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Sample records for high precision experimental

  1. MEASUREMENT AND PRECISION, EXPERIMENTAL VERSION.

    ERIC Educational Resources Information Center

    Harvard Univ., Cambridge, MA. Harvard Project Physics.

    THIS DOCUMENT IS AN EXPERIMENTAL VERSION OF A PROGRAMED TEXT ON MEASUREMENT AND PRECISION. PART I CONTAINS 24 FRAMES DEALING WITH PRECISION AND SIGNIFICANT FIGURES ENCOUNTERED IN VARIOUS MATHEMATICAL COMPUTATIONS AND MEASUREMENTS. PART II BEGINS WITH A BRIEF SECTION ON EXPERIMENTAL DATA, COVERING SUCH POINTS AS (1) ESTABLISHING THE ZERO POINT, (2)…

  2. Proton-proton bremsstrahlung calculation: Comparison with recent high-precision experimental results

    SciTech Connect

    Li Yi; Liou, M.K.; Schreiber, W.M.

    2005-08-01

    Proton-proton bremsstrahlung cross sections and analyzing powers have been calculated at 190 MeV by using a one-boson-exchange model. The results are compared with the recently published high-precision Kernfysisch-Versneller-Instituut (KVI) data. Satisfactory agreement between theory and experiment has been found.

  3. Parameter space of experimental chaotic circuits with high-precision control parameters.

    PubMed

    de Sousa, Francisco F G; Rubinger, Rero M; Sartorelli, José C; Albuquerque, Holokx A; Baptista, Murilo S

    2016-08-01

    We report high-resolution measurements that experimentally confirm a spiral cascade structure and a scaling relationship of shrimps in the Chua's circuit. Circuits constructed using this component allow for a comprehensive characterization of the circuit behaviors through high resolution parameter spaces. To illustrate the power of our technological development for the creation and the study of chaotic circuits, we constructed a Chua circuit and study its high resolution parameter space. The reliability and stability of the designed component allowed us to obtain data for long periods of time (∼21 weeks), a data set from which an accurate estimation of Lyapunov exponents for the circuit characterization was possible. Moreover, this data, rigorously characterized by the Lyapunov exponents, allows us to reassure experimentally that the shrimps, stable islands embedded in a domain of chaos in the parameter spaces, can be observed in the laboratory. Finally, we confirm that their sizes decay exponentially with the period of the attractor, a result expected to be found in maps of the quadratic family. PMID:27586603

  4. Parameter space of experimental chaotic circuits with high-precision control parameters

    NASA Astrophysics Data System (ADS)

    de Sousa, Francisco F. G.; Rubinger, Rero M.; Sartorelli, José C.; Albuquerque, Holokx A.; Baptista, Murilo S.

    2016-08-01

    We report high-resolution measurements that experimentally confirm a spiral cascade structure and a scaling relationship of shrimps in the Chua's circuit. Circuits constructed using this component allow for a comprehensive characterization of the circuit behaviors through high resolution parameter spaces. To illustrate the power of our technological development for the creation and the study of chaotic circuits, we constructed a Chua circuit and study its high resolution parameter space. The reliability and stability of the designed component allowed us to obtain data for long periods of time (˜21 weeks), a data set from which an accurate estimation of Lyapunov exponents for the circuit characterization was possible. Moreover, this data, rigorously characterized by the Lyapunov exponents, allows us to reassure experimentally that the shrimps, stable islands embedded in a domain of chaos in the parameter spaces, can be observed in the laboratory. Finally, we confirm that their sizes decay exponentially with the period of the attractor, a result expected to be found in maps of the quadratic family.

  5. Parameter space of experimental chaotic circuits with high-precision control parameters.

    PubMed

    de Sousa, Francisco F G; Rubinger, Rero M; Sartorelli, José C; Albuquerque, Holokx A; Baptista, Murilo S

    2016-08-01

    We report high-resolution measurements that experimentally confirm a spiral cascade structure and a scaling relationship of shrimps in the Chua's circuit. Circuits constructed using this component allow for a comprehensive characterization of the circuit behaviors through high resolution parameter spaces. To illustrate the power of our technological development for the creation and the study of chaotic circuits, we constructed a Chua circuit and study its high resolution parameter space. The reliability and stability of the designed component allowed us to obtain data for long periods of time (∼21 weeks), a data set from which an accurate estimation of Lyapunov exponents for the circuit characterization was possible. Moreover, this data, rigorously characterized by the Lyapunov exponents, allows us to reassure experimentally that the shrimps, stable islands embedded in a domain of chaos in the parameter spaces, can be observed in the laboratory. Finally, we confirm that their sizes decay exponentially with the period of the attractor, a result expected to be found in maps of the quadratic family.

  6. Experimental setup for precise measurement of losses in high-temperature superconducting transformer

    NASA Astrophysics Data System (ADS)

    Janu, Z.; Wild, J.; Repa, P.; Jelinek, Z.; Zizek, F.; Peksa, L.; Soukup, F.; Tichy, R.

    2006-10-01

    A simple cryogenic system for testing of the superconducting power transformer was constructed. Thermal shielding is provided by additional liquid nitrogen bath instead of super-insulation. The system, together with use of a precise nitrogen liquid level meter, permitted calorimetric measurements of losses of the 8 kVA HTS transformer with a resolution of the order of 0.1 W.

  7. Design and experimental research of a high-precision wavelength controller for tunable fiber Fabry-Perot filters

    NASA Astrophysics Data System (ADS)

    Qi, Hai-bing; Wei, Shu-hua; Wei, Chen

    2013-03-01

    A high-precision wavelength controller is presented in this paper. It is necessary to find out the difference between the central wavelength of a tunable fiber Fabry-Perot (FFP) filter and that of the input laser, while the wavelength controller operates at the states of wavelength-scanning and wavelength-locking modes. Firstly, a dynamic simulation model of tunable FFP filter is established, and the dynamic characteristic of tunable FFP filter modulated by an alternating current (AC) signal is simulated. Then the measuring time at wavelength-scanning mode compared with the theory time is discussed, and this time difference shows the difference between the central wavelength of a tunable FFP filter and that of the input laser. At last, the effects on wavelength-locking precision of time delays, including the time delay of opened-loop circuit, the time constant of the closed-loop circuit and the intrinsic hysteresis of piezoelectric (PZT) element, are analyzed. A wavelength controller of tunable FFP filter is designed and prepared. The experimental results at wavelength-locking mode show that a high locking precision is obtained.

  8. High Precision Astrometry

    NASA Astrophysics Data System (ADS)

    Riess, Adam

    2012-10-01

    This |*|program |*|uses |*|the |*|enhanced |*|astrometric |*|precision |*|enabled |*|by |*|spatial |*|scanning |*|to |*|calibrate |*|remaining |*|obstacles |*|toreaching |*|<<40 |*|microarc|*|second |*|astrometry |*|{<1 |*|millipixel} |*|with |*|WFC3/UVIS |*|by |*|1} |*|improving |*|geometric |*|distor-on |*|2} |*|calibratingthe |*|e|*|ect |*|of |*|breathing |*|on |*|astrometry|*|3} |*|calibrating |*|the |*|e|*|ect |*|of |*|CTE |*|on |*|astrometry, |*|4} |*|characterizing |*|the |*|boundaries |*|andorientations |*|of |*|the |*|WFC3 |*|lithograph |*|cells.

  9. High precision laser sclerostomy

    NASA Astrophysics Data System (ADS)

    Góra, W. S.; Urich, A.; McIntosh, L.; Carter, R. M.; Wilson, C. G.; Dhillon, B.; Hand, D. P.; Shephard, J. D.

    2015-03-01

    Ultrafast lasers offer a possibility of removing soft ophthalmic tissue without introducing collateral damage at the ablation site or in the surrounding tissue. The potential for using ultrashort pico- and femtosecond pulse lasers for modification of ophthalmic tissue has been reported elsewhere and has resulted in the introduction of new, minimally invasive procedures into clinical practice. Our research aims to define the most efficient parameters to allow for the modification of scleral tissue without introducing collateral damage. Our experiments were carried out on hydrated porcine sclera in vitro. Porcine sclera, which has similar collagen organization, histology and water content (~70%) to human tissue was used. Supporting this work we present a 2D finite element blow-off model which employs a one-step heating process. It is assumed that the incident laser radiation that is not reflected is absorbed in the tissue according to the Beer-Lambert law and transformed into heat energy. The experimental setup uses an industrial picosecond laser (TRUMPF TruMicro 5x50) with 5.9 ps pulses at 1030 nm, with pulse energies up to 125 μJ and a focused spot diameter of 35 μm. Use of a beam steering scan head allows flexibility in designing complicated scanning patterns. In this study we have demonstrated that picosecond pulses are capable of removing scleral tissue without introducing any major thermal damage which offers a possible route for minimally invasive sclerostomy. In assessing this we have tested several different scanning patterns including single line ablation, square and circular cavity removal.

  10. 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.

  11. Experimental investigation on focusing characteristics of a He-Ne laser using circular Fresnel zone plate for high-precision alignment of linear accelerators

    SciTech Connect

    Suwada, Tsuyoshi; Satoh, Masanori; Telada, Souichi; Minoshima, Kaoru

    2012-05-15

    We experimentally investigate the focusing characteristics of a He-Ne laser at the focal region for the high-precision alignment of long-distance linear accelerators using a circular Fresnel zone plate. The laser wave passing through the Fresnel zone plate having a focal length of 66.7 m propagates for a 268-m-long distance at atmospheric pressure. A new laser-based alignment system using Fresnel zone plates as the alignment targets is discussed. The transverse displacement of the focused spot of the laser is measured as a function of the displacement of the target by a detector installed at the focal point. Systematic studies on the focusing characteristics and alignment precision have been successfully conducted in this experiment. The experimental results are in good agreement with theoretical calculations, and the alignment precision of the target is determined to be less than {+-}30 {mu}m. In this study, we perform a detailed experimental investigation on the laser propagation and focusing characteristics using the circular Fresnel zone plate at the focal region along with theoretical calculations.

