeV.

  10. Multidimensional Image Analysis for High Precision Radiation Therapy.

    PubMed

    Arimura, Hidetaka; Soufi, Mazen; Haekal, Mohammad

    2017-01-01

    High precision radiation therapy (HPRT) has been improved by utilizing conventional image engineering technologies. However, different frameworks are necessary for further improvement of HPRT. This review paper attempted to define the multidimensional image and what multidimensional image analysis is, which may be feasible for increasing the accuracy of HPRT. A number of researches in radiation therapy field have been introduced to understand the multidimensional image analysis. Multidimensional image analysis could greatly assist clinical staffs in radiation therapy planning, treatment, and prediction of treatment outcomes.

  11. High precision applications of the global positioning system

    NASA Technical Reports Server (NTRS)

    Lichten, Stephen M.

    1991-01-01

    The Global Positioning System (GPS) is a constellation of U.S. defense navigation satellites which can be used for military and civilian positioning applications. A wide variety of GPS scientific applications were identified and precise positioning capabilities with GPS were already demonstrated with data available from the present partial satellite constellation. Expected applications include: measurements of Earth crustal motion, particularly in seismically active regions; measurements of the Earth's rotation rate and pole orientation; high-precision Earth orbiter tracking; surveying; measurements of media propagation delays for calibration of deep space radiometric data in support of NASA planetary missions; determination of precise ground station coordinates; and precise time transfer worldwide.

  12. Strategies for high-precision Global Positioning System orbit determination

    NASA Technical Reports Server (NTRS)

    Lichten, Stephen M.; Border, James S.

    1987-01-01

    Various strategies for the high-precision orbit determination of the GPS satellites are explored using data from the 1985 GPS field test. Several refinements to the orbit determination strategies were found to be crucial for achieving high levels of repeatability and accuracy. These include the fine tuning of the GPS solar radiation coefficients and the ground station zenith tropospheric delays. Multiday arcs of 3-6 days provided better orbits and baselines than the 8-hr arcs from single-day passes. Highest-quality orbits and baselines were obtained with combined carrier phase and pseudorange solutions.

  13. Future high precision experiments and new physics beyond Standard Model

    SciTech Connect

    Luo, Mingxing

    1993-04-01

    High precision (< 1%) electroweak experiments that have been done or are likely to be done in this decade are examined on the basis of Standard Model (SM) predictions of fourteen weak neutral current observables and fifteen W and Z properties to the one-loop level, the implications of the corresponding experimental measurements to various types of possible new physics that enter at the tree or loop level were investigated. Certain experiments appear to have special promise as probes of the new physics considered here.

  14. Future high precision experiments and new physics beyond Standard Model

    SciTech Connect

    Luo, Mingxing.

    1993-01-01

    High precision (< 1%) electroweak experiments that have been done or are likely to be done in this decade are examined on the basis of Standard Model (SM) predictions of fourteen weak neutral current observables and fifteen W and Z properties to the one-loop level, the implications of the corresponding experimental measurements to various types of possible new physics that enter at the tree or loop level were investigated. Certain experiments appear to have special promise as probes of the new physics considered here.

  15. High-precision HST proper motions of globular clusters

    NASA Astrophysics Data System (ADS)

    Bellini, A.

    Photometric and spectroscopic studies over the last 15 years have revolutionized our understanding of globular clusters (GCs). We now know that essentially all GCs host multiple stellar populations that can be identified along all evolutionary sequences and are characterized by differences in light elements, He, and sometimes Fe. These findings present a number of formidable challenges for the study of the formation and evolution of GCs. The internal kinematics of multiple stellar populations is a fundamental piece of the puzzle and high-precision proper motions are the key tool to shed light on many open questions regarding GCs.

  16. High-precision micro/nano-scale machining system

    DOEpatents

    Kapoor, Shiv G.; Bourne, Keith Allen; DeVor, Richard E.

    2014-08-19

    A high precision micro/nanoscale machining system. A multi-axis movement machine provides relative movement along multiple axes between a workpiece and a tool holder. A cutting tool is disposed on a flexible cantilever held by the tool holder, the tool holder being movable to provide at least two of the axes to set the angle and distance of the cutting tool relative to the workpiece. A feedback control system uses measurement of deflection of the cantilever during cutting to maintain a desired cantilever deflection and hence a desired load on the cutting tool.

  17. Recent developments in high precision vertex chambers at SLAC

    SciTech Connect

    Rust, D.R.

    1984-04-01

    Three detectors MARK II, MAC, AND HRS are using or planning small drift chambers placed as close as possible to the interaction print at PEP. There is also a program of development for a gaseous vertex detector for MARK II at SLC. All these programs are reviewed. 13 references.

  18. A General-Purpose Computer System for a Research and Development Center

    ERIC Educational Resources Information Center

    Fitzhugh, Robert J.; Glaser, Robert

    1975-01-01

    The evolution of a medium scale, general purpose, multi-language, time sharing computer system at the Learning Research and Development Center (LRDC) at the University of Pittsburgh is detailed. A strategy for the interfacing and control of laboratory devices is described with respect to several application environments; experimentation in the…

  19. A General Purpose Q-Measuring Circuit Using Pulse Ring-Down.

    PubMed

    Quine, Richard W; Mitchell, Deborah G; Eaton, Gareth R

    2011-02-01

    A general purpose pulsed microwave circuit was developed for the purpose of measuring resonator Q by the pulse ring-down method in EPR spectrometers without pulse capability. The circuit was installed and tested in a Bruker X-band EPR bridge. This method and circuit could be adapted for use in a variety of spectrometers operating at various microwave frequencies.

  20. 41 CFR 60-2.10 - General purpose and contents of affirmative action programs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... contents of affirmative action programs. 60-2.10 Section 60-2.10 Public Contracts and Property Management... EMPLOYMENT OPPORTUNITY, DEPARTMENT OF LABOR 2-AFFIRMATIVE ACTION PROGRAMS Purpose and Contents of Affirmative Action Programs § 60-2.10 General purpose and contents of affirmative action programs. (a) Purpose. (1...

  1. Selection and Use of General-Purpose Programming Languages--Overview. Volume 1.

    ERIC Educational Resources Information Center

    Cugini, John V.

    This study presents a review of selection factors for the seven major general-purpose programming languages: Ada, BASIC, C, COBOL, FORTRAN, PASCAL, and PL/I. The factors covered include not only the logical operations within each language, but also the advantages and disadvantages stemming from the current computing environment, e.g., software…

  2. 41 CFR 60-2.10 - General purpose and contents of affirmative action programs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 1 2014-07-01 2014-07-01 false General purpose and contents of affirmative action programs. 60-2.10 Section 60-2.10 Public Contracts and Property Management... EMPLOYMENT OPPORTUNITY, DEPARTMENT OF LABOR 2-AFFIRMATIVE ACTION PROGRAMS Purpose and Contents of...

  3. Generating fractal-like surfaces on general purpose mesh-connected computers

    NASA Technical Reports Server (NTRS)

    Wainer, Michael

    1988-01-01

    Realistic images of natural surfaces are often generated using computationally expensive stochastic modeling techniques. Here a parallel procedure to generate such models is presented. The target machines are general-purpose mesh-connected computers. The complexity of the procedure is similar to that of a proposed special-purpose parallel fractal generator.

  4. Comparative Analysis of Leasing versus Buying General Purpose Vehicles (Sedan) in the Korean Air Force

    DTIC Science & Technology

    2002-03-01

    COMPARATIVE ANALYSIS OF LEASING VERSUS BUYING GENERAL PURPOSE VEHICLES (SEDAN) IN THE KOREAN AIR FORCE...leasing versus buying vehicle study started from the recognition of this situation in which ROKAF needs an efficient and effective vehicle procurement...versus buying vehicles , which has been used in buying versus leasing decision. This research analyzed two variables, logistics benefits and costs, and

  5. High precision capacitive beam phase probe for KHIMA project

    NASA Astrophysics Data System (ADS)

    Hwang, Ji-Gwang; Yang, Tae-Keun; Forck, Peter

    2016-11-01

    In the medium energy beam transport (MEBT) line of KHIMA project, a high precision beam phase probe monitor is required for a precise tuning of RF phase and amplitude of Radio Frequency Quadrupole (RFQ) accelerator and IH-DTL linac. It is also used for measuring a kinetic energy of ion beam by time-of-flight (TOF) method using two phase probes. The capacitive beam phase probe has been developed. The electromagnetic design of the high precision phase probe was performed to satisfy the phase resolution of 1° (@200 MHz). It was confirmed by the test result using a wire test bench. The measured phase accuracy of the fabricated phase probe is 1.19 ps. The pre-amplifier electronics with the 0.125 ∼ 1.61 GHz broad-band was designed and fabricated for amplifying the signal strength. The results of RF frequency and beam energy measurement using a proton beam from the cyclotron in KIRAMS is presented.

  6. Electric Quadrupole Transition Measurements of Hydrogen Molecule with High Precision

    NASA Astrophysics Data System (ADS)

    Cheng, Cun-Feng; Wang, Jin; Tan, Yan; Liu, An-Wen; Hu, Shui-Ming

    2013-06-01

    Molecular hydrogen is the most fundamental, and the only neutral molecule expected to be both calculated and measured with extremely high accuracy. High-precision measurements of its spectroscopy, especially the levels at the electric ground state, play an important role in the examination of precise quantum chemistry calculations and some fundamental physical constants. In the infrared region, H_2, being a homonuclear diatomic molecule, only has very weak electric quadrupole transitions. We established a new spectroscopy approach with ultra-high precision and sensitivity as well, based on a laser-locked cavity ring-down spectrometer. An equivalent absorption path-length of thousands of kilometers and a frequency precision of 10^{-5} cm^{-1} have been achieved. Ro-vibrational spectra of the second overtone of H_2 have been recorded. The obtained results will provide a direct examination of the high-accuracy quantum theory. It also shades light on the determination of fundamental physical constants such as the electron/proton mass ratio in a molecular system.

  7. Automated high precision secondary pH measurements

    NASA Astrophysics Data System (ADS)

    Bastkowski, F.; Jakobsen, P. T.; Stefan, F.; Kristensen, H. B.; Jensen, H. D.; Kawiecki, R.; Wied, C. E.; Kauert, A.; Seidl, B.; Spitzer, P.; Eberhardt, R.; Adel, B.

    2013-04-01

    A new setup for high precision, automated secondary pH measurements together with a reference measurement procedure has been developed and tested in interlaboratory comparisons using buffers pH 4.005, pH 7.000, and pH 10.012 at 25 °C and 37 °C. Using primary buffers as standards, a standard uncertainty in pH better than 0.005 can be reached. The central measuring device is a one piece, thermostatted cell of PFA (perfluoroalkoxy) with a built-in Hamilton® Single Pore™ Glass electrode. Due to its flow-through principle this device allows pH measurements with low consumption of measurement solutions. The very hydrophobic and smooth PFA as construction material facilitates complete emptying of the cell. Furthermore, the tempering unit affords very precise temperature control and hence contributes to the low target uncertainty of the produced secondary buffer solutions. Use of a symmetric measurement sequence and the two point calibration was sufficient to reach high precision and accuracy.

  8. Thermal design and flight validation for high precision camera

    NASA Astrophysics Data System (ADS)

    Meng, Henghui; Sun, Lixia; Zhang, Chuanqiang; Geng, Liyin

    2015-10-01

    High precision camera, designed for advanced optical system, with a wide field of vision, high resolution and fast response, has a wild range of applications. As the main payload for spacecraft, the optical remote sensor is mounted exposed to the space, which means it should have a reliable optical performance in harsh space environment during lifetime. Because of the special optical characteristic, imaging path should be accurate, and less thermal deformation for the optical parts is required in the working process, so the high precision camera has a high level requirement for temperature. High resolution space camera is generally required to own the capability of adapting to space thermal environments. The flexible satellite's change of rolling attitude affects the temperature distribution of the camera and makes a difference to optical performance. The thermal control design of space camera is presented, and analysis the temperature data in orbit to prove the thermal design correct. It is proved that the rolling attitude has more influence on outer parts and less influence on inner parts, and active thermal control can weaken the influence of rolling attitude.

  9. High-Precision Computation: Mathematical Physics and Dynamics

    SciTech Connect

    Bailey, D. H.; Barrio, R.; Borwein, J. M.

    2010-04-01

    At the present time, IEEE 64-bit oating-point arithmetic is suficiently accurate for most scientic applications. However, for a rapidly growing body of important scientic computing applications, a higher level of numeric precision is required. Such calculations are facilitated by high-precision software packages that include high-level language translation modules to minimize the conversion e ort. This pa- per presents a survey of recent applications of these techniques and provides someanalysis of their numerical requirements. These applications include supernova simulations, climate modeling, planetary orbit calculations, Coulomb n-body atomic systems, studies of the one structure constant, scattering amplitudes of quarks, glu- ons and bosons, nonlinear oscillator theory, experimental mathematics, evaluation of orthogonal polynomials, numerical integration of ODEs, computation of periodic orbits, studies of the splitting of separatrices, detection of strange nonchaotic at- tractors, Ising theory, quantum held theory, and discrete dynamical systems. We conclude that high-precision arithmetic facilities are now an indispensable compo- nent of a modern large-scale scientic computing environment.

  10. PHASES High-Precision Differential Astrometry of δ Equulei

    NASA Astrophysics Data System (ADS)

    Muterspaugh, Matthew W.; Lane, Benjamin F.; Konacki, Maciej; Burke, Bernard F.; Colavita, M. M.; Kulkarni, S. R.; Shao, M.

    2005-12-01

    Delta Equulei is among the most well-studied nearby binary star systems. Results of its observation have been applied to a wide range of fundamental studies of binary systems and stellar astrophysics. It is widely used to calibrate and constrain theoretical models of the physics of stars. We report 27 high-precision differential astrometry measurements of δ Equ from the Palomar High-precision Astrometric Search for Exoplanet Systems (PHASES). The median size of the minor axes of the uncertainty ellipses for these measurements is 26 μas. These data are combined with previously published radial velocity data and other previously published differential astrometry measurements using other techniques to produce a combined model for the system orbit. The distance to the system is determined to within one twentieth of a parsec, and the component masses are determined at the level of a percent. The constraints on masses and distance are limited by the precisions of the radial velocity data; we outline plans to improve this deficiency and discuss the outlook for further study of this binary.

  11. A High Precision Terahertz Wave Image Reconstruction Algorithm

    PubMed Central

    Guo, Qijia; Chang, Tianying; Geng, Guoshuai; Jia, Chengyan; Cui, Hong-Liang

    2016-01-01

    With the development of terahertz (THz) technology, the applications of this spectrum have become increasingly wide-ranging, in areas such as non-destructive testing, security applications and medical scanning, in which one of the most important methods is imaging. Unlike remote sensing applications, THz imaging features sources of array elements that are almost always supposed to be spherical wave radiators, including single antennae. As such, well-developed methodologies such as Range-Doppler Algorithm (RDA) are not directly applicable in such near-range situations. The Back Projection Algorithm (BPA) can provide products of high precision at the the cost of a high computational burden, while the Range Migration Algorithm (RMA) sacrifices the quality of images for efficiency. The Phase-shift Migration Algorithm (PMA) is a good alternative, the features of which combine both of the classical algorithms mentioned above. In this research, it is used for mechanical scanning, and is extended to array imaging for the first time. In addition, the performances of PMA are studied in detail in contrast to BPA and RMA. It is demonstrated in our simulations and experiments described herein that the algorithm can reconstruct images with high precision. PMID:27455269

  12. High Precision Photometry for the K2 Mission

    NASA Astrophysics Data System (ADS)

    Huang, Xu; Soares-Furtado, Melinda; Penev, Kaloyan; Hartman, Joel; Bakos, Gaspar; Bhatti, Waqas; Domsa, Istvan; de Val-Borro, Miguel

    2015-12-01

    The two reaction wheel K2 mission brings new challenges for the data reduction processes. We developed a reduction pipeline for extracting high precision photometry from the K2 dataset and we use this pipeline to generate light curves for the K2 Campaign 0 super-stamps and K2 Campaign 1 target pixel dataset. Key to our reduction technique is the derivation of global astrometric solutions from the target stamps from which accurate centroids are passed on for high precision photometry extraction. We also implemented the image subtraction method to reduce the K2 Campaign 0 super-stamps containing open clusters M35 and NGC2158. We extract target light curvesfor sources from a combined UCAC4 and EPIC catalogue -- this includes not only primary targets of the K2 Mission, but also other stars that happen to fall on the pixel stamps. Our astrometric solutions achieve a median residual of ~0.127". For bright stars, our best 6.5 hour precision for raw light curves is ~20 parts per million (ppm). For our detrended light curves, the best 6.5 hour precision achieved is ~15 ppm. We show that our detrended light curves have fewer systematic effects (or trends, or red-noise) than light curves produced by other groups from the same observations. We highlight the measurements of rotation curves using the K2 light curves of stars within open cluster M35 and NGC2158.

  13. High-precision camera distortion measurements with a ``calibration harp''

    NASA Astrophysics Data System (ADS)

    Tang, Zhongwei; Grompone von Gioi, Rafael; Monasse, Pascal; Morel, Jean-Michel

    2012-10-01

    This paper addresses the high precision measurement of the distortion of a digital camera from photographs. Traditionally, this distortion is measured from photographs of a flat pattern which contains aligned elements. Nevertheless, it is nearly impossible to fabricate a very flat pattern and to validate its flatness. This fact limits the attainable measurable precisions. In contrast, it is much easier to obtain physically very precise straight lines by tightly stretching good quality strings on a frame. Taking literally "plumb-line methods", we built a "calibration harp" instead of the classic flat patterns to obtain a high precision measurement tool, demonstrably reaching 2/100 pixel precisions. The harp is complemented with the algorithms computing automatically from harp photographs two different and complementary lens distortion measurements. The precision of the method is evaluated on images corrected by state-of-the-art distortion correction algorithms, and by popular software. Three applications are shown: first an objective and reliable measurement of the result of any distortion correction. Second, the harp permits to control state-of-the art global camera calibration algorithms: It permits to select the right distortion model, thus avoiding internal compensation errors inherent to these methods. Third, the method replaces manual procedures in other distortion correction methods, makes them fully automatic, and increases their reliability and precision.

  14. High-precision Photogrammetric Surface Figure Measurements under Cryogenic Environment

    NASA Astrophysics Data System (ADS)

    Zheng, Lou; Yuan, Qian; Sheng-hong, Fan; Chang-ru, Liu; Hai-ren, Wang; Ying-xi, Zuo; Jin-quan, Cheng; Ji, Yang

    2017-01-01

    Limited by the working temperature of the test equipment, most of high-precision surface figure measurement techniques cannot be put into application under a cryogenic environment. This paper reports the first attempt to measure the surface figure of a high-precision terahertz reflector panel under low temperatures based on photogrammetry. The measurement employs a high-resolution industrial camera sitting on the automatic testing platform which enables photos been taken in an automatic fashion inside a climate chamber. A repeatable accuracy of 2.1 μm (rms) is achieved under the cryogenic environment. Furthermore, the surface figure measured by a three-coordinate measuring machine under the room temperature is used to calibrate the thickness differences of the targets. By this technique, the surface figure of an aluminum prototype panel of the 5 meter Dome A Terahertz Telescope (DATE5) is measured from room temperature down to -55°C to obtain the rule of variation of surface deformation of the panel under low temperatures.

  15. High-precision branching ratio measurement for the superallowed {beta}{sup +} emitter {sup 62}Ga

    SciTech Connect

    Finlay, P.; Svensson, C. E.; Bandyopadhyay, D.; Grinyer, G. F.; Hyland, B.; Leach, K. G.; Phillips, A. A.; Schumaker, M. A.; Wong, J.; Ball, G. C.; Chakrawarthy, R. S.; Hackman, G.; Kanungo, R.; Morton, A. C.; Pearson, C. J.; Savajols, H.; Leslie, J. R.; Towner, I. S.; Austin, R. A. E.; Chaffey, A.

    2008-08-15

    A high-precision branching ratio measurement for the superallowed {beta}{sup +} decay of {sup 62}Ga was performed at the Isotope Separator and Accelerator (ISAC) radioactive ion beam facility. The 8{pi} spectrometer, an array of 20 high-purity germanium detectors, was employed to detect the {gamma} rays emitted following Gamow-Teller and nonanalog Fermi {beta}{sup +} decays of {sup 62}Ga, and the SCEPTAR plastic scintillator array was used to detect the emitted {beta} particles. Thirty {gamma} rays were identified following {sup 62}Ga decay, establishing the superallowed branching ratio to be 99.858(8)%. Combined with the world-average half-life and a recent high-precision Q-value measurement for {sup 62}Ga, this branching ratio yields an ft value of 3074.3{+-}1.1 s, making {sup 62}Ga among the most precisely determined superallowed ft values. Comparison between the superallowed ft value determined in this work and the world-average corrected Ft value allows the large nuclear-structure-dependent correction for {sup 62}Ga decay to be experimentally determined from the CVC hypothesis to better than 7% of its own value, the most precise experimental determination for any superallowed emitter. These results provide a benchmark for the refinement of the theoretical description of isospin-symmetry breaking in A{>=}62 superallowed decays.

  16. High precision (14 bit), high density (octal) analog to digital converter for spectroscopy applications

    NASA Astrophysics Data System (ADS)

    Subramaniam, E. T.; Jain, Mamta; Bhowmik, R. K.; Tripon, Michel

    2008-10-01

    Nuclear and particle physics experiments with large number of detectors require signal processing and data collection strategies that call for the ability to collect large amount of data while not sacrificing the precision and accuracy of the data being collected. This paper deals with the development of a high precision pulse peak detection, analog to digital converter (ADC) module with eight independent channels in plug-in daughter card motherboard model, best suited for spectroscopy experiments. This module provides multiple channels without cross-talk and of 14 bit resolution, while maintaining high density (each daughter card has an area of just 4.2″×0.51″) and exhibiting excellent integral nonlinearity (≤±2 mV or ±0.02% full scale reading) and differential nonlinearity (≤±1%). It was designed, developed and tested, in house, and gives added advantages of cost effectiveness and ease of maintenance.

  17. High precision (14 bit), high density (octal) analog to digital converter for spectroscopy applications.

    PubMed

    Subramaniam, E T; Jain, Mamta; Bhowmik, R K; Tripon, Michel

    2008-10-01

    Nuclear and particle physics experiments with large number of detectors require signal processing and data collection strategies that call for the ability to collect large amount of data while not sacrificing the precision and accuracy of the data being collected. This paper deals with the development of a high precision pulse peak detection, analog to digital converter (ADC) module with eight independent channels in plug-in daughter card motherboard model, best suited for spectroscopy experiments. This module provides multiple channels without cross-talk and of 14 bit resolution, while maintaining high density (each daughter card has an area of just 4.2(")x0.51(")) and exhibiting excellent integral nonlinearity (< or = +/-2 mV or +/-0.02% full scale reading) and differential nonlinearity (< or = +/-1%). It was designed, developed and tested, in house, and gives added advantages of cost effectiveness and ease of maintenance.

  18. An FPGA Based General Purpose DAQ Module for the KLOE-2 Experiment

    NASA Astrophysics Data System (ADS)

    Aloisio, A.; Branchini, P.; Budano, A.; Balla, A.; Beretta, M.; Ciambrone, P.; De Lucia, E.

    2011-12-01

    A general purpose FPGA based DAQ module has been developed based on a Virtex-4 FPGA. It is able to acquire up to 1024 different channels distributed over 10 slave cards. The module has an optical interface a RS-232 a USB and a Gigabit Interface. The KLOE-2 experiment is going to use it to collect data from the Inner tracker and the QCALT. An embedded processor (power pc 604) is present on the FPGA and a telnet server has been developed and installed. A new general purpose data taking system has been based on this module to acquire the Inner Tracker. The system is at the moment working at LNF (Laboratori Nazionali di Frascati).

  19. General purpose simulation system of the data management system for Space Shuttle mission 18

    NASA Technical Reports Server (NTRS)

    Bengtson, N. M.; Mellichamp, J. M.; Smith, O. C.

    1976-01-01

    A simulation program for the flow of data through the Data Management System of Spacelab and Space Shuttle was presented. The science, engineering, command and guidance, navigation and control data were included. The programming language used was General Purpose Simulation System V (OS). The science and engineering data flow was modeled from its origin at the experiments and subsystems to transmission from Space Shuttle. Command data flow was modeled from the point of reception onboard and from the CDMS Control Panel to the experiments and subsystems. The GN&C data flow model handled data between the General Purpose Computer and the experiments and subsystems. Mission 18 was the particular flight chosen for simulation. The general structure of the program is presented, followed by a user's manual. Input data required to make runs are discussed followed by identification of the output statistics. The appendices contain a detailed model configuration, program listing and results.

  20. Discrete-Event Execution Alternatives on General Purpose Graphical Processing Units

    SciTech Connect

    Perumalla, Kalyan S

    2006-01-01

    Graphics cards, traditionally designed as accelerators for computer graphics, have evolved to support more general-purpose computation. General Purpose Graphical Processing Units (GPGPUs) are now being used as highly efficient, cost-effective platforms for executing certain simulation applications. While most of these applications belong to the category of time-stepped simulations, little is known about the applicability of GPGPUs to discrete event simulation (DES). Here, we identify some of the issues & challenges that the GPGPU stream-based interface raises for DES, and present some possible approaches to moving DES to GPGPUs. Initial performance results on simulation of a diffusion process show that DES-style execution on GPGPU runs faster than DES on CPU and also significantly faster than time-stepped simulations on either CPU or GPGPU.

  1. The development of high precision carbon fiber composite mirror

    NASA Astrophysics Data System (ADS)

    Xu, Liang; Ding, Jiao-teng; Wang, Yong-jie; Xie, Yong-jie; Ma, Zhen; Fan, Xue-wu

    2016-10-01

    Due to low density, high stiffness, low thermal expansion coefficient, duplicate molding, etc., carbon fiber reinforced polymer (CFRP) is one of the potential materials of the optical mirror. The process developed for Φ300mm high precision CFRP mirror described in this paper. A placement tool used to improve laying accuracy up to ± 0.1°.A special reinforced cell structure designed to increase rigidity and thermal stability. Optical replication process adopted for surface modification of the carbon fiber composite mirror blank. Finally, surface accuracy RMS of Φ300mm CFRP mirror is 0.22μm, surface roughness Ra is about 2nm, and the thermal stability can achieve 13nm /°C from the test result. The research content is of some reference value in the infrared as well as visible light applications.

  2. Flight Test Performance of a High Precision Navigation Doppler Lidar

    NASA Technical Reports Server (NTRS)

    Pierrottet, Diego; Amzajerdian, Farzin; Petway, Larry; Barnes, Bruce; Lockard, George

    2009-01-01

    A navigation Doppler Lidar (DL) was developed at NASA Langley Research Center (LaRC) for high precision velocity measurements from a lunar or planetary landing vehicle in support of the Autonomous Landing and Hazard Avoidance Technology (ALHAT) project. A unique feature of this DL is that it has the capability to provide a precision velocity vector which can be easily separated into horizontal and vertical velocity components and high accuracy line of sight (LOS) range measurements. This dual mode of operation can provide useful information, such as vehicle orientation relative to the direction of travel, and vehicle attitude relative to the sensor footprint on the ground. System performance was evaluated in a series of helicopter flight tests over the California desert. This paper provides a description of the DL system and presents results obtained from these flight tests.

  3. Monolithic interferometer for high precision radial velocity measurements

    NASA Astrophysics Data System (ADS)

    Wan, Xiaoke; Ge, Jian; Wang, Ji; Lee, Brian

    2009-08-01

    In high precision radial velocity (RV) measurements for extrasolar planets searching and studies, a stable wide field Michelson interferometer is very critical in Exoplanet Tracker (ET) instruments. Adopting a new design, monolithic interferometers are homogenous and continuous in thermal expansion, and field compensation and thermal compensation are both satisfied. Interferometer design and fabrication are decrypted in details. In performance evaluations, field angle is typically 22° and thermal sensitivity is typically -1.7 x 10-6/°C, which corresponds to ~500 m/s /°C in RV scale. In interferometer stability monitoring using a wavelength stabilized laser source, phase shift data was continuously recorded for nearly seven days. Appling a frequent calibration every 30 minutes as in typical star observations, the interferometer instability contributes less than 1.4 m/s in RV error, in a conservative estimation.

  4. High-precision buffer circuit for suppression of regenerative oscillation

    NASA Technical Reports Server (NTRS)

    Tripp, John S.; Hare, David A.; Tcheng, Ping

    1995-01-01

    Precision analog signal conditioning electronics have been developed for wind tunnel model attitude inertial sensors. This application requires low-noise, stable, microvolt-level DC performance and a high-precision buffered output. Capacitive loading of the operational amplifier output stages due to the wind tunnel analog signal distribution facilities caused regenerative oscillation and consequent rectification bias errors. Oscillation suppression techniques commonly used in audio applications were inadequate to maintain the performance requirements for the measurement of attitude for wind tunnel models. Feedback control theory is applied to develop a suppression technique based on a known compensation (snubber) circuit, which provides superior oscillation suppression with high output isolation and preserves the low-noise low-offset performance of the signal conditioning electronics. A practical design technique is developed to select the parameters for the compensation circuit to suppress regenerative oscillation occurring when typical shielded cable loads are driven.

  5. High-precision thermal and electrical characterization of thermoelectric modules

    SciTech Connect

    Kolodner, Paul

    2014-05-15

    This paper describes an apparatus for performing high-precision electrical and thermal characterization of thermoelectric modules (TEMs). The apparatus is calibrated for operation between 20 °C and 80 °C and is normally used for measurements of heat currents in the range 0–10 W. Precision thermometry based on miniature thermistor probes enables an absolute temperature accuracy of better than 0.010 °C. The use of vacuum isolation, thermal guarding, and radiation shielding, augmented by a careful accounting of stray heat leaks and uncertainties, allows the heat current through the TEM under test to be determined with a precision of a few mW. The fractional precision of all measured parameters is approximately 0.1%.

  6. High Precision Assembly Line Synthesis for Molecules with Tailored Shapes

    PubMed Central

    Burns, Matthew; Essafi, Stephanie; Bame, Jessica R.; Bull, Stephanie P.; Webster, Matthew P.; Balieu, Sebastien; Dale, James W.; Butts, Craig P.; Harvey, Jeremy N.; Aggarwal, Varinder K.

    2014-01-01

    Molecular assembly lines, where molecules undergo iterative processes involving chain elongation and functional group manipulation are hallmarks of many processes found in Nature. We have sought to emulate Nature in the development of our own molecular assembly line through iterative homologations of boronic esters. Here we report a reagent (α-lithioethyl triispopropylbenzoate) which inserts into carbon-boron bonds with exceptionally high fidelity and stereocontrol. Through repeated iteration we have converted a simple boronic ester into a complex molecule (a carbon chain with ten contiguous methyl groups) with remarkably high precision over its length, its stereochemistry and therefore its shape. Different stereoisomers were targeted and it was found that they adopted different shapes (helical/linear) according to their stereochemistry. This work should now enable scientists to rationally design and create molecules with predictable shape, which could have an impact in all areas of molecular sciences where bespoke molecules are required. PMID:25209797

  7. Preparation of cold molecules for high-precision measurements

    NASA Astrophysics Data System (ADS)

    Wall, T. E.

    2016-12-01

    Molecules can be used to test fundamental physics. Such tests often require cold molecules for detailed spectroscopic analysis. Cooling internal degrees of freedom provides a high level of state-selectivity, with large populations in the molecular states of interest. Cold translational motion allows slow, bright beams to be created, allowing long interaction times. In this tutorial article we describe the common techniques for producing cold molecules for high-precision spectroscopy experiments. For each technique we give examples of its application in experiments that use molecular structure to probe fundamental physics, choosing one experiment in particular as a case study. We then discuss a number of new techniques, some currently under development, others proposed, that promise high flux sources of cold molecules applicable to precise spectroscopic tests of fundamental physics.

  8. High precision u/th dating of first Polynesian settlement.

    PubMed

    Burley, David; Weisler, Marshall I; Zhao, Jian-xin

    2012-01-01

    Previous studies document Nukuleka in the Kingdom of Tonga as a founder colony for first settlement of Polynesia by Lapita peoples. A limited number of radiocarbon dates are one line of evidence supporting this claim, but they cannot precisely establish when this event occurred, nor can they afford a detailed chronology for sequent occupation. High precision U/Th dates of Acropora coral files (abraders) from Nukuleka give unprecedented resolution, identifying the founder event by 2838±8 BP and documenting site development over the ensuing 250 years. The potential for dating error due to post depositional diagenetic alteration of ancient corals at Nukuleka also is addressed through sample preparation protocols and paired dates on spatially separated samples for individual specimens. Acropora coral files are widely distributed in Lapita sites across Oceania. U/Th dating of these artifacts provides unparalleled opportunities for greater precision and insight into the speed and timing of this final chapter in human settlement of the globe.

  9. A high precision semi-analytic mass function

    NASA Astrophysics Data System (ADS)

    Del Popolo, Antonino; Pace, Francesco; Le Delliou, Morgan

    2017-03-01

    In this paper, extending past works of Del Popolo, we show how a high precision mass function (MF) can be obtained using the excursion set approach and an improved barrier taking implicitly into account a non-zero cosmological constant, the angular momentum acquired by tidal interaction of proto-structures and dynamical friction. In the case of the ΛCDM paradigm, we find that our MF is in agreement at the 3% level to Klypin's Bolshoi simulation, in the mass range Mvir = 5 × 109 h‑1Msolar–‑5 × 1014 h‑1Msolar and redshift range 0 lesssim z lesssim 10. For z = 0 we also compared our MF to several fitting formulae, and found in particular agreement with Bhattacharya's within 3% in the mass range 1012–1016 h‑1Msolar. Moreover, we discuss our MF validity for different cosmologies.

  10. High precision variational calculations of few-electron atoms

    NASA Astrophysics Data System (ADS)

    Bubin, Sergiy

    2015-05-01

    High precision calculations of energy levels and other properties of small atoms and ions have been a subject of fruitful interplay between the experiment and theory. However, most calculation of spectroscopic accuracy, until recently, have been possible only for two- and three-electron systems. In this talk I will report on progress toward performing high accuracy calculations of larger atomic systems (up to four-six electrons). The results of benchmark quality are attainable with the use of variational expansions in terms of all-particle explicitly correlated Gaussians, whose nonlinear variational parameters are extensively optimized. I will demonstrate what level of accuracy is available today for few-electron atoms and discuss the issues that must be overcome in order to extend the capability of the method to even larger systems. This work has been supported by the Ministry of Education and Science of Kazakhstan.