  12. 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…

  13. An experimental analysis of accuracy and precision of a high-speed strain-gage system based on the direct-resistance method

    NASA Astrophysics Data System (ADS)

    Cappa, P.; del Prete, Z.

    1992-03-01

    An experimental study on the relative merits of using a high-speed digital-acquisition system to measure directly the strain-gage resistance, rather than using a conventional Wheatstone bridge, is carried out. Both strain gages, with a nominal resistance of 120 ohm and 1 kohm, were simulated with precision resistors, and the output signals were acquired over a time of 48 and 144 hours; furthermore, the effects in metrological performances caused by a statistical filtering were evaluated. The results show that the implementation of the statistical filtering gains a considerable improvement in gathering strain-gage-resistance readings. On the other hand, such a procedure causes, obviously, a loss of performance with regard to the acquisition rate, and therefore to the dynamic data-collecting capabilities. In any case, the intrinsic resolution of the 12-bit a/d converter, utilized in the present experimental analysis, causes a limitation for measurement accuracy in the range of hundreds microns/m.

  14. High precision laser forming for microactuation

    NASA Astrophysics Data System (ADS)

    Folkersma, Ger K. G. P.; Römer, G. R. B. E.; Brouwer, D. M.; Huis in't Veld, A. J.

    2014-03-01

    For assembly of micro-devices, such as photonic devices, the precision alignment of components is often critical for their performance. Laser forming, also known as laser-adjusting, can be used to create an integrated microactuator to align the components with sub-micron precision after bonding. In this paper a so-called three-bridge planar manipulator was used to study the laser-material interaction and thermal and mechanical behavior of the laser forming mechanism. A 3-D Finite Element Method (FEM) model and experiments are used to identify the optimal parameter settings for a high precision actuator. The goal in this paper is to investigate how precise the maximum occurring temperature and the resulting displacement are predicted by a 3-D FEM model by comparing with experimental results. A secondary goal is to investigate the resolution of the mechanism and the range of motion. With the experimental setup we measure the displacement and surface temperature in real-time. The time-dependent heat transfer FEM models match closely with experimental results, however the structural model can deviate more than 100% in absolute displacement. Experimentally, a positioning resolution of 0.1μm was achieved, with a total stroke exceeding 20μm. A spread of 10% in the temperature cycles between several experiments was found, which was attributed to a spread in the surface absorptivity. Combined with geometric tolerances, the spread in displacement can be as large as 20%. This implies that feedback control of the laser power, in combination with iterative learning during positioning, is required for high precision alignment. Even though the FEM models deviate substantially from the experiments, the 3-D FEM model predicts the trend in deformation sufficiently accurate to use it for design optimization of high precision 3-D actuators using laser adjusting.

  15. 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.

  16. 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.

  17. 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.

  18. Towards High Precision Deuteron Polarimetry

    SciTech Connect

    Silva e Silva, M. da

    2009-08-04

    A finite electric dipole moment (EDM) in any fundamental system would constitute a signal for new physics. The deuteron presents itself as an optimal candidate both experimentally and theoretically. A new storage ring technique is being developed for which a small change in the vertical polarization would be a signal of a non-zero EDM. A novel polarimeter concept is under investigation. Besides being highly efficient, this polarimeter should continuously monitor the beam polarization, guaranteeing optimal sensitivity. Detailed studies on systematic error control, in addition to the measurement of cross sections and analyzing powers, were carried out at KVI-Groningen in The Netherlands. Measurements were conducted at COSY-Juelich in Germany yielding high efficiencies. The (statistics limited) ability to track changes in polarization at the level of a few hundred parts-per-million has been demonstrated. Further studies and developments to meet the final goal of sub-part-per-million sensitivity are in progress.

  19. High precision anatomy for MEG.

    PubMed

    Troebinger, Luzia; López, José David; Lutti, Antoine; Bradbury, David; Bestmann, Sven; Barnes, Gareth

    2014-02-01

    Precise MEG estimates of neuronal current flow are undermined by uncertain knowledge of the head location with respect to the MEG sensors. This is either due to head movements within the scanning session or systematic errors in co-registration to anatomy. Here we show how such errors can be minimized using subject-specific head-casts produced using 3D printing technology. The casts fit the scalp of the subject internally and the inside of the MEG dewar externally, reducing within session and between session head movements. Systematic errors in matching to MRI coordinate system are also reduced through the use of MRI-visible fiducial markers placed on the same cast. Bootstrap estimates of absolute co-registration error were of the order of 1mm. Estimates of relative co-registration error were <1.5mm between sessions. We corroborated these scalp based estimates by looking at the MEG data recorded over a 6month period. We found that the between session sensor variability of the subject's evoked response was of the order of the within session noise, showing no appreciable noise due to between-session movement. Simulations suggest that the between-session sensor level amplitude SNR improved by a factor of 5 over conventional strategies. We show that at this level of coregistration accuracy there is strong evidence for anatomical models based on the individual rather than canonical anatomy; but that this advantage disappears for errors of greater than 5mm. This work paves the way for source reconstruction methods which can exploit very high SNR signals and accurate anatomical models; and also significantly increases the sensitivity of longitudinal studies with MEG. PMID:23911673

  20. High precision anatomy for MEG☆

    PubMed Central

    Troebinger, Luzia; López, José David; Lutti, Antoine; Bradbury, David; Bestmann, Sven; Barnes, Gareth

    2014-01-01

    Precise MEG estimates of neuronal current flow are undermined by uncertain knowledge of the head location with respect to the MEG sensors. This is either due to head movements within the scanning session or systematic errors in co-registration to anatomy. Here we show how such errors can be minimized using subject-specific head-casts produced using 3D printing technology. The casts fit the scalp of the subject internally and the inside of the MEG dewar externally, reducing within session and between session head movements. Systematic errors in matching to MRI coordinate system are also reduced through the use of MRI-visible fiducial markers placed on the same cast. Bootstrap estimates of absolute co-registration error were of the order of 1 mm. Estimates of relative co-registration error were < 1.5 mm between sessions. We corroborated these scalp based estimates by looking at the MEG data recorded over a 6 month period. We found that the between session sensor variability of the subject's evoked response was of the order of the within session noise, showing no appreciable noise due to between-session movement. Simulations suggest that the between-session sensor level amplitude SNR improved by a factor of 5 over conventional strategies. We show that at this level of coregistration accuracy there is strong evidence for anatomical models based on the individual rather than canonical anatomy; but that this advantage disappears for errors of greater than 5 mm. This work paves the way for source reconstruction methods which can exploit very high SNR signals and accurate anatomical models; and also significantly increases the sensitivity of longitudinal studies with MEG. PMID:23911673

  1. High precision triangular waveform generator

    DOEpatents

    Mueller, Theodore R.

    1983-01-01

    An ultra-linear ramp generator having separately programmable ascending and descending ramp rates and voltages is provided. Two constant current sources provide the ramp through an integrator. Switching of the current at current source inputs rather than at the integrator input eliminates switching transients and contributes to the waveform precision. The triangular waveforms produced by the waveform generator are characterized by accurate reproduction and low drift over periods of several hours. The ascending and descending slopes are independently selectable.

  2. Pitch evaluation of high-precision gratings

    NASA Astrophysics Data System (ADS)

    Lu, Yancong; Zhou, Changhe; Wei, Chunlong; Jia, Wei; Xiang, Xiansong; Li, Yanyang; Yu, Junjie; Li, Shubin; Wang, Jin; Liu, Kun; Wei, Shengbin

    2014-11-01

    Optical encoders and laser interferometers are two primary solutions in nanometer metrology. As the precision of encoders depends on the uniformity of grating pitches, it is essential to evaluate pitches accurately. We use a CCD image sensor to acquire grating image for evaluating the pitches with high precision. Digital image correlation technique is applied to filter out the noises. We propose three methods for determining the pitches of grating with peak positions of correlation coefficients. Numerical simulation indicated the average of pitch deviations from the true pitch and the pitch variations are less than 0.02 pixel and 0.1 pixel for these three methods when the ideal grating image is added with salt and pepper noise, speckle noise, and Gaussian noise. Experimental results demonstrated that our method can measure the pitch of the grating accurately, for example, our home-made grating with 20μm period has 475nm peak-to-valley uniformity with 40nm standard deviation during 35mm range. Another measurement illustrated that our home-made grating has 40nm peak-to-valley uniformity with 10nm standard deviation. This work verified that our lab can fabricate high-accuracy gratings which should be interesting for practical application in optical encoders.

  3. High Precision Laser Range Sensor

    NASA Technical Reports Server (NTRS)

    Dubovitsky, Serge (Inventor); Lay, Oliver P. (Inventor)

    2003-01-01

    The present invention is an improved distance measuring interferometer that includes high speed phase modulators and additional phase meters to generate and analyze multiple heterodyne signal pairs with distinct frequencies. Modulation sidebands with large frequency separation are generated by the high speed electro-optic phase modulators, requiring only a single frequency stable laser source and eliminating the need for a fist laser to be tuned or stabilized relative to a second laser. The combination of signals produced by the modulated sidebands is separated and processed to give the target distance. The resulting metrology apparatus enables a sensor with submicron accuracy or better over a multi- kilometer ambiguity range.

  4. New High Precision Linelist of H_3^+

    NASA Astrophysics Data System (ADS)

    Hodges, James N.; Perry, Adam J.; Markus, Charles; Jenkins, Paul A., II; Kocheril, G. Stephen; McCall, Benjamin J.

    2014-06-01

    As the simplest polyatomic molecule, H_3^+ serves as an ideal benchmark for theoretical predictions of rovibrational energy levels. By strictly ab initio methods, the current accuracy of theoretical predictions is limited to an impressive one hundredth of a wavenumber, which has been accomplished by consideration of relativistic, adiabatic, and non-adiabatic corrections to the Born-Oppenheimer PES. More accurate predictions rely on a treatment of quantum electrodynamic effects, which have improved the accuracies of vibrational transitions in molecular hydrogen to a few MHz. High precision spectroscopy is of the utmost importance for extending the frontiers of ab initio calculations, as improved precision and accuracy enable more rigorous testing of calculations. Additionally, measuring rovibrational transitions of H_3^+ can be used to predict its forbidden rotational spectrum. Though the existing data can be used to determine rotational transition frequencies, the uncertainties are prohibitively large. Acquisition of rovibrational spectra with smaller experimental uncertainty would enable a spectroscopic search for the rotational transitions. The technique Noise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy, or NICE-OHVMS has been previously used to precisely and accurately measure transitions of H_3^+, CH_5^+, and HCO^+ to sub-MHz uncertainty. A second module for our optical parametric oscillator has extended our instrument's frequency coverage from 3.2-3.9 μm to 2.5-3.9 μm. With extended coverage, we have improved our previous linelist by measuring additional transitions. O. L. Polyansky, et al. Phil. Trans. R. Soc. A (2012), 370, 5014--5027. J. Komasa, et al. J. Chem. Theor. Comp. (2011), 7, 3105--3115. C. M. Lindsay, B. J. McCall, J. Mol. Spectrosc. (2001), 210, 66--83. J. N. Hodges, et al. J. Chem. Phys. (2013), 139, 164201.

  5. 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.

  6. Precision Crystal Calorimeters in High Energy Physics

    ScienceCinema

    Ren-Yuan Zhu

    2016-07-12

    Precision crystal calorimeters traditionally play an important role in high energy physics experiments. In the last two decades, it faces a challenge to maintain its precision in a hostile radiation environment. This paper reviews the performance of crystal calorimeters constructed for high energy physics experiments and the progress achieved in understanding crystal’s radiation damage as well as in developing high quality scintillating crystals for particle physics. Potential applications of new generation scintillating crystals of high density and high light yield, such as LSO and LYSO, in particle physics experiments is also discussed.

  7. High-precision arithmetic in mathematical physics

    DOE PAGESBeta

    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.

  8. Cellular signalling effects in high precision radiotherapy

    NASA Astrophysics Data System (ADS)

    McMahon, Stephen J.; McGarry, Conor K.; Butterworth, Karl T.; Jain, Suneil; O'Sullivan, Joe M.; Hounsell, Alan R.; Prise, Kevin M.

    2015-06-01

    Radiotherapy is commonly planned on the basis of physical dose received by the tumour and surrounding normal tissue, with margins added to address the possibility of geometric miss. However, recent experimental evidence suggests that intercellular signalling results in a given cell’s survival also depending on the dose received by neighbouring cells. A model of radiation-induced cell killing and signalling was used to analyse how this effect depends on dose and margin choices. Effective Uniform Doses were calculated for model tumours in both idealised cases with no delivery uncertainty and more realistic cases incorporating geometric uncertainty. In highly conformal irradiation, a lack of signalling from outside the target leads to reduced target cell killing, equivalent to under-dosing by up to 10% compared to large uniform fields. This effect is significantly reduced when higher doses per fraction are considered, both increasing the level of cell killing and reducing margin sensitivity. These effects may limit the achievable biological precision of techniques such as stereotactic radiotherapy even in the absence of geometric uncertainties, although it is predicted that larger fraction sizes reduce the relative contribution of cell signalling driven effects. These observations may contribute to understanding the efficacy of hypo-fractionated radiotherapy.

  9. Precision control of high temperature furnaces

    SciTech Connect

    Pollock, G.G.

    1994-12-31

    It is an object of the present invention to provide precision control of high temperature furnaces. It is another object of the present invention to combine the power of two power supplies of greatly differing output capacities in a single furnace. This invention combines two power supplies to control a furnace. A main power supply heats the furnace in the traditional manner, while the power from the auxiliary supply is introduced as a current flow through charged particles existing due to ionized gas or thermionic emission. The main power supply provides the bulk heating power and the auxiliary supply provides a precise and fast power source such that the precision of the total power delivered to the furnace is improved. Further, this invention comprises a means for high speed measurement of temperature of the process by the method of measuring the amount of current flow in a deliberately induced charged particle current.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. High bandwidth control of precision motion instrumentation

    NASA Astrophysics Data System (ADS)

    Bristow, Douglas A.; Dong, Jingyan; Alleyne, Andrew G.; Ferreira, Placid; Salapaka, Srinivas

    2008-10-01

    This article presents a high-bandwidth control design suitable for precision motion instrumentation. Iterative learning control (ILC), a feedforward technique that uses previous iterations of the desired trajectory, is used to leverage the repetition that occurs in many tasks, such as raster scanning in microscopy. Two ILC designs are presented. The first design uses the motion system dynamic model to maximize bandwidth. The second design uses a time-varying bandwidth that is particularly useful for nonsmooth trajectories such as raster scanning. Both designs are applied to a multiaxis piezoelectric-actuated flexure system and evaluated on a nonsmooth trajectory. The ILC designs demonstrate significant bandwidth and precision improvements over the feedback controller, and the ability to achieve precision motion control at frequencies higher than multiple system resonances.

  15. 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.

  16. 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.

  17. 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.

  18. Calibration of a high precision rotary table

    NASA Astrophysics Data System (ADS)

    Wang, Heyan; Xue, Zi; Shen, Ni; Huang, Yao

    2015-02-01

    In order to calibrate a high precision rotary table, a calibration system was established to measure the position error and repeatability of rotary table. The position error was measured with a polygon, an index table and an autocollimator to separate the angular error of the polygon from the position error of the rotary table, and the position error of rotary table was calculated using least square method. The rotary table was compensated and calibrated with the position error measured. The repeatability of the rotary table established through 10 times full circle rotations was 0.02 arc second. The measurement results indicated that the combination calibration method was suitable for the calibration of a high precision rotary table. It was found through the analysis that the angular measurement uncertainty was 0.08 arc second.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Precision mass measurements of highly charged ions

    NASA Astrophysics Data System (ADS)

    Kwiatkowski, A. A.; Bale, J. C.; Brunner, T.; Chaudhuri, A.; Chowdhury, U.; Ettenauer, S.; Frekers, D.; Gallant, A. T.; Grossheim, A.; Lennarz, A.; Mane, E.; MacDonald, T. D.; Schultz, B. E.; Simon, M. C.; Simon, V. V.; Dilling, J.

    2012-10-01

    The reputation of Penning trap mass spectrometry for accuracy and precision was established with singly charged ions (SCI); however, the achievable precision and resolving power can be extended by using highly charged ions (HCI). The TITAN facility has demonstrated these enhancements for long-lived (T1/2>=50 ms) isobars and low-lying isomers, including ^71Ge^21+, ^74Rb^8+, ^78Rb^8+, and ^98Rb^15+. The Q-value of ^71Ge enters into the neutrino cross section, and the use of HCI reduced the resolving power required to distinguish the isobars from 3 x 10^5 to 20. The precision achieved in the measurement of ^74Rb^8+, a superallowed β-emitter and candidate to test the CVC hypothesis, rivaled earlier measurements with SCI in a fraction of the time. The 111.19(22) keV isomeric state in ^78Rb was resolved from the ground state. Mass measurements of neutron-rich Rb and Sr isotopes near A = 100 aid in determining the r-process pathway. Advanced ion manipulation techniques and recent results will be presented.

  5. 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.

  6. Precision timing measurements for high energy photons

    SciTech Connect

    Anderson, Dustin; Apreysan, Artur; Bornheim, Adi; Duarte, Javier; Newman, Harvey; Pena, Cristian; Ronzhin, Anatoly; Spiropulu, Maria; Trevor, Jason; Xie, Si; Zhu, Ren-Yuan

    2014-11-21

    Particle colliders operating at high luminosities present challenging environments for high energy physics event reconstruction and analysis. We discuss how timing information, with a precision on the order of 10 ps, can aid in the reconstruction of physics events under such conditions. We present calorimeter based timing measurements from test beam experiments in which we explore the ultimate timing precision achievable for high energy photons or electrons of 10 GeV and above. Using a prototype calorimeter consisting of a 1.7×1.7×1.7 cm3 lutetium–yttrium oxyortho-silicate (LYSO) crystal cube, read out by micro-channel plate photomultipliers, we demonstrate a time resolution of 33.5±2.1 ps for an incoming beam energy of 32 GeV. In a second measurement, using a 2.5×2.5×20 cm3 LYSO crystal placed perpendicularly to the electron beam, we achieve a time resolution of 59±11 ps using a beam energy of 4 GeV. We also present timing measurements made using a shashlik-style calorimeter cell made of LYSO and tungsten plates, and demonstrate that the apparatus achieves a time resolution of 54±5 ps for an incoming beam energy of 32 GeV.