  11. The importance of high-precision hadronic calorimetry to physics

    NASA Astrophysics Data System (ADS)

    Hauptman, John

    2016-11-01

    The reconstruction and high-precision measurement of the four-vectors of W and Z decays to quarks, which constitute nearly 70% of their decay branching fractions, are critical to a high efficiency and high quality experiment. Furthermore, it is crucial that the energy resolution, and consequently the resolution on the invariant mass of the two fragmenting quarks, is comparable to the energy-momentum resolution on the other particles of the standard model, in particular, electrons, photons, and muons, at energies around 100 GeV. I show that this “unification of resolutions” on all particles of the standard model is now in sight, and will lead to excellent physics at an electron-positron collider.

  12. A high-precision polarimeter for small telescopes

    NASA Astrophysics Data System (ADS)

    Bailey, Jeremy; Cotton, Daniel V.; Kedziora-Chudczer, Lucyna

    2017-02-01

    We describe Mini-HIPPI (Miniature HIgh Precision Polarimetric Instrument), a stellar polarimeter weighing just 650 gm but capable of measuring linear polarization to ∼10-5. Mini-HIPPI is based on the use of a Ferroelectric Liquid Crystal modulator. It can easily be mounted on a small telescope and allows us to study the polarization of bright stars at levels of precision which are hitherto largely unexplored. We present results obtained with Mini-HIPPI on a 35-cm telescope. Measurements of polarized standard stars are in good agreement with predicted values. Measurements of a number of bright stars agree well with those from other high-sensitivity polarimeters. Observations of the binary system Spica show polarization variability around the orbital cycle.

  13. Modular Gravitational Reference Sensor for High Precision Astronomical Space Missions

    NASA Astrophysics Data System (ADS)

    Sun, Ke-Xun; Allen, G.; Buchman, S.; Byer, R. L.; Conklin, J. W.; DeBra, D. B.; Gill, D.; Goh, A.; Higuchi, S.; Lu, P.; Robertson, N.; Swank, A.

    2006-12-01

    We review the progress in developing the Modular Gravitational Reference Sensor (modular GRS) [1], which was first proposed as a simplified core sensor for space gravitational wave detection missions. In a modular GRS, laser beam from the remote the sensor does not illuminate the proof mass directly. The internal measurement from housing to proof mass is separated from the external interferometry. A double side grating may further simplify the structure and may better preserve the measurement precision. We review the recent progress in developing modular GRS at Stanford. We have further studied optical sensing design that combines advantage of high precision interferometric measurement and robust optical shadow sensing scheme. We have made critical progress in optical measurement of the center of mass position of a spherical proof mass at a precision without costing the dynamic range while spinning. We have successfully demonstrated the feasibility of fabricating localized grating pattern onto the dielectric and gold materials. We have conducted an initial experiment of rf heterodyne of cavity reflection and thus lowered optical power than that in the direct detection. We have further studied UV LED that will be used for AC charge management experiment. The modular GRS will be an in-time, cost effective product for the advanced Laser Interferometric Space Antenna (LISA) and the Big Bang Observatory (BBO). [1] K. Sun, G. Allen, S. Buchman, D. DeBra, and R. L. Byer, “Advanced Architecture for High Precision Space Laser Interferometers”, 5th International LISA Symposium, ESTEC, Noordwijk, The Netherlands, 12-16 July 2004. Class. Quantum Grav. 22 (2005) S287-S296.

  14. MultiView High Precision VLBI Astrometry at Low Frequencies

    NASA Astrophysics Data System (ADS)

    Rioja, María J.; Dodson, Richard; Orosz, Gabor; Imai, Hiroshi; Frey, Sandor

    2017-03-01

    The arrival of the Square Kilometer Array (SKA) will revitalize all aspects of Very Long Baseline Interferometry (VLBI) astronomy at lower frequencies. In the last decade, there have been huge strides toward routinely achieving high precision VLBI astrometry at frequencies dominated by tropospheric contributions, most notably at 22 GHz, using advanced phase-referencing techniques. Nevertheless, to increase the capability for high precision astrometric measurements at low radio frequencies (<8 GHz), an effective calibration strategy of the systematic ionospheric propagation effects that is widely applicable is required. Observations at low frequencies are dominated by distinct direction-dependent ionospheric propagation errors, which place a very tight limit on the angular separation of a suitable phase-referencing calibrator. The MultiView technique holds the key to compensating for atmospheric spatial-structure errors, by using observations of multiple calibrators and two-dimensional interpolation in the visibility domain. In this paper we present the first demonstration of the power of MultiView using three calibrators, several degrees from the target, along with a comparative study of the astrometric accuracy between MultiView and phase-referencing techniques. MultiView calibration provides an order of magnitude improvement in astrometry with respect to conventional phase referencing, achieving ∼100 μas astrometry errors in a single epoch of observations, effectively reaching the thermal noise limit. MultiView will achieve its full potential with the enhanced sensitivity and multibeam capabilities of SKA and the pathfinders, which will enable simultaneous observations of the target and calibrators. Our demonstration indicates that the 10 μas goal of astrometry at ∼1.6 GHz using VLBI with SKA is feasible using the MultiView technique.

  15. High-precision photometry for K2 Campaign 1

    NASA Astrophysics Data System (ADS)

    Huang, C. X.; Penev, K.; Hartman, J. D.; Bakos, G. Á.; Bhatti, W.; Domsa, I.; de Val-Borro, M.

    2015-12-01

    The two reaction wheel K2 mission promises and has delivered new discoveries in the stellar and exoplanet fields. However, due to the loss of accurate pointing, it also brings new challenges for the data reduction processes. In this paper, we describe a new reduction pipeline for extracting high-precision photometry from the K2 data set, and present public light curves for the K2 Campaign 1 target pixel data set. Key to our reduction is the derivation of global astrometric solutions from the target stamps, from which accurate centroids are passed on for high-precision photometry extraction. We extract target light curves for sources from a combined UCAC4 and EPIC catalogue - this includes not only primary targets of the K2 campaign 1, but also any other stars that happen to fall on the pixel stamps. We provide the raw light curves, and the products of various detrending processes aimed at removing different types of systematics. Our astrometric solutions achieve a median residual of ˜0.127 arcsec. For bright stars, our best 6.5 h precision for raw light curves is ˜20 parts per million (ppm). For our detrended light curves, the best 6.5 h precision achieved is ˜15 ppm. We show that our detrended light curves have fewer systematic effects (or trends, or red-noise) than light curves produced by other groups from the same observations. Example light curves of transiting planets and a Cepheid variable candidate, are also presented. We make all light curves public, including the raw and detrended photometry, at http://k2.hatsurveys.org.

  16. Design of low-cost general purpose microcontroller based neuromuscular stimulator.

    PubMed

    Koçer, S; Rahmi Canal, M; Güler, I

    2000-04-01

    In this study, a general purpose, low-cost, programmable, portable and high performance stimulator is designed and implemented. For this purpose, a microcontroller is used in the design of the stimulator. The duty cycle and amplitude of the designed system can be controlled using a keyboard. The performance test of the system has shown that the results are reliable. The overall system can be used as the neuromuscular stimulator under safe conditions.

  17. The role of overset grids in the development of the general purpose CFD code

    NASA Technical Reports Server (NTRS)

    Belk, Davy M.

    1995-01-01

    A discussion of the strengths and weaknesses of overset composite grid and solution technology is given, along with a sampling of current work in the area. Major trends are identified, and the observation is made that generalized and hybridized overset methods provide a natural framework for combining disparate mesh types and physics models. Because of this, the author concludes that overset methods will be the foundation for the general purpose computational fluid dynamics programs of the future.

  18. A general-purpose balloon-borne pointing system for solar scientific instruments

    NASA Technical Reports Server (NTRS)

    Polites, M. E.

    1990-01-01

    A general purpose balloonborne pointing system for accommodating a wide variety of solar scientific instruments is described. It is designed for precise pointing, low cost, and quick launch. It offers the option of three-axis control, pitch-yaw-roll, or two-axis control, pitch-yaw, depending on the needs of the solar instrument. Simulation results are presented that indicate good pointing capability at Sun elevation angles ranging from 10 to 80 deg.

  19. Documentary table-top view of a comparison of the General Purpose Computers.

    NASA Image and Video Library

    1988-09-13

    S88-47513 (Aug 1988) --- The current and future versions of general purpose computers for Space Shuttle orbiters are represented in this frame. The two boxes on the left (AP101B) represent the current GPC configuration, with the input-output processor at far left and the central processing unit at its side. The upgraded version combines both elements in a single unit (far right, AP101S).

  20. Comparison of progressive addition lenses for general purpose and for computer vision: an office field study.

    PubMed

    Jaschinski, Wolfgang; König, Mirjam; Mekontso, Tiofil M; Ohlendorf, Arne; Welscher, Monique

    2015-05-01

    Two types of progressive addition lenses (PALs) were compared in an office field study: 1. General purpose PALs with continuous clear vision between infinity and near reading distances and 2. Computer vision PALs with a wider zone of clear vision at the monitor and in near vision but no clear distance vision. Twenty-three presbyopic participants wore each type of lens for two weeks in a double-masked four-week quasi-experimental procedure that included an adaptation phase (Weeks 1 and 2) and a test phase (Weeks 3 and 4). Questionnaires on visual and musculoskeletal conditions as well as preferences regarding the type of lenses were administered. After eight more weeks of free use of the spectacles, the preferences were assessed again. The ergonomic conditions were analysed from photographs. Head inclination when looking at the monitor was significantly lower by 2.3 degrees with the computer vision PALs than with the general purpose PALs. Vision at the monitor was judged significantly better with computer PALs, while distance vision was judged better with general purpose PALs; however, the reported advantage of computer vision PALs differed in extent between participants. Accordingly, 61 per cent of the participants preferred the computer vision PALs, when asked without information about lens design. After full information about lens characteristics and additional eight weeks of free spectacle use, 44 per cent preferred the computer vision PALs. On average, computer vision PALs were rated significantly better with respect to vision at the monitor during the experimental part of the study. In the final forced-choice ratings, approximately half of the participants preferred either the computer vision PAL or the general purpose PAL. Individual factors seem to play a role in this preference and in the rated advantage of computer vision PALs. © 2015 The Authors. Clinical and Experimental Optometry © 2015 Optometry Australia.

  1. DL_POLY_2.0: a general-purpose parallel molecular dynamics simulation package.

    PubMed

    Smith, W; Forester, T R

    1996-06-01

    DL_POLY_2.0 is a general-purpose parallel molecular dynamics simulation package developed at Daresbury Laboratory under the auspices of the Council for the Central Laboratory of the Research Councils. Written to support academic research, it has a wide range of applications and is designed to run on a wide range of computers: from single processor workstations to parallel supercomputers. Its structure, functionality, performance, and availability are described.

  2. 15KW General Purpose Power Conditioner (Frequency Changer). Inverter/Converter Integration.

    DTIC Science & Technology

    1980-10-01

    34AD-A097 165 GENERAL MOTORS CORP GOLETA CA DELCO ELECTRONICS DIV F/6 10/2 150K GENERAL PURPOSE POWER CONDITIONER (FREQUENCY CHANGER). INV--ETCIU...COMMAND B Fort Belvoir, Virginia Delco Electronics General Motors Corporation - Santa Barbara Operations DRI UTION STATEMENT A Santa Barbara...release; . Distribution Unlimited . DLCO ELECTRONICS DIVISION * SANTA EARUARA OPERATIONS * GENERAL MOTORS CORPORATION TABLE OF CONTENTS’. Section Page

  3. High-Precision Distribution of Highly Stable Optical Pulse Trains with 8.8 × 10−19 instability

    PubMed Central

    Ning, B.; Zhang, S. Y.; Hou, D.; Wu, J. T.; Li, Z. B.; Zhao, J. Y.

    2014-01-01

    The high-precision distribution of optical pulse trains via fibre links has had a considerable impact in many fields. In most published work, the accuracy is still fundamentally limited by unavoidable noise sources, such as thermal and shot noise from conventional photodiodes and thermal noise from mixers. Here, we demonstrate a new high-precision timing distribution system that uses a highly precise phase detector to obviously reduce the effect of these limitations. Instead of using photodiodes and microwave mixers, we use several fibre Sagnac-loop-based optical-microwave phase detectors (OM-PDs) to achieve optical-electrical conversion and phase measurements, thereby suppressing the sources of noise and achieving ultra-high accuracy. The results of a distribution experiment using a 10-km fibre link indicate that our system exhibits a residual instability of 2.0 × 10−15 at1 s and8.8 × 10−19 at 40,000 s and an integrated timing jitter as low as 3.8 fs in a bandwidth of 1 Hz to 100 kHz. This low instability and timing jitter make it possible for our system to be used in the distribution of optical-clock signals or in applications that require extremely accurate frequency/time synchronisation. PMID:24870442

  4. Superconducting Tunnel Junctions for High-Precision EUV Spectroscopy

    NASA Astrophysics Data System (ADS)

    Ponce, F.; Carpenter, M. H.; Cantor, R.; Friedrich, S.

    2016-08-01

    We have characterized the photon response of superconducting tunnel junctions in the extreme ultraviolet energy range below 100 eV with a pulsed 355 nm laser. The detectors are operated at rates up to 5000 counts/s, are very linear in energy and have an energy resolution between 0.9 and 2 eV. We observe multiple peaks that correspond to an integer number of photons with a Poissonian probability distribution and that can be used for high-accuracy energy calibration. The uncertainty of the centroid depends on the detector resolution and the counting statistics and can be as low as 1 meV for well-separated peaks with >10^5 counts. We discuss the precision of the peak centroid as a function of detector resolution and total number of counts and the accuracy of the energy calibration.

  5. Centroiding Experiment for Determining the Positions of Stars with High Precision

    NASA Astrophysics Data System (ADS)

    Yano, T.; Araki, H.; Hanada, H.; Tazawa, S.; Gouda, N.; Kobayashi, Y.; Yamada, Y.; Niwa, Y.

    2010-12-01

    We have experimented with the determination of the positions of star images on a detector with high precision such as 10 microarcseconds, required by a space astrometry satellite, JASMINE. In order to accomplish such a precision, we take the following two procedures. (1) We determine the positions of star images on the detector with the precision of about 0.01 pixel for one measurement, using an algorithm for estimating them from photon weighted means of the star images. (2) We determine the positions of star images with the precision of about 0.0001-0.00001 pixel, which corresponds to that of 10 microarcseconds, using a large amount of data over 10000 measurements, that is, the error of the positions decreases according to the amount of data. Here, we note that the procedure 2 is not accomplished when the systematic error in our data is not excluded adequately even if we use a large amount of data. We first show the method to determine the positions of star images on the detector using photon weighted means of star images. This algorithm, used in this experiment, is very useful because it is easy to calculate the photon weighted mean from the data. This is very important in treating a large amount of data. Furthermore, we need not assume the shape of the point spread function in deriving the centroid of star images. Second, we show the results in the laboratory experiment for precision of determining the positions of star images. We obtain that the precision of estimation of positions of star images on the detector is under a variance of 0.01 pixel for one measurement (procedure 1). We also obtain that the precision of the positions of star images becomes a variance of about 0.0001 pixel using about 10000 measurements (procedure 2).

  6. High-precision analysis of the solar twin HIP 100963

    NASA Astrophysics Data System (ADS)

    Yana Galarza, Jhon; Meléndez, Jorge; Ramírez, Ivan; Yong, David; Karakas, Amanda I.; Asplund, Martin; Liu, Fan

    2016-05-01

    Context. HIP 100963 was one of the first solar twins identified. Although some high-precision analyses are available, a comprehensive high-precision study of chemical elements from different nucleosynthetic sources is still lacking from which to obtain potential new insights on planets, stellar evolution, and Galactic chemical evolution (GCE). Aims: We analyze and investigate the origin of the abundance pattern of HIP 100963 in detail, in particular the pattern of the light element Li, the volatile and refractory elements, and heavy elements from the s- and r-processes. Methods: We used the HIRES spectrograph on the Keck I telescope to acquire high-resolution (R ≈ 70 000) spectra with a high signal-to-noise ratio (S/N ≈ 400-650 per pixel) of HIP 100963 and the Sun for a differential abundance analysis. We measured the equivalent widths (EWs) of iron lines to determine the stellar parameters by employing the differential spectroscopic equilibrium. We determined the composition of volatile, refractory, and neutron-capture elements through a differential abundance analysis with respect to the Sun. Results: The stellar parameters we found are Teff = 5818 ± 4 K, log g = 4.49 ± 0.01 dex, vt = 1.03 ± 0.01km s-1, and [Fe/H] = -0.003 ± 0.004 dex. These low errors allow us to compute a precise mass (1.03+0.02-0.01 M⊙) and age (2.0 ± 0.4 Gyr), obtained using Yonsei-Yale isochrones. Using our [Y/Mg] ratio, we have determined an age of 2.1 ± 0.4 Gyr, in agreement with the age computed using isochrones. Our isochronal age also agrees with the age determined from stellar activity (2.4 ± 0.3 Gyr). We study the abundance pattern with condensation temperature (Tcond) taking corrections by the GCE into account. We show that the enhancements of neutron-capture elements are explained by contributions from both the s- and r-process. The lithium abundance follows the tight Li-age correlation seen in other solar twins. Conclusions: We confirm that HIP 100963 is a solar twin

  7. Key techniques of the high precision gravity field system

    NASA Astrophysics Data System (ADS)

    Xu, Weimin; Chen, Shi; Lu, Hongyan; Shi, Lei

    2017-04-01

    Ground-based gravity time series provide a direct method to monitor all sources of mass changes from local to global scale. But the effectively infinite spatial sensitivity of gravity measurements make it difficult to isolate the signal of interest. The high precision gravity field system is an alternative approach of modeling mass changes under-ground. The field system, consists of absolute gravity, gravity and gravity gradient, GNSS, leveling and climate hydrology measurements, can improve the signal-to-noise ratio for many applications by removing contributions of unwanted signal from elevation changes, air pressure changes, local hydrology, and others. The networks of field system combination, such as field-profile in more than 100 kilometers, can be used in critical zone with high seismic risk for monitoring earth dynamics, volcanic and seismic phenomena. The system is constituted by 9 typical observation stations in 3*3 array (or 4 in 2*2 array) in 60 square meters field, each station is designed for integrated measurements, including absolute gravity, gravity gradient, elevation changes, air pressure and hydrology. Time-lapse gravity changes resulting from absolute gravimeter (FG5 or A10) with standard deviation less than 2 μGal, without the contributions of Earth tides, loading and polar motion. Additional measurements such as air pressure change, local hydrology and soil moisture are indispensable. The elevation changes resulting from GNSS (on the base station) and leveling (between stations) with precision less than 10 mm. The gravity gradient is the significant measurement for delimiting the location of the related mass changes underground the station, which is measured by Scintrex CG-5 gravimeters in different height (80cm in the test field), with precision less than 10 E. It is necessary to improve the precision of gravity gradient measurements by certain method in field experiment for the high precision measurement system. Acknowledgment: This

  8. High Precision Oxygen Measurements as a Tool for CCS Monitoring

    NASA Astrophysics Data System (ADS)

    Trugman, A. T.; Dvonch, C.; Clegg, S. M.; Rahn, T.

    2011-12-01

    CO2 emissions from below ground carbon storage reservoirs can be difficult to discriminate from CO2 produced via natural plant and microbial respiration. However, because respiration produces CO2 and consumes O2 in an approximately 1:1 ratio, it is possible to characterize leakage sources by measurement of simultaneous changes of both O2 and CO2. This approach is complicated by the fact that O2 comprises approximately 21% of the atmosphere, while CO2 is only present in the background atmosphere at ~400 parts per million, making it necessary to accurately measure changes in O2 concentration to six significant figures. Here we describe a portable high precision oxygen measurement system that employs a modified commercial fuel cell analyzer to quantify small changes in O2 concentration. High precision is achieved through precise control of flow and pressure, allowing near part per million precision of O2 and CO2 concentrations. This system has been incorporated into a mobile laboratory and has been deployed to the ZERT controlled release site in Bozeman, Montana and to a natural analog CO2 leak at Soda Springs, Idaho. Samples were collected at ground level, 1 meter, and 3 meters above the CO2 source and are displayed as the ratio of the O2 difference relative to a reference to the CO2 difference in concentration relative to the same reference (ΔO2/ΔCO2). It was observed that at wind speeds ≤ 2 m/s, the ΔO2/ΔCO2 anomaly decreased with height and was still significantly different from background at 3 m. With increasing wind speed, ΔO2/ΔCO2 anomalies decreased to background levels at 1 and 3 m but remained detectable at the ground surface. We will discuss attempts to quantify the CO2 release rate utilizing the measured ΔO2/ΔCO2 elevation profiles and will present complementary eddy covariance data for comparison.

  9. High-precision Velocimetry Reveals δ Cephei's Secret Companion

    NASA Astrophysics Data System (ADS)

    Anderson, Richard I.; Sahlmann, Johannes; Holl, Berry; Eyer, Laurent

    2015-08-01

    The search for extra-solar planets has driven tremendous improvements in the precision of radial velocities measured with high-resolution echelle spectrographs. However, relatively few studies have as of yet exploited the present-day extreme (m/s) instrumental precision to study Cepheid variable stars.We have been observing the prototype of classical Cepheids, δ Cephei, since September 2011 using the HERMES spectrograph mounted to the Mercator telescope located at the Roque de los Muchachos Observatory on the island of La Palma. Being one of the most-studied variable stars, we originally chose δ Cephei as a maximum-precision reference for other Cepheids in our sample. To our great surprise however, we discovered a clear orbital signature in the homogeneous HERMES data. Adding in radial velocity data from the literature, we then determined δ Cephei's orbit (cf. Anderson et al. 2015, arXiv:1503.04116). The high orbital eccentricity (e=0.647) leads to close pericenter passages (rmin ~ 9.5 RδCep) which suggest an intriguing past that requires further study, since Cepheids are well-known magnifying glasses for stellar evolution (Kippenhahn & Weigert 1994). We furthermore determined a new parallax to δ Cephei (using Hipparcos data) that is in tension with previous estimates and shows that the orbit will have to be accounted for when measuring δ Cephei's parallax with Gaia.While some of our HERMES data are as precise as 9 m/s, we found correlated excess residuals when removing the reference pulsation model and orbital motion from the HERMES radial velocity data, leaving an RMS of 47 m/s. These higher-than-expected residuals are reminiscent of the "period-jitter" or "flickering" observed in high-precision photometry of Cepheids obtained with the Kepler and MOST satellites. This reveals a fortuitous synergy between variable stars studies and the field of exoplanet research and opens the window for a better understanding of Cepheid pulsations via high-precision

  10. CUSB-II: a high precision electromagnetic spectrometer

    NASA Astrophysics Data System (ADS)

    Schamberger, R. D.; Heintz, U.; Lee-Franzini, J.; Lovelock, D. M. J.; Narain, M.; Willins, J.; Yanagisawa, C.; Tuts, P. M.; Franzini, P.; Kanekal, S.; Wu, Q. W.

    1991-11-01

    The design, construction and performance of a very compact precision electromagnetic spectrometer is described. The CUSB-II detector has been used to study ϒ spectroscopy, search for exotic particles and measure properties of the B and B ∗ mesons at the Cornell Electron Storage Ring.

  11. Decentralized high precision telemetry and telecommand system for sounding rockets

    NASA Astrophysics Data System (ADS)

    Heyer, Heinz-Volker; Schmitt, Günter; Pfeuffer, Horst; Voss, Bernhard

    2005-08-01

    TEXUS and MAXUS payloads are currently providing 12 bit analog channel accuracy for their data acquisition chains with different signal conditioning elements such as temperature measurement, strain gauge, pressure measurement channels, and general purpose amplifiers. Transient recording functions are rather seldom as all data is directly transmitted via PCM to the ground station. However, the user requirements are steadily increasing in terms of accuracy, data security, and high data throughput rate with an ever increasing number of telemetry channels. The newly developed Kayser-Threde telemetry and telecommand system CTS 3000 (Compact Telemetry System) fulfils these requirements by providing up to 16 bit accuracy for its analog channels with a sampling rate up to 2 kHz (at this accuracy), on-board transient memory to protect against data loss and provides an integrated telecommand decoder at the same time, reducing the necessary amount of equipment used for instrumentation. The equipment further reduces the necessary effort for refurbishment because of its internal self calibration over the full environment temperature range. On top of its IRIG PCM interface the system is equipped with a USB bus, a well-known and commonly used PC standard high performance interface. This interface is used for configuration, testing, and monitoring of the CTS 3000 providing a simple and easy to use user environment for the new equipment. The paper will introduce the new equipment and will show the application in the TEXUS/MAXUS project.

  12. High precision refractometry based on Fresnel diffraction from phase plates.

    PubMed

    Tavassoly, M Taghi; Naraghi, Roxana Rezvani; Nahal, Arashmid; Hassani, Khosrow

    2012-05-01

    When a transparent plane-parallel plate is illuminated at a boundary region by a monochromatic parallel beam of light, Fresnel diffraction occurs because of the abrupt change in phase imposed by the finite change in refractive index at the plate boundary. The visibility of the diffraction fringes varies periodically with changes in incident angle. The visibility period depends on the plate thickness and the refractive indices of the plate and the surrounding medium. Plotting the phase change versus incident angle or counting the visibility repetition in an incident-angle interval provides, for a given plate thickness, the refractive index of the plate very accurately. It is shown here that the refractive index of a plate can be determined without knowing the plate thickness. Therefore, the technique can be utilized for measuring plate thickness with high precision. In addition, by installing a plate with known refractive index in a rectangular cell filled with a liquid and following the described procedures, the refractive index of the liquid is obtained. The technique is applied to measure the refractive indices of a glass slide, distilled water, and ethanol. The potential and merits of the technique are also discussed.

  13. HIGH PRECISION ROVIBRATIONAL SPECTROSCOPY OF OH{sup +}

    SciTech Connect

    Markus, Charles R.; Hodges, James N.; Perry, Adam J.; Kocheril, G. Stephen; McCall, Benjamin J.; Müller, Holger S. P.

    2016-02-01

    The molecular ion OH{sup +} has long been known to be an important component of the interstellar medium. Its relative abundance can be used to indirectly measure cosmic ray ionization rates of hydrogen, and it is the first intermediate in the interstellar formation of water. To date, only a limited number of pure rotational transitions have been observed in the laboratory making it necessary to indirectly calculate rotational levels from high-precision rovibrational spectroscopy. We have remeasured 30 transitions in the fundamental band with MHz-level precision, in order to enable the prediction of a THz spectrum of OH{sup +}. The ions were produced in a water cooled discharge of O{sub 2}, H{sub 2}, and He, and the rovibrational transitions were measured with the technique Noise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy. These values have been included in a global fit of field free data to a {sup 3}Σ{sup −} linear molecule effective Hamiltonian to determine improved spectroscopic parameters which were used to predict the pure rotational transition frequencies.

  14. Laser interferometric high-precision angle monitor for JASMINE

    NASA Astrophysics Data System (ADS)

    Niwa, Yoshito; Arai, Koji; Sakagami, Masaaki; Gouda, Naoteru; Kobayashi, Yukiyasu; Yamada, Yoshiyuki; Yano, Taihei

    2006-06-01

    The JASMINE instrument uses a beam combiner to observe two different fields of view separated by 99.5 degrees simultaneously. This angle is so-called basic angle. The basic angle of JASMINE should be stabilized and fluctuations of the basic angle should be monitored with the accuracy of 10 microarcsec in root-mean-square over the satellite revolution period of 5 hours. For this purpose, a high-precision interferometric laser metrogy system is employed. One of the available techniques for measuring the fluctuations of the basic angle is a method known as the wave front sensing using a Fabry-Perot type laser interferometer. This technique is to detect fluctuations of the basic angle as displacement of optical axis in the Fabry-Perot cavity. One of the advantages of the technique is that the sensor is made to be sensitive only to the relative fluctuations of the basic angle which the JASMINE wants to know and to be insensitive to the common one; in order to make the optical axis displacement caused by relative motion enhanced the Fabry-Perot cavity is formed by two mirrors which have long radius of curvature. To verify the principle of this idea, the experiment was performed using a 0.1m-length Fabry-Perot cavity with the mirror curvature of 20m. The mirrors of the cavity were artificially actuated in either relative way or common way and the resultant outputs from the sensor were compared.

  15. High precision optomechanical assembly using threads as mechanical reference

    NASA Astrophysics Data System (ADS)

    Lamontagne, Frédéric; Desnoyers, Nichola; Bergeron, Guy; Cantin, Mario

    2016-09-01

    A convenient method to assemble optomechanical components is to use threaded interface. For example, lenses are often secured inside barrels using threaded rings. In other cases, multiple optical sub-assemblies such as lens barrels can be threaded to each other. Threads have the advantage to provide a simple assembly method, to be easy to manufacture, and to offer a compact mechanical design. On the other hand, threads are not considered to provide accurate centering between parts because of the assembly clearance between the inner and outer threads. For that reason, threads are often used in conjunction with precision cylindrical surfaces to limit the radial clearance between the parts to be centered. Therefore, tight manufacturing tolerances are needed on these pilot diameters, which affect the cost of the optical assembly. This paper presents a new optomechanical approach that uses threads as mechanical reference. This innovative method relies on geometric principles to auto-center parts to each other with a very low centering error that is usually less than 5 μm. The method allows to auto-center an optical group in a main barrel, to perform an axial adjustment of an optical group inside a main barrel, and to perform stacking of multiple barrels. In conjunction with the lens auto-centering method that also used threads as a mechanical reference, this novel solution opens new possibilities to realize a variety of different high precision optomechanical assemblies at lower cost.

  16. Highly precise and compact ultrahigh vacuum rotary feedthrough

    NASA Astrophysics Data System (ADS)

    Aiura, Y.; Kitano, K.

    2012-03-01

    The precision and rigidity of compact ultrahigh vacuum (UHV) rotary feedthroughs were substantially improved by preparing and installing an optimal crossed roller bearing with mounting holes. Since there are mounting holes on both the outer and inner races, the bearing can be mounted directly to rotary and stationary stages without any fixing plates and housing. As a result, it is possible to increase the thickness of the bearing or the size of the rolling elements in the bearing without increasing the distance between the rotating and fixing International Conflat flanges of the UHV rotary feedthrough. Larger rolling elements enhance the rigidity of the UHV rotary feedthrough. Moreover, owing to the structure having integrated inner and outer races and mounting holes, the performance is almost entirely unaffected by the installation of the bearing, allowing for a precise optical encoder to be installed in the compact UHV rotary feedthrough. Using position feedback via a worm gear system driven by a stepper motor and a precise rotary encoder, the actual angle of the compact UHV rotary feedthrough can be controlled with extremely high precision.

  17. Interferometric apparatus for ultra-high precision displacement measurement

    NASA Technical Reports Server (NTRS)

    Zhao, Feng (Inventor)

    2004-01-01

    A high-precision heterodyne interferometer measures relative displacement by creating a thermally-insensitive system generally not subject to polarization leakage. By using first and second light beams separated by a small frequency difference (.DELTA.f), beams of light at the first frequency (f.sub.0) are reflected by co-axial mirrors, the first mirror of which has a central aperture through which the light is transmitted to and reflected by the second mirror. Prior to detection, the light beams from the two mirrors are combined with light of the second and slightly different frequency. The combined light beams are separated according to the light from the mirrors. The change in phase (.DELTA..phi.) with respect to the two signals is proportional to the change in distance of Fiducial B by a factor of wavelength (.lambda.) divided by 4.pi. (.DELTA.L=.lambda..DELTA..phi.1/(4.pi.)). In a second embodiment, a polarizing beam splitting system can be used.

  18. High Precision U/Th Dating of First Polynesian Settlement

    PubMed Central

    Burley, David; Weisler, Marshall I.; Zhao, Jian-xin

    2012-01-01

    Previous studies document Nukuleka in the Kingdom of Tonga as a founder colony for first settlement of Polynesia by Lapita peoples. A limited number of radiocarbon dates are one line of evidence supporting this claim, but they cannot precisely establish when this event occurred, nor can they afford a detailed chronology for sequent occupation. High precision U/Th dates of Acropora coral files (abraders) from Nukuleka give unprecedented resolution, identifying the founder event by 2838±8 BP and documenting site development over the ensuing 250 years. The potential for dating error due to post depositional diagenetic alteration of ancient corals at Nukuleka also is addressed through sample preparation protocols and paired dates on spatially separated samples for individual specimens. Acropora coral files are widely distributed in Lapita sites across Oceania. U/Th dating of these artifacts provides unparalleled opportunities for greater precision and insight into the speed and timing of this final chapter in human settlement of the globe. PMID:23144962

  19. High-Precision Studies of Compact Variable Stars

    NASA Astrophysics Data System (ADS)

    Bloemen, Steven

    2014-10-01

    This book, which is a reworked and updated version of Steven Bloemen's original PhD thesis, reports on several high-precision studies of compact variable stars. Its strength lies in the large variety of observational, theoretical and instrumentation techniques that are presented and used and paves the way towards new and detailed asteroseismic applications of single and binary subdwarf stars. Close binary stars are studied using high cadence spectroscopic datasets collected with state of the art electron multiplying CCDs and analysed using Doppler tomography visualization techniques. The work touches upon instrumentation, presenting the calibration of a new fast, multi-colour camera installed at the Mercator Telescope on La Palma. The thesis also includes theoretical work on the computation of the temperature range in which stellar oscillations can be driven in subdwarf B-stars. Finally, the highlight of the thesis is the measurement of velocities of stars using only photometric data from NASA's Kepler satellite. Doppler beaming causes stars to appear slightly brighter when they move towards us in their orbits, and this subtle effect can be seen in Kepler's brightness measurements. The thesis presents the first validation of such velocity measurements using independent spectroscopic measurements. Since the detection and validation of this Doppler beaming effect, it has been used in tens of studies to detect and characterize binary star systems, which are key calibrators in stellar astronomy.