  7. Location of end-points in high-precision coulometry.

    PubMed

    Koch, W F; Poe, D P; Diehl, H

    1975-07-01

    A computer has been used to fit a cubic equation to experimental data obtained in the region of the end-point in high-precision coulometric titrations of 4-aminopyridine and tris(hydroxy-methyl) aminomethane. For these weak bases, the two end-points (points of inflexion calculated by setting the second derivative equal to zero) obtained by choosing first time, and secondly pH, as the independent variable, are in good agreement.

  8. Precisely parameterized experimental and computational models of tissue organization.

    PubMed

    Molitoris, Jared M; Paliwal, Saurabh; Sekar, Rajesh B; Blake, Robert; Park, JinSeok; Trayanova, Natalia A; Tung, Leslie; Levchenko, Andre

    2016-02-01

    Patterns of cellular organization in diverse tissues frequently display a complex geometry and topology tightly related to the tissue function. Progressive disorganization of tissue morphology can lead to pathologic remodeling, necessitating the development of experimental and theoretical methods of analysis of the tolerance of normal tissue function to structural alterations. A systematic way to investigate the relationship of diverse cell organization to tissue function is to engineer two-dimensional cell monolayers replicating key aspects of the in vivo tissue architecture. However, it is still not clear how this can be accomplished on a tissue level scale in a parameterized fashion, allowing for a mathematically precise definition of the model tissue organization and properties down to a cellular scale with a parameter dependent gradual change in model tissue organization. Here, we describe and use a method of designing precisely parameterized, geometrically complex patterns that are then used to control cell alignment and communication of model tissues. We demonstrate direct application of this method to guiding the growth of cardiac cell cultures and developing mathematical models of cell function that correspond to the underlying experimental patterns. Several anisotropic patterned cultures spanning a broad range of multicellular organization, mimicking the cardiac tissue organization of different regions of the heart, were found to be similar to each other and to isotropic cell monolayers in terms of local cell-cell interactions, reflected in similar confluency, morphology and connexin-43 expression. However, in agreement with the model predictions, different anisotropic patterns of cell organization, paralleling in vivo alterations of cardiac tissue morphology, resulted in variable and novel functional responses with important implications for the initiation and maintenance of cardiac arrhythmias. We conclude that variations of tissue geometry and topology

  9. Precisely parameterized experimental and computational models of tissue organization†

    PubMed Central

    Sekar, Rajesh B.; Blake, Robert; Park, JinSeok; Trayanova, Natalia A.; Tung, Leslie; Levchenko, Andre

    2016-01-01

    Patterns of cellular organization in diverse tissues frequently display a complex geometry and topology tightly related to the tissue function. Progressive disorganization of tissue morphology can lead to pathologic remodeling, necessitating the development of experimental and theoretical methods of analysis of the tolerance of normal tissue function to structural alterations. A systematic way to investigate the relationship of diverse cell organization to tissue function is to engineer two-dimensional cell monolayers replicating key aspects of the in vivo tissue architecture. However, it is still not clear how this can be accomplished on a tissue level scale in a parameterized fashion, allowing for a mathematically precise definition of the model tissue organization and properties down to a cellular scale with a parameter dependent gradual change in model tissue organization. Here, we describe and use a method of designing precisely parameterized, geometrically complex patterns that are then used to control cell alignment and communication of model tissues. We demonstrate direct application of this method to guiding the growth of cardiac cell cultures and developing mathematical models of cell function that correspond to the underlying experimental patterns. Several anisotropic patterned cultures spanning a broad range of multicellular organization, mimicking the cardiac tissue organization of different regions of the heart, were found to be similar to each other and to isotropic cell monolayers in terms of local cell–cell interactions, reflected in similar confluency, morphology and connexin-43 expression. However, in agreement with the model predictions, different anisotropic patterns of cell organization, paralleling in vivo alterations of cardiac tissue morphology, resulted in variable and novel functional responses with important implications for the initiation and maintenance of cardiac arrhythmias. We conclude that variations of tissue geometry and

  10. Nab: precise experimental study of unpolarized neutron beta decay

    NASA Astrophysics Data System (ADS)

    Pocanic, Dinko; Nab Collaboration

    2014-09-01

    Nab, a program of experimental study of unpolarized neutron decays at the Spallation Neutron Source, Oak Ridge, TN, aims to determine a, the electron-neutrino correlation with precision of δa / a =10-3 , and b, the Fierz interference term, with uncertainty δb ~= 3 ×10-3 . Neutron beta decay's simple theoretical description in the Standard Model (SM) is overconstrained by the set of available observables, providing opportunities to search for evidence of SM extensions. Planned Nab results will lead to a new precise determination of the ratio λ =GA /GV , and to significant reductions in the allowed limits for both right- and left-handed scalar and tensor currents. Alternatively, the experiment may detect a discrepancy from SM predictions consistent with certain realizations of supersymmetry. An optimized, asymmetric spectrometer has been designed to achieve the narrow proton momentum response function required to meet the physics goals of the experiment. The apparatus is to be used in a follow-up measurement (ABba) of asymmetry observables A and B in polarized neutron decay. Nab is funded, now in the construction stage, with planned beam readiness in 2016. We discuss the experiment's motivation, expected reach, design and method. Nab, a program of experimental study of unpolarized neutron decays at the Spallation Neutron Source, Oak Ridge, TN, aims to determine a, the electron-neutrino correlation with precision of δa / a =10-3 , and b, the Fierz interference term, with uncertainty δb ~= 3 ×10-3 . Neutron beta decay's simple theoretical description in the Standard Model (SM) is overconstrained by the set of available observables, providing opportunities to search for evidence of SM extensions. Planned Nab results will lead to a new precise determination of the ratio λ =GA /GV , and to significant reductions in the allowed limits for both right- and left-handed scalar and tensor currents. Alternatively, the experiment may detect a discrepancy from SM

  11. Experimental evaluation of active-member control of precision structures

    NASA Technical Reports Server (NTRS)

    Fanson, James; Blackwood, Gary; Chu, Cheng-Chih

    1989-01-01

    The results of closed loop experiments that use piezoelectric active-members to control the flexible motion of a precision truss structure are described. These experiments are directed toward the development of high-performance structural systems as part of the Control/Structure Interaction (CSI) program at JPL. The focus of CSI activity at JPL is to develop the technology necessary to accurately control both the shape and vibration levels in the precision structures from which proposed large space-based observatories will be built. Structural error budgets for these types of structures will likely be in the sub-micron regime; optical tolerances will be even tighter. In order to achieve system level stability and local positioning at this level, it is generally expected that some form of active control will be required.

  12. Experimental analysis on the rapid measurement of a high precision Brillouin scattering spectrum in water using a Fabry-Pérot etalon

    NASA Astrophysics Data System (ADS)

    Zhou, Bo; Fan, Qiming; Ma, Yong; Yao, Yuan; Li, Hao; Huang, Jun; Liang, Kun

    2016-05-01

    The Brillouin lidar system with a Fabry-Pérot (F-P) etalon has been widely used in remote sensing to study ocean characteristics such as temperature, sound speed, etc. In this system, the measurement error stemming from the spectral broadening of an F-P etalon was typically neglected in applications where high measurement accuracy was not essential. In this paper, an integration method on radius and a convolution method on frequency are proposed to remove the broadening effect and improve the measurement accuracy, respectively. Experiments of underwater Brillouin scattering show that both fitting methods effectively reduce the measurement error due to the transmission function of an F-P etalon. A temperature accuracy of 0.1 °C and a salinity accuracy of 0.5‰ were achieved. Moreover, with the convolution method, the computational cost was reduced to 3 s, which enables rapid measurement of Brillouin shift and linewidth and makes the on-line remote sensing applications possible.

  13. 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.

  14. A Double Precision High Speed Convolution Processor

    NASA Astrophysics Data System (ADS)

    Larochelle, F.; Coté, J. F.; Malowany, A. S.

    1989-11-01

    There exist several convolution processors on the market that can process images at video rate. However, none of these processors operates in floating point arithmetic. Unfortunately, many image processing algorithms presently under development are inoperable in integer arithmetic, forcing the researchers to use regular computers. To solve this problem, we designed a specialized convolution processor that operates in double precision floating point arithmetic with a throughput several thousand times faster than the one obtained on regular computer. Its high performance is attributed to a VLSI double precision convolution systolic cell designed in our laboratories. A 9X9 systolic array carries out, in a pipeline manner, every arithmetic operation. The processor is designed to interface directly with the VME Bus. A DMA chip is responsible for bringing the original pixel intensities from the memory of the computer to the systolic array and to return the convolved pixels back to memory. A special use of 8K RAMs allows an inexpensive and efficient way of delaying the pixel intensities in order to supply the right sequence to the systolic array. On board circuitry converts pixel values into floating point representation when the image is originally represented with integer values. An additional systolic cell, used as a pipeline adder at the output of the systolic array, offers the possibility of combining images together which allows a variable convolution window size and color image processing.

  15. High efficiency francium trap for precision spectroscopy

    NASA Astrophysics Data System (ADS)

    Aubin, Seth Andre Morgan

    We cooled and trapped francium in a high efficiency magneto-optical trap. The francium is produced artificially in a nuclear fusion reaction using the Stony Brook superconducting LINAC. We observed an average trap population of 50,000 210Fr, corresponding to a trapping efficiency of 1.2%. The trapped atoms are cooled to a temperature of 75 muK. We used the new trapping apparatus for spectroscopic studies of the 9S 1/2 level of 210Fr to test the precision of atomic theory. We measured the hyperfine splitting of the 9S1/2 level, and with time-correlated single photon counting, we measured its radiative lifetime. We found a lifetime of 107.53 +/- 0.80 ns and a hyperfine splitting of 4045.1 +/- 1.1 MHz. We characterized the optical properties of a dipole trap based on an axicon lens to provide a low perturbation environment for precision spectroscopy. The axicon generates a region of darkness surrounded by light. For blue-detuned light, cold atoms are trapped in the dark region and experience almost no perturbing fields. This work continues the spectroscopic studies of francium for tests of atomic theory and opens the way for nuclear anapole moment measurements.

  16. 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.

  17. Layered compression for high-precision depth data.

    PubMed

    Miao, Dan; Fu, Jingjing; Lu, Yan; Li, Shipeng; Chen, Chang Wen

    2015-12-01

    With the development of depth data acquisition technologies, access to high-precision depth with more than 8-b depths has become much easier and determining how to efficiently represent and compress high-precision depth is essential for practical depth storage and transmission systems. In this paper, we propose a layered high-precision depth compression framework based on an 8-b image/video encoder to achieve efficient compression with low complexity. Within this framework, considering the characteristics of the high-precision depth, a depth map is partitioned into two layers: 1) the most significant bits (MSBs) layer and 2) the least significant bits (LSBs) layer. The MSBs layer provides rough depth value distribution, while the LSBs layer records the details of the depth value variation. For the MSBs layer, an error-controllable pixel domain encoding scheme is proposed to exploit the data correlation of the general depth information with sharp edges and to guarantee the data format of LSBs layer is 8 b after taking the quantization error from MSBs layer. For the LSBs layer, standard 8-b image/video codec is leveraged to perform the compression. The experimental results demonstrate that the proposed coding scheme can achieve real-time depth compression with satisfactory reconstruction quality. Moreover, the compressed depth data generated from this scheme can achieve better performance in view synthesis and gesture recognition applications compared with the conventional coding schemes because of the error control algorithm. PMID:26415171

  18. Highly damped kinematic coupling for precision instruments

    DOEpatents

    Hale, Layton C.; Jensen, Steven A.

    2001-01-01

    A highly damped kinematic coupling for precision instruments. The kinematic coupling provides support while causing essentially no influence to its nature shape, with such influences coming, for example, from manufacturing tolerances, temperature changes, or ground motion. The coupling uses three ball-cone constraints, each combined with a released flexural degree of freedom. This arrangement enables a gain of higher load capacity and stiffness, but can also significantly reduce the friction level in proportion to the ball radius divided by the distance between the ball and the hinge axis. The blade flexures reduces somewhat the stiffness of the coupling and provides an ideal location to apply constrained-layer damping which is accomplished by attaching a viscoelastic layer and a constraining layer on opposite sides of each of the blade flexures. The three identical ball-cone flexures provide a damped coupling mechanism to kinematically support the projection optics system of the extreme ultraviolet lithography (EUVL) system, or other load-sensitive apparatus.

  19. High precision droplet based new form manufacturing

    SciTech Connect

    Aceves,S; Hadjiconstantinou, N; Miller, W O; Orme, M; Sahai, V; Shapiro, A B

    1999-09-16

    In collaboration with the University of California at Irvine (UCI), we are working on a new technology that relies on the precise deposition of nanoliter molten-metal droplets that are targeted onto a substrate by electrostatic charging and deflection. By this way, three-dimensional (3D) structural materials can be manufactured microlayer by microlayer. Because the volume of the droplets are small, they rapidly solidify on impact, bringing forth a material component with fine grain structures which lead to enhanced material properties (e.g., strength). UCI is responsible for an experimental investigation of the manufacturing feasibility of this process. LLNL has unique expertise in the computational modeling of 3D heat transfer and solid mechanics and has the large-scale computer resources necessary to model this large system. Process modeling will help move this technology from the bench-top to an industrial process. Applications at LLNL include rapid prototyping of metal parts and manufacturing new alloys by co-jetting different metals.

  20. 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.

  1. High precision beam alignment of electromagnetic wigglers

    SciTech Connect

    Ben-Zvi, I.; Qiu, X.Z.

    1993-01-01

    The performance of Free-Electron Lasers depends critically on the quality of the alignment of the electron beam to the wiggler's magnetic axis and the deviation of this axis from a straight fine. The measurement of the electron beam position requires numerous beam position monitors in the wiggler, where space is at premium. The beam position measurement is used to set beam steerers for an orbit correction in the wiggler. The authors propose an alternative high precision alignment method in which one or two external Beam Position Monitors (BPM) are used. In this technique, the field in the electro-wiggler is modulated section by section and the beam position movement at the external BPM is detected in synchronism with the modulation. A beam offset at the modulated beam section will produce a modulation of the beam position at the detector that is a function of the of the beam offset and the absolute value of the modulation current. The wiggler errors produce a modulation that is a function of the modulation current. It will be shown that this method allows the detection and correction of the beam position at each section in the presence of wiggler errors with a good resolution. Furthermore, it allows one to measure the first and second integrals of the wiggler error over each wiggler section. Lastly, provided that wiggler sections can be degaussed effectively, one can test the deviation of the wiggler's magnetic axis from a straight line.

  2. High-torque precision stepping drive

    NASA Technical Reports Server (NTRS)

    Kaspareck, W. E.

    1968-01-01

    Stepping drive has been designed for precise incremental angular positioning of scale models of spacecraft about a horizontal axis in order to accurately measure antenna receiving and transmitting characteristics. Positioning is insured by spring-loaded, self-locking plungers.

  3. 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.

  4. Distributed high-precision time transfer through passive optical networks

    NASA Astrophysics Data System (ADS)

    Wu, Guiling; Hu, Liang; Zhang, Hao; Chen, Jianping

    2014-09-01

    We propose a one-point to multipoint distributed time transfer through passive optical networks using a time division multiple access (TDMA) based two-way time transfer. The clock at each clock user node is, in turn, compared with the high-precision reference clock at a master node by a two-way time transfer during assigned subperiods. The corresponding TDMA control protocol and time transfer units for the proposed scheme are designed and implemented. A 1×8 experimental system with a 20 km single-mode fiber in each subpath is demonstrated. The results show that a standard deviation of <60 ps can be reached in each comparison subperiod.

  5. 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.

  6. 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.

  7. 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

    2014-07-01

    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.

  8. Simulations for the NIFFTE High Precision TPC

    NASA Astrophysics Data System (ADS)

    Thornton, Remington

    2010-10-01

    The Neutron Induced Fission Fragment Tracking Experiment has designed a Time Projection Chamber (TPC) to measure neutron induced fission cross-section measurements of the major actinides to sub-1% precision over a wide incident neutron energy range. These measurements are necessary to design the next generation of nuclear power plants. In order to design a TPC capable of making these measurements, a precise simulation was required to ensure better track reconstruction. Using the Geometry And Tracking (Geant4) simulation platform along with standalone code, a complete simulation package has been written. Asynchronous trigger, 3-D charge diffusion, capacitive charge sharing, digitization, random trigger cells, and noise from the electronics have been modeled inside the detector response simulation, along with code that generates bi-products of fission events for Geant4. This talk will discuss the current status and future planned developments of this work including the efforts to make this code reusable for future TPC projects.

  9. High Precision Noise Measurements at Microwave Frequencies

    SciTech Connect

    Ivanov, Eugene; Tobar, Michael

    2009-04-23

    We describe microwave noise measurement system capable of detecting the phase fluctuations of rms amplitude of 2{center_dot}10{sup -11} rad/{radical}(Hz). Such resolution allows the study of intrinsic fluctuations in various microwave components and materials, as well as precise tests of fundamental physics. Employing this system we discovered a previously unknown phenomenon of down-conversion of pump oscillator phase noise into the low-frequency voltage fluctuations.

  10. High-precision positioning of radar scatterers

    NASA Astrophysics Data System (ADS)

    Dheenathayalan, Prabu; Small, David; Schubert, Adrian; Hanssen, Ramon F.

    2016-05-01

    Remote sensing radar satellites cover wide areas and provide spatially dense measurements, with millions of scatterers. Knowledge of the precise position of each radar scatterer is essential to identify the corresponding object and interpret the estimated deformation. The absolute position accuracy of synthetic aperture radar (SAR) scatterers in a 2D radar coordinate system, after compensating for atmosphere and tidal effects, is in the order of centimeters for TerraSAR-X (TSX) spotlight images. However, the absolute positioning in 3D and its quality description are not well known. Here, we exploit time-series interferometric SAR to enhance the positioning capability in three dimensions. The 3D positioning precision is parameterized by a variance-covariance matrix and visualized as an error ellipsoid centered at the estimated position. The intersection of the error ellipsoid with objects in the field is exploited to link radar scatterers to real-world objects. We demonstrate the estimation of scatterer position and its quality using 20 months of TSX stripmap acquisitions over Delft, the Netherlands. Using trihedral corner reflectors (CR) for validation, the accuracy of absolute positioning in 2D is about 7 cm. In 3D, an absolute accuracy of up to ˜ 66 cm is realized, with a cigar-shaped error ellipsoid having centimeter precision in azimuth and range dimensions, and elongated in cross-range dimension with a precision in the order of meters (the ratio of the ellipsoid axis lengths is 1/3/213, respectively). The CR absolute 3D position, along with the associated error ellipsoid, is found to be accurate and agree with the ground truth position at a 99 % confidence level. For other non-CR coherent scatterers, the error ellipsoid concept is validated using 3D building models. In both cases, the error ellipsoid not only serves as a quality descriptor, but can also help to associate radar scatterers to real-world objects.