  20. High precision measurements of the free form mirror geometries

    NASA Astrophysics Data System (ADS)

    Dontsov, Denis; Rahneberg, Ilko; Pöschel, Wolfgang; Schott, Walter

    2017-06-01

    There are many established technologies for precise characterization of the mirror geometries available. The paper presents a high precision measuring setup based on a single beam homodyne laser interferometer. The single beam interferometer is moved by a linear stage between the reference and measuring surfaces and delivers the differences between them. The reference mirror defines an absolute accuracy of the method. This point based method allows a high spatial resolution of the mirror shape and is suitable for measurements of the free form mirror geometries as long as the radius of curvature does not exceed the maximal toleranced tilt. The measuring results have been obtained for optics with dimensions of up to 50 mm and have been verified both for plan mirrors and for mirrors with radii of curvature in the range between 6 m and 10 m. A repeatability of the measuring results in sub-nanometer range can be shown. Especially for mirrors with a very big radius of curvature the knowledge of the exact position of the each measuring point on the surface is important for minimizing the errors of the mathematical fitting algorithms. Therefore a triple beam interferometer has been used for measurements of the stage position. The tight synchronization between all interferometer channels of 0.1 ns allows very fast "on-the-fly" scans of the surface.

  1. HST high-precision proper motions of globular clusters

    NASA Astrophysics Data System (ADS)

    Bellini, Andrea; Anderson, Jay; van der marel, roeland p.; piotto, gianpaolo; Watkins, Laura l.; Vesperini, Enrico; Milone, Antonino; Bedin, Luigi R.

    2015-08-01

    The stable environment of space makes HST an excellent astrometric tool. Its diffraction-limited resolution allows it to distinguish and measure positions and fluxes for stars all the way to the center of most globular clusters. There are now many clusters that have observations in the archive that span 13 years or more, and more observations are being taken all the time. We constructed high-precision proper-motion catalogs for over 20 clusters for which there exist two or more well-separated epochs in the archive, and we are extending the list to over 60 objects, thanks to the new observations taken within the ``HST UV Legacy Survey of Galactic Globular Clusters’’ treasury program. Each catalog contains astrometry and photometry for thousands of stars within two arcmin of the center. The catalogs are focused on the many stars within a few magnitudes of the turnoff and have typical proper-motion errors of 0.1 mas/yr, which translates to 2 km/s for the typical cluster. We are using proper motions to directly measure the clusters' anisotropy, equipartition and rotation on the plane of the sky, as well as to study internal kinematics of the different subpopulations and to probe the presence of an IMBH in their core.

  2. High-Precision Single Photon Timing of Pulsars

    NASA Astrophysics Data System (ADS)

    Ransom, Scott M.; Ray, Paul S.; Kerr, Matthew

    2017-08-01

    We have developed a likelihood-based technique, implemented through Markov Chain Monte Carlo, that enables high-precision pulsar timing using individual x-rays or gamma-rays. Our current implementaion leverages the new timing software PINT for timing model details and provides several significant advantages over earlier, more traditional, timing techniques. Our method does not require the integration of an average pulse profile from which a "time of arrival" is computed. This is crucial when the photon count rates are too low to produce a good pulse profile on the timescales of other important timing properties of the system (such as an orbital period of a binary pulsar). Arbitrary weights can be applied to each photon to indicate, for instance, the probability that each event might be a background photon. Many other improvements are being developed, such as simultaneously determining the timing solution and a template profile and parallel calculation of the likelihoods. We have successfully applied the technique to a variety of Fermi pulsars and will be using it extensively for timing analyses during the NICER mission.

  3. Measuring Crustal Deformation in Europe by High Precision Geodetic VLBI

    NASA Astrophysics Data System (ADS)

    Campbell, J.; Nothnagel, A.; Vennebusch, M.

    2002-06-01

    At the western tip of the Eurasian plate, the European continent is besieged by thrusting and receding neighbour plates causing deformations and ruptures of the Earth's crust evidenced by earthquakes and volcanic outbursts. Measuring the extent and progress of crustal deformation has become one of the primary tasks of geodesists and geophysicists. Realizing that Europe enjoys one of the densest networks of radio telescopes especially equipped for high precision, geodetic VLBI has provided the incentive to organise a campaign of regular geodetic VLBI observations in the European network of fixed radio telescopes. The measurements have been carried out since the late eighties at an average rate of six sessions per year. From these data, site coordinates, baseline length changes and station velocity vectors have been derived with steadily increasing accuracy. The overall picture of the observed present-day site motions emulates quite well the pattern of tectonic motions inferred from the geotectonic setting of central Europe and the western Mediterranean. Interesting details are emerging for horizontal motions of the three stations in Italy, which are strongly affected by the complex interactions between the different tectonic regimes in this area. The accuracy of the vertical components is also improving with increasing length of the observational record, allowing to detect significant trends among the relative vertical motions of the sites. The geodetic VLBI network operations have received supportive funding by the European Union under the 2nd and 4th Framework Programmes.

  4. A simplified, general-purpose deep-space ranging correlator design

    NASA Technical Reports Server (NTRS)

    Tausworthe, R. C.; Smith, J. R.

    1988-01-01

    A much-simplified, yet more general-purpose multi-channel deep-space ranging system correlator design that was used in past JPL spacecraft ranging systems is described. The method applies to detection of both single-component and multiple-component ranging codes, in either sequential (mu) or composite (pi) transmitted forms, and using either pseudonoise or square-wave components. Using this design, the Phobos Probe ranging system correlator computational complexity was reduced by over three orders of magnitude in multiply-and-add circuits and 45,000 bits of accumulator storage.

  5. Generalized Fluid System Simulation Program (GFSSP) Version 6 - General Purpose Thermo-Fluid Network Analysis Software

    NASA Technical Reports Server (NTRS)

    Majumdar, Alok; Leclair, Andre; Moore, Ric; Schallhorn, Paul

    2011-01-01

    GFSSP stands for Generalized Fluid System Simulation Program. It is a general-purpose computer program to compute pressure, temperature and flow distribution in a flow network. GFSSP calculates pressure, temperature, and concentrations at nodes and calculates flow rates through branches. It was primarily developed to analyze Internal Flow Analysis of a Turbopump Transient Flow Analysis of a Propulsion System. GFSSP development started in 1994 with an objective to provide a generalized and easy to use flow analysis tool for thermo-fluid systems.

  6. Real-time radar signal processing using GPGPU (general-purpose graphic processing unit)

    NASA Astrophysics Data System (ADS)

    Kong, Fanxing; Zhang, Yan Rockee; Cai, Jingxiao; Palmer, Robert D.

    2016-05-01

    This study introduces a practical approach to develop real-time signal processing chain for general phased array radar on NVIDIA GPUs(Graphical Processing Units) using CUDA (Compute Unified Device Architecture) libraries such as cuBlas and cuFFT, which are adopted from open source libraries and optimized for the NVIDIA GPUs. The processed results are rigorously verified against those from the CPUs. Performance benchmarked in computation time with various input data cube sizes are compared across GPUs and CPUs. Through the analysis, it will be demonstrated that GPGPUs (General Purpose GPU) real-time processing of the array radar data is possible with relatively low-cost commercial GPUs.

  7. General purpose simulation system of the data management system for space shuttle mission 18

    NASA Technical Reports Server (NTRS)

    Bengtson, N. M.; Mellichamp, J. M.; Crenshaw, J.

    1975-01-01

    The simulation program of the science and engineering data management system for the space shuttle is presented. The programming language used was General Purpose Simulation System V (OS). The data flow was modeled from its origin at the experiments or subsystems to transmission from the space shuttle. Mission 18 was the particular flight chosen for simulation. First, the general structure of the program is presented and the trade studies which were performed are identified. Inputs required to make runs are discussed followed by identification of the output statistics. Some areas for model modifications are pointed out. A detailed model configuration, program listing and results are included.

  8. General purpose pulse shape analysis for fast scintillators implemented in digital readout electronics

    NASA Astrophysics Data System (ADS)

    Asztalos, Stephen J.; Hennig, Wolfgang; Warburton, William K.

    2016-01-01

    Pulse shape discrimination applied to certain fast scintillators is usually performed offline. In sufficiently high-event rate environments data transfer and storage become problematic, which suggests a different analysis approach. In response, we have implemented a general purpose pulse shape analysis algorithm in the XIA Pixie-500 and Pixie-500 Express digital spectrometers. In this implementation waveforms are processed in real time, reducing the pulse characteristics to a few pulse shape analysis parameters and eliminating time-consuming waveform transfer and storage. We discuss implementation of these features, their advantages, necessary trade-offs and performance. Measurements from bench top and experimental setups using fast scintillators and XIA processors are presented.

  9. A general purpose nonlinear rigid body mass finite element for application to rotary wing dynamics

    NASA Technical Reports Server (NTRS)

    Hamilton, B. K.; Straub, F. K.; Ruzicka, G. C.

    1991-01-01

    The Second Generation Comprehensive Helicopter Analysis System employs the present formulation of the general-purpose nonlinear rigid body mass finite element, which represents the hub masses, blade tip masses, and pendulum vibration absorbers. The rigid body mass element has six degrees of freedom, and accounts for gravitational as well as dynamic effects. A consequence of deriving the element's equations from various physical principles is that, prior to the transformation which couples the rigid body mass element to the rotor blade finite element, the forces obtained for each element are fundamentally different; this is true notwithstanding the degrees-of-freedom of each element are parameterized using the same coordinates.

  10. Software design of a general purpose data acquisition and control executive

    SciTech Connect

    Labiak, W.G.; Minor, E.G.

    1981-05-22

    The software design of an executive which performs general purpose data acquisition, monitoring, and control is presented. The executive runs on a memory-based mini or micro-computer and communicates with a disk-based computer where data analysis and display are done. The executive design stresses reliability and versatility, and has yielded software which can provide control and monitoring for widely different hardware systems. Applications of this software on two major fusion energy experiments at Lawrence Livermore National Laboratory will be described.

  11. General-purpose heat source project and space nuclear safety fuels program. Progress report, February 1980

    SciTech Connect

    Maraman, W.J.

    1980-05-01

    This formal monthly report covers the studies related to the use of /sup 238/PuO/sub 2/ in radioisotopic power systems carried out for the Advanced Nuclear Systems and Projects Division of the Los Alamos Scientific Laboratory. The two programs involved are: General-Purpose Heat Source Development and Space Nuclear Safety and Fuels. Most of the studies discussed here are of a continuing nature. Results and conclusions described may change as the work continues. Published reference to the results cited in this report should not be made without the explicit permission of the person in charge of the work.

  12. SIG: a general-purpose signal processing program. User's manual. Revision 1

    SciTech Connect

    Lager, D.; Azevedo, S.

    1985-05-09

    SIG is a general-purpose signal processing, analysis, and display program. Its main purpose is to perform manipulations on time-domain and frequenccy-domain signals. The manual contains a complete description of the SIG program from the user's stand-point. A brief exercise in using SIG is shown. Complete descriptions are given of each command in the SIG core. General information about the SIG structure, command processor, and graphics options are provided. An example usage of SIG for solving a problem is developed, and error message formats are briefly discussed. (LEW)

  13. A high-precision earth sensor with three separated FOVs for aircraft application

    NASA Astrophysics Data System (ADS)

    Wang, Hongjian; Xing, Fei; Fan, Peirong; Wang, Chong; You, Zheng

    2013-08-01

    The earth sensors are currently used in spacecrafts. Most of them with a single field of view (FOV) for earth observation are not applied to aircrafts in the atmosphere. For the use of the aircraft at 70 ~ 100km in the atmosphere, this paper proposes a separate triple-FOV earth sensor based on infrared detectors. By sensing the earth-horizon, the triple-FOV earth sensor obtains the geocentric vector, and calculates the altitude of the aircraft at the same time. The earth sensor uses three pieces of infrared detectors at 14 ~ 16μm. To sense the infrared light could ensure that the earth sensor does the same operation at night and day regardless of the weather and the light impact of the sun and the moon. The optical axes of the three fields of view are positioned at 120° from each other in the horizontal plane, and the angle between the optical axes and the vertical direction is 82.86°. Considering the model of the surface of the earth's atmosphere, the earth's radius and so on, the mathematical model of the triple-FOV earth sensor is established. From 70km to 100km, the result of simulation shows that the altitude measurement accuracy is better than 100m and the angle measurement error is 3.8". The earth sensor can provide high-precision position information, and make data fusion with additional sensors to achieve autonomous navigation of aircrafts.

  14. High Precision Bright-Star Astrometry with the USNO Astrometric CMOS Hybrid Camera System

    NASA Astrophysics Data System (ADS)

    Secrest, Nathan; Dudik, Rachel; Berghea, Ciprian T.; Hennessy, Greg; Dorland, Bryan

    2015-05-01

    While GAIA will provide excellent positional measurements of hundreds of millions of stars between 5 < mag < 20, an ongoing challenge in the field of high-precision differential astrometry is the positional accuracy of very bright stars (mag < 5), due to the enormous dynamic range between bright stars of interest, such as those in the Hipparcos catalog, and their background field stars, which are especially important for differential astrometry. Over the past few years, we have been testing the USNO Astrometric CMOS Hybrid Camera System (UAHC), which utilizes an H4RG-10 detector in windowing mode, as a possible solution to the NOFS USNO Bright Star Astrometric Database (UBAD). In this work, we discuss the results of an astrometric analysis of single-epoch Hipparcos data taken with the UAHC from the 1.55m Kaj Strand Astrometric Reflector at NOFS from June 27-30, 2014. We discuss the calibration of this data, as well as an astrometric analysis pipeline we developed that will enable multi-epoch differential and absolute astrometry with the UAHC. We find that while the overall differential astrometric stability of data taken with the UAHC is good (5-10 mas single-measurement precision) and comparable to other ground-based astrometric camera systems, bright stars in the detector window suffer from several systematic effects, such as insufficient window geometry and centroiding failures due to read-out artifacts - both of which can be significantly improved with modifications to the electronics, read-out speed and microcode.

  15. High-Precision Isotope Ratio Measurements of Sub-Picogram Actinide Samples

    NASA Astrophysics Data System (ADS)

    Pollington, A. D.; Kinman, W.

    2016-12-01

    One of the most exciting trends in analytical geochemistry over the past decade is the push towards smaller and smaller sample sizes while simultaneously achieving high precision isotope ratio measurements. This trend has been driven by advances in clean chemistry protocols, and by significant breakthroughs in mass spectrometer ionization efficiency and detector quality (stability and noise for low signals). In this presentation I will focus on new techniques currently being developed at Los Alamos National Laboratory for the characterization of ultra-small samples (pg, fg, ag), with particular focus on actinide measurements by MC-ICP-MS. Analyses of U, Pu, Th and Am are routinely carried out in our facility using multi-ion counting techniques. I will describe some of the challenges associated with using exclusively ion counting methods (e.g., stability, detector cross calibration, etc.), and how we work to mitigate them. While the focus of much of the work currently being carried out is in the broad field of nuclear forensics and safeguards, the techniques that are being developed are directly applicable to many geologic questions that require analyses of small samples of U and Th, for example. In addition to the description of the technique development, I will present case studies demonstrating the precision and accuracy of the method as applied to real-world samples.

  16. A high precision calorimeter for the SOX experiment

    NASA Astrophysics Data System (ADS)

    Papp, L.; Agostini, M.; Altenmüller, K.; Appel, S.; Caminata, A.; Cereseto, R.; Di Noto, L.; Farinon, S.; Musenich, R.; Neumair, B.; Oberauer, L.; Pallavicini, M.; Schönert, S.; Testera, G.; Zavatarelli, S.

    2016-07-01

    The SOX (Short distance neutrino Oscillations with BoreXino) experiment is being built to discover or reject eV-scale sterile neutrinos by observing short baseline oscillations of active-to-sterile neutrinos [1]. For this purpose, a 100 kCi 144Ce-144Pr antineutrino generator (CeSOX) will be placed under the BOREXINO detector at the Laboratori Nazionali del Gran Sasso. Thanks to its large size and very low background, BOREXINO is an ideal detector to discover or reject eV-scale sterile neutrinos. To reach the maximal sensitivity, we aim at determining the neutrino flux emitted by the antineutrino generator with a < 1 % accuracy. With this goal, TU München and INFN Genova are developing a vacuum calorimeter, which is designed to measure the source-generated heat with high accuracy.

  17. Comparison of a neonatal versus general-purpose amino acid formulation in preterm neonates.

    PubMed

    Adamkin, D D; Radmacher, P; Rosen, P

    1995-01-01

    Twenty preterm infants were randomly assigned to receive either a general-purpose intravenous amino acid solution or a neonatal formula at 1.5 gm/kg/day with 50 nonprotein energy calories for 1 week. Both groups demonstrated similar rates of weight gain and similar liver function test results, but comparison of changes from baseline amino acid values disclosed significant intergroup differences for levels of plasma glycine, taurine, valine, and methionine after 7 days of infusion. Comparison of plasma aminograms of study patients with those of normally growing, enterally fed preterm infants showed that infants who received the neonatal solution had similar amino acid profiles, with the exception of low plasma concentrations of tyrosine and elevated concentrations of threonine. The general-purpose solution, as compared with findings in historic enteral controls, produced low plasma valine, tyrosine, and taurine levels, and elevated levels of glycine and methionine. Advantages with the neonatal amino acid solution include reductions in plasma glycine and methionine levels, plus the provision of taurine. Providing tyrosine remains a problem.

  18. Neural Networks for Computer Vision: A Framework for Specifications of a General Purpose Vision System

    NASA Astrophysics Data System (ADS)

    Skrzypek, Josef; Mesrobian, Edmond; Gungner, David J.

    1989-03-01

    The development of autonomous land vehicles (ALV) capable of operating in an unconstrained environment has proven to be a formidable research effort. The unpredictability of events in such an environment calls for the design of a robust perceptual system, an impossible task requiring the programming of a system bases on the expectation of future, unconstrained events. Hence, the need for a "general purpose" machine vision system that is capable of perceiving and understanding images in an unconstrained environment in real-time. The research undertaken at the UCLA Machine Perception Laboratory addresses this need by focusing on two specific issues: 1) the long term goals for machine vision research as a joint effort between the neurosciences and computer science; and 2) a framework for evaluating progress in machine vision. In the past, vision research has been carried out independently within different fields including neurosciences, psychology, computer science, and electrical engineering. Our interdisciplinary approach to vision research is based on the rigorous combination of computational neuroscience, as derived from neurophysiology and neuropsychology, with computer science and electrical engineering. The primary motivation behind our approach is that the human visual system is the only existing example of a "general purpose" vision system and using a neurally based computing substrate, it can complete all necessary visual tasks in real-time.

  19. General-purpose and dedicated regimes in the use of telescopes

    NASA Astrophysics Data System (ADS)

    Lamy, Jérôme; Davoust, Emmanuel

    2009-11-01

    We propose a socio-historical framework for better understanding the evolution in the use of telescopes. We define two regimes of use: a general-purpose (or survey) one, where the telescope governs research, and a dedicated one, in which the telescope is tailored to a specific project which includes a network of other tools. This conceptual framework is first applied to the history of the 80-cm reflector at the Toulouse Observatory, which was initially anchored in a general-purpose regime linked to astrometry. After a transition in the 1930s, it was integrated into a dedicated regime centered on astrophysics. This evolution is compared to that of a very similar instrument, the 80-cm reflector at the Marseille Observatory, which was converted to a dedicated regime with the Fabry-Perot interferometer around 1910, and, after a period of idleness, was again used in the survey mode after WWII. To further validate our new concept, we apply it to the telescopes at the Washburn Observatory, the Dominion Astrophysical Observatory and the Meudon Observatory. The uses of the different telescopes illustrate various combinations of the two regimes, which can be successive, simultaneous or alternating. This conceptual framework is likely to be applicable to other fields of pure and applied science.

  20. General Purpose Data-Driven Online System Health Monitoring with Applications to Space Operations

    NASA Technical Reports Server (NTRS)

    Iverson, David L.; Spirkovska, Lilly; Schwabacher, Mark

    2010-01-01

    Modern space transportation and ground support system designs are becoming increasingly sophisticated and complex. Determining the health state of these systems using traditional parameter limit checking, or model-based or rule-based methods is becoming more difficult as the number of sensors and component interactions grows. Data-driven monitoring techniques have been developed to address these issues by analyzing system operations data to automatically characterize normal system behavior. System health can be monitored by comparing real-time operating data with these nominal characterizations, providing detection of anomalous data signatures indicative of system faults, failures, or precursors of significant failures. The Inductive Monitoring System (IMS) is a general purpose, data-driven system health monitoring software tool that has been successfully applied to several aerospace applications and is under evaluation for anomaly detection in vehicle and ground equipment for next generation launch systems. After an introduction to IMS application development, we discuss these NASA online monitoring applications, including the integration of IMS with complementary model-based and rule-based methods. Although the examples presented in this paper are from space operations applications, IMS is a general-purpose health-monitoring tool that is also applicable to power generation and transmission system monitoring.

  1. High-precision photometry of WASP-12 b transits

    NASA Astrophysics Data System (ADS)

    Maciejewski, G.; Errmann, R.; Raetz, St.; Seeliger, M.; Spaleniak, I.; Neuhäuser, R.

    2011-04-01

    Aims: The transiting extrasolar planet WASP-12 b was found to be one of the most intensely irradiated exoplanets. It is unexpectedly bloated and is losing mass that may accrete into the host star. Our aim was to refine the parameters of this intriguing system and search for signs of transit timing variations. Methods: We gathered high-precision light curves for two transits of WASP-12 b. Assuming various limb-darkening laws, we generated best-fitting models and redetermined the parameters of the system. Error estimates were derived by the prayer-bead method and Monte Carlo simulations. Results: System parameters obtained by us are found to agree with previous studies within one sigma. Use of the non-linear limb-darkening laws results in the best-fitting models. With two new mid-transit times, the ephemeris was refined to BJDTDB = (2 454 508.97682 ± 0.00020) + (1.09142245 ± 0.00000033)E. Interestingly, indications of transit timing variation are detected at the level of 3.4 sigma. This signal can be induced by an additional planet in the system. Simplified numerical simulations show that a perturber could be a terrestrial-type planet if both planets are in a low-order orbital resonance. However, we emphasise that further observations are needed to confirm variation and to constrain properties of the perturber. Based on observations collected at the Centro Astronómico Hispano Alemán (CAHA), operated jointly by the Max-Planck Institut für Astronomie and the Instituto de Astrofisica de Andalucia (CSIC).Photometric data are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/528/A65

  2. Developing Performance Estimates for High Precision Astrometry with TMT

    NASA Astrophysics Data System (ADS)

    Schoeck, Matthias; Do, Tuan; Ellerbroek, Brent; Herriot, Glen; Meyer, Leo; Suzuki, Ryuji; Wang, Lianqi; Yelda, Sylvana

    2013-12-01

    Adaptive optics on Extremely Large Telescopes will open up many new science cases or expand existing science into regimes unattainable with the current generation of telescopes. One example of this is high-precision astrometry, which has requirements in the range from 10 to 50 micro-arc-seconds for some instruments and science cases. Achieving these requirements imposes stringent constraints on the design of the entire observatory, but also on the calibration procedures, observing sequences and the data analysis techniques. This paper summarizes our efforts to develop a top down astrometry error budget for TMT. It is predominantly developed for the first-light AO system, NFIRAOS, and the IRIS instrument, but many terms are applicable to other configurations as well. Astrometry error sources are divided into 5 categories: Reference source and catalog errors, atmospheric refraction correction errors, other residual atmospheric effects, opto-mechanical errors and focal plane measurement errors. Results are developed in parametric form whenever possible. However, almost every error term in the error budget depends on the details of the astrometry observations, such as whether absolute or differential astrometry is the goal, whether one observes a sparse or crowded field, what the time scales of interest are, etc. Thus, it is not possible to develop a single error budget that applies to all science cases and separate budgets are developed and detailed for key astrometric observations. Our error budget is consistent with the requirements for differential astrometry of tens of micro-arc-seconds for certain science cases. While no show stoppers have been found, the work has resulted in several modifications to the NFIRAOS optical surface specifications and reference source design that will help improve the achievable astrometry precision even further.

  3. Highly precise and robust packaging of optical components

    NASA Astrophysics Data System (ADS)

    Leers, Michael; Winzen, Matthias; Liermann, Erik; Faidel, Heinrich; Westphalen, Thomas; Miesner, Jörn; Luttmann, Jörg; Hoffmann, Dieter

    2012-03-01

    In this paper we present the development of a compact, thermo-optically stable and vibration and mechanical shock resistant mounting technique by soldering of optical components. Based on this technique a new generation of laser sources for aerospace applications is designed. In these laser systems solder technique replaces the glued and bolted connections between optical component, mount and base plate. Alignment precision in the arc second range and realization of long term stability of every single part in the laser system is the main challenge. At the Fraunhofer Institute for Laser Technology ILT a soldering and mounting technique has been developed for high precision packaging. The specified environmental boundary conditions (e.g. a temperature range of -40 °C to +50 °C) and the required degrees of freedom for the alignment of the components have been taken into account for this technique. In general the advantage of soldering compared to gluing is that there is no outgassing. In addition no flux is needed in our special process. The joining process allows multiple alignments by remelting the solder. The alignment is done in the liquid phase of the solder by a 6 axis manipulator with a step width in the nm range and a tilt in the arc second range. In a next step the optical components have to pass the environmental tests. The total misalignment of the component to its adapter after the thermal cycle tests is less than 10 arc seconds. The mechanical stability tests regarding shear, vibration and shock behavior are well within the requirements.

  4. Injector linac stability requirements for high precision experiments at MESA

    NASA Astrophysics Data System (ADS)

    Hug, F.; Heine, R.

    2017-07-01

    MESA is a recirculating superconducting accelerator under construction at Johannes Gutenberg-Universität Mainz. It will be used for high precision particle physics experiments in two different operation modes: external beam (EB) mode and energy recovery (ERL) mode. The operating beam current and energy in EB mode is 0.15 mA with polarized electrons at 155 MeV. In ERL mode an unpolarized beam of 1 mA at 105 MeV will be available. In a later construction stage of MESA the beam current in ERL-mode shall be upgraded to 10 mA. In order to achieve high beam stability and low energy spread in recirculating operation for external beam the acceleration in the main linac sections will be done on a certain phase with respect to the maximum of the accelerating field (off crest) while the return arcs provide longitudinal dispersion. On specific longitudinal working points this can result in a setting where any RF phase or magnitude jitters from main linac do not contribute to the resulting energy spread of the final beam at all. Then the resulting energy spread of the beam at the experiment is mostly determined by the beam properties provided by the injector linac. On the other hand the acceleration in ERL operation mode most likely needs to be done on crest of the accelerating field aiming for the highest efficiency in the energy recovering process albeit we are currently investigating different recirculation schemes for the ERL mode as well. Using on crest acceleration the achievable energy spread is determined by the longitudinal phase space properties behind the injector linac again but mostly by the bunch length of the beam injected to the main linac. Within this contribution we will investigate the requirements on the stability of the MESA injector linac MAMBO for achieving the experimental goals under both operating conditions.

  5. The new versatile general purpose surface-muon instrument (GPS) based on silicon photomultipliers for μSR measurements on a continuous-wave beam

    NASA Astrophysics Data System (ADS)

    Amato, A.; Luetkens, H.; Sedlak, K.; Stoykov, A.; Scheuermann, R.; Elender, M.; Raselli, A.; Graf, D.

    2017-09-01

    We report on the design and commissioning of a new spectrometer for muon-spin relaxation/rotation studies installed at the Swiss Muon Source (SμS) of the Paul Scherrer Institute (PSI, Switzerland). This new instrument is essentially a new design and replaces the old general-purpose surface-muon (GPS) instrument that has been for long the workhorse of the μSR user facility at PSI. By making use of muon and positron detectors made of plastic scintillators read out by silicon photomultipliers, a time resolution of the complete instrument of about 160 ps (standard deviation) could be achieved. In addition, the absence of light guides, which are needed in traditionally built μSR instrument to deliver the scintillation light to photomultiplier tubes located outside magnetic fields applied, allowed us to design a compact instrument with a detector set covering an increased solid angle compared with the old GPS.

  6. Application of a Computerized General Purpose Information Management System (SELGEM) (SELf-GEnerating Master) to Medically Important Arthropods (Diptera: Culicidae).

    DTIC Science & Technology

    1982-07-01

    GENERAL PURPOSE INFORMATION MANAGEMENT SYSTEM (SELGEM) TO MEDICALLY 0 IMPORTANT ARTHROPODS (DIPTERA: CULICIDAE) oAnnual Report Terry L. Erwin July...APPLICATION OF A COMPUTERIZED GENERAL PURPOSE Annual Report INFORMATION MANAGEMENT SYSTEM (SELGEM) TO July 1981 to June 1982 MEDICALLY IMPORTANT ARTHROPODS

  7. High Precision Material Study at Near Millimeter Wavelengths.

    DTIC Science & Technology

    1983-08-30

    Laser, Rexolite, TPX , Dynasil 4000. LQj .~4 20.1 ABSR*ACT ’Cath- do -- e8e11110 if nmwe*my selIdenti by block n"Whe") ’-2 Various quasi-optical...pyroelectric detectors (Laser Precision Rkp-545): L L, and L TPx lens; BS1, wire-mesh beam splitter; BS, mylar-film beam splitter; DPC, double-prism coupler...focused at the entrance to the guide with a waist radius of approximately 0.6435a, where a is the radius of the guide. A lens made from TPX plastic was

  8. Photonic systems for high precision radial velocity measurements

    NASA Astrophysics Data System (ADS)

    Halverson, Samuel P.

    The discovery of Earth-like exoplanets has profound implications for our understanding of the origins and diversity of life in our universe. As such, developing new and improved Doppler radial velocity (RV) spectrometers capable of discovering and characterizing these planets is a high priority in the astronomical community. However, detection of true Earth-analogs remains beyond the technical reach of current Doppler RV instruments. This thesis discusses a number of technological developments designed specifically to overcome classical instrumental limitations of high precision Doppler RV measurements. These technologies are essential components of next generation instruments that aim to achieve the RV precision necessary to detect low-mass planets. This instrumentation research is driven by the development of the Habitable-zone Planet Finder (HPF), a near-infrared (NIR) Doppler spectrograph currently under development at Penn State that will detect terrestrial-mass planets orbiting nearby M-dwarfs. Furthermore, many technologies discussed will also be applied to the NASA-NSF Extreme Precision Doppler Spectrometer concept NEID, a Doppler RV instrument for the 3.5 meter WIYN telescope, slated for delivery in 2019. NEID is an ultra-stable, high resolution optical spectrometer also under development at Penn State. This thesis describes new specialized optical fiber delivery systems, designed to significantly improve instrument illumination stability, modal noise suppression systems, which suppress mode interference in optical fibers and allow spectrometers to fully realize the exquisite precision of modern wavelength calibration sources, and new photonic calibration sources, which show significant promise as potential Doppler wavelength references. These technologies represent important steps in enabling next generation instruments to reach precisions sufficient to detect terrestrial-mass planets orbiting in the Habitable-zones of nearby stars. Improving measurement

  9. Developing and implementing a high precision setup system

    NASA Astrophysics Data System (ADS)

    Peng, Lee-Cheng

    The demand for high-precision radiotherapy (HPRT) was first implemented in stereotactic radiosurgery using a rigid, invasive stereotactic head frame. Fractionated stereotactic radiotherapy (SRT) with a frameless device was developed along a growing interest in sophisticated treatment with a tight margin and high-dose gradient. This dissertation establishes the complete management for HPRT in the process of frameless SRT, including image-guided localization, immobilization, and dose evaluation. The most ideal and precise positioning system can allow for ease of relocation, real-time patient movement assessment, high accuracy, and no additional dose in daily use. A new image-guided stereotactic positioning system (IGSPS), the Align RT3C 3D surface camera system (ART, VisionRT), which combines 3D surface images and uses a real-time tracking technique, was developed to ensure accurate positioning at the first place. The uncertainties of current optical tracking system, which causes patient discomfort due to additional bite plates using the dental impression technique and external markers, are found. The accuracy and feasibility of ART is validated by comparisons with the optical tracking and cone-beam computed tomography (CBCT) systems. Additionally, an effective daily quality assurance (QA) program for the linear accelerator and multiple IGSPSs is the most important factor to ensure system performance in daily use. Currently, systematic errors from the phantom variety and long measurement time caused by switching phantoms were discovered. We investigated the use of a commercially available daily QA device to improve the efficiency and thoroughness. Reasonable action level has been established by considering dosimetric relevance and clinic flow. As for intricate treatments, the effect of dose deviation caused by setup errors remains uncertain on tumor coverage and toxicity on OARs. The lack of adequate dosimetric simulations based on the true treatment coordinates from

  10. Conceptual Trade Study of General Purpose Heat Source Powered Stirling Converter Configurations

    NASA Technical Reports Server (NTRS)

    Turpin, J. B.

    2007-01-01

    This Technical Manual describes a parametric study of general purpose heat source (GPHS) powered Stirling converter configurations. This study was performed in support of MSFC s efforts to establish the capability to perform non-nuclear system level testing and integration of radioisotope power systems. Six different GPHS stack configurations at a total of three different power levels (80, 250, and 500 W(sub e) were analyzed. The thermal profiles of the integrated GPHS modules (for each configuration) were calculated to determine maximum temperatures for comparison to allowable material limits. Temperature profiles for off-nominal power conditions were also assessed in order to better understand how power demands from the Stirling engine impact the performance of a given configuration.

  11. Literature Review: Weldability of Iridium DOP-26 Alloy for General Purpose Heat Source

    SciTech Connect

    Burgardt, Paul; Pierce, Stanley W.

    2016-10-19

    The basic purpose of this paper is to provide a literature review relative to fabrication of the General Purpose Heat Source (GPHS) that is used to provide electrical power for deep space missions of NASA. The particular fabrication operation to be addressed here is arc welding of the GPHS encapsulation. A considerable effort was made to optimize the fabrication of the fuel pellets and of other elements of the encapsulation; that work will not be directly addressed in this paper. This report consists of three basic sections: 1) a brief description of the GPHS will be provided as background information for the reader; 2) mechanical properties and the optimization thereof as relevant to welding will be discussed; 3) a review of the arc welding process development and optimization will be presented. Since the welding equipment must be upgraded for future production, some discussion of the historical establishment of relevant welding variables and possible changes thereto will also be discussed.

  12. GPACC program cost work breakdown structure-dictionary. General purpose aft cargo carrier study, volume 3

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The results of detailed cost estimates and economic analysis performed on the updated Model 101 configuration of the general purpose Aft Cargo Carrier (ACC) are given. The objective of this economic analysis is to provide the National Aeronautics and Space Administration (NASA) with information on the economics of using the ACC on the Space Transportation System (STS). The detailed cost estimates for the ACC are presented by a work breakdown structure (WBS) to ensure that all elements of cost are considered in the economic analysis and related subsystem trades. Costs reported by WBS provide NASA with a basis for comparing competing designs and provide detailed cost information that can be used to forecast phase C/D planning for new projects or programs derived from preliminary conceptual design studies. The scope covers all STS and STS/ACC launch vehicle cost impacts for delivering payloads to a 160 NM low Earth orbit (LEO).