  11. High-precision triangular-waveform generator

    DOEpatents

    Mueller, T.R.

    1981-11-14

    An ultra-linear ramp generator having separately programmable ascending and decending ramp rates and voltages is provided. Two constant current sources provide the ramp through an integrator. Switching of the current at current source inputs rather than at the integrator input eliminates switching transients and contributes to the waveform precision. The triangular waveforms produced by the waveform generator are characterized by accurate reproduction and low drift over periods of several hours. The ascending and descending slopes are independently selectable.

  12. High precision fabrication of antennas and sensors

    NASA Astrophysics Data System (ADS)

    Balčytis, A.; Seniutinas, G.; Urbonas, D.; Gabalis, M.; Vaškevičius, K.; Petruškevičius, R.; Molis, G.; Valušis, G. `.; Juodkazis, S.

    2015-02-01

    Electron and ion beam lithographies were used to fabricate and/or functionalize large scale - millimetre footprint - micro-optical elements: coupled waveguide-resonator structures on silicon-on-insulator (SOI) and THz antennas on low temperature grown LT-GaAs. Waveguide elements on SOI were made without stitching errors using a fixed beam moving stage approach. THz antennas were created using a three-step litography process. First, gold THz antennas defined by standard mask projection lithography were annealed to make an ohmic contact on LT-GaAs and post-processing with Ga-ion beam was used to define nano-gaps and inter digitised contacts for better charge collection. These approaches show the possibility to fabricate large footprint patterns with nanoscale precision features and overlay accuracy. Emerging 3D nanofabrication trends are discussed.

  13. 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.

  14. Precision Timing Calorimeter for High Energy Physics

    DOE PAGESBeta

    Anderson, Dustin; Apresyan, Artur; Bornheim, Adolf; Duarte, Javier; Pena, Cristian; Ronzhin, Anatoly; Spiropulu, Maria; Trevor, Jason; Xie, Si

    2016-04-01

    Here, we present studies on the performance and characterization of the time resolution of LYSO-based calorimeters. Results for an LYSO sampling calorimeter and an LYSO-tungsten Shashlik calorimeter are presented. We also demonstrate that a time resolution of 30 ps is achievable for the LYSO sampling calorimeter. Timing calorimetry is described as a tool for mitigating the effects due to the large number of simultaneous interactions in the high luminosity environment foreseen for the Large Hadron Collider.

  15. High precision mass measurements for wine metabolomics

    NASA Astrophysics Data System (ADS)

    Roullier-Gall, Chloé; Witting, Michael; Gougeon, Régis; Schmitt-Kopplin, Philippe

    2014-11-01

    An overview of the critical steps for the non-targeted Ultra-High Performance Liquid Chromatography coupled with Quadrupole Time-of-Flight Mass Spectrometry (UPLC-Q-ToF-MS) analysis of wine chemistry is given, ranging from the study design, data preprocessing and statistical analyses, to markers identification. UPLC-Q-ToF-MS data was enhanced by the alignment of exact mass data from FTICR-MS, and marker peaks were identified using UPLC-Q-ToF-MS². In combination with multivariate statistical tools and the annotation of peaks with metabolites from relevant databases, this analytical process provides a fine description of the chemical complexity of wines, as exemplified in the case of red (Pinot noir) and white (Chardonnay) wines from various geographic origins in Burgundy.

  16. High precision mass measurements for wine metabolomics

    PubMed Central

    Roullier-Gall, Chloé; Witting, Michael; Gougeon, Régis D.; Schmitt-Kopplin, Philippe

    2014-01-01

    An overview of the critical steps for the non-targeted Ultra-High Performance Liquid Chromatography coupled with Quadrupole Time-of-Flight Mass Spectrometry (UPLC-Q-ToF-MS) analysis of wine chemistry is given, ranging from the study design, data preprocessing and statistical analyses, to markers identification. UPLC-Q-ToF-MS data was enhanced by the alignment of exact mass data from FTICR-MS, and marker peaks were identified using UPLC-Q-ToF-MS2. In combination with multivariate statistical tools and the annotation of peaks with metabolites from relevant databases, this analytical process provides a fine description of the chemical complexity of wines, as exemplified in the case of red (Pinot noir) and white (Chardonnay) wines from various geographic origins in Burgundy. PMID:25431760

  17. Precision timing calorimeter for high energy physics

    NASA Astrophysics Data System (ADS)

    Anderson, Dustin; Apresyan, Artur; Bornheim, Adolf; Duarte, Javier; Peña, Cristián; Spiropulu, Maria; Trevor, Jason; Xie, Si; Ronzhin, Anatoly

    2016-07-01

    Scintillator based calorimeter technology is studied with the aim to achieve particle detection with a time resolution on the order of a few 10 ps for photons and electrons at energies of a few GeV and above. We present results from a prototype of a 1.4×1.4×11.4 cm3 sampling calorimeter cell consisting of tungsten absorber plates and Cerium-doped Lutetium Yttrium Orthosilicate (LYSO) crystal scintillator plates. The LYSO plates are read out with wave lengths shifting fibers which are optically coupled to fast photo detectors on both ends of the fibers. The measurements with electrons were performed at the Fermilab Test Beam Facility (FTBF) and the CERN SPS H2 test beam. In addition to the baseline setup plastic scintillation counter and a MCP-PMT were used as trigger and as a reference for a time of flight measurement (TOF). We also present measurements with a fast laser to further characterize the response of the prototype and the photo sensors. All data were recorded using a DRS4 fast sampling digitizer. These measurements are part of an R&D program whose aim is to demonstrate the feasibility of building a large scale electromagnetic calorimeter with a time resolution on the order of 10 ps, to be used in high energy physics experiments.

  18. Galvanometer deflection: a precision high-speed system.

    PubMed

    Jablonowski, D P; Raamot, J

    1976-06-01

    An X-Y galvanometer deflection system capable of high precision in a random access mode of operation is described. Beam positional information in digitized form is obtained by employing a Ronchi grating with a sophisticated optical detection scheme. This information is used in a control interface to locate the beam to the required precision. The system is characterized by high accuracy at maximum speed and is designed for operation in a variable environment, with particular attention placed on thermal insensitivity.

  19. Galvanometer deflection: a precision high-speed system.

    PubMed

    Jablonowski, D P; Raamot, J

    1976-06-01

    An X-Y galvanometer deflection system capable of high precision in a random access mode of operation is described. Beam positional information in digitized form is obtained by employing a Ronchi grating with a sophisticated optical detection scheme. This information is used in a control interface to locate the beam to the required precision. The system is characterized by high accuracy at maximum speed and is designed for operation in a variable environment, with particular attention placed on thermal insensitivity. PMID:20165203

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

    SciTech Connect

    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).

  1. Experimental Dynamic Characterization of a Reconfigurable Adaptive Precision Truss

    NASA Technical Reports Server (NTRS)

    Hinkle, J. D.; Peterson, L. D.

    1994-01-01

    The dynamic behavior of a reconfigurable adaptive truss structure with non-linear joints is investigated. The objective is to experimentally examine the effects of the local non-linearities on the global dynamics of the structure. Amplitude changes in the frequency response functions are measured at micron levels of motion. The amplitude and frequency variations of a number of modes indicate a non-linear Coulomb friction response. Hysteretic bifurcation behavior is also measured at an amplitude approximately equal to the specified free-play in the joint. Under the 1 g pre-load, however, the non-linearity was dominantly characteristic of Coulomb friction with little evidence of free-play stiffening.

  2. Measurements of experimental precision for trials with cowpea (Vigna unguiculata L. Walp.) genotypes.

    PubMed

    Teodoro, P E; Torres, F E; Santos, A D; Corrêa, A M; Nascimento, M; Barroso, L M A; Ceccon, G

    2016-01-01

    The aim of this study was to evaluate the suitability of statistics as experimental precision degree measures for trials with cowpea (Vigna unguiculata L. Walp.) genotypes. Cowpea genotype yields were evaluated in 29 trials conducted in Brazil between 2005 and 2012. The genotypes were evaluated with a randomized block design with four replications. Ten statistics that were estimated for each trial were compared using descriptive statistics, Pearson correlations, and path analysis. According to the class limits established, selective accuracy and F-test values for genotype, heritability, and the coefficient of determination adequately estimated the degree of experimental precision. Using these statistics, 86.21% of the trials had adequate experimental precision. Selective accuracy and the F-test values for genotype, heritability, and the coefficient of determination were directly related to each other, and were more suitable than the coefficient of variation and the least significant difference (by the Tukey test) to evaluate experimental precision in trials with cowpea genotypes. PMID:27173351

  3. Measurements of experimental precision for trials with cowpea (Vigna unguiculata L. Walp.) genotypes.

    PubMed

    Teodoro, P E; Torres, F E; Santos, A D; Corrêa, A M; Nascimento, M; Barroso, L M A; Ceccon, G

    2016-05-09

    The aim of this study was to evaluate the suitability of statistics as experimental precision degree measures for trials with cowpea (Vigna unguiculata L. Walp.) genotypes. Cowpea genotype yields were evaluated in 29 trials conducted in Brazil between 2005 and 2012. The genotypes were evaluated with a randomized block design with four replications. Ten statistics that were estimated for each trial were compared using descriptive statistics, Pearson correlations, and path analysis. According to the class limits established, selective accuracy and F-test values for genotype, heritability, and the coefficient of determination adequately estimated the degree of experimental precision. Using these statistics, 86.21% of the trials had adequate experimental precision. Selective accuracy and the F-test values for genotype, heritability, and the coefficient of determination were directly related to each other, and were more suitable than the coefficient of variation and the least significant difference (by the Tukey test) to evaluate experimental precision in trials with cowpea genotypes.