  13. Fostering ontology alignment sharing: a general-purpose RDF mapping format.

    PubMed

    Anguita, Alberto; Escrich, Ana; Maojo, Victor

    2013-01-01

    RDF has established in the last years as the language for describing, publishing and sharing biomedical resources. Following this trend, a great amount of RDF-based data sources, as well as ontologies, have appeared. Using a common language as RDF has provided a unified syntactic for sharing resources, but the semantics remain as the main cause of heterogeneity, hampering data integration and homogenization efforts. To overcome this issue, ontology alignment based solutions have been typically used. However, alignment information is usually codified using ad-hoc formats. In this paper, we present a general purpose ontology mapping format, totally independent from the homogenization approach to be applied. The format is accompanied with a Java API that offers mapping construction and parsing features, as well as some basic algorithms for applying it to data translation solutions.

  14. User's guide for a general purpose dam-break flood simulation model (K-634)

    USGS Publications Warehouse

    Land, Larry F.

    1981-01-01

    An existing computer program for simulating dam-break floods for forecast purposes has been modified with an emphasis on general purpose applications. The original model was formulated, developed and documented by the National Weather Service. This model is based on the complete flow equations and uses a nonlinear implicit finite-difference numerical method. The first phase of the simulation routes a flood wave through the reservoir and computes an outflow hydrograph which is the sum of the flow through the dam 's structures and the gradually developing breach. The second phase routes this outflow hydrograph through the stream which may be nonprismatic and have segments with subcritical or supercritical flow. The results are discharge and stage hydrographs at the dam as well as all of the computational nodes in the channel. From these hydrographs, peak discharge and stage profiles are tabulated. (USGS)

  15. Forward Modeling of Electromagnetic Methods Using General Purpose Finite Element Software

    NASA Astrophysics Data System (ADS)

    Butler, S. L.

    2015-12-01

    Electromagnetic methods are widely used in mineral exploration and environmental applications and are increasingly being used in hydrocarbon exploration. Forward modeling of electromagnetic methods remains challenging and is mostly carried out using purpose-built research software. General purpose commercial modeling software has become increasingly flexible and powerful in recent years and is now capable of modeling field geophysical electromagnetic techniques. In this contribution, I will show examples of the use of commercial finite element modeling software Comsol Multiphysics for modeling frequency and time-domain electromagnetic techniques as well as for modeling the Very Low Frequency technique and magnetometric resistivity. Comparisons are made with analytical solutions, benchmark numerical solutions, analog experiments and field data. Although some calculations take too long to be practical as part of an inversion scheme, I suggest that modeling of this type will be useful for modeling novel techniques and for educational purposes.

  16. A general purpose subroutine for fast fourier transform on a distributed memory parallel machine

    NASA Technical Reports Server (NTRS)

    Dubey, A.; Zubair, M.; Grosch, C. E.

    1992-01-01

    One issue which is central in developing a general purpose Fast Fourier Transform (FFT) subroutine on a distributed memory parallel machine is the data distribution. It is possible that different users would like to use the FFT routine with different data distributions. Thus, there is a need to design FFT schemes on distributed memory parallel machines which can support a variety of data distributions. An FFT implementation on a distributed memory parallel machine which works for a number of data distributions commonly encountered in scientific applications is presented. The problem of rearranging the data after computing the FFT is also addressed. The performance of the implementation on a distributed memory parallel machine Intel iPSC/860 is evaluated.

  17. Movement analysis of upper limb during resistance training using general purpose robot arm "PA10"

    NASA Astrophysics Data System (ADS)

    Morita, Yoshifumi; Yamamoto, Takashi; Suzuki, Takahiro; Hirose, Akinori; Ukai, Hiroyuki; Matsui, Nobuyuki

    2005-12-01

    In this paper we perform movement analysis of an upper limb during resistance training. We selected sanding training, which is one type of resistance training for upper limbs widely performed in occupational therapy. Our final aims in the future are to quantitatively evaluate the therapeutic effect of upper limb motor function during training and to develop a new rehabilitation training support system. For these purposes, first of all we perform movement analysis using a conventional training tool. By measuring upper limb motion during the sanding training we perform feature abstraction. Next we perform movement analysis using the simulated sanding training system. This system is constructed using the general purpose robot arm "PA10". This system enables us to measure the force/torque exerted by subjects and to easily change the load of resistance. The control algorithm is based on impedance control. We found these features of the upper limb motion during the sanding training.

  18. The ICVSIE: A General Purpose Integral Equation Method for Bio-Electromagnetic Analysis.

    PubMed

    Gomez, Luis J; Yucel, Abdulkadir C; Michielssen, Eric

    2017-05-16

    An internally combined volume surface integral equation (ICVSIE) for analyzing electromagnetic (EM) interactions with biological tissue and wide ranging diagnostic, therapeutic, and research applications, is proposed. The ICVSIE is a system of integral equations in terms of volume and surface equivalent currents in biological tissue subject to fields produced by externally or internally positioned devices. The system is created by using equivalence principles and solved numerically; the resulting current values are used to evaluate scattered and total electric fields, specific absorption rates, and related quantities. The validity, applicability, and efficiency of the ICVSIE are demonstrated by EM analysis of transcranial magnetic stimulation, magnetic resonance imaging, and neuromuscular electrical stimulation. Unlike previous integral equations, the ICVSIE is stable regardless of the electric permittivities of the tissue or frequency of operation, providing an application-agnostic computational framework for EM-biomedical analysis. Use of the general-purpose and robust ICVSIE permits streamlining the development, deployment, and safety analysis of EM-biomedical technologies.

  19. Real-time traffic sign recognition based on a general purpose GPU and deep-learning

    PubMed Central

    Hong, Yongwon; Choi, Yeongwoo; Byun, Hyeran

    2017-01-01

    We present a General Purpose Graphics Processing Unit (GPGPU) based real-time traffic sign detection and recognition method that is robust against illumination changes. There have been many approaches to traffic sign recognition in various research fields; however, previous approaches faced several limitations when under low illumination or wide variance of light conditions. To overcome these drawbacks and improve processing speeds, we propose a method that 1) is robust against illumination changes, 2) uses GPGPU-based real-time traffic sign detection, and 3) performs region detecting and recognition using a hierarchical model. This method produces stable results in low illumination environments. Both detection and hierarchical recognition are performed in real-time, and the proposed method achieves 0.97 F1-score on our collective dataset, which uses the Vienna convention traffic rules (Germany and South Korea). PMID:28264011

  20. An evaluation of alternate production methods for Pu-238 general purpose heat source pellets

    SciTech Connect

    Mark Borland; Steve Frank

    2009-06-01

    For the past half century, the National Aeronautics and Space Administration (NASA) has used Radioisotope Thermoelectric Generators (RTG) to power deep space satellites. Fabricating heat sources for RTGs, specifically General Purpose Heat Sources (GPHSs), has remained essentially unchanged since their development in the 1970s. Meanwhile, 30 years of technological advancements have been made in the applicable fields of chemistry, manufacturing and control systems. This paper evaluates alternative processes that could be used to produce Pu 238 fueled heat sources. Specifically, this paper discusses the production of the plutonium-oxide granules, which are the input stream to the ceramic pressing and sintering processes. Alternate chemical processes are compared to current methods to determine if alternative fabrication processes could reduce the hazards, especially the production of respirable fines, while producing an equivalent GPHS product.

  1. STARS: An integrated general-purpose finite element structural, aeroelastic, and aeroservoelastic analysis computer program

    NASA Technical Reports Server (NTRS)

    Gupta, Kajal K.

    1991-01-01

    The details of an integrated general-purpose finite element structural analysis computer program which is also capable of solving complex multidisciplinary problems is presented. Thus, the SOLIDS module of the program possesses an extensive finite element library suitable for modeling most practical problems and is capable of solving statics, vibration, buckling, and dynamic response problems of complex structures, including spinning ones. The aerodynamic module, AERO, enables computation of unsteady aerodynamic forces for both subsonic and supersonic flow for subsequent flutter and divergence analysis of the structure. The associated aeroservoelastic analysis module, ASE, effects aero-structural-control stability analysis yielding frequency responses as well as damping characteristics of the structure. The program is written in standard FORTRAN to run on a wide variety of computers. Extensive graphics, preprocessing, and postprocessing routines are also available pertaining to a number of terminals.

  2. Computer vision for general purpose visual inspection: a fuzzy logic approach

    NASA Astrophysics Data System (ADS)

    Chen, Y. H.

    In automatic visual industrial inspection, computer vision systems have been widely used. Such systems are often application specific, and therefore require domain knowledge in order to have a successful implementation. Since visual inspection can be viewed as a decision making process, it is argued that the integration of fuzzy logic analysis and computer vision systems provides a practical approach to general purpose visual inspection applications. This paper describes the development of an integrated fuzzy-rule-based automatic visual inspection system. Domain knowledge about a particular application is represented as a set of fuzzy rules. From the status of predefined fuzzy variables, the set of fuzzy rules are defuzzified to give the inspection results. A practical application where IC marks (often in the forms of English characters and a company logo) inspection is demonstrated, which shows a more consistent result as compared to a conventional thresholding method.

  3. General Purpose Graphics Processing Unit Based High-Rate Rice Decompression and Reed-Solomon Decoding

    SciTech Connect

    Loughry, Thomas A.

    2015-02-01

    As the volume of data acquired by space-based sensors increases, mission data compression/decompression and forward error correction code processing performance must likewise scale. This competency development effort was explored using the General Purpose Graphics Processing Unit (GPGPU) to accomplish high-rate Rice Decompression and high-rate Reed-Solomon (RS) decoding at the satellite mission ground station. Each algorithm was implemented and benchmarked on a single GPGPU. Distributed processing across one to four GPGPUs was also investigated. The results show that the GPGPU has considerable potential for performing satellite communication Data Signal Processing, with three times or better performance improvements and up to ten times reduction in cost over custom hardware, at least in the case of Rice Decompression and Reed-Solomon Decoding.

  4. Simrank: Rapid and sensitive general-purpose k-mer search tool

    SciTech Connect

    DeSantis, T.Z.; Keller, K.; Karaoz, U.; Alekseyenko, A.V; Singh, N.N.S.; Brodie, E.L; Pei, Z.; Andersen, G.L; Larsen, N.

    2011-04-01

    Terabyte-scale collections of string-encoded data are expected from consortia efforts such as the Human Microbiome Project (http://nihroadmap.nih.gov/hmp). Intra- and inter-project data similarity searches are enabled by rapid k-mer matching strategies. Software applications for sequence database partitioning, guide tree estimation, molecular classification and alignment acceleration have benefited from embedded k-mer searches as sub-routines. However, a rapid, general-purpose, open-source, flexible, stand-alone k-mer tool has not been available. Here we present a stand-alone utility, Simrank, which allows users to rapidly identify database strings the most similar to query strings. Performance testing of Simrank and related tools against DNA, RNA, protein and human-languages found Simrank 10X to 928X faster depending on the dataset. Simrank provides molecular ecologists with a high-throughput, open source choice for comparing large sequence sets to find similarity.

  5. A General Purpose Connections type CTI Server Based on SIP Protocol and Its Implementation

    NASA Astrophysics Data System (ADS)

    Watanabe, Toru; Koizumi, Hisao

    In this paper, we propose a general purpose connections type CTI (Computer Telephony Integration) server that provides various CTI services such as voice logging where the CTI server communicates with IP-PBX using the SIP (Session Initiation Protocol), and accumulates voice packets of external line telephone call flowing between an IP telephone for extension and a VoIP gateway connected to outside line networks. The CTI server realizes CTI services such as voice logging, telephone conference, or IVR (interactive voice response) with accumulating and processing voice packets sampled. Furthermore, the CTI server incorporates a web server function which can provide various CTI services such as a Web telephone directory via a Web browser to PCs, cellular telephones or smart-phones in mobile environments.

  6. Fully implicit mixed-hybrid finite-element discretization for general purpose subsurface reservoir simulation

    NASA Astrophysics Data System (ADS)

    Abushaikha, Ahmad S.; Voskov, Denis V.; Tchelepi, Hamdi A.

    2017-10-01

    We present a new fully-implicit, mixed-hybrid, finite-element (MHFE) discretization scheme for general-purpose compositional reservoir simulation. The locally conservative scheme solves the coupled momentum and mass balance equations simultaneously, and the fluid system is modeled using a cubic equation-of-state. We introduce a new conservative flux approach for the mass balance equations for this fully-implicit approach. We discuss the nonlinear solution procedure for the proposed approach, and we present extensive numerical tests to demonstrate the convergence and accuracy of the MHFE method using tetrahedral elements. We also compare the method to other advanced discretization schemes for unstructured meshes and tensor permeability. Finally, we illustrate the applicability and robustness of the method for highly heterogeneous reservoirs with unstructured grids.

  7. General purpose software for efficient uncertainty management of large finite element models

    PubMed Central

    Patelli, Edoardo; Murat Panayirci, H.; Broggi, Matteo; Goller, Barbara; Beaurepaire, Pierre; Pradlwarter, Helmut J.; Schuëller, Gerhart I.

    2012-01-01

    The aim of this paper is to demonstrate that stochastic analyses can be performed on large and complex models within affordable costs. Stochastic analyses offer a much more realistic approach for analysis and design of components and systems although generally computationally demanding. Hence, resorting to efficient approaches and high performance computing is required in order to reduce the execution time. A general purpose software that provides an integration between deterministic solvers (i.e. finite element solvers), efficient algorithms for uncertainty management and high performance computing is presented. The software is intended for a wide range of applications, which includes optimization analysis, life-cycle management, reliability and risk analysis, fatigue and fractures simulation, robust design. The applicability of the proposed tools for practical applications is demonstrated by means of a number of case studies of industrial interest involving detailed models. PMID:22474398

  8. THERMAL TESTING OF PROTOTYPE GENERAL PURPOSE FISSILE PACKAGES USING A FURNACE

    SciTech Connect

    Smith, A; Lawrence Gelder, L; Paul Blanton, P

    2007-02-16

    The 9977/9978 General Purpose Fissile Package (GPFP) was designed by SRNL to replace the DOT 6M Specification Package and ship Plutonium and Uranium metals and oxides. Urethane foam was used for the overpack to ensure the package would withstand the 10CFR71.73(c)(2) crush test, which is a severe test for drum-type packages. In addition, it was necessary to confirm that the urethane foam configuration provided adequate thermal protection for the containment vessel during the subsequent 10CFR71.73(c)(4) thermal test. Development tests were performed on early prototype test specimens of different diameter overpacks and a range of urethane foam densities. The thermal test was performed using an industrial furnace. Test results were used to optimize the selection of package diameter and foam density, and provided the basis for design enhancements incorporated into the final package design.

  9. Real-time traffic sign recognition based on a general purpose GPU and deep-learning.

    PubMed

    Lim, Kwangyong; Hong, Yongwon; Choi, Yeongwoo; Byun, Hyeran

    2017-01-01

    We present a General Purpose Graphics Processing Unit (GPGPU) based real-time traffic sign detection and recognition method that is robust against illumination changes. There have been many approaches to traffic sign recognition in various research fields; however, previous approaches faced several limitations when under low illumination or wide variance of light conditions. To overcome these drawbacks and improve processing speeds, we propose a method that 1) is robust against illumination changes, 2) uses GPGPU-based real-time traffic sign detection, and 3) performs region detecting and recognition using a hierarchical model. This method produces stable results in low illumination environments. Both detection and hierarchical recognition are performed in real-time, and the proposed method achieves 0.97 F1-score on our collective dataset, which uses the Vienna convention traffic rules (Germany and South Korea).

  10. General-purpose heat source safety verification test series: SVT-11 through SVT-13

    SciTech Connect

    George, T.G.; Pavone, D.

    1986-05-01

    The General-Purpose Heat Source (GPHS) is a modular component of the radioisotope thermoelectric generator that will provide power for the Galileo and Ulysses (formerly ISPM) space missions. The GPHS provides power by transmitting the heat of /sup 238/Pu ..cap alpha..-decay to an array of thermoelectric elements. Because the possibility of an orbital abort always exists, the heat source was designed and constructed to minimize plutonia release in any accident environment. The Safety Verification Test (SVT) series was formulated to evaluate the effectiveness of GPHS plutonia containment after atmospheric reentry and Earth impact. The first two reports (covering SVT-1 through SVT-10) described the results of flat, side-on, and angular module impacts against steel targets at 54 m/s. This report describes flat-on module impacts against concrete and granite targets, at velocities equivalent to or higher than previous SVTs.

  11. [Estimation of T1 and T2 using general-purpose spreadsheet software].

    PubMed

    Kawamata, Wataru; Toyoshima, Hideto

    2009-03-20

    We performed an estimation of longitudinal (T1) and transverse relaxation (T2) time using the general-purpose spreadsheet software Microsoft Excel. The Excel tool "solver" is useful for the simultaneous estimation of both T1 and steady-state magnetization from the non-linear least square method. The estimation time is quick enough for the purpose. T1 and T2 estimated from handwritten semi-log plots were compared with the results from spreadsheet software from the viewpoint of accuracy using the phantom data. Although the data from handwritten plots include an estimation error of several percent among the subjects, the mean values are almost the same as compared with the data from spreadsheet software.

  12. Characterization of the general purpose research furnace for low-G directional solidification experiments

    NASA Technical Reports Server (NTRS)

    Crouch, R. K.; Fripp, A. L.; Debnam, W. J.; Clark, I. O.; Zweiner, J. W.; Carlson, F. M.

    1983-01-01

    Preliminary tests have shown that it is possible to control the temperature settings in NASA's General Purpose Research Furnace in such a manner as to obtain a constant rate of movement of a high temperature isotherm down the length of the furnace. These tests also showed that a temperature gradient on the order of 40 deg cm could be obtained in the furnace while moving the particular isotherm of interest, i.e., 900 C. This provides the possibility of performing directional solidification experiments in the furnace on a MEA flight in the low gravity environment provided by the Shuttle. A functional dependency of growth rate on perturbations during the the growth has been derived and shows the importance of avoiding non-steady growth rates and changing temperature gradients.

  13. General-purpose stepping motor-encoder positioning subsystem with standard asynchronous serial-line interface

    SciTech Connect

    Stubblefield, F.W.; Alberi, J.L.

    1982-01-01

    A general-purpose mechanical positioning subsystem for open-loop control of experiment devices which have their positions established and read out by stepping motor-encoder combinations has been developed. The subsystem is to be used mainly for experiments to be conducted at the National Synchrotron Light Source at Brookhaven National Laboratory. The subsystem unit has been designed to be compatible with a wide variety of stepping motor and encoder types. The unit may be operated by any device capable of driving a standard RS-232-C asynchronous serial communication line. An informal survey has shown that several experiments at the Light Source will use one particular type of computer, operating system, and programming language. Accordingly, a library of subroutines compatible with this combination of computer system elements has been written to facilitate driving the positioning subsystem unit.

  14. A general purpose cold finger using a vibration-free mounted He closed-cycle cryostata)

    NASA Astrophysics Data System (ADS)

    Boolchand, P.; Lemon, G. H.; Bresser, W. J.; Enzweiler, R. N.; Harris, R.

    1995-04-01

    A method for mounting a He closed-cycle cryostat which consists of an exchange gas envelope around the cold head to cool an independently supported sample mount as in model DE202 with a DMX-20 interface from APD Cryogenics, Inc. is described. No detectable vibration of the sample mount is observed as evaluated using 57Fe Mössbauer spectroscopy and a piezoelectric accelerometer. Using a 25 μm thick α-Fe foil a linewidth of 0.231(3) mm/s at 300 K with the refrigerator on and the same linewidth with the refrigerator off is observed. The easy optical access afforded by such a cold finger makes it an economical general purpose laboratory tool for performing low-T spectroscopic investigations, such as microwave, optical, γ-ray, x-ray and neutron-scattering measurements. Other applications include electrical transport, SIMS, RBS, and rare-gas matrix isolation.

  15. General purpose dynamic Monte Carlo with continuous energy for transient analysis

    SciTech Connect

    Sjenitzer, B. L.; Hoogenboom, J. E.

    2012-07-01

    For safety assessments transient analysis is an important tool. It can predict maximum temperatures during regular reactor operation or during an accident scenario. Despite the fact that this kind of analysis is very important, the state of the art still uses rather crude methods, like diffusion theory and point-kinetics. For reference calculations it is preferable to use the Monte Carlo method. In this paper the dynamic Monte Carlo method is implemented in the general purpose Monte Carlo code Tripoli4. Also, the method is extended for use with continuous energy. The first results of Dynamic Tripoli demonstrate that this kind of calculation is indeed accurate and the results are achieved in a reasonable amount of time. With the method implemented in Tripoli it is now possible to do an exact transient calculation in arbitrary geometry. (authors)

  16. Generic functional requirements for a NASA general-purpose data base management system

    NASA Technical Reports Server (NTRS)

    Lohman, G. M.

    1981-01-01

    Generic functional requirements for a general-purpose, multi-mission data base management system (DBMS) for application to remotely sensed scientific data bases are detailed. The motivation for utilizing DBMS technology in this environment is explained. The major requirements include: (1) a DBMS for scientific observational data; (2) a multi-mission capability; (3) user-friendly; (4) extensive and integrated information about data; (5) robust languages for defining data structures and formats; (6) scientific data types and structures; (7) flexible physical access mechanisms; (8) ways of representing spatial relationships; (9) a high level nonprocedural interactive query and data manipulation language; (10) data base maintenance utilities; (11) high rate input/output and large data volume storage; and adaptability to a distributed data base and/or data base machine configuration. Detailed functions are specified in a top-down hierarchic fashion. Implementation, performance, and support requirements are also given.

  17. Using a general purpose finite element approach to attain higher fidelity rotordynamic analyses

    NASA Astrophysics Data System (ADS)

    Gyekenyesi, Andrew L.; Wroblewski, Adam C.

    2015-04-01

    By utilizing a general purpose finite element (FE) code, the dynamic response of a rotor system was numerically studied in order to assess physical effects that are typically not taken into account using traditional rotordynamic codes. This included the allowance for disk flexibility as well as conducting a simultaneous heat transfer analysis that resulted in varying temperatures in the axial and radial directions. The numerical study utilized a generic, multi-disk model with a flexible hollow shaft. The Campbell diagrams and the mode shapes showed that neglecting any of the additional influences may cause errors regarding the predicted rotor dynamic response. By increasing the fidelity of the rotor model and accounting for the various effects, the slight signal modifications due to damage can be more easily recognized allowing for increased accuracy during rotor health monitoring.

  18. Interfacing a General Purpose Fluid Network Flow Program with the SINDA/G Thermal Analysis Program

    NASA Technical Reports Server (NTRS)

    Schallhorn, Paul; Popok, Daniel

    1999-01-01

    A general purpose, one dimensional fluid flow code is currently being interfaced with the thermal analysis program Systems Improved Numerical Differencing Analyzer/Gaski (SINDA/G). The flow code, Generalized Fluid System Simulation Program (GFSSP), is capable of analyzing steady state and transient flow in a complex network. The flow code is capable of modeling several physical phenomena including compressibility effects, phase changes, body forces (such as gravity and centrifugal) and mixture thermodynamics for multiple species. The addition of GFSSP to SINDA/G provides a significant improvement in convective heat transfer modeling for SINDA/G. The interface development is conducted in multiple phases. This paper describes the first phase of the interface which allows for steady and quasi-steady (unsteady solid, steady fluid) conjugate heat transfer modeling.

  19. GPP user`s guide - a general-purpose postprocessor for wind turbine data analysis

    SciTech Connect

    Buhl, Jr, M L

    1995-01-01

    GPP (pronounced {open_quotes}jeep{close_quotes}) is a General-Purpose Postprocessor for wind turbine data analysis. The author, a member of the Wind Technology Division (WTD) of the National Renewable Energy Laboratory (NREL), developed GPP to postprocess test data and simulation predictions. GPP reads data into large arrays and allows the user to run many types of analyses on the data stored in memory. It runs on inexpensive computers common in the wind industry. One can even use it on a laptop in the field. The author wrote the program in such a way as to make it easy to add new types of analyses and to port it to many types of computers. Although GPP is very powerful and feature-rich, it is still very easy to learn and to use. Exhaustive error trapping prevents one from losing valuable work due to input errors. GPP will, hopefully, make a significant impact on engineering productivity in the wind industry.

  20. General-purpose heat source safety verification test series: SVT-11 through SVT-13

    NASA Astrophysics Data System (ADS)

    George, T. G.; Pavone, D.

    1986-05-01

    The General-Purpose Heat Source (GPHS) is a modular component of the radioisotope thermoelectric generator that will provide power for the Galileo and Ulysses (formerly ISPM) space missions. The GPHS provides power by transmitting the heat of Pu -decay to an array of thermoelectric elements. Because the possibility of an orbital abort always exists, the heat source was designed and constructed to minimize plutonia release in any accident environment. The Safety Verification Test (SVT) series was formulated to evaluate the effectiveness of GPHS plutonia containment after atmospheric reentry and Earth impact. The first two reports (covering SVT-1 through SVT-10) described the results of flat, side-on, and angular module impacts against steel targets at 54 m/s. This report describes flat-on module impacts against concrete and granite targets, at velocities equivalent to or higher than previous SVTs.

  1. General-purpose heat source safety verification test series: SVT-7 through SVT-10

    NASA Astrophysics Data System (ADS)

    George, T. G.; Pavone, D.

    1985-09-01

    The General-Purpose Heat Source (GPHS) is a modular component of the radioisotope thermoelectric generator that will supply power for the Galileo and Ulysses (formerly ISPM) space missions. The GPHS provides power by transmitting the heat of (238)PuO2 (ALPHA)-decay to an array of thermoelectric elements. Because the possibility of an orbital abort always exists, the heat source was designed and constructed to minimize plutonia release in any accident environment. The Safety Verification Test (SVT) series was formulated to evaluate the effectiveness of GPHS plutonia containment after atmospheric reentry and Earth impact. The first report (covering SVT-1 through SVT-6) described the results of flat and side-on module impacts. This report describes module impacts at angles of 15(0) and 30(0).

  2. Strong scaling of general-purpose molecular dynamics simulations on GPUs

    NASA Astrophysics Data System (ADS)

    Glaser, Jens; Nguyen, Trung Dac; Anderson, Joshua A.; Lui, Pak; Spiga, Filippo; Millan, Jaime A.; Morse, David C.; Glotzer, Sharon C.

    2015-07-01

    We describe a highly optimized implementation of MPI domain decomposition in a GPU-enabled, general-purpose molecular dynamics code, HOOMD-blue (Anderson and Glotzer, 2013). Our approach is inspired by a traditional CPU-based code, LAMMPS (Plimpton, 1995), but is implemented within a code that was designed for execution on GPUs from the start (Anderson et al., 2008). The software supports short-ranged pair force and bond force fields and achieves optimal GPU performance using an autotuning algorithm. We are able to demonstrate equivalent or superior scaling on up to 3375 GPUs in Lennard-Jones and dissipative particle dynamics (DPD) simulations of up to 108 million particles. GPUDirect RDMA capabilities in recent GPU generations provide better performance in full double precision calculations. For a representative polymer physics application, HOOMD-blue 1.0 provides an effective GPU vs. CPU node speed-up of 12.5 ×.

  3. Modification of hot cells for general purpose heat source assembly at the radioisotope power systems facility

    NASA Astrophysics Data System (ADS)

    Carteret, Betty A.

    1992-01-01

    Eight existing, unused hot cells currently are being modified for use in the Radioisotope Power Systems Facility (RPSF) to assemble 238Pu-fueled heat sources for Radioisotope Thermoelectric Generators (RTGs). Four air atmosphere cells will be used for storage, decanning, and decontamination of the iridium-clad radioisotope fuel. The remaining four argon atmosphere cells will be used to assemble fuel and graphite components for production and packaging of general purpose heat source (GPHS) assembly modules, which provide heat to drive the thermoelectric conversion process in the generators. The hot cells will be equipped to perform remote and glovebox-type operations. They will provide shielding and contamination control measures to reduce worker radiation exposure to levels within current U.S. Department of Energy (DOE) guidelines. Designs emphasize the Westinghouse Hanford Company (Westinghouse Hanford) as low as reasonably achievable (ALARA) radiation protection policy.

  4. Modification of hot cells for general purpose heat source assembly at the Radioisotope Power Systems Facility

    NASA Astrophysics Data System (ADS)

    Carteret, B. A.

    1991-09-01

    Eight existing, unused hot cells currently are being modified for use in the Radioisotope Power Systems Facility (RPSF) to assemble Pu-238 fueled heat sources for radioisotope thermoelectric generators (RTGs). Four air atmosphere cells will be used for storage, decanning, and decontamination of the iridium-clad radioisotope fuel. The remaining four argon atmosphere cells will be used to assemble fuel and graphite components for production and packaging of general purpose heat source (GPHS) assembly modules, which provide heat to drive the thermoelectric conversion process in the generators. The hot cells will be equipped to perform remote and glovebox-type operations. They will provide shielding and contamination control measures to reduce worker radiation exposure to levels within current U.S. Department of Energy (DOE) guidelines. Designs emphasize the Westinghouse Hanford Company (Westinghouse Hanford) as low as reasonably achievable (ALARA) radiation protection policy.

  5. Design of the SLAC RCE Platform: A General Purpose ATCA Based Data Acquisition System

    SciTech Connect

    Herbst, R.; Claus, R.; Freytag, M.; Haller, G.; Huffer, M.; Maldonado, S.; Nishimura, K.; O'Grady, C.; Panetta, J.; Perazzo, A.; Reese, B.; Ruckman, L.; Thayer, J. G.; Weaver, M.

    2015-01-23

    The SLAC RCE platform is a general purpose clustered data acquisition system implemented on a custom ATCA compliant blade, called the Cluster On Board (COB). The core of the system is the Reconfigurable Cluster Element (RCE), which is a system-on-chip design based upon the Xilinx Zynq family of FPGAs, mounted on custom COB daughter-boards. The Zynq architecture couples a dual core ARM Cortex A9 based processor with a high performance 28nm FPGA. The RCE has 12 external general purpose bi-directional high speed links, each supporting serial rates of up to 12Gbps. 8 RCE nodes are included on a COB, each with a 10Gbps connection to an on-board 24-port Ethernet switch integrated circuit. The COB is designed to be used with a standard full-mesh ATCA backplane allowing multiple RCE nodes to be tightly interconnected with minimal interconnect latency. Multiple shelves can be clustered using the front panel 10-gbps connections. The COB also supports local and inter-blade timing and trigger distribution. An experiment specific Rear Transition Module adapts the 96 high speed serial links to specific experiments and allows an experiment-specific timing and busy feedback connection. This coupling of processors with a high performance FPGA fabric in a low latency, multiple node cluster allows high speed data processing that can be easily adapted to any physics experiment. RTEMS and Linux are both ported to the module. The RCE has been used or is the baseline for several current and proposed experiments (LCLS, HPS, LSST, ATLAS-CSC, LBNE, DarkSide, ILC-SiD, etc).

  6. Coating-free mirrors for high precision interferometric experiments

    SciTech Connect

    Gossler, Stefan; Cumpston, Jeff; McKenzie, Kirk; Mow-Lowry, Conor M.; Gray, Malcolm B.; McClelland, David E.

    2007-11-15

    Thermal noise in mirror optical coatings may not only limit the sensitivity of future gravitational-wave detectors in their most sensitive frequency band but is also a major impediment for experiments that aim to reach the standard quantum limit or cool mechanical systems to their quantum ground state. We present the design and experimental characterization of a highly reflecting mirror without any optical coating. This coating-free mirror is based on total internal reflection and Brewster-angle coupling. In order to characterize its performance, the coating-free mirror was incorporated into a triangular ring cavity together with a high quality conventional mirror. The finesse of this cavity was measured using an amplitude transfer function to be about F{approx_equal}4000. This finesse corresponds to a reflectivity of the coating-free mirror of about R{approx_equal}99.89%. In addition, the dependence of the reflectivity on rotation was mapped out.

  7. High precision measurement and analysis of colloidal monolayers

    PubMed Central

    Milne, Graham; Zhao, Yongxi; Chiu, Daniel T.

    2010-01-01

    This paper describes an imaging algorithm for analyzing colloidal monolayers, including the measurement of particle-to-particle distances with nanometer-scale resolution, the automated detection of defects and edges, as well as determining the uniformity of the colloid size distribution. The algorithm also allows for the automatic detection and measurement of scaling introduced by non-square detector pixels - a common problem in imaging. As an application, we demonstrate the use of this method for spatially calibrating digital video microscopy systems that can be applied in situations where conventional methods may be inappropriate. Here, we provide an overview of the workings of the algorithm, which we have made freely available. PMID:20353161

  8. High Precision Differential Photometry with CCDs: A Brief History

    NASA Astrophysics Data System (ADS)

    Howell, Steve B.

    I present a brief history of the hunt for high photometric precision using CCDs in astronomy. CCDs were invented in 1969 and only 7 years later they started to appear at the major observatories of the time. The next 10 years constituted a steep learning curve for astronomers as they developed an understanding of CCDs as instruments and analysis techniques for use with digital images. In 1985, differential photometry with CCDs began producing light curves with precisions near 0.01 magnitude. By 2008, ground-based telescopes armed with CCDs and using differential techniques consistently can provide photometric precisions of 1 millimagnitude or better. The challenge now is to continue to improve the photometry using new types of CCD detectors and other advanced digital imagers.

  9. High Precision 40K/39K Ratio Determination

    NASA Astrophysics Data System (ADS)

    Naumenko, M. O.; Mezger, K.; Nagler, T. F.; Villa, I. M.

    2012-12-01

    Potassium is one of the eight most abundant chemical elements in the Earth's crust and a major element in many rock-forming minerals. The isotope 40K is radioactive and undergoes β- decay to 40Ca (ca. 89.3%) and electron capture to 40Ar (ca. 10.7%). Both decays can potentially be used as dating systems. The most commonly used branch is the decay of 40K to 40Ar because it can yield highly precise ages. Both decay schemes rely on the knowledge of the 40K branching ratio and the natural 40K abundance. A 40K abundance of 0.011672±41 % was measured on terrestrial material [1]. The relative uncertainty of 0.35 % has not been improved since. Recent improvements in the precision of mass spectrometric measurements have led to the situation that the uncertainties on the K decay constant and the abundance of 40K are a major source of uncertainty on the measured ages. A more precise definition of the 40K decay constant was attempted by different research groups within the last decade [2-9] but the goal of obtaining 0.1 % relative uncertainty on K-Ar ages for geological materials, as requested by the EARTHtime initiative, has not been achieved yet. In order to improve on this situation we studied the abundances of the K isotopes in terrestrial standards. A ThermoFischer Triton+ thermal ionisation mass spectrometer was used for K isotope ratio measurements of the NIST SRM 918b K standard loaded on Ta filaments with 0.1M phosphoric acid. Three techniques were applied: (A) dynamic measurement with in-run normalisation to the IUPAC value 41K/39K=0.072168; (B) a simple total evaporation procedure; (C) the "NBL-modified" total evaporation [10]. The 40K ion beam was measured in a Faraday cup with a 1E12 Ω resistor; 39K and 41K were collected in Faraday cups with 1E11 Ω resistors. Amplifier gains were intercalibrated by supplying fixed voltages off-line. Different measurement techniques were combined with different loading procedures. We also tested ionisation yields for the

  10. High precision ages from the Torres del Paine Intrusion, Chile

    NASA Astrophysics Data System (ADS)

    Michel, J.; Baumgartner, L.; Cosca, M.; Ovtcharova, M.; Putlitz, B.; Schaltegger, U.

    2006-12-01

    The upper crustal bimodal Torres del Paine Intrusion, southern Chile, consists of the lower Paine-Mafic- Complex and the upper Paine-Granite. Geochronologically this bimodal complex is not well studied except for a few existing data from Halpern (1973) and Sanchez (2006). The aim of this study is to supplement the existing data and to constrain the age relations between the major magmatic pulses by applying high precision U-Pb dating on accessory zircons and 40Ar/39Ar-laser-step-heating-ages on biotites from the Torres del Paine Intrusion. The magmatic rocks from mafic complex are fine to medium-grained and vary in composition from quartz- monzonites to granodiorites and gabbros. Coarse-grained olivine gabbros have intruded these rocks in the west. The granitic body is represented by a peraluminous, biotite-orthoclase-granite and a more evolved leucocratic granite in the outer parts towards the host-rock. Field observations suggest a feeder-zone for the granite in the west and that the granite postdates the mafic complex. Two granite samples of the outermost margins in the Northeast and South were analyzed. The zircons were dated by precise isotope-dilution U-Pb techniques of chemically abraded single grains. The data are concordant within the analytical error and define weighted mean 206/238U ages of 12.59 ± 0.03 Ma and 12.58 ± 0.01 Ma for the two samples respectively. A 40Ar/39Ar-age for the second sample yield a date of 12.37 ± 0.11 Ma. Three 40Ar/39Ar -ages of biotites were obtained for rocks belonging to the mafic complex. A hbl-bio- granodiorite from the central part, approximately 150 m below the subhorizontal contact with the granite, gives an age of 12.81 ± 0.11 Ma. A hbl-bio-granodiorite and an olivine-gabbro west of the feeder-zone date at 12.42 ± 0.14 Ma and 12.49 ± 0.11 Ma, respectively. The obtained older age of 12.81 Ma for the granodiorite in the central part is consistent with structural relationships of brittle fracturing of the mafic

  11. High-precision Mg isotopic systematics of bulk chondrites

    NASA Astrophysics Data System (ADS)

    Schiller, Martin; Handler, Monica R.; Baker, Joel A.

    2010-08-01

    Variations of the mass-independent abundance of 26Mg ( δ26Mg*) and stable Mg ( δ25Mg) isotope composition of chondrites are important because they constrain the homogeneity of 26Al and Mg isotopes in the proto-planetary disc and the validity of the short-lived 26Al-to- 26Mg chronometer applied to meteorites. We present high-precision Mg isotope data and Al/Mg ratios of chondrites representing nearly all major chondrite classes, including a step-leaching experiment on the CM2 chondrite Murchison. δ26Mg* variations in leachates of Murchison representing acid soluble material are ≤ 30 times smaller than reported for neutron-rich isotopes of Ti and Cr and do not reveal resolvable deficits in δ26Mg* (-0.002 to + 0.118‰). Very small variations in δ26Mg* anomalies in bulk chondrites (-0.006 to + 0.019‰) correlate with increasing 27Al/ 24Mg ratios and δ50Ti, reflecting the variable presence of calcium-aluminium-rich inclusions (CAIs) in some types of carbonaceous chondrites. Similarly, release of radiogenic 26Mg produced by 26Al decay from CAI material in the step-leaching of Murchison best explains the high δ26Mg* observed in the last, aggressive, leaching steps of this experiment. Overall, the observed variations in δ26Mg* are small and potential differences beyond that which result from the presence of CAI-like material cannot be detected within the analytical uncertainties of this study (± 0.004‰). The results do not allow radical heterogeneity of 26Al (≥±30%) or measurable Mg nucleosynthetic heterogeneity (≥±0.005‰) to have existed on a planetesimal scale in the proto-planetary disc. Combined with published δ26Mg* data for CAIs, the bulk chondrite data yield a precise initial ( 26Al/ 27Al) 0 = (5.21 ± 0.06) × 10 -5 and δ26Mg* = -0.0340 ± 0.0016‰ for the Solar System. However, it is not possible with the currently available data to determine with certainty whether CAIs and the material from which planetesimals accreted including

  12. The 40m General Purpose Small-Angle Neutron Scattering Instrument at Oak Ridge National Laboratory

    SciTech Connect

    Wignall, George D; Bailey, Katherine M; Buchanan, Michelle V; Butler, Paul D; Heller, William T; Littrell, Ken; Lynn, Gary W; Melnichenko, Yuri B; Myles, Dean A A; Urban, Volker S

    2012-01-01

    A high-flux, 40m long small-angle neutron scattering (SANS) instrument has been constructed at Oak Ridge National Laboratory (ORNL). The facility utilizes a mechanical velocity selector, pinhole collimation and a high count-rate (> 105 Hz), large-area (1m2) two-dimensional position-sensitive detector. The incident wavelength ( ), resolution ( / ), incident collimation and sample-detector distance are independently variable under computer control. The detector can translate 45cm off axis to increase the overall Q-range (< 0.001 < Q = 4 -1sin < 1 -1), where 2 is the angle of scatter. The design and characteristics of this instrument are described along with examples of scattering data to illustrate the performance.

  13. Development of Metallic Magnetic Calorimeters for High Precision Measurements of Calorimetric Re-187 and Ho-163 Spectra

    NASA Technical Reports Server (NTRS)

    Ranitzsch, P. C.-O.; Porst, J.-P.; Kempf, S.; Pies, C.; Schafer, S.; Hengstler, D.; Fleischmann, A.; Enss, C.; Gastaldo, L.

    2012-01-01

    The measurement of calorimetric spectra following atomic weak decays, beta (b) and electron capture (EC), of nuclides having a very low Q-value, can provide an impressively high sensitivity to a non-vanishing neutrino mass. The achievable sensitivity in this kind of experiments is directly connected to the performance of the used detectors. In particular an energy resolution of a few eV and a pulse formation time well below 1 microsecond are required. Low temperature Metallic Magnetic Calorimeters (MMCs) for soft X-rays have already shown an energy resolution of 2.0 eV FWHM and a pulse rise-time of about 90 ns for fully micro-fabricated detectors. We present the use of MMCs for high precision measurements of calorimetric spectra following the beta-decay of Re-187 and the EC of Ho-163. We show results obtained with detectors optimized for Re-187 and for Ho-163 experiments respectively. While the detectors equipped with superconducting Re absorbers have not yet reached the aimed performance, a first detector prototype with a Au absorber having implanted Ho-163 ions already shows excellent results. An energy resolution of 12 eV FWHM and a rise time of 90 ns were measured.

  14. Development of Metallic Magnetic Calorimeters for High Precision Measurements of Calorimetric Re-187 and Ho-163 Spectra

    NASA Technical Reports Server (NTRS)

    Ranitzsch, P. C.-O.; Porst, J.-P.; Kempf, S.; Pies, C.; Schafer, S.; Hengstler, D.; Fleischmann, A.; Enss, C.; Gastaldo, L.

    2012-01-01

    The measurement of calorimetric spectra following atomic weak decays, beta (b) and electron capture (EC), of nuclides having a very low Q-value, can provide an impressively high sensitivity to a non-vanishing neutrino mass. The achievable sensitivity in this kind of experiments is directly connected to the performance of the used detectors. In particular an energy resolution of a few eV and a pulse formation time well below 1 microsecond are required. Low temperature Metallic Magnetic Calorimeters (MMCs) for soft X-rays have already shown an energy resolution of 2.0 eV FWHM and a pulse rise-time of about 90 ns for fully micro-fabricated detectors. We present the use of MMCs for high precision measurements of calorimetric spectra following the beta-decay of Re-187 and the EC of Ho-163. We show results obtained with detectors optimized for Re-187 and for Ho-163 experiments respectively. While the detectors equipped with superconducting Re absorbers have not yet reached the aimed performance, a first detector prototype with a Au absorber having implanted Ho-163 ions already shows excellent results. An energy resolution of 12 eV FWHM and a rise time of 90 ns were measured.

  15. Design of a high-precision β-telescope

    NASA Astrophysics Data System (ADS)

    Terbeek, R. H.; Behling, S.; Melconian, D.

    2009-10-01

    The question is raised of whether or not parity is maximally violated in the weak interaction, focusing on β decay. Efforts to measure the neutrino asymmetry parameter, Bν, and how it will provide limits on the existence of a new right-handed W boson are described. In this experiment, a magneto-optical trap is used to laser-cool and confine ^37K atoms, which are then polarized using optical pumping techniques. A β-telescope will be used to detect the energy and direction of the e^+s emitted from the decay. This detector will be used in coincidence with a microchannel plate which observes the momentum of the recoiling ^37Ar nucleus. The kinematics of the decay allow us to deduce the neutrino's momentum event-by-event, and so by correlating the neutrino's momentum with the initial nuclear spin, we will be able to make a precision measurement of Bν. The physics of positron detection and constraints on β-telescope design are covered in detail, as well as research into computer simulation methods for the analysis of response functions and the optimization of certain parameters of a β-telescope.

  16. High Precision Bright-Star Astrometry with the USNO Astrometric CMOS Hybrid Camera System

    NASA Astrophysics Data System (ADS)

    Secrest, Nathan; Dudik, Rachel; Berghea, Ciprian; Hennessy, Greg; Dorland, Bryan

    2015-08-01

    While GAIA will provide excellent positional measurements of hundreds of millions of stars between 5 < mag < 20, an ongoing challenge in the field of high-precision differential astrometry is the positional accuracy of very bright stars (mag < 5), due to the enormous dynamic range between bright stars of interest, such as those in the Hipparcos catalog, and their background field stars, which are especially important for differential astrometry. Over the past few years, we have been testing the USNO Astrometric CMOS Hybrid Camera System (UAHC), which utilizes an H4RG-10 detector in windowing mode, as a possible solution to the NOFS USNO Bright Star Astrometric Database (UBAD). In this work, we discuss the results of an astrometric analysis of single-epoch Hipparcos data taken with the UAHC from the 1.55m Kaj Strand Astrometric Reflector at NOFS from June 27-30, 2014. We discuss the calibration of this data, as well as an astrometric analysis pipeline we developed that will enable multi-epoch differential and absolute astrometry with the UAHC. We find that while the overall differential astrometric stability of data taken with the UAHC is good (5-10 mas single-measurement precision) and comparable to other ground-based astrometric camera systems, bright stars in the detector window suffer from several systematic effects, such as insufficient window geometry and centroiding failures due to read-out artifacts—both of which can be significantly improved with modifications to the electronics, read-out speed and microcode.

  17. High Precision Calculations of the Lennard-Jones Lattice Constants for Five Lattices

    NASA Astrophysics Data System (ADS)

    Stein, Matthew

    2017-01-01

    The total potential energy of a crystal as described by the Lennard-Jones (L-J) potential depends in part upon the calculation of lattice constants. Knowing these constants to high precision is useful for prediction of the lattice type and simulation of crystals such as rare-gas solids or germanium detectors, but reaching higher precision is computationally costly and challenging. Presented here is the extension of the precision of the lattice constants, Lp, up to 32 decimal digits, and in some cases corrections from previous publication. The Lp terms are given for 4 <= p <= 30 in the simple cubic, face-centered cubic, body-centered cubic, hexagonal-close-pack, and diamond lattices. This precision was obtained through the use of careful parallelization technique, exploitation of the symmetries of each lattice, and the ``onionization'' of the simulated crystal. The results of this computation, along with the tools and algorithm strategies to make this computation possible, are explained in detail graphically.

  18. High precision carbon-interspaced antiscatter grids: Performance testing and moiré pattern analysis

    NASA Astrophysics Data System (ADS)

    Lee, S. J.; Cho, H. S.; Oh, J. E.; Choi, S. I.; Cho, H. M.; Park, Y. O.; Hong, D. K.; Lee, M. S.; Yang, Y. J.; Je, U. K.; Kim, D. S.; Lee, H. K.

    2011-10-01

    Recently, we have developed high precision carbon-interspaced antiscatter grids to be suitable for digital radiography (DR) adopting a precise sawing process. For systematic evaluation of the grid performance, we prepared several sample grids having different grid frequencies (4.0-8.5 lines/mm) and grid ratios (5:1-10:1) and established a well-controlled test condition based upon the IEC standard. In this paper, we presented the performance characteristics of the carbon-interspaced grids in terms of the transmission of primary radiation ( Tp), the transmission of scattered radiation ( Ts), the transmission of total radiation ( Tt), contrast improvement factor ( Cif), and Bucky factor ( B). We also described the grid line artifact, known as a moiré pattern, which may be the most critical problem to be solved for the successful grid use in DR. We examined the factors that affect the moiré pattern by integrating the sample grids with an a-Se based flat panel detector having a 139 μm×139 μm pixel size.

  19. Development of high precision laser measurement to Space Debris and Applications in SHAO

    NASA Astrophysics Data System (ADS)

    Zhang, Zhongping; Chen, Juping; Xiong, Yaoheng; Han, Xingwei

    2016-07-01

    Artificial space debris has become the focus during the space exploration because of producing the damage for the future active spacecrafts and high precision measurement for space debris are required for debris surveillance and collision avoidance. Laser ranging technology is inherently high accurate and will play an important role in precise orbit determination, accurate catalog of space debris. Shanghai Astronomical Observatory (SHAO) of CAS, has been developing the technology of laser measurement to space debris for several years. According to characteristics of laser echoes from space debris and the experiences of relevant activities, high repetition rate, high power laser system and low dark noise APD detector with high quantum efficiency and high transmissivity of narrow bandwidth spectral filter are applied to laser measurement to space debris in SHAO. With these configurations, great achievements of laser measurement to space debris are made with hundreds of passes of laser data from space debris in the distance between 500km and 2500km with Radar Cross Section (RCS) of more than 10 m^{2} to less than 0.5m^{2} at the measuring precision of less than 1m (RMS). For better application of laser ranging technology, Chinese Space Debris Observation network, consisting of Shanghai, Changchun and Kunming station, has been preliminary developed and the coordinated observation has been performed to increase the measuring efficiency for space debris. It is referred from data that laser ranging technology can be as the essential high accuracy measurement technology in the study of space debris.

  20. Radio emission from Supernovae and High Precision Astrometry

    NASA Astrophysics Data System (ADS)

    Perez-Torres, M. A.

    1999-11-01

    The present thesis work makes contributions in two scientific fronts: differential astrometry over the largest angular scales ever attempted (approx. 15 arcdegrees) and numerical simulations of radio emission from very young supernovae. In the first part, we describe the results of the use of very-long-baseline interferometry (VLBI) in one experiment designed to measure with very high precision the angular distance between the radio sources 1150+812 (QSO) and 1803+784 (BL Lac). We observed the radio sources on 19 November 1993 using an intercontinental array of radio telescopes, which simultaneously recorded at 2.3 and 8.4 GHz. VLBI differential astrometry is capable, Nature allowing, of yielding source positions with precisions well below the milliarcsecond level. To achieve this precision, we first had to accurately model the rotation of the interferometric fringes via the most precise models of Earth Orientation Parameters (EOP; precession, polar motion and UT1, nutation). With this model, we successfully connected our phase delay data at both frequencies and, using difference astrometric techniques, determined the coordinates of 1803+784 relative to those of 1150+812-within the IERS reference frame--with an standard error of about 0.6 mas in each coordinate. We then corrected for several effects including propagation medium (mainly the atmosphere and ionosphere), and opacity and source-structure effects within the radio sources. We stress that our dual-frequency measurements allowed us to accurately subtract the ionosphere contribution from our data. We also used GPS-based TEC measurements to independently find the ionosphere contribution, and showed that these contributions agree with our dual-frequency measurements within about 2 standard deviations in the less favorables cases (the longest baselines), but are usually well within one standard deviation. Our estimates of the relative positions, whether using dual-frequency-based or GPS-based ionosphere

  1. General-purpose heat source project and space nuclear safety and fuels program. Progress report

    SciTech Connect

    Maraman, W.J.

    1980-02-01

    Studies related to the use of /sup 238/PuO/sub 2/ in radioisotopic power systems carried out for the Advanced Nuclear Systems and Projects Division of LASL are presented. The three programs involved are: general-purpose heat source development; space nuclear safety; and fuels program. Three impact tests were conducted to evaluate the effects of a high temperature reentry pulse and the use of CBCF on impact performance. Additionally, two /sup 238/PuO/sub 2/ pellets were encapsulated in Ir-0.3% W for impact testing. Results of the clad development test and vent testing are noted. Results of the environmental tests are summarized. Progress on the Stirling isotope power systems test and the status of the improved MHW tests are indicated. The examination of the impact failure of the iridium shell of MHFT-65 at a fuel pass-through continued. A test plan was written for vibration testing of the assembled light-weight radioisotopic heater unit. Progress on fuel processing is reported.

  2. Applications of artificial intelligence to space station: General purpose intelligent sensor interface

    NASA Technical Reports Server (NTRS)

    Mckee, James W.

    1988-01-01

    This final report describes the accomplishments of the General Purpose Intelligent Sensor Interface task of the Applications of Artificial Intelligence to Space Station grant for the period from October 1, 1987 through September 30, 1988. Portions of the First Biannual Report not revised will not be included but only referenced. The goal is to develop an intelligent sensor system that will simplify the design and development of expert systems using sensors of the physical phenomena as a source of data. This research will concentrate on the integration of image processing sensors and voice processing sensors with a computer designed for expert system development. The result of this research will be the design and documentation of a system in which the user will not need to be an expert in such areas as image processing algorithms, local area networks, image processor hardware selection or interfacing, television camera selection, voice recognition hardware selection, or analog signal processing. The user will be able to access data from video or voice sensors through standard LISP statements without any need to know about the sensor hardware or software.

  3. General-Purpose Heat Source: Research and development program: Cold-Process Verification Test Series

    SciTech Connect

    Reimus, M.A.H.; George, T.G.

    1996-06-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements. Because any space mission could experience a launch abort or return from orbit, the heat source must be designed and constructed to survive credible accident environments. Previous testing conducted in support of the Galileo and Ulysses missions documented the response of GPHSs and individual GPHS capsules fueled with {sup 238}UO{sub 2} ({sup 235}U-depleted) to a variety of explosive overpressure and impact events. In the early 1990s, Los Alamos National Laboratory (LANL) resumed fabrication of {sup 238}UO{sub 2} GPHS pellets. The Cold-Process Verification (CPV) Test Series was designed to compare the response of GPHS heat sources loaded with recently fabricated hot- and cold-pressed {sup 238}UO{sub 2} pellets to the response of urania pellets used in the Galileo and Ulysses performance tests. This report documents eleven bare-capsule impacts and one impact of a fully loaded GPHS module. All of the failures observed in the bare-clad impact tests were similar to failures observed in previous safety tests. No failures occurred in the module impact test.

  4. A general-purpose approach to computer-aided dynamic analysis of a flexible helicopter

    NASA Technical Reports Server (NTRS)

    Agrawal, Om P.

    1988-01-01

    A general purpose mathematical formulation is described for dynamic analysis of a helicopter consisting of flexible and/or rigid bodies that undergo large translations and rotations. Rigid body and elastic sets of generalized coordinates are used. The rigid body coordinates define the location and the orientation of a body coordinate frame (global frame) with respect to an inertial frame. The elastic coordinates are introduced using a finite element approach in order to model flexible components. The compatibility conditions between two adjacent elements in a flexible body are imposed using a Boolean matrix, whereas the compatibility conditions between two adjacent bodies are imposed using the Lagrange multiplier approach. Since the form of the constraint equations depends upon the type of kinematic joint and involves only the generalized coordinates of the two participating elements, then a library of constraint elements can be developed to impose the kinematic constraint in an automated fashion. For the body constraints, the Lagrange multipliers yield the reaction forces and torques of the bodies at the joints. The virtual work approach is used to derive the equations of motion, which are a system of differential and algebraic equations that are highly nonlinear. The formulation presented is general and is compared with hard-wired formulations commonly used in helicopter analysis.

  5. Production of general purpose heat source (GPHS) using advanced manufacturing methods

    NASA Astrophysics Data System (ADS)

    Miller, Roger G.

    1996-03-01

    Mankind will continue to explore the stars through the use of unmanned space craft until the technology and costs are compatible with sending travelers to the outer planets of our solar system and beyond. Unmanned probes of the present and future will be necessary to develop the necessary technologies and obtain information that will make this travel possible. Because of the significant costs incurred, the use of modern manufacturing technologies must be used to lower the investment needed even when shared by international partnerships. For over the last 30 years, radioisotopes have provided the heat from which electrical power is extracted. Electric power for future spacecraft will be provided by either Radioisotope Thermoelectric Generators (RTG), Radioisotopic Thermophotovoltaic systems (RTPV), radioisotope Stirling systems, or a combination of these. All of these systems will be thermally driven by General Purpose Heat Source (GPHS) fueled clad in some configuration. The GPHS clad contains a 238PuO2 pellet encapsulated in an iridium alloy container. Historically, the fabrication of the iridium alloy shells has been performed at EG&G Mound and Oak Ridge National Laboratory (ORNL), and girth welding at Westinghouse Savannah River Corporation (WSRC) and Los Alamos National Laboratory (LANL). This paper will describe the use of laser processing for welding, drilling, cutting, and machining with other manufacturing methods to reduce the costs of producing GPHS fueled clad components and compléted assemblies. Incorporation of new quality technologies will compliment these manufacturing methods to reduce cost.

  6. Dielectrophoresis-Based Sample Handling in General-Purpose Programmable Diagnostic Instruments

    PubMed Central

    Gascoyne, Peter R. C.; Vykoukal, Jody V.

    2009-01-01

    As the molecular origins of disease are better understood, the need for affordable, rapid, and automated technologies that enable microscale molecular diagnostics has become apparent. Widespread use of microsystems that perform sample preparation and molecular analysis could ensure that the benefits of new biomedical discoveries are realized by a maximum number of people, even those in environments lacking any infrastructure. While progress has been made in developing miniaturized diagnostic systems, samples are generally processed off-device using labor-intensive and time-consuming traditional sample preparation methods. We present the concept of an integrated programmable general-purpose sample analysis processor (GSAP) architecture where raw samples are routed to separation and analysis functional blocks contained within a single device. Several dielectrophoresis-based methods that could serve as the foundation for building GSAP functional blocks are reviewed including methods for cell and particle sorting, cell focusing, cell ac impedance analysis, cell lysis, and the manipulation of molecules and reagent droplets. PMID:19684877

  7. General-purpose heat source: Research and development program. Process evaluation, fuel pellet GF-47

    SciTech Connect

    Reimus, M.A.H.; George, T.G.

    1995-12-01

    The general-purpose heat source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements. Because the potential for a launch abort or return from orbit exists for any space mission, the heat source must be designed and constructed to survive credible accident environments. Previous testing conducted in support of the Galileo and Ulysses missions has documented the response of the GPHS heat source to a variety of fragment-impact, aging, atmospheric reentry, and Earth-impact conditions. Although heat sources for previous missions were fabricated by the Westinghouse Savannah River Company (WSRC), GPHS fueled-clads required for the Cassini mission to Saturn will be fabricated by Los Alamos National Laboratory (LANL). This evaluation is part of an ongoing program to determine the similarity of GPHS fueled clads and fuel pellets fabricated at LANL to those fabricated at WSRC. Pellet GF-47, which was fabricated at LANL in late 1994, was submitted for chemical and ceramographic analysis. The results indicated that the pellet had a chemical makeup and microstructure within the range of material fabricated at WSRC in the early 1980s.

  8. General-Purpose Heat Source development: Safety Verification Test Program. Bullet/fragment test series

    SciTech Connect

    George, T.G.; Tate, R.E.; Axler, K.M.

    1985-05-01

    The radioisotope thermoelectric generator (RTG) that will provide power for space missions contains 18 General-Purpose Heat Source (GPHS) modules. Each module contains four /sup 238/PuO/sub 2/-fueled clads and generates 250 W/sub (t)/. Because a launch-pad or post-launch explosion is always possible, we need to determine the ability of GPHS fueled clads within a module to survive fragment impact. The bullet/fragment test series, part of the Safety Verification Test Plan, was designed to provide information on clad response to impact by a compact, high-energy, aluminum-alloy fragment and to establish a threshold value of fragment energy required to breach the iridium cladding. Test results show that a velocity of 555 m/s (1820 ft/s) with an 18-g bullet is at or near the threshold value of fragment velocity that will cause a clad breach. Results also show that an exothermic Ir/Al reaction occurs if aluminum and hot iridium are in contact, a contact that is possible and most damaging to the clad within a narrow velocity range. The observed reactions between the iridium and the aluminum were studied in the laboratory and are reported in the Appendix.

  9. THERMAL TESTING OF 9977 GENERAL PURPOSE FISSILE PACKAGE USING A POOL FIRE

    SciTech Connect

    Smith, A; Cecil May, C; Lawrence Gelder, L; Glenn Abramczyk, G

    2007-02-15

    The 9977/9978 General Purpose Fissile Package (GPFP), has been designed as a cost-effective, user-friendly replacement for the DOT 6M Specification Package for transporting Plutonium and Uranium metals and oxides. To ensure the capability of the 9977 GPFP to withstand the regulatory crush test, urethane foam was chosen for the impact absorbing overpack. As part of the package development it was necessary to confirm that the urethane foam overpack would provide the required protection for the containment vessel during the thermal test portion of the Hypothetical Accident Conditions Sequential Tests. Development tests of early prototypes were performed, using a furnace. Based on the results of the development tests, detailed design enhancements were incorporated into the final design. Examples of the definitive 9977 design configuration were subjected to an all-engulfing pool fire test, as part of the HAC Sequential Tests, to support the application for certification. Testing has confirmed the package's ability to withstand the HAC thermal tests.

  10. Hydrophobically recovered and contact printed siloxane oligomers for general-purpose surface patterning.

    PubMed

    Kim, Ju-Han; Hwang, Hyun-Sik; Hahm, Si-Woo; Khang, Dahl-Young

    2010-08-03

    Hydrophobic recovery of elastomeric polydimethylsiloxane (PDMS) has been well-known in various fields, such as microcontact printing (microCP), microfluidics, and electric insulation, etc., which has been believed to be due to the transfer of out-diffused siloxane oligomers in PDMS. The recovery phenomenon has been used to control surface energy of a substrate, due partly to its nanoscale thickness. In this work, we extend the use of recovered oligomers to a general-purpose surface patterning process, in combination with both dry and wet pattern transfer processes. The out-diffused and transfer-printed oligomers play exactly the same role of "ink" in the conventional microCP; thus, the present method can be termed as "inkless" microcontact printing (ImicroCP). Also, the detailed nature of recovered oligomers has been investigated, and they are found to have a molecular weight approximately 10 times larger than that of pristine, uncured PDMS oligomers. And the molecular weight distribution is very broad with a polydispersity index of approximately 15. Then, we present and discuss various aspects of the ImicroCP process, such as pattern transfer onto substrate via wet or dry etching, effect of process variables on printing results, minimum feature size achieved by the technique, repeated printing with the same stamp, and the generation of more complex patterns from simpler ones by applying multiple ImicroCP.

  11. Advanced Ultrasonic Inspection Techniques for General Purpose Heat Source Fueled Clad Closure Welds

    SciTech Connect

    Moyer, M.W.

    2001-01-11

    A radioisotope thermoelectric generator is used to provide a power source for long-term deep space missions. This General Purpose Heat Source (GPHS) is fabricated using iridium clad vent sets to contain the plutonium oxide fuel pellets. Integrity of the closure weld is essential to ensure containment of the plutonium. The Oak Ridge Y-12 Plant took the lead role in developing the ultrasonic inspection for the closure weld and transferring the inspection to Los Alamos National Laboratory for use in fueled clad inspection for the Cassini mission. Initially only amplitude and time-of-flight data were recorded. However, a number of benign geometric conditions produced signals that were larger than the acceptance threshold. To identify these conditions, a B-scan inspection was developed that acquired full ultrasonic waveforms. Using a test protocol the B-scan inspection was able to identify benign conditions such as weld shield fusion and internal mismatch. Tangential radiography was used to confirm the ultrasonic results. All but two of 29 fueled clads for which ultrasonic B-scan data was evaluated appeared to have signals that could be attributed to benign geometric conditions. This report describes the ultrasonic inspection developed at Y-12 for the Cassini mission.

  12. General-Purpose Heat Source development: safety test program. Postimpact evaluation, Design Iteration Test 2

    SciTech Connect

    Schonfeld, F.W.; George, T.G.

    1984-06-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of /sup 238/PuO/sub 2/ decay to thermoelectric elements. Because of the inevitable return of certain missions, the heat source must be Designed and constructed to survive both re-entry and Earth impact. The Design Iteration Test (DIT) series is part of an ongoing test program. In the first Design Iteration Test (DIT-1), a full GPHS module ontaining four iridium-alloy capsules loaded with /sup 238/PuO/sub 2/ was impacted at 57 m/s and 930/sup 0/C. All four capsules survived and none was breached. The capsules used in DIT-1 were loaded and welded at Los Alamos. The second Design Iteration Test (DIT-2) also used a full GPHS module and was impacted at 58 m/s and 930/sup 0/C. The four iridium-alloy capsules used in this test were loaded and welded at the Savannah River Plant (SRP). Postimpact examination revealed that two capsules had survived and two capsules had breached; a small quantity (approx. = 50 ..mu..g) of /sup 238/PuO/sub 2/ was released from the breached capsules. Internal cracking similar to that observed in the DIT-1 capsules was evident in all four of the DIT-2 capsules. Postimpact analyses of the units are described with emphasis on weld structure and performance.

  13. General-Purpose Heat Source Development: Safety Verification Test Program. Flyer plate test series

    SciTech Connect

    Cull, T.A.; Pavone, D.

    1986-09-01

    The General-Purpose Heat Source (GPHS) is a modular component of a radioisotope thermoelectric generator (RTG) that will provide electric power for space missions. The initial RTG applications will be for the NASA Galileo and the ESA Ulysses missions. Each of the 18 GPHS modules in an RTG contains four /sup 238/PuO/sub 2/-fueled clads and generates 250 W/sub (t)/. A series of Safety Verification Tests (SVTs) has been conducted to assess the ability of the GPHS fueled clads to contain the plutonia in accident environments. Because a launch pad or postlaunch explosion of the Space Transportation System Vehicle (space shuttle) is one conceivable accident, the SVT plan included a series of tests to simulate the fragment environment that the RTG and GPHS modules would experience in such an event. These tests deal specifically with the flat-on collision of flyer-plate-type fragments with bare, simulant-fueled (depleted UO/sub 2/) clads. Results of these tests suggest that the fueled clad is only minimally breached by collision with 3.53-mm-thick flyer-plate-type fragments of space shuttle alloy at velocities up to 1170 m/s. However, collision of a 38.1-mm-thick plate with a bare GPHS clad, at a velocity of 270 m/s, results in a total release of fuel.

  14. Nondestructive inspection of General Purpose Heat Source (GPHS) fueled clad girth welds

    SciTech Connect

    Reimus, M. A. H.; George, T. G.; Lynch, C.; Padilla, M.; Moniz, P.; Guerrero, A.; Moyer, M. W.; Placr, A.

    1998-01-15

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements. The GPHS is fabricated using an iridium-alloy to contain the {sup 238}PuO{sub 2} fuel pellet. GPHS capsules will be utilized in the upcoming Cassini mission to explore Saturn and its moons. The physical integrity of the girth weld is important to mission safety and performance. Because past experience had revealed a potential for initiation of small cracks in the girth weld overlap zone, a nondestructive inspection of each capsule weld is required. An ultrasonic method was used to inspect the welds of capsules fabricated for the Galileo mission. The instrument, transducer, and method used were state of the art at the time (early 1980s). The ultrasonic instrumentation and methods used to inspect the Cassini GPHSs was significantly upgraded from those used for the Galileo mission. GPHSs that had ultrasonic reflectors in excess of the reject specification level were subsequently inspected with radiography to provide additional engineering data used to accept/reject the heat source. This paper describes the Galileo-era ultrasonic instrumentation and methods and the subsequent upgrades made to support testing of Cassini GPHSs. Also discussed is the data obtained from radiographic examination and correlation to ultrasonic examination results.

  15. Design evolution and verification of the general-purpose heat source

    SciTech Connect

    Schock, A

    1980-01-01

    The General-Purpose Heat Source (GPHS) is a radioisotope heat source for use in space power systems. It employs a modular design, to make it adaptable to a wide range of energy conversion systems and power levels. Each 250 W module is completely autonomous, with its own passive safety provisions to prevent fuel release under all abort modes, including atmospheric reentry and earth impact. Prior development tests had demonstrated good impact survival as long as the iridium fuel capsules retained their ductility. This requires high impact temperatures, typically above 900/sup 0/C and reasonably fine grain size, which in turn requires avoidance of excessive operating temperatures and reentry temperatures. These three requirements - on operating, reentry, and impact temperatures - are in mutual conflict, since thermal design changes to improve any one of these temperatures tend to worsen one or both of the others. This conflict creates a difficult design problem, which for a time threatened the success of the program. The present paper describes how this problem was overcome by successive design revisions, supplemented by thermal analyses and confirmatory vibration and impact tests; and how this may be achieved while raising the specific power of the GPHS to 83 W/lb, a 50% improvement over previously flown radioisotope heat sources.