  4. 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.

  5. A Comparison of three high-precision quadrature schemes

    SciTech Connect

    Bailey, David H.; Li, Xiaoye S.

    2003-07-01

    The authors have implemented three numerical quadrature schemes, using the new Arbitrary Precision (ARPREC) software package, with the objective of seeking a completely ''automatic'' arbitrary precision quadrature facility, namely one that does not rely on a priori information of the function to be integrated. Such a facility is required, for example, to permit the experimental identification of definite integrals based on their numerical values. The performance and accuracy of these three quadrature schemes are compared using a suite of 15 integrals, ranging from continuous, well-behaved functions on finite intervals to functions with vertical derivatives and integrable singularities at endpoints, as well as several integrals on an infinite interval.

  6. An experimental search strategy retrieves more precise results than PubMed and Google for questions about medical interventions

    PubMed Central

    Dylla, Daniel P.; Megison, Susan D.

    2015-01-01

    Objective. We compared the precision of a search strategy designed specifically to retrieve randomized controlled trials (RCTs) and systematic reviews of RCTs with search strategies designed for broader purposes. Methods. We designed an experimental search strategy that automatically revised searches up to five times by using increasingly restrictive queries as long at least 50 citations were retrieved. We compared the ability of the experimental and alternative strategies to retrieve studies relevant to 312 test questions. The primary outcome, search precision, was defined for each strategy as the proportion of relevant, high quality citations among the first 50 citations retrieved. Results. The experimental strategy had the highest median precision (5.5%; interquartile range [IQR]: 0%–12%) followed by the narrow strategy of the PubMed Clinical Queries (4.0%; IQR: 0%–10%). The experimental strategy found the most high quality citations (median 2; IQR: 0–6) and was the strategy most likely to find at least one high quality citation (73% of searches; 95% confidence interval 68%–78%). All comparisons were statistically significant. Conclusions. The experimental strategy performed the best in all outcomes although all strategies had low precision. PMID:25922798

  7. 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.

  8. 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%.

  9. High precision predictions for exclusive VH production at the LHC

    DOE PAGESBeta

    Li, Ye; Liu, Xiaohui

    2014-06-04

    We present a resummation-improved prediction for pp → VH + 0 jets at the Large Hadron Collider. We focus on highly-boosted final states in the presence of jet veto to suppress the tt¯ background. In this case, conventional fixed-order calculations are plagued by the existence of large Sudakov logarithms αnslogm(pvetoT/Q) for Q ~ mV + mH which lead to unreliable predictions as well as large theoretical uncertainties, and thus limit the accuracy when comparing experimental measurements to the Standard Model. In this work, we show that the resummation of Sudakov logarithms beyond the next-to-next-to-leading-log accuracy, combined with the next-to-next-to-leading ordermore » calculation, reduces the scale uncertainty and stabilizes the perturbative expansion in the region where the vector bosons carry large transverse momentum. Thus, our result improves the precision with which Higgs properties can be determined from LHC measurements using boosted Higgs techniques.« less

  10. 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.

  11. Yale High Energy Physics Research: Precision Studies of Reactor Antineutrinos

    SciTech Connect

    Heeger, Karsten M.

    2014-09-13

    This report presents experimental research at the intensity frontier of particle physics with particular focus on the study of reactor antineutrinos and the precision measurement of neutrino oscillations. The experimental neutrino physics group of Professor Heeger and Senior Scientist Band at Yale University has had leading responsibilities in the construction and operation of the Daya Bay Reactor Antineutrino Experiment and made critical contributions to the discovery of non-zero$\\theta_{13}$. Heeger and Band led the Daya Bay detector management team and are now overseeing the operations of the antineutrino detectors. Postdoctoral researchers and students in this group have made leading contributions to the Daya Bay analysis including the prediction of the reactor antineutrino flux and spectrum, the analysis of the oscillation signal, and the precision determination of the target mass yielding unprecedented precision in the relative detector uncertainty. Heeger's group is now leading an R\\&D effort towards a short-baseline oscillation experiment, called PROSPECT, at a US research reactor and the development of antineutrino detectors with advanced background discrimination.

  12. High channel count and high precision channel spacing multi-wavelength laser array for future PICs

    NASA Astrophysics Data System (ADS)

    Shi, Yuechun; Li, Simin; Chen, Xiangfei; Li, Lianyan; Li, Jingsi; Zhang, Tingting; Zheng, Jilin; Zhang, Yunshan; Tang, Song; Hou, Lianping; Marsh, John H.; Qiu, Bocang

    2014-12-01

    Multi-wavelength semiconductor laser arrays (MLAs) have wide applications in wavelength multiplexing division (WDM) networks. In spite of their tremendous potential, adoption of the MLA has been hampered by a number of issues, particularly wavelength precision and fabrication cost. In this paper, we report high channel count MLAs in which the wavelengths of each channel can be determined precisely through low-cost standard μm-level photolithography/holographic lithography and the reconstruction-equivalent-chirp (REC) technique. 60-wavelength MLAs with good wavelength spacing uniformity have been demonstrated experimentally, in which nearly 83% lasers are within a wavelength deviation of +/-0.20 nm, corresponding to a tolerance of +/-0.032 nm in the period pitch. As a result of employing the equivalent phase shift technique, the single longitudinal mode (SLM) yield is nearly 100%, while the theoretical yield of standard DFB lasers is only around 33.3%.

  13. 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

  14. 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.

  15. 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.

  16. Precision glass molding of high-resolution diffractive optical elements

    NASA Astrophysics Data System (ADS)

    Prater, Karin; Dukwen, Julia; Scharf, Toralf; Herzig, Hans P.; Plöger, Sven; Hermerschmidt, Andreas

    2016-04-01

    The demand of high resolution diffractive optical elements (DOE) is growing. Smaller critical dimensions allow higher deflection angles and can fulfill more demanding requirements, which can only be met by using electron-beam lithography. Replication techniques are more economical, since the high cost of the master can be distributed among a larger number of replicas. The lack of a suitable mold material for precision glass molding has so far prevented an industrial use. Glassy Carbon (GC) offers a high mechanical strength and high thermal strength. No anti-adhesion coatings are required in molding processes. This is clearly an advantage for high resolution, high aspect ratio microstructures, where a coating with a thickness between 10 nm and 200 nm would cause a noticeable rounding of the features. Electron-beam lithography was used to fabricate GC molds with highest precision and feature sizes from 250 nm to 2 μm. The master stamps were used for precision glass molding of a low Tg glass L-BAL42 from OHARA. The profile of the replicated glass is compared to the mold with the help of SEM images. This allows discussion of the max. aspect-ratio and min. feature size. To characterize optical performances, beamsplitting elements are fabricated and their characteristics were investigated, which are in excellent agreement to theory.

  17. A novel power source for high-precision, highly efficient micro w-EDM

    NASA Astrophysics Data System (ADS)

    Chen, Shun-Tong; Chen, Chi-Hung

    2015-07-01

    The study presents the development of a novel power source for high-precision, highly efficient machining of micropart microstructures using micro wire electrical discharge machining (w-EDM). A novel power source based on a pluri resistance-capacitance (pRC) circuit that can generate a high-frequency, high-peak current with a short pulse train is proposed and designed to enhance the performance of micro w-EDM processes. Switching between transistors is precisely controlled in the designed power source to create a high-frequency short-pulse train current. Various microslot cutting tests in both aluminum and copper alloys are conducted. Experimental results demonstrate that the pRC power source creates instant spark erosion resulting in markedly less material for removal, diminishing discharge crater size, and consequently an improved surface finish. A new evaluation approach for spark erosion ability (SEA) to assess the merits of micro EDM power sources is also proposed. In addition to increasing the speed of micro w-EDM by increasing wire feed rates by 1.6 times the original feed rate, the power source is more appropriate for machining micropart microstructures since there is less thermal breaking. Satisfactory cutting of an elaborate miniature hook-shaped structure and a high-aspect ratio microstructure with a squared-pillar array also reveal that the developed pRC power source is effective, and should be very useful in the manufacture of intricate microparts.

  18. 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.

  19. Experimental and numerical analysis of thermal forming processes for precision optics

    NASA Astrophysics Data System (ADS)

    Su, Lijuan

    Glass has been fabricated into different optical elements including aspherical lenses and freeform mirrors. However, aspherical lenses are very difficult to manufacture using traditional methods since they were specially developed for spherical lenses. On the other hand, large size mirrors are also difficult to make especially for high precision applications or if designed with complicated shapes. Recently developed two closely related thermal forming processes, i.e. compression molding and thermal slumping, have emerged as two promising methods for manufacturing aspherical lenses and freeform mirrors efficiently. Compression molding has already been used in industry to fabricate consumer products such as the lenses for digital cameras, while thermal slumping has been aggressively tested to create x-ray mirrors for space-based telescopes as well as solar panels. Although both process showed great potentials, there are a quite few technical challenges that prevent them from being readily implemented in industry for high volume production. This dissertation research seeks a fundamental understanding of the thermal forming processes for both precision glass lenses and freeform mirrors by using a combined experimental, analytical and numerical modeling approach. First, a finite element method (FEM) based methodology was presented to predict the refractive index change of glass material occurred during cooling. The FEM prediction was then validated using experimental results. Second, experiments were also conducted on glass samples with different cooling rates to study the refractive index variation caused by non-uniform cooling. A Shack-Hartmann Sensor (SHS) test setup was built to measure the index variations of thermally treated glass samples. Again, an FEM simulation model was developed to predict the refractive index variation. The prediction was compared with the experimental result, and the effects of different parameters were evaluated. In the last phase of this

  20. 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.