  16. A general purpose model for the condensed phases of water: TIP4P/2005

    NASA Astrophysics Data System (ADS)

    Abascal, J. L. F.; Vega, C.

    2005-12-01

    A potential model intended to be a general purpose model for the condensed phases of water is presented. TIP4P/2005 is a rigid four site model which consists of three fixed point charges and one Lennard-Jones center. The parametrization has been based on a fit of the temperature of maximum density (indirectly estimated from the melting point of hexagonal ice), the stability of several ice polymorphs and other commonly used target quantities. The calculated properties include a variety of thermodynamic properties of the liquid and solid phases, the phase diagram involving condensed phases, properties at melting and vaporization, dielectric constant, pair distribution function, and self-diffusion coefficient. These properties cover a temperature range from 123to573K and pressures up to 40000bar. The model gives an impressive performance for this variety of properties and thermodynamic conditions. For example, it gives excellent predictions for the densities at 1bar with a maximum density at 278K and an averaged difference with experiment of 7×10-4g/cm3.

  17. General-purpose heat source developmet: Safety test program. Postimpact evaluation, design iteration test 4

    NASA Astrophysics Data System (ADS)

    George, T. G.; Schonfeld, F. W.

    1984-12-01

    The general-purpose heat source (GPHS) provides power for space missions by transmitting the heat of Pu-238 decay to thermoelectric elements. Because of the inevitable return of certain aborted missions, the heat source must be designed and constructed to survive both re-entry and Earth impact. The design iteration test (DIT) series is part of an ongoing test program. The fourth test (DIT-4) was designed to evaluate the effect on impact behavior of changing the procedure used at the mount facility (MF) to remove surface defects from drawn cups. The change involved switching from a manual abrasion technique to a motorized, rubber-bonded abrasive wheel. In DIT-4 a partial GPHS module containing two fueled clads (one cleaned manually, and one cleaned with an abrasive wheel) was impacted at a velocity of 58 m/s and a temperature of 930 C. Both capsules were severely deformed by the impact and contained large interal cracks. Although the manually cleaned capsule breached, the breaching crack was only 2 microns wide and released negligible amounts of fuel. There did not appear to be any correlation between cleaning method and capsule performance. Postimpact analyses of the DIT-4 test components are described with emphasis on microstructure and impact response.

  18. Explosion overpressure test series: General-Purpose Heat Source development: Safety Verification Test program

    SciTech Connect

    Cull, T.A.; George, T.G.; Pavone, D.

    1986-09-01

    The General-Purpose Heat Source (GPHS) is a modular, radioisotope heat source that will be used in radioisotope thermoelectric generators (RTGs) to supply electric power for space missions. The first two uses will be the NASA Galileo and the ESA Ulysses missions. The RTG for these missions will contain 18 GPHS modules, each of which contains four /sup 238/PuO/sub 2/-fueled clads and generates 250 W/sub (t)/. A series of Safety Verification Tests (SVTs) was conducted to assess the ability of the GPHS modules to contain the plutonia in accident environments. Because a launch pad or postlaunch explosion of the Space Transportation System vehicle (space shuttle) is a conceivable accident, the SVT plan included a series of tests that simulated the overpressure exposure the RTG and GPHS modules could experience in such an event. Results of these tests, in which we used depleted UO/sub 2/ as a fuel simulant, suggest that exposure to overpressures as high as 15.2 MPa (2200 psi), without subsequent impact, does not result in a release of fuel.

  19. Implementation and performance of a general purpose graphics processing unit in hyperspectral image analysis

    NASA Astrophysics Data System (ADS)

    van der Werff, H. M. A.; Bakker, W. H.

    2014-02-01

    A graphics processing unit (GPU) can perform massively parallel computations at relatively low cost. Software interfaces like NVIDIA CUDA allow for General Purpose computing on a GPU (GPGPU). Wrappers of the CUDA libraries for higher-level programming languages such as MATLAB and IDL allow its use in image processing. In this paper, we implement GPGPU in IDL with two distance measures frequently used in image classification, Euclidean distance and spectral angle, and apply these to hyperspectral imagery. First we vary the data volume of a synthetic dataset by changing the number of image pixels, spectral bands and classification endmembers to determine speed-up and to find the smallest data volume that would still benefit from using graphics hardware. Then we process real datasets that are too large to fit in the GPU memory, and study the effect of resulting extra data transfers on computing performance. We show that our GPU algorithms outperform the same algorithms for a central processor unit (CPU), that a significant speed-up can already be obtained on relatively small datasets, and that data transfers in large datasets do not significantly influence performance. Given that no specific knowledge on parallel computing is required for this implementation, remote sensing scientists should now be able to implement and use GPGPU for their data analysis.

  20. BCI2000: a general-purpose brain-computer interface (BCI) system.

    PubMed

    Schalk, Gerwin; McFarland, Dennis J; Hinterberger, Thilo; Birbaumer, Niels; Wolpaw, Jonathan R

    2004-06-01

    Many laboratories have begun to develop brain-computer interface (BCI) systems that provide communication and control capabilities to people with severe motor disabilities. Further progress and realization of practical applications depends on systematic evaluations and comparisons of different brain signals, recording methods, processing algorithms, output formats, and operating protocols. However, the typical BCI system is designed specifically for one particular BCI method and is, therefore, not suited to the systematic studies that are essential for continued progress. In response to this problem, we have developed a documented general-purpose BCI research and development platform called BCI2000. BCI2000 can incorporate alone or in combination any brain signals, signal processing methods, output devices, and operating protocols. This report is intended to describe to investigators, biomedical engineers, and computer scientists the concepts that the BC12000 system is based upon and gives examples of successful BCI implementations using this system. To date, we have used BCI2000 to create BCI systems for a variety of brain signals, processing methods, and applications. The data show that these systems function well in online operation and that BCI2000 satisfies the stringent real-time requirements of BCI systems. By substantially reducing labor and cost, BCI2000 facilitates the implementation of different BCI systems and other psychophysiological experiments. It is available with full documentation and free of charge for research or educational purposes and is currently being used in a variety of studies by many research groups.

  1. Environmental assessment of general-purpose heat source safety verification testing

    SciTech Connect

    1995-02-01

    This Environmental Assessment (EA) was prepared to identify and evaluate potential environmental, safety, and health impacts associated with the Proposed Action to test General-Purpose Heat Source (GPHS) Radioisotope Thermoelectric Generator (RTG) assemblies at the Sandia National Laboratories (SNL) 10,000-Foot Sled Track Facility, Albuquerque, New Mexico. RTGs are used to provide a reliable source of electrical power on board some spacecraft when solar power is inadequate during long duration space missions. These units are designed to convert heat from the natural decay of radioisotope fuel into electrical power. Impact test data are required to support DOE`s mission to provide radioisotope power systems to NASA and other user agencies. The proposed tests will expand the available safety database regarding RTG performance under postulated accident conditions. Direct observations and measurements of GPHS/RTG performance upon impact with hard, unyielding surfaces are required to verify model predictions and to ensure the continual evolution of the RTG designs that perform safely under varied accident environments. The Proposed Action is to conduct impact testing of RTG sections containing GPHS modules with simulated fuel. End-On and Side-On impact test series are planned.

  2. Application of NASA General-Purpose Solver to Large-Scale Computations in Aeroacoustics

    NASA Technical Reports Server (NTRS)

    Watson, Willie R.; Storaasli, Olaf O.

    2004-01-01

    Of several iterative and direct equation solvers evaluated previously for computations in aeroacoustics, the most promising was the NASA-developed General-Purpose Solver (winner of NASA's 1999 software of the year award). This paper presents detailed, single-processor statistics of the performance of this solver, which has been tailored and optimized for large-scale aeroacoustic computations. The statistics, compiled using an SGI ORIGIN 2000 computer with 12 Gb available memory (RAM) and eight available processors, are the central processing unit time, RAM requirements, and solution error. The equation solver is capable of solving 10 thousand complex unknowns in as little as 0.01 sec using 0.02 Gb RAM, and 8.4 million complex unknowns in slightly less than 3 hours using all 12 Gb. This latter solution is the largest aeroacoustics problem solved to date with this technique. The study was unable to detect any noticeable error in the solution, since noise levels predicted from these solution vectors are in excellent agreement with the noise levels computed from the exact solution. The equation solver provides a means for obtaining numerical solutions to aeroacoustics problems in three dimensions.

  3. Evaluation and characterization of General Purpose Heat Source girth welds for the Cassini mission

    SciTech Connect

    Lynch, C.M.; Moniz, P.F.; Reimus, M.A.H.

    1998-12-31

    General Purpose Heat Sources (GPHSs) are components of Radioisotopic thermoelectric Generators (RTGs) which provide electric power for deep space missions. Each GPHS consists of a {sup 238}Pu oxide ceramic pellet encapsulated in a welded iridium alloy shell which forms a protective barrier against the release of plutonia in the unlikely event of a launch-pad failure or reentry incident. GPHS fueled clad girth weld flaw detection was paramount to ensuring this safety function, and was accomplished using both destructive and non-destructive evaluation techniques. The first girth weld produced from each welding campaign was metallographically examined for flaws such as incomplete weld penetration, cracks, or porosity which would render a GPHS unacceptable for flight applications. After an acceptable example weld was produced, the subsequently welded heat sources were evaluated non-destructively for flaws using ultrasonic immersion testing. Selected heat sources which failed ultrasonic testing would be radiographed, and/or, destructively evaluated to further characterize and document anomalous indications. Metallography was also performed on impacted heat sources to determine the condition of the welds.

  4. deconSTRUCT: general purpose protein database search on the substructure level.

    PubMed

    Zhang, Zong Hong; Bharatham, Kavitha; Sherman, Westley A; Mihalek, Ivana

    2010-07-01

    deconSTRUCT webserver offers an interface to a protein database search engine, usable for a general purpose detection of similar protein (sub)structures. Initially, it deconstructs the query structure into its secondary structure elements (SSEs) and reassembles the match to the target by requiring a (tunable) degree of similarity in the direction and sequential order of SSEs. Hierarchical organization and judicious use of the information about protein structure enables deconSTRUCT to achieve the sensitivity and specificity of the established search engines at orders of magnitude increased speed, without tying up irretrievably the substructure information in the form of a hash. In a post-processing step, a match on the level of the backbone atoms is constructed. The results presented to the user consist of the list of the matched SSEs, the transformation matrix for rigid superposition of the structures and several ways of visualization, both downloadable and implemented as a web-browser plug-in. The server is available at http://epsf.bmad.bii.a-star.edu.sg/struct_server.html.

  5. Efficient reconstruction of biological networks via transitive reduction on general purpose graphics processors

    PubMed Central

    2012-01-01

    Background Techniques for reconstruction of biological networks which are based on perturbation experiments often predict direct interactions between nodes that do not exist. Transitive reduction removes such relations if they can be explained by an indirect path of influences. The existing algorithms for transitive reduction are sequential and might suffer from too long run times for large networks. They also exhibit the anomaly that some existing direct interactions are also removed. Results We develop efficient scalable parallel algorithms for transitive reduction on general purpose graphics processing units for both standard (unweighted) and weighted graphs. Edge weights are regarded as uncertainties of interactions. A direct interaction is removed only if there exists an indirect interaction path between the same nodes which is strictly more certain than the direct one. This is a refinement of the removal condition for the unweighted graphs and avoids to a great extent the erroneous elimination of direct edges. Conclusions Parallel implementations of these algorithms can achieve speed-ups of two orders of magnitude compared to their sequential counterparts. Our experiments show that: i) taking into account the edge weights improves the reconstruction quality compared to the unweighted case; ii) it is advantageous not to distinguish between positive and negative interactions since this lowers the complexity of the algorithms from NP-complete to polynomial without loss of quality. PMID:23110660

  6. A general purpose model for the condensed phases of water: TIP4P/2005.

    PubMed

    Abascal, J L F; Vega, C

    2005-12-15

    A potential model intended to be a general purpose model for the condensed phases of water is presented. TIP4P/2005 is a rigid four site model which consists of three fixed point charges and one Lennard-Jones center. The parametrization has been based on a fit of the temperature of maximum density (indirectly estimated from the melting point of hexagonal ice), the stability of several ice polymorphs and other commonly used target quantities. The calculated properties include a variety of thermodynamic properties of the liquid and solid phases, the phase diagram involving condensed phases, properties at melting and vaporization, dielectric constant, pair distribution function, and self-diffusion coefficient. These properties cover a temperature range from 123 to 573 K and pressures up to 40,000 bar. The model gives an impressive performance for this variety of properties and thermodynamic conditions. For example, it gives excellent predictions for the densities at 1 bar with a maximum density at 278 K and an averaged difference with experiment of 7 x 10(-4) g/cm3.

  7. Application of a Computerized General Purpose Information Management System (SELGEM) (SELf-GEnerating Master) to Medically Important Arthropods (Diptera: Culicidae).

    DTIC Science & Technology

    1981-08-01

    APPLICATION OF A COMPUTERIZED GENERAL PURPOSE INFORMATION MANAGEMENT SYSTEM (SELGEM) TO MEDICALLY IMPORTANT ARTHROPODS (DIPTERA: CULICIDAE) I’ Annual Report...Bailey. 1981. Application of a com- puterized information management system (SELGEM) to medically important arthropods (National Museum Mosquito

  8. A micron resolution optical scanner for characterization of silicon detectors

    NASA Astrophysics Data System (ADS)

    Shukla, R. A.; Dugad, S. R.; Garde, C. S.; Gopal, A. V.; Gupta, S. K.; Prabhu, S. S.

    2014-02-01

    The emergence of high position resolution (˜10 μm) silicon detectors in recent times have highlighted the urgent need for the development of new automated optical scanners of micron level resolution suited for characterizing microscopic features of these detectors. More specifically, for the newly developed silicon photo-multipliers (SiPM) that are compact, possessing excellent photon detection efficiency with gain comparable to photo-multiplier tube. In a short time, since their invention the SiPMs are already being widely used in several high-energy physics and astrophysics experiments as the photon readout element. The SiPM is a high quantum efficiency, multi-pixel photon counting detector with fast timing and high gain. The presence of a wide variety of photo sensitive silicon detectors with high spatial resolution requires their performance evaluation to be carried out by photon beams of very compact spot size. We have designed a high resolution optical scanner that provides a monochromatic focused beam on a target plane. The transverse size of the beam was measured by the knife-edge method to be 1.7 μm at 1 - σ level. Since the beam size was an order of magnitude smaller than the typical feature size of silicon detectors, this optical scanner can be used for selective excitation of these detectors. The design and operational details of the optical scanner, high precision programmed movement of target plane (0.1 μm) integrated with general purpose data acquisition system developed for recording static and transient response photo sensitive silicon detector are reported in this paper. Entire functionality of scanner is validated by using it for selective excitation of individual pixels in a SiPM and identifying response of active and dead regions within SiPM. Results from these studies are presented in this paper.

  9. A micron resolution optical scanner for characterization of silicon detectors

    SciTech Connect

    Shukla, R. A.; Dugad, S. R. Gopal, A. V.; Gupta, S. K.; Prabhu, S. S.; Garde, C. S.

    2014-02-15

    The emergence of high position resolution (∼10 μm) silicon detectors in recent times have highlighted the urgent need for the development of new automated optical scanners of micron level resolution suited for characterizing microscopic features of these detectors. More specifically, for the newly developed silicon photo-multipliers (SiPM) that are compact, possessing excellent photon detection efficiency with gain comparable to photo-multiplier tube. In a short time, since their invention the SiPMs are already being widely used in several high-energy physics and astrophysics experiments as the photon readout element. The SiPM is a high quantum efficiency, multi-pixel photon counting detector with fast timing and high gain. The presence of a wide variety of photo sensitive silicon detectors with high spatial resolution requires their performance evaluation to be carried out by photon beams of very compact spot size. We have designed a high resolution optical scanner that provides a monochromatic focused beam on a target plane. The transverse size of the beam was measured by the knife-edge method to be 1.7 μm at 1 − σ level. Since the beam size was an order of magnitude smaller than the typical feature size of silicon detectors, this optical scanner can be used for selective excitation of these detectors. The design and operational details of the optical scanner, high precision programmed movement of target plane (0.1 μm) integrated with general purpose data acquisition system developed for recording static and transient response photo sensitive silicon detector are reported in this paper. Entire functionality of scanner is validated by using it for selective excitation of individual pixels in a SiPM and identifying response of active and dead regions within SiPM. Results from these studies are presented in this paper.

  10. A micron resolution optical scanner for characterization of silicon detectors.

    PubMed

    Shukla, R A; Dugad, S R; Garde, C S; Gopal, A V; Gupta, S K; Prabhu, S S

    2014-02-01

    The emergence of high position resolution (∼10 μm) silicon detectors in recent times have highlighted the urgent need for the development of new automated optical scanners of micron level resolution suited for characterizing microscopic features of these detectors. More specifically, for the newly developed silicon photo-multipliers (SiPM) that are compact, possessing excellent photon detection efficiency with gain comparable to photo-multiplier tube. In a short time, since their invention the SiPMs are already being widely used in several high-energy physics and astrophysics experiments as the photon readout element. The SiPM is a high quantum efficiency, multi-pixel photon counting detector with fast timing and high gain. The presence of a wide variety of photo sensitive silicon detectors with high spatial resolution requires their performance evaluation to be carried out by photon beams of very compact spot size. We have designed a high resolution optical scanner that provides a monochromatic focused beam on a target plane. The transverse size of the beam was measured by the knife-edge method to be 1.7 μm at 1 - σ level. Since the beam size was an order of magnitude smaller than the typical feature size of silicon detectors, this optical scanner can be used for selective excitation of these detectors. The design and operational details of the optical scanner, high precision programmed movement of target plane (0.1 μm) integrated with general purpose data acquisition system developed for recording static and transient response photo sensitive silicon detector are reported in this paper. Entire functionality of scanner is validated by using it for selective excitation of individual pixels in a SiPM and identifying response of active and dead regions within SiPM. Results from these studies are presented in this paper.

  11. A General Purpose Feature Extractor for Light Detection and Ranging Data

    DTIC Science & Technology

    2010-11-17

    Similarly, the family of stochastic gradient descent (SGD) algorithms [15,16] and Gauss - Seidel relaxation [17,18] have runtimes that are directly...proposed method . The observation positions are indicated by the black triangle. Grey ellipses indicate 3δ uncertainties and numbers and letters are index of...detector for both 2D and 3D LIDAR data that is applicable to virtually any environment. Our method adapts classic feature detection methods from the image

  12. High-precision determination of iron oxidation state in silicate glasses using XANES

    SciTech Connect

    Cottrell, Elizabeth; Kelley, Katherine A.; Lanzirotti, Antonio; Fischer, Rebecca A.

    2009-11-04

    Fe K-edge X-ray absorption near-edge structure (XANES) and Moessbauer spectra were collected on natural basaltic glasses equilibrated over a range of oxygen fugacity (QFM - 3.5 to QFM + 4.5). The basalt compositions and fO{sub 2} conditions were chosen to bracket the natural range of redox conditions expected for basalts from mid-ocean ridge, ocean island, back-arc basin, and arc settings, in order to develop a high-precision calibration for the determination of Fe{sup 3+}/{Sigma}Fe in natural basalts. The pre-edge centroid energy, corresponding to the 1s {yields} 3d transition, was determined to be the most robust proxy for Fe oxidation state, affording significant advantages compared to the use of other spectral features. A second-order polynomial models the correlation between the centroid and Fe{sup 3+}/{Sigma}Fe, yielding a precision of {+-} 0.0045 in Fe{sup 3+}/{Sigma}Fe for glasses with Fe{sup 3+}/{Sigma}Fe > 8%, which is comparable to the precision of wet chemistry. This high precision relies on a Si (311) monochromator to better define the Fe{sup 2+} and Fe{sup 3+} transitions, accurate and robust modeling of the pre-edge feature, dense fO{sub 2}-coverage and compositional appropriateness of reference glasses, and application of a non-linear drift correction. Through re-analysis of the reference glasses across three synchrotron beam sessions, we show that the quoted precision can be achieved (i.e., analyses are reproducible) across multiple synchrotron beam sessions, even when spectral collection conditions (detector parameters or sample geometry) change. Rhyolitic glasses were also analyzed and yield a higher centroid energy at a given Fe{sup 3+}/{Sigma}Fe than basalts, implying that major variations in melt structure affect the relationship between centroid position and Fe{sup 3+}/{Sigma}Fe, and that separate calibrations are needed for the determination of oxidation state in basalts and rhyolites.

  13. A general purpose FASTBUS master (GPM) and memory module (DSM) for online applications

    SciTech Connect

    Muller, H.

    1986-02-01

    The GPM is a high performance Fastbus master/slave, driven by 68 000 (or optionally 68 020/68 881 processors). Developed for general purpose applications it will perform control, trigger and diagnostic functions in three different experiments at CERN (DELPHI, L3, VIRTUS). Commercially available as single-board Fastbus master/slave, the GPM is a cheap processor component which can be connected to the DSM Fastbus dual-slave memory to perform as a low-level trigger processor, event formatter or data-spy. The GPM supports interprocessor interrupts via a Fastbus CSR register, interrupts on events in the Fastbus (like SR), and external interrupts. The GPM is equipped with 1/2 Mbyte of RAM, 1/4 Mbyte of ROM and a 32 Kbyte Fastbus I/O buffer. Any Fastbus operation can be generated as mixture of autonomous block transfers and assembly-language instructions which are directly executed in Fastbus. Powerful diagnostics can be performed by the possibility to address its own slave-port, via the Fastbus and the applicability of the debugging monitor commands to individual Fastbus/68 000 cycles. A terminal and host connection is available. The DMA supported parallel port can be used for interface applications. For external interrupts and coaxial pulse I/O, a NIM pulse interface is available. The 2 Mbyte Dual Slave Memory (DSM) can be used either as a stand-alone Fastbus memory, or as a memory extension module of a GPM, with independent I/O on crate and cable segments. It supports linear or circular buffer concepts and can be used as a data-spy on5cable segments.

  14. A General-purpose Framework for Parallel Processing of Large-scale LiDAR Data

    NASA Astrophysics Data System (ADS)

    Li, Z.; Hodgson, M.; Li, W.

    2016-12-01

    Light detection and ranging (LiDAR) technologies have proven efficiency to quickly obtain very detailed Earth surface data for a large spatial extent. Such data is important for scientific discoveries such as Earth and ecological sciences and natural disasters and environmental applications. However, handling LiDAR data poses grand geoprocessing challenges due to data intensity and computational intensity. Previous studies received notable success on parallel processing of LiDAR data to these challenges. However, these studies either relied on high performance computers and specialized hardware (GPUs) or focused mostly on finding customized solutions for some specific algorithms. We developed a general-purpose scalable framework coupled with sophisticated data decomposition and parallelization strategy to efficiently handle big LiDAR data. Specifically, 1) a tile-based spatial index is proposed to manage big LiDAR data in the scalable and fault-tolerable Hadoop distributed file system, 2) two spatial decomposition techniques are developed to enable efficient parallelization of different types of LiDAR processing tasks, and 3) by coupling existing LiDAR processing tools with Hadoop, this framework is able to conduct a variety of LiDAR data processing tasks in parallel in a highly scalable distributed computing environment. The performance and scalability of the framework is evaluated with a series of experiments conducted on a real LiDAR dataset using a proof-of-concept prototype system. The results show that the proposed framework 1) is able to handle massive LiDAR data more efficiently than standalone tools; and 2) provides almost linear scalability in terms of either increased workload (data volume) or increased computing nodes with both spatial decomposition strategies. We believe that the proposed framework provides valuable references on developing a collaborative cyberinfrastructure for processing big earth science data in a highly scalable environment.

  15. Implementation of H.264 encoder on general-purpose processors with hyper-threading technology

    NASA Astrophysics Data System (ADS)

    Li, Eric Q.; Chen, Yen-Kuang

    2004-01-01

    H.264 is the emerging video coding standard, which aims at compressing high-quality video contents at low bit-rates. While its new encoding and decoding processes are similar to many previous standards, the new standard includes a number of new features and thus requires much more computation than most existing standards do. The complexity of H.264 standard poses a large amount of challenges to implementing the encoder/decoder in real-time via software on personal computers. Even after 2~3x performance improvement with media instruction on modern general-purpose processors and another 2~4x improvement from algorithmic optimization, the H.264 encoder is still too complicated to be implemented in real-time on a single processor. Based on the detailed analysis of the possibilities of parallelism in H.264 encoder, we proposed an efficient multithreading implementation of the H.264 video encoder. In order to guarantee enough concurrency of the whole system, an elaborate macroblock and inter-frame parallel scheduling scheme is presented. In addition, our macroblock-based multithreading scheme achieves almost no video quality losses in contrast to other parallelization schemes. Our results show that the multithreaded encoder can obtain another 3.96x speed-up on a four-processor system or 4.6x speed-up on a four-processor system with Hyper-Treading Technology. The techniques demonstrated in this work can be applied not only to H.264, but also to other video/image coding/decoding applications on personal computers.

  16. A general-purpose development environment for intelligent computer-aided training systems

    NASA Technical Reports Server (NTRS)

    Savely, Robert T.

    1990-01-01

    Space station training will be a major task, requiring the creation of large numbers of simulation-based training systems for crew, flight controllers, and ground-based support personnel. Given the long duration of space station missions and the large number of activities supported by the space station, the extension of space shuttle training methods to space station training may prove to be impractical. The application of artificial intelligence technology to simulation training can provide the ability to deliver individualized training to large numbers of personnel in a distributed workstation environment. The principal objective of this project is the creation of a software development environment which can be used to build intelligent training systems for procedural tasks associated with the operation of the space station. Current NASA Johnson Space Center projects and joint projects with other NASA operational centers will result in specific training systems for existing space shuttle crew, ground support personnel, and flight controller tasks. Concurrently with the creation of these systems, a general-purpose development environment for intelligent computer-aided training systems will be built. Such an environment would permit the rapid production, delivery, and evolution of training systems for space station crew, flight controllers, and other support personnel. The widespread use of such systems will serve to preserve task and training expertise, support the training of many personnel in a distributed manner, and ensure the uniformity and verifiability of training experiences. As a result, significant reductions in training costs can be realized while safety and the probability of mission success can be enhanced.

  17. A practical approach to evaluation of the germicidal efficiency of a general purpose military disinfectant.

    PubMed

    ROGERS, M R; MAHER, J T; KAPLAN, A M

    1961-11-01

    The bactericidal activity of a general purpose disinfectant consisting of 25% sodium-o-phenylphenolate and 75% sodium-4- and 6-chloro-2-phenylphenolate was evaluated by a simulated in-use, surface-square dilution method. Common floor (asphalt, rubber, and unglazed tiles) and wall (stainless steel tile, ceramic tile, and painted wood) surfaces of various porosities and compositions were selected to simulate actual-use conditions. The method used consisted of inoculating the surfaces of 1-in. square sections of floor and wall covering with a test organism, air-drying the inoculated surface, applying the disinfectant, allowing it to act for 10 min, and recovering the survivors by plating. Confirmatory results of the standard phenol coefficient and use-dilution tests indicated 700 ppm of the disinfectant to be a safe use concentration. The in-use surface-square dilution studies have shown that this is a more than adequate safe concentration for stainless steel, both glazed and unglazed ceramic tile, and nonwaxed surface of asphalt tile. However, concentrations ranging between 2,500 and 6,000 ppm for plastic-fortified rubber tile, 1,500 and 2,000 ppm for waxed asphalt tile, and 2,000 ppm for painted wood were required to achieve 99.9% reduction of either Salmonella choleraesuis or Salmonella schottmuelleri. These results indicate that a disinfectant concentration derived from the Association of Official Agricultural Chemists use-dilution test cannot always be relied upon to provide a dependable index to actual safe use-dilution when a disinfectant is supplied to certain wall or floor surfaces.

  18. Regioselectivity in azahydro[60]fullerene derivatives: application of general-purpose reactivity indicators.

    PubMed

    Contreras-Torres, Flavio F; Basiuk, Vladimir A; Basiuk, Elena V

    2008-09-04

    To attempt theoretical predictions of the regioselectivity pattern in molecules with multiple reactive sites, the energies of formation of all possible isomers are usually considered. This means that the computing becomes highly demanding if high theoretical levels are used. The study objective was to predict the regioselectivity in the reaction of hydrogen addition onto azahydro[60]fullerene C 59H n+1 N ( n = 0-4) systems using a new reactivity indicator termed general-purpose reactivity indicator, Xi Delta N

  19. A General-Purpose Optimization Engine for Multi-Disciplinary Design Applications

    NASA Technical Reports Server (NTRS)

    Patnaik, Surya N.; Hopkins, Dale A.; Berke, Laszlo

    1996-01-01

    A general purpose optimization tool for multidisciplinary applications, which in the literature is known as COMETBOARDS, is being developed at NASA Lewis Research Center. The modular organization of COMETBOARDS includes several analyzers and state-of-the-art optimization algorithms along with their cascading strategy. The code structure allows quick integration of new analyzers and optimizers. The COMETBOARDS code reads input information from a number of data files, formulates a design as a set of multidisciplinary nonlinear programming problems, and then solves the resulting problems. COMETBOARDS can be used to solve a large problem which can be defined through multiple disciplines, each of which can be further broken down into several subproblems. Alternatively, a small portion of a large problem can be optimized in an effort to improve an existing system. Some of the other unique features of COMETBOARDS include design variable formulation, constraint formulation, subproblem coupling strategy, global scaling technique, analysis approximation, use of either sequential or parallel computational modes, and so forth. The special features and unique strengths of COMETBOARDS assist convergence and reduce the amount of CPU time used to solve the difficult optimization problems of aerospace industries. COMETBOARDS has been successfully used to solve a number of problems, including structural design of space station components, design of nozzle components of an air-breathing engine, configuration design of subsonic and supersonic aircraft, mixed flow turbofan engines, wave rotor topped engines, and so forth. This paper introduces the COMETBOARDS design tool and its versatility, which is illustrated by citing examples from structures, aircraft design, and air-breathing propulsion engine design.

  20. Pelletization and encapsulation of general purpose heat source (GPHS) fueled clads for future space missions

    NASA Astrophysics Data System (ADS)

    Barklay, Chadwick D.; Miller, Roger G.; Malikh, Y.; Kalinovsky, A.; Aldoshin, A.

    1996-03-01

    Mankind must continue to explore the universe in order to gain a better understanding of how we relate to it and how we can best use its resources to our benefit. Because of the significant costs of this type of exploration, it can more effectively be accomplished through an international team effort. This unified effort must include the design, planning, and execution phases of future space missions, extending down to such activities as the processing, pelletization, and encapsulation of the fuel that will be used to support the spacecraft electrical power generation systems. Over the last 30 years, radioisotopes have provided heat from which electrical power is generated. For space missions, the isotope of choice has generally been 238PuO2, its long half-life making it ideal for supplying power to remote satellites and spacecraft like the Voyager, Pioneer, and Viking missions, as well as the recently launched Galileo and Ulysses missions, and the presently planned Cassini mission. Electric power for future space missions will be provided by either radioisotopic thermoelectric generators (RTG), radioisotope thermophotovoltaic systems (RTPV), radioisotope Stirling systems or a combination of these. However, all of the aforementioned systems will be thermally driven by General-Purpose Heat Source (GPHS) fueled clads in some configuration. Each GPHS fueled clad contains a 150-gram pellet of 238PuO2, and each pellet is encapsulated within an iridium-alloy shell. Historically, the fabrication of the iridium-alloy shells has been performed at EG&G Mound, and Oak Ridge National Laboratory, and the girth welding of the GPHS capsules has been performed at Westinghouse Savannah River Corporation, and Los Alamos National Laboratory. This paper describes a cost effective alternative method for the production of GPHS capsules. Fundamental considerations such as the potential production options, the associated support activities, and the methodology to transport the welded

  1. General-purpose heat source development: Extended series test program SRB fragment/fuselage tests

    NASA Astrophysics Data System (ADS)

    Cull, Theresa A.

    1989-06-01

    General-Purpose Heat Source radioisotope thermoelectric generators (GPHS-RTGs) will provide electrical power for the NASA Galileo and European Space Agency (ESA) Ulysses missions. Each GPHS-RTG comprises two major components: GPHS modules, which provide thermal energy, and a thermoelectric converter, which converts the thermal energy into electrical power. Each of the 18 GPHS modules in a GPHS-RTG contains four Pu-238O2-fueled capsules. LANL conducted a series of safety verification tests on the GPHS-RTG before the scheduled May 1986 launch of the Galileo spacecraft to assess the ability of the GPHS modules to contain plutonia in potential accident environments. As a result of the Challenger 51-L accident in January 1986, NASA postponed the launch of Galileo; the spacecraft launch vehicle was reconfigured and the spacecraft trajectory modified. These actions prompted NASA to reevaluate potential mission accidents and the extended series safety test program was initiated. This program included a series of solid rocket booster (SRB) fragment/fuselage tests that simulated the interaction of SRB fragments generated in an SRB motor case rupture (or resulting from a range safety officer SRB destruct action) with sections of the Shuttle Orbiter. The test data helped verify and refine the analytical models of the SRB fragment/fuselage interaction. The results showed that the fragment velocity decreased significantly (up to 40 percent) after penetrating the Orbiter section(s). The interactions also reduced, and in some cases eliminated, the original fragment rotational rate and direction and initiated rotation in other directions.

  2. Pelletization and encapsulation of general purpose heat source (GPHS) fueled clads for future space missions

    SciTech Connect

    Barklay, C.D.; Miller, R.G.; Malikh, Y.; Kalinovsky, A.; Aldoshin, A.

    1996-03-01

    Because of the significant costs of space exploration, it can more effectively be accomplished through an international team effort. This unified effort must include the design, planning, and execution phases of future space missions, extending down to such activities as the processing, pelletization, and encapsulation of the fuel that will be used to support the spacecraft electrical power generation systems. Over the last 30 years, radioisotopes have provided heat from which electrical power is generated. For space missions, the isotope of choice has generally been {sup 238}PuO{sub 2}, its long half-life making it ideal for supplying power to remote satellites and spacecraft like the Voyager, Pioneer, and Viking missions, as well as the recently launched Galileo and Ulysses missions, and the presently planned Cassini mission. Electric power for future space missions will be provided by either radioisotopic thermoelectric generators (RTG), radioisotope thermophotovoltaic systems (RTPV), radioisotope Stirling systems or a combination of these. However, all of the aforementioned systems will be thermally driven by General-Purpose Heat Source (GPHS) fueled clads in some configuration. Each GPHS fueled clad contains a 150-gram pellet of {sup 238}PuO{sub 2}, and each pellet is encapsulated within an iridium-alloy shell. Historically, the fabrication of the iridium-alloy shells has been performed at EG&G Mound, and Oak Ridge National Laboratory, and the girth welding of the GPHS capsules has been performed at Westinghouse Savannah River Corporation, and Los Alamos National Laboratory. This paper describes a cost effective alternative method for the production of GPHS capsules. Fundamental considerations such as the potential production options, the associated support activities, and the methodology to transport the welded fueled clads are discussed. (Abstract Truncated)

  3. Using general-purpose computing on graphics processing units (GPGPU) to accelerate the ordinary kriging algorithm

    NASA Astrophysics Data System (ADS)

    Gutiérrez de Ravé, E.; Jiménez-Hornero, F. J.; Ariza-Villaverde, A. B.; Gómez-López, J. M.

    2014-03-01

    Spatial interpolation methods have been applied to many disciplines, the ordinary kriging interpolation being one of the methods most frequently used. However, kriging comprises a computational cost that scales as the cube of the number of data points. Therefore, one most pressing problems in geostatistical simulations is that of developing methods that can reduce the computational time. Weights calculation and then the estimate for each unknown point is the most time-consuming step in ordinary kriging. This work investigates the potential reduction in execution time by selecting the suitable operations involved in this step to be parallelized by using general-purpose computing on graphics processing units (GPGPU) and Compute Unified Device Architecture (CUDA). This study has been performed by taking into account comparative studies between graphic and central processing units on two different machines, a personal computer (GPU, GeForce 9500, and CPU, AMD Athlon X2 4600) and a server (GPU, Tesla C1060, and CPU, Xeon 5600). In addition, two data types (float and double) have been considered in the executions. The experimental results indicate that parallel implementation of matrix inverse by using GPGPU and CUDA will be enough to reduce the execution time of weights calculation and estimation for each unknown point and, as a result, the global performance time of ordinary kriging. In addition, suitable array dimensions for using the available parallelized code have been determined for each case. Thus, it is possible to obtain relevant saved times compared to those resulting from considering wider parallelized extension. This fact demonstrates the convenience of carrying out this kind of study in other interpolation calculation methodologies using matrices.

  4. The PennBMBI: Design of a General Purpose Wireless Brain-Machine-Brain Interface System.

    PubMed

    Liu, Xilin; Zhang, Milin; Subei, Basheer; Richardson, Andrew G; Lucas, Timothy H; Van der Spiegel, Jan

    2015-04-01

    In this paper, a general purpose wireless Brain-Machine-Brain Interface (BMBI) system is presented. The system integrates four battery-powered wireless devices for the implementation of a closed-loop sensorimotor neural interface, including a neural signal analyzer, a neural stimulator, a body-area sensor node and a graphic user interface implemented on the PC end. The neural signal analyzer features a four channel analog front-end with configurable bandpass filter, gain stage, digitization resolution, and sampling rate. The target frequency band is configurable from EEG to single unit activity. A noise floor of 4.69 μVrms is achieved over a bandwidth from 0.05 Hz to 6 kHz. Digital filtering, neural feature extraction, spike detection, sensing-stimulating modulation, and compressed sensing measurement are realized in a central processing unit integrated in the analyzer. A flash memory card is also integrated in the analyzer. A 2-channel neural stimulator with a compliance voltage up to ± 12 V is included. The stimulator is capable of delivering unipolar or bipolar, charge-balanced current pulses with programmable pulse shape, amplitude, width, pulse train frequency and latency. A multi-functional sensor node, including an accelerometer, a temperature sensor, a flexiforce sensor and a general sensor extension port has been designed. A computer interface is designed to monitor, control and configure all aforementioned devices via a wireless link, according to a custom designed communication protocol. Wireless closed-loop operation between the sensory devices, neural stimulator, and neural signal analyzer can be configured. The proposed system was designed to link two sites in the brain, bridging the brain and external hardware, as well as creating new sensory and motor pathways for clinical practice. Bench test and in vivo experiments are performed to verify the functions and performances of the system.

  5. High-precision structure fabrication based on an etching resistance layer

    NASA Astrophysics Data System (ADS)

    Zhang, Man; Deng, Qiling; Shi, Lifang; Cao, Axiu; Pang, Hui; Liu, Xin; Wang, Jiazhou; Hu, Song

    2016-10-01

    The high-precision fabrication of micro-/nano-structure is a challenge. In this paper, we proposed a new fabrication method of high-precision structure based on an etching resistance layer. The high-precision features were fabricated by photolithography technique, followed by the etching process to transfer the features to the substrate. During this process, the etching uniformity and error lead to the feature distortion. We introduced an etching resistance layer between feature layer and substrate. The etching process will stop when arriving at the resistance layer. Due to the high precision of the plating film, the high-precision structure depth was achieved. In our experiment, we introduced aluminum trioxide as the etching resistance layer. The structures with low depth error of less than 5% were fabricated.

  6. Variable Conductance Heat Pipe Cooling of Stirling Convertor and General Purpose Heat Source

    NASA Technical Reports Server (NTRS)

    Tarau, Calin; Schwendeman, Carl; Anderson, William G.; Cornell, Peggy A.; Schifer, Nicholas A.

    2013-01-01

    In a Stirling Radioisotope Power System (RPS), heat must be continuously removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS at the cost of an early termination of the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) can be used to passively allow multiple stops and restarts of the Stirling convertor. In a previous NASA SBIR Program, Advanced Cooling Technologies, Inc. (ACT) developed a series of sodium VCHPs as backup cooling systems for Stirling RPS. The operation of these VCHPs was demonstrated using Stirling heater head simulators and GPHS simulators. In the most recent effort, a sodium VCHP with a stainless steel envelope was designed, fabricated and tested at NASA Glenn Research Center (GRC) with a Stirling convertor for two concepts; one for the Advanced Stirling Radioisotope Generator (ASRG) back up cooling system and one for the Long-lived Venus Lander thermal management system. The VCHP is designed to activate and remove heat from the stopped convertor at a 19 degC temperature increase from the nominal vapor temperature. The 19 degC temperature increase from nominal is low enough to avoid risking standard ASRG operation and spoiling of the Multi-Layer Insulation (MLI). In addition, the same backup cooling system can be applied to the Stirling convertor used for the refrigeration system of the Long-lived Venus Lander. The VCHP will allow the refrigeration system to: 1) rest during transit at a lower temperature than nominal; 2) pre-cool the modules to an even lower temperature before the entry in Venus atmosphere; 3) work at nominal temperature on Venus surface; 4) briefly stop multiple times on the Venus surface to allow scientific measurements. This paper presents the experimental

  7. Parallelized computation for computer simulation of electrocardiograms using personal computers with multi-core CPU and general-purpose GPU.

    PubMed

    Shen, Wenfeng; Wei, Daming; Xu, Weimin; Zhu, Xin; Yuan, Shizhong

    2010-10-01

    Biological computations like electrocardiological modelling and simulation usually require high-performance computing environments. This paper introduces an implementation of parallel computation for computer simulation of electrocardiograms (ECGs) in a personal computer environment with an Intel CPU of Core (TM) 2 Quad Q6600 and a GPU of Geforce 8800GT, with software support by OpenMP and CUDA. It was tested in three parallelization device setups: (a) a four-core CPU without a general-purpose GPU, (b) a general-purpose GPU plus 1 core of CPU, and (c) a four-core CPU plus a general-purpose GPU. To effectively take advantage of a multi-core CPU and a general-purpose GPU, an algorithm based on load-prediction dynamic scheduling was developed and applied to setting (c). In the simulation with 1600 time steps, the speedup of the parallel computation as compared to the serial computation was 3.9 in setting (a), 16.8 in setting (b), and 20.0 in setting (c). This study demonstrates that a current PC with a multi-core CPU and a general-purpose GPU provides a good environment for parallel computations in biological modelling and simulation studies. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  8. The NANOGrav Eleven-Year Data Set: High-precision timing of 48 Millisecond Pulsars

    NASA Astrophysics Data System (ADS)

    Nice, David J.; NANOGrav

    2017-01-01

    Gravitational waves from sources such as supermassive black hole binary systems perturb times-of-flight of signals traveling from pulsars to the Earth. The NANOGrav collaboration aims to measure these perturbations in high precision millisecond pulsar timing data and thus to directly detect gravitational waves and characterize the gravitational wave sources. By observing pulsars over time spans of many years, we are most sensitive to gravitational waves at nanohertz frequencies. This work is complimentary to ground based detectors such as LIGO, which are sensitive to gravitational waves with frequencies 10 orders of magnitude higher.In this presentation we describe the NANOGrav eleven-year data set. This includes pulsar time-of-arrival measurements from 48 millisecond pulsars made with the Arecibo Observatory (for pulsars with declinations between -1 and 39 degrees) and the Green Bank Telescope (for other pulsars, with two pulsars overlapping with Arecibo). The data set consists of more than 300,000 pulse time-of-arrival measurements made in nearly 7000 unique observations (a given pulsar observed with a given telescope receiver on a given day). In the best cases, measurement precision is better than 100 nanoseconds, and in nearly all cases it is better than 1 microsecond.All pulsars in our program are observed at intervals of 3 to 4 weeks. Observations use wideband data acquisition systems and are made at two receivers at widely separated frequencies at each epoch, allowing for characterization and mitigation of the effects of interstellar medium on the signal propagation. Observation of a large number of pulsars allows for searches for correlated perturbations among the pulsar signals, which is crucial for achieving high-significance detection of gravitational waves in the face of uncorrelated noise (from gravitational waves and rotation noise) in the individual pulsars. In addition, seven pulsars are observed at weekly intervals. This increases our sensitivity

  9. High-rate dead-time corrections in a general purpose digital pulse processing system.

    PubMed

    Abbene, Leonardo; Gerardi, Gaetano

    2015-09-01

    Dead-time losses are well recognized and studied drawbacks in counting and spectroscopic systems. In this work the abilities on dead-time correction of a real-time digital pulse processing (DPP) system for high-rate high-resolution radiation measurements are presented. The DPP system, through a fast and slow analysis of the output waveform from radiation detectors, is able to perform multi-parameter analysis (arrival time, pulse width, pulse height, pulse shape, etc.) at high input counting rates (ICRs), allowing accurate counting loss corrections even for variable or transient radiations. The fast analysis is used to obtain both the ICR and energy spectra with high throughput, while the slow analysis is used to obtain high-resolution energy spectra. A complete characterization of the counting capabilities, through both theoretical and experimental approaches, was performed. The dead-time modeling, the throughput curves, the experimental time-interval distributions (TIDs) and the counting uncertainty of the recorded events of both the fast and the slow channels, measured with a planar CdTe (cadmium telluride) detector, will be presented. The throughput formula of a series of two types of dead-times is also derived. The results of dead-time corrections, performed through different methods, will be reported and discussed, pointing out the error on ICR estimation and the simplicity of the procedure. Accurate ICR estimations (nonlinearity < 0.5%) were performed by using the time widths and the TIDs (using 10 ns time bin width) of the detected pulses up to 2.2 Mcps. The digital system allows, after a simple parameter setting, different and sophisticated procedures for dead-time correction, traditionally implemented in complex/dedicated systems and time-consuming set-ups.

  10. High-rate dead-time corrections in a general purpose digital pulse processing system

    PubMed Central

    Abbene, Leonardo; Gerardi, Gaetano

    2015-01-01

    Dead-time losses are well recognized and studied drawbacks in counting and spectroscopic systems. In this work the abilities on dead-time correction of a real-time digital pulse processing (DPP) system for high-rate high-resolution radiation measurements are presented. The DPP system, through a fast and slow analysis of the output waveform from radiation detectors, is able to perform multi-parameter analysis (arrival time, pulse width, pulse height, pulse shape, etc.) at high input counting rates (ICRs), allowing accurate counting loss corrections even for variable or transient radiations. The fast analysis is used to obtain both the ICR and energy spectra with high throughput, while the slow analysis is used to obtain high-resolution energy spectra. A complete characterization of the counting capabilities, through both theoretical and experimental approaches, was performed. The dead-time modeling, the throughput curves, the experimental time-interval distributions (TIDs) and the counting uncertainty of the recorded events of both the fast and the slow channels, measured with a planar CdTe (cadmium telluride) detector, will be presented. The throughput formula of a series of two types of dead-times is also derived. The results of dead-time corrections, performed through different methods, will be reported and discussed, pointing out the error on ICR estimation and the simplicity of the procedure. Accurate ICR estimations (nonlinearity < 0.5%) were performed by using the time widths and the TIDs (using 10 ns time bin width) of the detected pulses up to 2.2 Mcps. The digital system allows, after a simple parameter setting, different and sophisticated procedures for dead-time correction, traditionally implemented in complex/dedicated systems and time-consuming set-ups. PMID:26289270

  11. Achieving high precision photometry for transiting exoplanets with a low cost robotic DSLR-based imaging system

    NASA Astrophysics Data System (ADS)

    Guyon, Olivier; Martinache, Frantz

    2012-09-01

    We describe a low cost high precision photometric imaging system, which has been in robotic operation for one and half year on the Mauna Loa observatory (Hawaii). The system, which can be easily duplicated, is composed of commercially available components, offers a 150 sq deg field with two 70mm entrance apertures, and 6-band simultaneous photometry at a 0.01 Hz sampling. The detectors are low-cost commercial 3-color CMOS array, which we show is an attractive costeffective choice for high precision transit photometry. We describe the design of the system and show early results. A new data processing technique was developed to overcome pixelization and color errors. We show that this technique, which can also be applied on non-color imaging systems, essentially removes pixelization errors in the photometric signal, and we demonstrate on-sky photometric precision approaching fundamental error sources (photon noise and atmospheric scintillation). We conclude that our approach is ideally suited for exoplanet transit survey with multiple units. We show that in this scenario, the success metric is purely cost per etendue, which is at less than $10000s per square meter square degree for our system.

  12. Signal processing and general purpose data acquisition system for on-line tomographic measurements

    NASA Astrophysics Data System (ADS)

    Murari, A.; Martin, P.; Hemming, O.; Manduchi, G.; Marrelli, L.; Taliercio, C.; Hoffmann, A.

    1997-01-01

    New analog signal conditioning electronics and data acquisition systems have been developed for the soft x-ray and bolometric tomography diagnostic in the reverse field pinch experiment (RFX). For the soft x-ray detectors the analog signal processing includes a fully differential current to voltage conversion, with up to a 200 kHz bandwidth. For the bolometers, a 50 kHz carrier frequency amplifier allows a maximum bandwidth of 10 kHz. In both cases the analog signals are digitized with a 1 MHz sampling rate close to the diagnostic and are transmitted via a transparent asynchronous xmitter/receiver interface (TAXI) link to purpose built Versa Module Europa (VME) modules which perform data acquisition. A software library has been developed for data preprocessing and tomographic reconstruction. It has been written in C language and is self-contained, i.e., no additional mathematical library is required. The package is therefore platform-free: in particular it can perform online analysis in a real-time application, such as continuous display and feedback, and is portable for long duration fusion or other physical experiments. Due to the modular organization of the library, new preprocessing and analysis modules can be easily integrated in the environment. This software is implemented in RFX over three different platforms: open VMS, digital Unix, and VME 68040 CPU.

  13. BLASTbus electronics: general-purpose readout and control for balloon-borne experiments

    NASA Astrophysics Data System (ADS)

    Benton, S. J.; Ade, P. A.; Amiri, M.; Angilè, F. E.; Bock, J. J.; Bond, J. R.; Bryan, S. A.; Chiang, H. C.; Contaldi, C. R.; Crill, B. P.; Devlin, M. J.; Dober, B.; Doré, O. P.; Farhang, M.; Filippini, J. P.; Fissel, L. M.; Fraisse, A. A.; Fukui, Y.; Galitzki, N.; Gambrel, A. E.; Gandilo, N. N.; Golwala, S. R.; Gudmundsson, J. E.; Halpern, M.; Hasselfield, M.; Hilton, G. C.; Holmes, W. A.; Hristov, V. V.; Irwin, K. D.; Jones, W. C.; Kermish, Z. D.; Klein, J.; Korotkov, A. L.; Kuo, C. L.; MacTavish, C. J.; Mason, P. V.; Matthews, T. G.; Megerian, K. G.; Moncelsi, L.; Morford, T. A.; Mroczkowski, T. K.; Nagy, J. M.; Netterfield, C. B.; Novak, G.; Nutter, D.; O'Brient, R.; Ogburn, R. W.; Pascale, E.; Poidevin, F.; Rahlin, A. S.; Reintsema, C. D.; Ruhl, J. E.; Runyan, M. C.; Savini, G.; Scott, D.; Shariff, J. A.; Soler, J. D.; Thomas, N. E.; Trangsrud, A.; Truch, M. D.; Tucker, C. E.; Tucker, G. S.; Tucker, R. S.; Turner, A. D.; Ward-Thompson, D.; Weber, A. C.; Wiebe, D. V.; Young, E. Y.

    2014-07-01

    We present the second generation BLASTbus electronics. The primary purposes of this system are detector readout, attitude control, and cryogenic housekeeping, for balloon-borne telescopes. Readout of neutron transmutation doped germanium (NTD-Ge) bolometers requires low noise and parallel acquisition of hundreds of analog signals. Controlling a telescope's attitude requires the capability to interface to a wide variety of sensors and motors, and to use them together in a fast, closed loop. To achieve these different goals, the BLASTbus system employs a flexible motherboard-daughterboard architecture. The programmable motherboard features a digital signal processor (DSP) and field-programmable gate array (FPGA), as well as slots for three daughterboards. The daughterboards provide the interface to the outside world, with versions for analog to digital conversion, and optoisolated digital input/output. With the versatility afforded by this design, the BLASTbus also finds uses in cryogenic, thermometry, and power systems. For accurate timing control to tie everything together, the system operates in a fully synchronous manner. BLASTbus electronics have been successfully deployed to the South Pole, and own on stratospheric balloons.

  14. APL/JHU free flight tests of the general purpose heat source module. Testing: 5-7 March 1984

    NASA Astrophysics Data System (ADS)

    Baker, W. M., II

    The purpose of the test was to obtain statistical information on the dynamics of the General Purpose Heat Source (GPHS) module at terminal speeds. Models were designed to aerodynamically and dynamically represent the GPHS module. Normal and high speed photographic coverage documented the motion of the models. Test parameters and techniques for the free-spin tests are documented. Data analysis are not included.

  15. Study on manufacturing method of optical surface with high precision in angle and surface

    NASA Astrophysics Data System (ADS)

    Yu, Xin; Li, Xin; Yu, Ze; Zhao, Bin; Zhang, Xuebin; Sun, Lipeng; Tong, Yi

    2016-10-01

    This paper studied a manufacturing processing of optical surface with high precision in angel and surface. By theoretical analysis of the relationships between the angel precision and surface, the measurement conversion of the technical indicators, optical-cement method application, the optical-cement tooling design, the experiment has been finished successfully, the processing method has been verified, which can be also used in the manufacturing of the optical surface with similar high precision in angle and surface.

  16. Development of a high precision dosimetry system for the measurement of surface dose rate distribution for eye applicators

    SciTech Connect

    Eichmann, Marion; Fluehs, Dirk; Spaan, Bernhard

    2009-10-15

    Purpose: The therapeutic outcome of the therapy with ophthalmic applicators is highly dependent on the application of a sufficient dose to the tumor, whereas the dose applied to the surrounding tissue needs to be minimized. The goal for the newly developed apparatus described in this work is the determination of the individual applicator surface dose rate distribution with a high spatial resolution and a high precision in dose rate with respect to time and budget constraints especially important for clinical procedures. Inhomogeneities of the dose rate distribution can be detected and taken into consideration for the treatment planning. Methods: In order to achieve this, a dose rate profile as well as a surface profile of the applicator are measured and correlated with each other. An instrumental setup has been developed consisting of a plastic scintillator detector system and a newly designed apparatus for guiding the detector across the applicator surface at a constant small distance. It performs an angular movement of detector and applicator with high precision. Results: The measurements of surface dose rate distributions discussed in this work demonstrate the successful operation of the measuring setup. Measuring the surface dose rate distribution with a small distance between applicator and detector and with a high density of measuring points results in a complete and gapless coverage of the applicator surface, being capable of distinguishing small sized spots with high activities. The dosimetrical accuracy of the measurements and its analysis is sufficient (uncertainty in the dose rate in terms of absorbed dose to water is <7%), especially when taking the surgical techniques in positioning of the applicator on the eyeball into account. Conclusions: The method developed so far allows a fully automated quality assurance of eye applicators even under clinical conditions. These measurements provide the basis for future calculation of a full 3D dose rate

  17. A feasibility study of a prototype PET insert device to convert a general-purpose animal PET scanner to higher resolution.

    PubMed

    Wu, Heyu; Pal, Debashish; O'Sullivan, Joseph A; Tai, Yuan-Chuan

    2008-01-01

    We developed a prototype system to evaluate the feasibility of using a PET insert device to achieve higher resolution from a general-purpose animal PET scanner. The system consists of a high-resolution PET detector, a computer-controlled rotation stage, and a custom mounting plate. The detector consists of a cerium-doped lutetium oxyorthosilicate array (12 x 12 crystals, 0.8 x 1.66 x 3.75 mm(3) each) directly coupled to a position-sensitive photomultiplier tube (PS-PMT). The detector signals were fed into the scanner electronics to establish coincidences between the 2 systems. The detector was mounted to a rotation stage that is attached to the scanner via the custom mounting plate after removing the transmission source holder. The rotation stage was concentric with the center of the scanner. The angular offset of the insert detector was calibrated via optimizing point-source images. In all imaging experiments, coincidence data were collected from 9 angles to provide 180 degrees sampling. A (22)Na point source was imaged at different offsets from the center to characterize the in-plane resolution of the insert system. A (68)Ge point source was stepped across the axial field of view to measure the sensitivity of the system. A 23.2-g mouse was injected with 38.5 MBq of (18)F-fluoride and imaged at 3 h after injection for 2 h. The transverse image resolution of the PET insert device ranges from 1.1- to 1.4-mm full width at half maximum (FWHM) without correction for the point-source dimension. This corresponds to approximately 33% improvement over the resolution of the original scanner (1.7- to 1.8-mm FWHM) in 2 of the 3 directions. The sensitivity of the device is 0.064% at the center of the field, 46-fold lower than the sensitivity of an existing animal PET scanner. The mouse bone scan had improved image resolution using the PET insert device over that of the existing animal PET scanner alone. We have demonstrated the feasibility of using a high-resolution insert

  18. High-precision B(E2) measurements of semi-magic 58,60,62,64Ni by Coulomb excitation

    SciTech Connect

    Allmond, James M; Brown, Alex; Stuchbery, Andrew E; Galindo-Uribarri, Alfredo {nmn}; Padilla-Rodal, Elizabeth; Radford, David C; Batchelder, J. C.; Howard, Meredith E; Liang, J Felix; Manning, Brett M; Varner Jr, Robert L; Yu, Chang-Hong

    2014-01-01

    High-precision reduced electric-quadrupole transition probabilities B(E2) have been measured from single-step Coulomb excitation of semi-magic 58,60,62,64 Ni (Z = 28) beams at 1.8 MeV per nucleon on a natural carbon target. The energy loss of the nickel beams through the carbon target were directly measured with a zero-degree Bragg detector and the absolute B(E2) values were normalized by Rutherford scattering. The B(E2) values disagree with recent lifetime studies that employed the Doppler-shift attenuation method. The present high-precision B(E2) values reveal an asymmetry about 62 Ni, midshell between N = 28 and 40, with larger values towards 56 Ni (Z = N = 28). The experimental B(E2) values are compared with shell-model calculations in the full pf model space and the results indicate a soft 56 Ni core.

  19. The DØ detector

    NASA Astrophysics Data System (ADS)

    Abachi, S.; Abolins, M.; Acharya, B. S.; Adam, I.; Ahn, S.; Aihara, H.; Alvarez, G.; Alves, G. A.; Amos, N.; Anderson, W.; Antipov, Yu.; Aronson, S. H.; Astur, R.; Avery, R. E.; Baden, A.; Balderston, J.; Baldin, B.; Bantly, J.; Barasch, E.; Bartlett, J. F.; Bazizi, K.; Behnke, T.; Bezzubov, V.; Bhat, P. C.; Blazey, G.; Blessing, S.; Boehnlein, A.; Borcherding, F.; Borders, J.; Bozko, N.; Brandt, A.; Brock, R.; Bross, A.; Buchholz, D.; Burtovoy, V.; Butler, J. M.; Callot, O.; Chakraborty, D.; Chekulaev, S.; Chen, J.; Chen, L.-P.; Chen, W.; Choudhary, B. C.; Christenson, J. H.; Claes, D.; Clark, A. R.; Cobau, W. G.; Cochran, J.; Cooper, W. E.; Cretsinger, C.; Cullen-Vidal, D.; Cummings, M.; Cutts, D.; Dahl, O. I.; Daniels, B.; De, K.; Demarteau, M.; Denisenko, K.; Denisenko, N.; Denisov, D.; Denisov, S.; Dharmaratna, W.; Diehl, H. T.; Diesburg, M.; Dixon, R.; Draper, P.; Ducros, Y.; Durston-Johnson, S.; Eartly, D.; Eberhard, P. H.; Edmunds, D.; Efimov, A.; Ellison, J.; Elvira, V. D.; Engelmann, R.; Eroshin, O.; Evdokimov, V.; Fahey, S.; Fanourakis, G.; Fatyga, M.; Featherly, J.; Feher, S.; Fein, D.; Ferbel, T.; Finley, D.; Finocchiaro, G.; Fisk, H. E.; Flattum, E.; Forden, G. E.; Fortner, M.; Franzini, P.; Fuess, S.; Gallas, E.; Gao, C. S.; Geld, T. L.; Genser, K.; Gerber, C. E.; Gibbard, B.; Glebov, V.; Glicenstein, J. F.; Gobbi, B.; Goforth, M.; Good, M. L.; Goozen, F.; Gordon, H.; Graf, N.; Grannis, P. D.; Green, D. R.; Green, J.; Greenlee, H.; Grossman, N.; Grudberg, P.; Guida, J. A.; Guida, J. M.; Guryn, W.; Hadley, N. J.; Haggerty, H.; Hagopian, S.; Hagopian, V.; Hall, R. E.; Hansen, S.; Hauptman, J.; Hedin, D.; Heinson, A. P.; Heintz, U.; Heuring, T.; Hirosky, R.; Hodel, K.; Hoftun, J. S.; Hubbard, J. R.; Huehn, T.; Huson, R.; Igarashi, S.; Ito, A. S.; James, E.; Jiang, J.; Johns, K.; Johnson, C. R.; Johnson, M.; Jonckheere, A.; Jones, M.; Jöstlein, H.; Jung, C. K.; Kahn, S.; Kanekal, S.; Kernan, A.; Kerth, L.; Kirunin, A.; Klatchko, A.; Klima, B.; Klochkov, B.; Klopfenstein, C.; Klyukhin, V.; Kochetkov, V.; Kohli, J. M.; Kononenko, W.; Kotcher, J.; Kotov, I.; Kourlas, J.; Kozelov, A.; Kozlovsky, E.; Krafczyk, G.; Krempetz, K.; Krishnaswamy, M. R.; Kroon, P.; Krzywdzinski, S.; Kunori, S.; Lami, S.; Landsberg, G.; Lanou, R. E.; Laurens, P.; Lee-Franzini, J.; Li, J.; Li, R.; Li-Demarteau, Q. Z.; Lima, J. G. R.; Linn, S. L.; Linnemann, J.; Lipton, R.; Liu, Y.-C.; Lloyd-Owen, D.; Lobkowicz, F.; Loken, S. C.; Lokos, S.; Lueking, L.; Maciel, A. K. A.; Madaras, R. J.; Madden, R.; Malamud, E.; Mangeot, Ph.; Manning, I.; Mansoulié, B.; Manzella, V.; Mao, H.-S.; Marcin, M.; Markosky, L.; Marshall, T.; Martin, H. J.; Martin, M. I.; Martin, P. S.; Marx, M.; May, B.; Mayorov, A.; McCarthy, R.; McKinley, J.; Mendoza, D.; Meng, X.-C.; Merritt, K. W.; Milder, A.; Mincer, A.; Mondal, N. K.; Montag, M.; Mooney, P.; Mudan, M.; Mulholland, G. T.; Murphy, C.; Murphy, C. T.; Nang, F.; Narain, M.; Narasimham, V. S.; Neal, H. A.; Nemethy, P.; Nešić, D.; Ng, K. K.; Norman, D.; Oesch, L.; Oguri, V.; Oltman, E.; Oshima, N.; Owen, D.; Pang, M.; Para, A.; Park, C. H.; Partridge, R.; Paterno, M.; Peryshkin, A.; Peters, M.; Pi, B.; Piekarz, H.; Pischalnikov, Yu.; Pizzuto, D.; Pluquet, A.; Podstavkov, V.; Pope, B. G.; Prosper, H. B.; Protopopescu, S.; Que, Y.-K.; Quintas, P. Z.; Rahal-Callot, G.; Raja, R.; Rajagopalan, S.; Rao, M. V. S.; Rasmussen, L.; Read, A. L.; Regan, T.; Repond, S.; Riadovikov, V.; Rijssenbeek, M.; Roe, N. A.; Rubinov, P.; Rutherfoord, J.; Santoro, A.; Sawyer, L.; Schamberger, R. D.; Sculli, J.; Selove, W.; Shea, M.; Shkurenkov, A.; Shupe, M.; Singh, J. B.; Sirotenko, V.; Smart, W.; Smith, A.; Smith, D.; Smith, R. P.; Snow, G. R.; Snyder, S.; Sosebee, M.; Souza, M.; Spadafora, A. L.; Stampke, S.; Stephens, R.; Stevenson, M. L.; Stewart, D.; Stocker, F.; Stoyanova, D.; Stredde, H.; Streets, K.; Strovink, M.; Suhanov, A.; Taketani, A.; Tartaglia, M.; Taylor, J. D.; Teiger, J.; Theodosiou, G.; Thompson, J.; Tisserant, S.; Trippe, T. G.; Tuts, P. M.; Van Berg, R.; Vaz, M.; Vishwanath, P. R.; Volkov, A.; Vorobiev, A.; Wahl, H. D.; Wang, D.-C.; Wang, L.-Z.; Weerts, H.; Wenzel, W. A.; White, A.; White, J. T.; Wightman, J.; Willis, S.; Wimpenny, S. J.; Wolf, Z.; Womersley, J.; Wood, D. R.; Xia, Y.; Xiao, D.; Xie, P.; Xu, H.; Yamada, R.; Yamin, P.; Yanagisawa, C.; Yang, J.; Yang, M.-J.; Yoshikawa, C.; Youssef, S.; Yu, J.; Zeller, R.; Zhang, S.; Zhou, Y. H.; Zhu, Q.; Zhu, Y.-S.; Zieminska, D.; Zieminski, A.; Zinchenko, A.; Zylberstejn, A.; DØ Collaboration

    1994-01-01

    The DØ detector is a large general purpose detector for the study of short-distance phenomena in high energy antiproton-proton collisions, now in operation at the Fermilab Tevatron collider. The detector focusses upon the detection of electrons, muons, jets and missing transverse momentum. We describe the design and performance of the major elements of the detector, including the tracking chambers, transition radiation detector, liquid argon calorimetry and muon detection. The associated electronics, triggering systems and data acquisition systems are presented. The global mechanical, high voltage, and experiment monitoring and control systems which support the detector are described. We also discuss the design and implementation of software and software support systems that are specific to DØ.

  20. APL/JHU free flight tests of the General Purpose Heat Source module. Testing: 5-7 March 1984

    SciTech Connect

    Baker, W.M. II

    1984-01-01

    Purpose of the test was to obtain statistical information on the dynamics of the General Purpose Heat Source (GPHS) module at terminal speeds. Models were designed to aerodynamically and dynamically represent the GPHS module. Normal and high speed photographic coverage documented the motion of the models. This report documents test parameters and techniques for the free-spin tests. It does not include data analysis.

  1. Quality of healthcare websites: A comparison of a general-purpose vs. domain-specific search engine.

    PubMed

    Abraham, Joanna; Reddy, Madhu

    2007-10-11

    In a pilot study, we had five typical Internet users evaluate the quality of health websites returned by a general-purpose search engine (Google) and a healthcare-specific search engine (Healthfinder). The evaluators used a quality criteria developed by Mitretek/Health Information Technology Institute. Although both search engines provided high quality health websites, we found some important differences between the two types of search engines.

  2. Ultra-fast silicon detectors

    NASA Astrophysics Data System (ADS)

    Sadrozinski, H. F.-W.; Ely, S.; Fadeyev, V.; Galloway, Z.; Ngo, J.; Parker, C.; Petersen, B.; Seiden, A.; Zatserklyaniy, A.; Cartiglia, N.; Marchetto, F.; Bruzzi, M.; Mori, R.; Scaringella, M.; Vinattieri, A.

    2013-12-01

    We propose to develop a fast, thin silicon sensor with gain capable to concurrently measure with high precision the space (∼10 μm) and time (∼10 ps) coordinates of a particle. This will open up new application of silicon detector systems in many fields. Our analysis of detector properties indicates that it is possible to improve the timing characteristics of silicon-based tracking sensors, which already have sufficient position resolution, to achieve four-dimensional high-precision measurements. The basic sensor characteristics and the expected performance are listed, the wide field of applications are mentioned and the required R&D topics are discussed.

  3. Research on high-precision hole measurement based on robot vision method

    NASA Astrophysics Data System (ADS)

    Song, Li-mei; Li, Da-peng; Qin, Ming-cui; Li, Zong-yan; Chang, Yu-lan; Xi, Jiang-tao

    2014-09-01

    A high-precision vision detection and measurement system using mobile robot is established for the industry field detection of motorcycle frame hole and its diameter measurement. The robot path planning method is researched, and the non-contact measurement method with high precision based on visual digital image edge extraction and hole spatial circle fitting is presented. The Canny operator is used to extract the edge of captured image, the Lagrange interpolation algorithm is utilized to determine the missing image edge points and calculate the centroid, and the least squares fitting method is adopted to fit the image edge points. Experimental results show that the system can be used for the high-precision real-time measurement of hole on motorcycle frame. The absolute standard deviation of the proposed method is 0.026 7 mm. The proposed method can not only improve the measurement speed and precision, but also reduce the measurement error.

  4. High-Precision Registration of Point Clouds Based on Sphere Feature Constraints.

    PubMed

    Huang, Junhui; Wang, Zhao; Gao, Jianmin; Huang, Youping; Towers, David Peter

    2016-12-30

    Point cloud registration is a key process in multi-view 3D measurements. Its precision affects the measurement precision directly. However, in the case of the point clouds with non-overlapping areas or curvature invariant surface, it is difficult to achieve a high precision. A high precision registration method based on sphere feature constraint is presented to overcome the difficulty in the paper. Some known sphere features with constraints are used to construct virtual overlapping areas. The virtual overlapping areas provide more accurate corresponding point pairs and reduce the influence of noise. Then the transformation parameters between the registered point clouds are solved by an optimization method with weight function. In that case, the impact of large noise in point clouds can be reduced and a high precision registration is achieved. Simulation and experiments validate the proposed method.

  5. High-Precision Registration of Point Clouds Based on Sphere Feature Constraints

    PubMed Central

    Huang, Junhui; Wang, Zhao; Gao, Jianmin; Huang, Youping; Towers, David Peter

    2016-01-01

    Point cloud registration is a key process in multi-view 3D measurements. Its precision affects the measurement precision directly. However, in the case of the point clouds with non-overlapping areas or curvature invariant surface, it is difficult to achieve a high precision. A high precision registration method based on sphere feature constraint is presented to overcome the difficulty in the paper. Some known sphere features with constraints are used to construct virtual overlapping areas. The virtual overlapping areas provide more accurate corresponding point pairs and reduce the influence of noise. Then the transformation parameters between the registered point clouds are solved by an optimization method with weight function. In that case, the impact of large noise in point clouds can be reduced and a high precision registration is achieved. Simulation and experiments validate the proposed method. PMID:28042846

  6. Fabrication and Assembly of High-Precision Hinge and Latch Joints for Deployable Optical Instruments

    NASA Technical Reports Server (NTRS)

    Phelps, James E.

    1999-01-01

    Descriptions are presented of high-precision hinge and latch joints that have been co-developed, for application to deployable optical instruments, by NASA Langley Research Center and Nyma/ADF. Page-sized versions of engineering drawings are included in two appendices to describe all mechanical components of both joints. Procedures for assembling the mechanical components of both joints are also presented. The information herein is intended to facilitate the fabrication and assembly of the high-precision hinge and latch joints, and enable the incorporation of these joints into the design of deployable optical instrument systems.

  7. Construction of a versatile high precision ambient ionization source for direct analysis and imaging.

    PubMed

    Sampson, Jason S; Hawkridge, Adam M; Muddiman, David C

    2008-10-01

    The design and construction of a high precision ambient ionization source matrix-assisted laser desorption electrospray ionization (MALDESI) are described in full detail, including a complete parts list. The computer controlled high precision motion control system and high repetition rate Explorer laser are demonstrated during MALDESI-FT-ICR analysis of peptides and proteins ranging from 1 to 17 kDa. The high stability ionization source platform described herein demonstrates both the advantages of the new MALDESI source and versatility for application to numerous desorption and ionization techniques.

  8. High precision NC lathe feeding system rigid-flexible coupling model reduction technology

    NASA Astrophysics Data System (ADS)

    Xuan, He; Hua, Qingsong; Cheng, Lianjun; Zhang, Hongxin; Zhao, Qinghai; Mao, Xinkai

    2017-08-01

    This paper proposes the use of dynamic substructure method of reduction of order to achieve effective reduction of feed system for high precision NC lathe feeding system rigid-flexible coupling model, namely the use of ADAMS to establish the rigid flexible coupling simulation model of high precision NC lathe, and then the vibration simulation of the period by using the FD 3D damper is very effective for feed system of bolt connection reduction of multi degree of freedom model. The vibration simulation calculation is more accurate, more quickly.

  9. Machine vision for high-precision volume measurement applied to levitated containerless material processing

    SciTech Connect

    Bradshaw, R.C.; Schmidt, D.P.; Rogers, J.R.; Kelton, K.F.; Hyers, R.W.

    2005-12-15

    By combining the best practices in optical dilatometry with numerical methods, a high-speed and high-precision technique has been developed to measure the volume of levitated, containerlessly processed samples with subpixel resolution. Containerless processing provides the ability to study highly reactive materials without the possibility of contamination affecting thermophysical properties. Levitation is a common technique used to isolate a sample as it is being processed. Noncontact optical measurement of thermophysical properties is very important as traditional measuring methods cannot be used. Modern, digitally recorded images require advanced numerical routines to recover the subpixel locations of sample edges and, in turn, produce high-precision measurements.

  10. A high precision attitude determination and control system for the UYS-1 nanosatellite

    NASA Astrophysics Data System (ADS)

    Chaurais, J. R.; Ferreira, H. C.; Ishihara, J. Y.; Borges, R. A.; Kulabukhov, A. M.; Larin, V. A.; Belikov, V. V.

    This paper presents the design of a high precision attitude determination and control system for the UYS-1 Ukrainian nanosatellite. Its main task is the 3-axis stabilization with less than 0.5° angle errors, so the satellite may take high precision photos of Earth's surface. To accomplish this task, this system comprises a star tracker and three reaction wheels. To avoid external disturbances and actuators faults, a PD-type and a PID-type robust controllers are simulated and the results are compared to an empirically adjusted PD controller.

  11. High-precision self-adaptive phase-calibration method for wavelength-tuning interferometry

    NASA Astrophysics Data System (ADS)

    Zhu, Xueliang; Zhao, Huiying; Dong, Longchao; Wang, Hongjun; Liu, Bingcai; Yuan, Daocheng; Tian, Ailing; Wang, Fangjie; Zhang, Chupeng; Ban, Xinxing

    2017-03-01

    We introduce a high-precision self-adaptive phase-calibration method for performing wavelength-tuning interferometry. Our method is insensitive to the nonlinearity of the phase shifter, even under random control. Intensity errors derived from laser voltage changes can be restrained by adopting this approach. Furthermore, this method can effectively overcome the influences from the background and modulation intensities in the interferogram, regardless of the phase structure. Numerical simulations and experiments are implemented to verify the validity of this high-precision calibration method.

  12. Towards high precision measurements of nuclear g-factors for the Be isotopes

    NASA Astrophysics Data System (ADS)

    Takamine, A.; Wada, M.; Okada, K.; Ito, Y.; Schury, P.; Arai, F.; Katayama, I.; Imamura, K.; Ichikawa, Y.; Ueno, H.; Wollnik, H.; Schuessler, H. A.

    2016-06-01

    We describe the present status of future high-precision measurements of nuclear g-factors utilizing laser-microwave double and laser-microwave-rf triple resonance methods for online-trapped, laser-cooled radioactive beryllium isotope ions. These methods have applicability to other suitably chosen isotopes and for beryllium show promise in deducing the hyperfine anomaly of 11Be with a sufficiently high precision to study the nuclear magnetization distribution of this one-neutron halo nucleus in a nuclear-model-independent manner.

  13. Research on high-precision laser displacement sensor-based error compensation model

    NASA Astrophysics Data System (ADS)

    Zhang, Zhifeng; Zhai, Yusheng; Su, Zhan; Qiao, Lin; Tang, Yiming; Wang, Xinjie; Su, Yuling; Song, Zhijun

    2015-08-01

    The triangulation measurement is a kind of active vision measurement. The laser triangulation displacement is widely used with advantages of non-contact, high precision, high sensitivity. The measuring error will increase with the nonlinear and noise disturbance when sensors work in large distance. The paper introduces the principle of laser triangulation measurement and analyzes the measuring error and establishes the compensation error. Spot centroid is extracted with digital image processing technology to increase noise-signal ratio. Results of simulation and experiment show the method can meet requirement of large distance and high precision.

  14. Reliable and integrated technique for determining resonant frequency in radio frequency resonators. Application to a high-precision resonant cavity-based displacement sensor.

    PubMed

    Jauregui, Rigoberto; Asua, Estibaliz; Portilla, Joaquin; Etxebarria, Victor

    2015-03-01

    This paper presents a reliable and integrated technique for determining the resonant frequency of radio frequency resonators, which can be of interest for different purposes. The approach uses a heterodyne scheme as phase detector coupled to a voltage-controlled oscillator. The system seeks the oscillator frequency that produces a phase null in the resonator, which corresponds to the resonant frequency. A complete explanation of the technique to determine the resonant frequency is presented and experimentally tested. The method has been applied to a high-precision displacement sensor based on resonant cavity, obtaining a theoretical nanometric precision.

  15. General purpose rocket furnace

    NASA Technical Reports Server (NTRS)

    Aldrich, B. R.; Whitt, W. D. (Inventor)

    1979-01-01

    A multipurpose furnace for space vehicles used for material processing experiments in an outer space environment is described. The furnace contains three separate cavities designed to process samples of the widest possible range of materials and thermal requirements. Each cavity contains three heating elements capable of independent function under the direction of an automatic and programmable control system. A heat removable mechanism is also provided for each cavity which operates in conjunction with the control system for establishing an isothermally heated cavity or a wide range of thermal gradients and cool down rates. A monitoring system compatible with the rocket telemetry provides furnace performance and sample growth rate data throughout the processing cycle.

  16. General-purpose heat source project and space nuclear safety and fuels program. Progress reportt, January 1980

    SciTech Connect

    Maraman, W.J.

    1980-04-01

    This formal monthly report covers the studies related to the use of /sup 238/PuO/sub 2/ in radioisotopic power systems carried out for the Advanced Nuclear Systems and Projects Division of the Los Alamos Scientific Laboratory. The two programs involved are the general-purpose heat source development and space nuclear safety and fuels. Most of the studies discussed here are of a continuing nature. Results and conclusions described may change as the work continues. Published reference to the results cited in this report should not be made without the explicit permission of the person in charge of the work.

  17. Preliminary reentry safety assessment of the General Purpose Heat Source module for the Cassini mission: Aerospace Nuclear Safety Program

    SciTech Connect

    Conn, D.W.; Brenza, P.T.

    1993-04-01

    As asked by the U. S. Department of Energy/Office of Special Applications, and in support of the Environmental Impact Statement for the Cassini mission, The Johns Hopkins University/Applied Physics Laboratory (JHU/APL) has conducted preliminary one-dimensional ablation and thermal analyses of the General Purpose Heat Source (GPHS). The predicted earth entry conditions provided by the Jet Propulsion Laboratory (JPL) for a Cassini Venus-Venus-Earth-Jupiter Gravity Assist (VVEJGA) trajectory were used as initial conditions. The results of this study which constitute the initial reentry analysis assessment leading to the Cassini Updated Safety, Analysis Report (USAR) are discussed in this document.

  18. A general purpose computer-to-computer interface Xerox Sigma computer-to-DEC PDP 11 computer

    NASA Technical Reports Server (NTRS)

    Fetter, J. L.; Walker, C. M.; Fisher, W.

    1981-01-01

    The Sigma/PDP 11 Interface is a general-purpose system for interconnecting a Xerox Sigma series computer and a DEC PDP 11 series computer. Although the unit is designed to operate in a real-time environment, it can be used in nonreal-time modes as well. Several features, designed to facilitate using the system in varied applications are included in the unit; for example, the features can be used to isolate software or hardware faults. This paper contains descriptions of the hardware and software operations of the interface and examples of real-time applications in the research environment at Ames Research Center.

  19. Experimental determination of the stable-trim attitudes of two proposed, general-purpose, heat-source modules

    NASA Technical Reports Server (NTRS)

    Kruse, Robert L.

    1987-01-01

    Ballistic range tests have been conducted to determine the aerodynamically stable trim attitudes of two proposed general-purpose heat-source module configurations. Tests were conducted at speeds of 4.6 km/sec for the concept module, and at both 4.6 km/sec and 1.4 km/sec for the MOD II. Test results indicated that both configurations were stable when launched in the face-on attitude. When launched in the side-on attitude, the MOD II configuration was found to be stable, while tests of the concept module did not give definitive results.

  20. Classification of LIDAR Data for Generating a High-Precision Roadway Map

    NASA Astrophysics Data System (ADS)

    Jeong, J.; Lee, I.

    2016-06-01

    Generating of a highly precise map grows up with development of autonomous driving vehicles. The highly precise map includes a precision of centimetres level unlike an existing commercial map with the precision of meters level. It is important to understand road environments and make a decision for autonomous driving since a robust localization is one of the critical challenges for the autonomous driving car. The one of source data is from a Lidar because it provides highly dense point cloud data with three dimensional position, intensities and ranges from the sensor to target. In this paper, we focus on how to segment point cloud data from a Lidar on a vehicle and classify objects on the road for the highly precise map. In particular, we propose the combination with a feature descriptor and a classification algorithm in machine learning. Objects can be distinguish by geometrical features based on a surface normal of each point. To achieve correct classification using limited point cloud data sets, a Support Vector Machine algorithm in machine learning are used. Final step is to evaluate accuracies of obtained results by comparing them to reference data The results show sufficient accuracy and it will be utilized to generate a highly precise road map.

  1. High precision locating control system based on VCM for Talbot lithography

    NASA Astrophysics Data System (ADS)

    Yao, Jingwei; Zhao, Lixin; Deng, Qian; Hu, Song

    2016-10-01

    Aiming at the high precision and efficiency requirements of Z-direction locating in Talbot lithography, a control system based on Voice Coil Motor (VCM) was designed. In this paper, we built a math model of VCM and its moving characteristic was analyzed. A double-closed loop control strategy including position loop and current loop were accomplished. The current loop was implemented by driver, in order to achieve the rapid follow of the system current. The position loop was completed by the digital signal processor (DSP) and the position feedback was achieved by high precision linear scales. Feed forward control and position feedback Proportion Integration Differentiation (PID) control were applied in order to compensate for dynamic lag and improve the response speed of the system. And the high precision and efficiency of the system were verified by simulation and experiments. The results demonstrated that the performance of Z-direction gantry was obviously improved, having high precision, quick responses, strong real-time and easily to expend for higher precision.

  2. A high-precision calculation method for interface normal and curvature on an unstructured grid

    NASA Astrophysics Data System (ADS)

    Ito, Kei; Kunugi, Tomoaki; Ohno, Shuji; Kamide, Hideki; Ohshima, Hiroyuki

    2014-09-01

    In the volume-of-fluid algorithm, the calculations of the interface normal and curvature are crucially important for accurately simulating interfacial flows. However, few methods have been proposed for the high-precision interface calculation on an unstructured grid. In this paper, the authors develop a height function method that works appropriately on an unstructured grid. In the process, the definition of the height function is discussed, and the high-precision calculation method of the interface normal is developed to meet the necessary condition for a second-order method. This new method has highly reduced computational cost compared with a conventional high-precision method because the interface normal calculation is completed by solving relatively simple algebraic equations. The curvature calculation method is also discussed and the approximated quadric curve of an interface is employed to calculate the curvature. Following a basic verification, the developed height function method is shown to successfully provide superior calculation accuracy and highly reduced computational cost compared with conventional calculation methods in terms of the interface normal and curvature. In addition, the height function method succeeds in calculating accurately the slotted-disk revolution problem and the oscillating drop on unstructured grids. Therefore, the developed height function method is confirmed to be an efficient technique for the high-precision numerical simulation of interfacial flows on an unstructured grid.

  3. Utilizing a general purpose finite element approach for assessing the rotordynamic response of a flexible disk/shaft system

    NASA Astrophysics Data System (ADS)

    Wroblewski, Adam C.; Gyekenyesi, Andrew L.

    2014-04-01

    With continual improvement in computing power and software codes that simulate multiple physical effects, complex analyses can be performed that allow for more accurate modeling of real world systems. Here, a general purpose finite element (FE) code was utilized to conduct a rotordynamic assessment of a rotor system containing a flexible disk. Typically, specialized rotordynamic software packages make numerous assumptions to simplify the various types of rotor response calculations. Disks, for example, are commonly assumed rigid and are represented by lumped masses or discrete beam elements. Such idealizations may cause inaccuracies when calculating critical speeds for rotor systems that involve a relatively flexible disk. By utilizing a general purpose FE approach, where multiple rotational effects are considered, a more accurate model can be developed that includes the dynamic contributions of a flexible disk. This paper illustrates the rotordynamic analysis of a generic, yet realistic, compressor with a shrouded impeller model, without extensive geometric simplification. Furthermore, through the utilization of the fully featured geometry, several dynamic effects are demonstrated to have a significant influence on the rotor system's Campbell diagram. The dynamic effects investigated include disk flexibility, stress stiffening, and spin softening. It is shown that neglecting any of these may cause significant errors regarding the rotordynamic analysis predictions.

  4. Figures deduction method for mast valuating interpolation errors of encoder with high precision

    NASA Astrophysics Data System (ADS)

    Yi, Jie; An, Li-min; Liu, Chun-xia

    2011-08-01

    With the development of technology, especially the need of fast accurately running after and orientating the aim of horizon and air, the photoelectrical rotary encoder with high precision has become the research hotspot in the fields of international spaceflight and avigation, the errors evaluation of encoder with high precision is the one of the key technology that must to be resolved. For the encoder with high precision, the interpolation errors is the main factor which affects its precision. Existing interpolation errors detection adopts accurate apparatus such as little angle measurement apparatus and optics polyhedron, requesting under the strict laboratory condition to carry on. The detection method is also time-consuming, hard to tackle and easy to introduce detect errors. This paper mainly studies the fast evaluation method of interpolation errors of encoder with high precision which is applied to the working field. Taking the Lissajou's figure produced by moiré fringe as foundation, the paper sets up the radius vector's mathematical model to represent figure's form deviation, analyses the implied parameters information of moiré fringe, the relation of the radius vector deviation and interpolation errors in the figures and puts forward the method of interpolation errors figures evaluation. Adopting figure deduction method, and directly from harmonic component of radius vector deviation toward harmonic component of interpolation errors, the interpolation errors can be gotten in the paper. Through data collecting card, the Moiré fringe signal is transmitted into the computer, then, the computer storages the data, using figures evaluation method to analyses the data, drawing the curve of interpolation errors. Comparing with interpolation errors drawing from traditional detect method, the change trend of the interpolation errors curve is similar, peak-peak value is almost equality. The result of experiment indicates: the method of the paper can be applied to

  5. A compact system for high precision time measurements ( < 14 ps RMS) and integrated data acquisition for a large number of channels

    NASA Astrophysics Data System (ADS)

    Traxler, M.; Bayer, E.; Kajetanowicz, M.; Korcyl, G.; Maier, L.; Michel, J.; Palka, M.; Ugur, C.

    2011-12-01

    A high precision ( < 14 ps RMS time resolution) and high channel density ( ~ 256 channels) Time to Digital Converter (TDC) module (realized in FPGAs) with integrated DAQ is presented. The data is transported over up to 8 Gigabit-Ethernet or optical links with up to 3 Gb/s. Slow-Control information is transported over the same links. It can be attached directly to the detector, which allows the elimination of long cables and crate systems. The full 256 channel TDCs are expected to use approximately 30 W electrical power. The module size is 20 cm by 23 cm. Power is provided by a galvanically isolated 48 V low noise power supply. AddOn-boards adapt to the special needs of the detector to be read out, e.g. containing Charge to Width (Q2W) FEE for PMT readout.

  6. Comparison of nitrous oxide (N2O) analyzers for high-precision measurements of atmospheric mole fractions

    NASA Astrophysics Data System (ADS)

    Lebegue, Benjamin; Schmidt, Martina; Ramonet, Michel; Wastine, Benoit; Yver Kwok, Camille; Laurent, Olivier; Belviso, Sauveur; Guemri, Ali; Philippon, Carole; Smith, Jeremiah; Conil, Sebastien

    2016-03-01

    Over the last few decades, in situ measurements of atmospheric N2O mole fractions have been performed using gas chromatographs (GCs) equipped with electron capture detectors. This technique, however, becomes very challenging when trying to detect the small variations of N2O as the detectors are highly nonlinear and the GCs at remote stations require a considerable amount of maintenance by qualified technicians to maintain good short-term and long-term repeatability. With new robust optical spectrometers now available for N2O measurements, we aim to identify a robust and stable analyzer that can be integrated into atmospheric monitoring networks, such as the Integrated Carbon Observation System (ICOS). In this study, we present the most complete comparison of N2O analyzers, with seven analyzers that were developed and commercialized by five different companies. Each instrument was characterized during a time period of approximately 8 weeks. The test protocols included the characterization of the short-term and long-term repeatability, drift, temperature dependence, linearity and sensitivity to water vapor. During the test period, ambient air measurements were compared under field conditions at the Gif-sur-Yvette station. All of the analyzers showed a standard deviation better than 0.1 ppb for the 10 min averages. Some analyzers would benefit from improvements in temperature stability to reduce the instrument drift, which could then help in reducing the frequency of calibrations. For most instruments, the water vapor correction algorithms applied by companies are not sufficient for high-precision atmospheric measurements, which results in the need to dry the ambient air prior to analysis.

  7. Comparison of nitrous oxide (N2O) analyzers for high-precision measurements of atmospheric mole fractions

    NASA Astrophysics Data System (ADS)

    Lebegue, B.; Schmidt, M.; Ramonet, M.; Wastine, B.; Yver Kwok, C.; Laurent, O.; Belviso, S.; Guemri, A.; Philippon, C.; Smith, J.; Conil, S.; Jost, H. J.; Crosson, E. R.

    2015-10-01

    Over the last few decades, in-situ measurements of atmospheric N2O mole fractions have been performed using gas chromatographs (GCs) equipped with electron capture detectors (ECDs). When trying to meet the World Meteorological Organization's (WMO) quality goal, this technique becomes very challenging as the detectors are highly non-linear and the GCs at remote stations require a considerable amount of maintenance by qualified technicians to maintain good short-term and long-term repeatability. With more robust optical spectrometers being now available for N2O measurements, we aim to identify a robust and stable analyzer that can be integrated into atmospheric monitoring networks, such as the Integrated Carbon Observation System (ICOS). In this study, we tested seven analyzers that were developed and commercialized from five different companies and compared the results with established techniques. Each instrument was characterized during a time period of approximately eight weeks. The test protocols included the characterization of the short-term and long-term repeatability, drift, temperature dependence, linearity and sensitivity to water vapor. During the test period, ambient air measurements were compared under field conditions at the Gif-sur-Yvette station. All of the analyzers showed a standard deviation better than 0.1 ppb for the 10 min averages. Some analyzers would benefit from improvements in temperature stability to reduce the instrument drift, which could then help in reducing the frequency of calibrations. For most instruments, the water vapor correction algorithms applied by companies are not sufficient for high-precision atmospheric measurements, which results in the need to dry the ambient air prior to analysis.

  8. Development of High Precision Metal Micro-Electro-Mechanical-Systems Column for Portable Surface Acoustic Wave Gas Chromatograph

    NASA Astrophysics Data System (ADS)

    Iwaya, Takamitsu; Akao, Shingo; Sakamoto, Toshihiro; Tsuji, Toshihiro; Nakaso, Noritaka; Yamanaka, Kazushi

    2012-07-01

    In the field of environmental measurement and security, a portable gas chromatograph (GC) is required for the on-site analysis of multiple hazardous gases. Although the gas separation column has been downsized using micro-electro-mechanical-systems (MEMS) technology, an MEMS column made of silicon and glass still does not have sufficient robustness and a sufficiently low fabrication cost for a portable GC. In this study, we fabricated a robust and inexpensive high-precision metal MEMS column by combining diffusion-bonded etched stainless-steel plates with alignment evaluation using acoustic microscopy. The separation performance was evaluated using a desktop GC with a flame ionization detector and we achieved the high separation performance comparable to the best silicon MEMS column fabricated using a dynamic coating method. As an application, we fabricated a palm-size surface acoustic wave (SAW) GC combining this column with a ball SAW sensor and succeeded in separating and detecting a mixture of volatile organic compounds.

  9. High-precision image aided inertial navigation with known features: observability analysis and performance evaluation.

    PubMed

    Jiang, Weiping; Wang, Li; Niu, Xiaoji; Zhang, Quan; Zhang, Hui; Tang, Min; Hu, Xiangyun

    2014-10-17

    A high-precision image-aided inertial navigation system (INS) is proposed as an alternative to the carrier-phase-based differential Global Navigation Satellite Systems (CDGNSSs) when satellite-based navigation systems are unavailable. In this paper, the image/INS integrated algorithm is modeled by a tightly-coupled iterative extended Kalman filter (IEKF). Tightly-coupled integration ensures that the integrated system is reliable, even if few known feature points (i.e., less than three) are observed in the images. A new global observability analysis of this tightly-coupled integration is presented to guarantee that the system is observable under the necessary conditions. The analysis conclusions were verified by simulations and field tests. The field tests also indicate that high-precision position (centimeter-level) and attitude (half-degree-level)-integrated solutions can be achieved in a global reference.

  10. High-Precision Image Aided Inertial Navigation with Known Features: Observability Analysis and Performance Evaluation

    PubMed Central

    Jiang, Weiping; Wang, Li; Niu, Xiaoji; Zhang, Quan; Zhang, Hui; Tang, Min; Hu, Xiangyun

    2014-01-01

    A high-precision image-aided inertial navigation system (INS) is proposed as an alternative to the carrier-phase-based differential Global Navigation Satellite Systems (CDGNSSs) when satellite-based navigation systems are unavailable. In this paper, the image/INS integrated algorithm is modeled by a tightly-coupled iterative extended Kalman filter (IEKF). Tightly-coupled integration ensures that the integrated system is reliable, even if few known feature points (i.e., less than three) are observed in the images. A new global observability analysis of this tightly-coupled integration is presented to guarantee that the system is observable under the necessary conditions. The analysis conclusions were verified by simulations and field tests. The field tests also indicate that high-precision position (centimeter-level) and attitude (half-degree-level)-integrated solutions can be achieved in a global reference. PMID:25330046

  11. A high-precision K-band LFMCW radar for range measurement

    NASA Astrophysics Data System (ADS)

    Jia, Yingzhuo; Chen, Xiuwei; Zou, Yongliao

    2016-11-01

    K-band LFMCW radar may be applied in high-precision range measurement, if its range resolution is made be close to mm magnitude, good performance is not only needed in hardware design, algorithm selection and optimization is but also needed. In K-band LFMCW radar system, CZT algorithm is modified according to practical radar echo signal, its simulation model is built in the System Generator tool software, the corresponding algorithm is implemented in FPGA. K-band LFMCW radar may be applied in range measurement of great volume storage tank, the outfield experiment was done according to application, experiment result shows that range measurement precision may reach mm magnitude, the system can meet the requirement of remote high-precision measurement.

  12. A high-precision method for measurement of paleoatmospheric CO2 in small polar ice samples

    NASA Astrophysics Data System (ADS)

    Ahn, Jinho; Brook, Edward J.; Howell, Kate

    We describe a high-precision method, now in use in our laboratory, for measuring the CO2 mixing ratio of ancient air trapped in polar ice cores. Occluded air in ice samples weighing ˜8-15 g is liberated by crushing with steel pins at -35°C and trapped at -263°C in a cryogenic cold trap. CO2 in the extracted air is analyzed using gas chromatography. Replicate measurements for several samples of high-quality ice from the Siple Dome and Taylor Dome Antarctic ice cores have pooled standard deviations of <0.9 ppm. This high-precision technique is directly applicable to high-temporal-resolution studies for detection of small CO2 variations, for example CO2 variations of a few parts per million on millennial to decadal scales.

  13. High-speed high-precision and ultralong-range complex spectral domain dimensional metrology.

    PubMed

    Bao, Wen; Shen, Yi; Chen, Tao; Li, Peng; Ding, Zhihua

    2015-05-04

    A precise, nondestructive dimensional metrological system is crucial to manufacturing and packaging of multi-component optical system. To this end, an orthogonal dispersive spectrometer based complex spectral domain interferometric system for high-speed high-precision and ultralong-range dimensional metrology is developed. An improved complex method based on actual spectral phase shift is proposed to achieve ultrahigh suppression of artifacts. Suppression ratios of 80 dB for DC and 60 dB for mirror images are realized, the highest ratios among existing complex methods. To ensure high-precision in distance determination, an averaged spectral phase measurement algorithm is adopted. A precision of 60 nm within a measurement range of 200 mm without axial movement of the sample is demonstrated. The measurement range is readily extendable if axial movement of the sample and range cascading are involved. The system holds potential applications in various areas for real-time nondestructive testing and evaluation.

  14. Development of a practical method of estimating electric power from various photovoltaic technologies with high precision

    NASA Astrophysics Data System (ADS)

    Ishii, Tetsuyuki; Sato, Ritsuko; Choi, Sungwoo; Chiba, Yasuo; Masuda, Atsushi

    2017-08-01

    The purpose of this study is to develop a method of estimating the electric power from various photovoltaic technologies with high precision. The actual outdoor performance of eight kinds (12 types) of photovoltaic (PV) modules has been measured since January 2012 in order to verify the precision of the method. Using ambient climatic datasets including solar irradiance, module temperature, and solar spectrum, the performance of these PV modules is corrected to the performance under standard test conditions (STC), which should be constant ideally. The results indicate that the performance of bulk crystalline silicon (c-Si) and copper indium gallium diselenide (CIGS) PV modules can be estimated with high precision (approximately less than ±2%). However, the estimation precision of thin-film Si and cadmium telluride (CdTe) PV modules is low because of the initial light-induced degradation and seasonal variation due to metastability.

  15. Optical timing receiver for the NASA laser ranging system. Part 2: High precision time interval digitizer

    NASA Technical Reports Server (NTRS)

    Leskovar, B.; Turko, B.

    1977-01-01

    The development of a high precision time interval digitizer is described. The time digitizer is a 10 psec resolution stop watch covering a range of up to 340 msec. The measured time interval is determined as a separation between leading edges of a pair of pulses applied externally to the start input and the stop input of the digitizer. Employing an interpolation techniques and a 50 MHz high precision master oscillator, the equivalent of a 100 GHz clock frequency standard is achieved. Absolute accuracy and stability of the digitizer are determined by the external 50 MHz master oscillator, which serves as a standard time marker. The start and stop pulses are fast 1 nsec rise time signals, according to the Nuclear Instrument means of tunnel diode discriminators. Firing level of the discriminator define start and stop points between which the time interval is digitized.

  16. Process influences and correction possibilities for high precision injection molded freeform optics

    NASA Astrophysics Data System (ADS)

    Dick, Lars; Risse, Stefan; Tünnermann, Andreas

    2016-08-01

    Modern injection molding processes offer a cost-efficient method for manufacturing high precision plastic optics for high volume applications. Besides form deviation of molded freeform optics, internal material stress is a relevant influencing factor for the functionality of a freeform optics in an optical system. This paper illustrates dominant influence parameters of an injection molding process relating to form deviation and internal material stress based on a freeform demonstrator geometry. Furthermore, a deterministic and efficient way for 3D mold correcting of systematic, asymmetrical shrinkage errors is shown to reach micrometer range shape accuracy at diameters up to 40 mm. In a second case, a stress-optimized parameter combination using unusual molding conditions was 3D corrected to reach high precision and low stress freeform polymer optics.

  17. High-precision tracking with non-blinking quantum dots resolves nanoscale vertical displacement.

    PubMed

    Marchuk, Kyle; Guo, Yijun; Sun, Wei; Vela, Javier; Fang, Ning

    2012-04-11

    Novel non-blinking quantum dots (NBQDs) were utilized in three-dimensional super-localization, high-precision tracking applications under an automated scanning-angle total internal reflection fluorescence microscope (SA-TIRFM). NBQDs were randomly attached to stationary microtubules along the radial axis under gliding assay conditions. By automatically scanning through a wide range of incident angles with different evanescent-field layer thicknesses, the fluorescence intensity decay curves were obtained. Fit with theoretical decay functions, the absolute vertical positions were determined with sub-10-nm localization precision. The emission intensity profile of the NBQDs attached to kinesin-propelled microtubules was used to resolve the self-rotation of gliding microtubules within a small vertical distance of ~50 nm. We demonstrate the applicability of NBQDs in high-precision fluorescence imaging experiments. © 2012 American Chemical Society

  18. Dynamic evaluation system for interpolation errors in the encoder of high precision

    NASA Astrophysics Data System (ADS)

    Wan, Qiu-hua; Wu, Yong-zhi; Zhao, Chang-hai; Liang, Li-hui; Sun, Ying; Jiang, Yong

    2009-05-01

    In order to measure dynamic interpolation errors of photoelectric encoder of high precision, the dynamic evaluation system of interpolation errors is introduced. Firstly, the fine Moiré signal of encoder which is collected with the high-speed data gathering card into the computer is treated to equiangular data with the method of linear interpolation. Then, the analysis of harmonic wave with the FFT is processed. Compared with the standard signal, the dynamic interpolation errors of the encoder are calculated. Experimental results show that the precision of the dynamic evaluation system of interpolation errors is +/-0.1 %( pitch). The evaluation system is simple, fast, high precision, and can be used in the working field of the encoder.

  19. Evaluation of Aqueous and Powder Processing Techniques for Production of Pu-238-Fueled General Purpose Heat Sources

    SciTech Connect

    Not Available

    2008-06-01

    This report evaluates alternative processes that could be used to produce Pu-238 fueled General Purpose Heat Sources (GPHS) for radioisotope thermoelectric generators (RTG). Fabricating GPHSs with the current process has remained essentially unchanged since its development in the 1970s. Meanwhile, 30 years of technological advancements have been made in the fields of chemistry, manufacturing, ceramics, and control systems. At the Department of Energy’s request, alternate manufacturing methods were compared to current methods to determine if alternative fabrication processes could reduce the hazards, especially the production of respirable fines, while producing an equivalent GPHS product. An expert committee performed the evaluation with input from four national laboratories experienced in Pu-238 handling.

  20. VoxelMages: a general-purpose graphical interface for designing geometries and processing DICOM images for PENELOPE.

    PubMed

    Giménez-Alventosa, V; Ballester, F; Vijande, J

    2016-12-01

    The design and construction of geometries for Monte Carlo calculations is an error-prone, time-consuming, and complex step in simulations describing particle interactions and transport in the field of medical physics. The software VoxelMages has been developed to help the user in this task. It allows to design complex geometries and to process DICOM image files for simulations with the general-purpose Monte Carlo code PENELOPE in an easy and straightforward way. VoxelMages also allows to import DICOM-RT structure contour information as delivered by a treatment planning system. Its main characteristics, usage and performance benchmarking are described in detail. Copyright © 2016 Elsevier Ltd. All rights reserved.