  1. Slow Control System for the NIFFTE High Precision TPC

    NASA Astrophysics Data System (ADS)

    Thornton, Remington

    2010-11-01

    The Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) has designed a Time Projection Chamber (TPC) to measure neutron induced fission cross-section measurements of the major actinides to sub-1% precision over a wide incident neutron energy range. These measurements are necessary to design the next generation of nuclear power plants. In order to achieve our high precision goals, an accurate and efficient slow control system must be implemented. Custom software has been created to control the hardware through Maximum Integration Data Acquisition System (MIDAS). This includes reading room and device temperature, setting the high voltage power supplies, and reading voltages. From hardware to software, an efficient design has been implemented and tested. This poster will present the setup and data from this slow control system.

  2. Strategy for Realizing High-Precision VUV Spectro-Polarimeter

    NASA Astrophysics Data System (ADS)

    Ishikawa, R.; Narukage, N.; Kubo, M.; Ishikawa, S.; Kano, R.; Tsuneta, S.

    2014-12-01

    Spectro-polarimetric observations in the vacuum ultraviolet (VUV) range are currently the only means to measure magnetic fields in the upper chromosphere and transition region of the solar atmosphere. The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) aims to measure linear polarization at the hydrogen Lyman- α line (121.6 nm). This measurement requires a polarization sensitivity better than 0.1 %, which is unprecedented in the VUV range. We here present a strategy with which to realize such high-precision spectro-polarimetry. This involves the optimization of instrument design, testing of optical components, extensive analyses of polarization errors, polarization calibration of the instrument, and calibration with onboard data. We expect that this strategy will aid the development of other advanced high-precision polarimeters in the UV as well as in other wavelength ranges.

  3. 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.

  4. 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

  5. OPTIMIZING THE PRECISION OF TOXICITY THRESHOLD ESTIMATION USING A TWO-STAGE EXPERIMENTAL DESIGN

    EPA Science Inventory

    An important consideration for risk assessment is the existence of a threshold, i.e., the highest toxicant dose where the response is not distinguishable from background. We have developed methodology for finding an experimental design that optimizes the precision of threshold mo...

  6. Some comments on high precision study of neutrino oscillations

    NASA Astrophysics Data System (ADS)

    Bilenky, S. M.

    2015-07-01

    I discuss here some problems connected with the high precision study of neutrino oscillations. In the general case of n-neutrino mixing I derive a convenient expression for transition probability in which only independent terms (and mass-squared differences) enter. For three-neutrino mixing I discuss a problem of a definition of a large (atmospheric) neutrino mass-squared difference. I comment also possibilities to reveal the character of neutrino mass spectrum in future reactor neutrino experiments.

  7. High precision tide spectroscopy. [using the superconducting gravimeter

    NASA Technical Reports Server (NTRS)

    Goodkind, J. M.

    1978-01-01

    Diurnal and long period earth tides were measured to high accuracy and precision with the superconducting gravimeter. The results provide new evidence on the geophysical questions which have been attacked through earth tide measurements in the past. In addition, they raise new questions of potential interest. Slow fluctuations in gravity of order 10 micron gal over periods of 3 to 5 months were observed and are discussed.

  8. High precision metrology of domes and aspheric optics

    NASA Astrophysics Data System (ADS)

    Murphy, Paul E.; Fleig, Jon; Forbes, Greg; Tricard, Marc

    2005-05-01

    Many defense systems have a critical need for high-precision, complex optics. However, fabrication of high quality, advanced optics is often seriously hampered by the lack of accurate and affordable metrology. QED's Subaperture Stitching Interferometer (SSI®) provides a breakthrough technology, enabling the automatic capture of precise metrology data for large and/or strongly curved (concave and convex) parts. QED"s SSI complements next-generation finishing technologies, such as Magnetorheological Finishing (MRF®), by extending the effective aperture, accuracy and dynamic range of a phase-shifting interferometer. This workstation performs automated sub-aperture stitching measurements of spheres, flats, and mild aspheres. It combines a six-axis precision stage system, a commercial Fizeau interferometer, and specially developed software that automates measurement design, data acquisition, and the reconstruction of the full-aperture figure error map. Aside from the correction of sub-aperture placement errors (such as tilts, optical power, and registration effects), our software also accounts for reference-wave error, distortion and other aberrations in the interferometer"s imaging optics. The SSI can automatically measure the full aperture of high numerical aperture surfaces (such as domes) to interferometric accuracy. The SSI extends the usability of a phase measuring interferometer and allows users with minimal training to produce full-aperture measurements of otherwise untestable parts. Work continues to extend this technology to measure aspheric shapes without the use of dedicated null optics. This SSI technology will be described, sample measurement results shown, and various manufacturing applications discussed.

  9. 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.

  10. Photonic systems for high precision radial velocity measurements

    NASA Astrophysics Data System (ADS)

    Halverson, Samuel

    2016-01-01

    I will discuss new instrumentation and techniques designed to maximize the Doppler radial velocity (RV) measurement precision of next generation exoplanet discovery instruments. These systems include a novel wavelength calibration device based on an all-fiber fabry-perot interferometer, a compact and efficient optical fiber image scrambler based on a single high-index ball lens, and a unique optical fiber mode mixer. These systems have been developed specifically to overcome three technological hurdles that have classically hindered high precision RV measurements in both the optical and near-infrared (NIR), namely: lack of available wavelength calibration sources, inadequate decoupling of the spectrograph from variable telescope illumination, and speckle-induced noise due to mode interference in optical fibers. The instrumentation presented here will be applied to the Habitable-zone Planet Finder, a NIR RV instrument designed to detect rocky planets orbiting in the habitable zones of nearby M-dwarfs, and represents a critical technological step towards the detection of potentially habitable Earth-like planets. While primarily focused in the NIR, many of these systems will be adapted to future optical RV instruments as well, such as NASA's new Extreme Precision Doppler Spectrometer for the WIYN telescope.

  11. 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.

  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. High Precision Polarimetry of the Epsilon Aurigae Eclipse

    NASA Astrophysics Data System (ADS)

    Wiktorowicz, Sloane

    2013-07-01

    Polarimetry of the epsilon Aurigae eclipse has the potential to discern the stellar latitude occulted by the companion's dusty disk, which may directly test interferometric results. In addition, the limb polarization of the primary star may be measured, which is an effect predicted by S. Chandrasekhar and verified by spatially resolved observations of the Sun. I will present B band, polarimetric observations of epsilon Aurigae taken over six nights in September and October 2009 using the POLISH high precision polarimeter at the Lick 3-m telescope. Polarimetric precision achieved during each night is of order 1 part in 10^5. Extensive post-eclipse observations have been taken with the significantly upgraded POLISH2 polarimeter at Lick Observatory. This instrument simultaneously measures all four Stokes parameters (I, Q, U, and V) and achieves precision within 2.0 times the photon shot noise limit over an entire observing run. This work is supported by a NExScI Sagan Fellowship, UC Lab Fees Research Grant, and UCO/Lick Observatory.

  14. High Resolution, High Precision I-Line Stepper Processing

    NASA Astrophysics Data System (ADS)

    Yanazawa, H.; Hasegawa, N.; Kurosaki, T.; Hashimoto, N.; Nonogaki, S.

    1985-06-01

    Currently, the integrated MOS dynamic RAM has as many as 256 thousand memory cells per chip based on 2 pm photolithography. Figure 1 shows the history and the prospects for progress in microfabrication technology. Feature size versus year, as reported by Bossung in 1978, is shown, as developed from independent analysis by Moore, Noyce and Gnostic concept. Circles numbered 1 and 2 show that 64K- and 256K-bit RAMs were developed in 1981 and 1984, and that their feature sizes were 3μm and 2μm, respectively. It is significant that the predictions and the real developments are so close. Furthermore, since the basic process for 3 M-bit RAMs based on 1.3μm microlithography has already been reported in conference, it is highly likely that they will become commercially available around 1987, as predicted by the circle numbered 3 based on 1.3μm microlithography.

  15. Globular Cluster Streams as Galactic High-Precision Scales

    NASA Astrophysics Data System (ADS)

    Küpper, Andreas H. W.; Balbinot, Eduardo; Bonaca, Ana; Johnston, Kathryn V.; Hogg, David W.; Kroupa, Pavel; Santiago, Basilio X.

    2016-08-01

    Tidal streams of globular clusters are ideal tracers of the Galactic gravitational potential. Compared to the few known, complex and diffuse dwarf-galaxy streams, they are kinematically cold, have thin morphologies and are abundant in the halo of the Milky Way. Their coldness and thinness in combination with potential epicyclic substructure in the vicinity of the stream progenitor turns them into high-precision scales. With the example of Palomar 5, we demonstrate how modeling of a globular cluster stream allows us to simultaneously measure the properties of the disrupting globular cluster, its orbital motion, and the gravitational potential of the Milky Way.

  16. High-Precision Motorcycle Trajectory Measurements Using GPS

    NASA Astrophysics Data System (ADS)

    Koyama, Yuichiro; Tanaka, Toshiyuki

    A method for measuring motorcycle trajectory using GPS is needed for simulating motorcycle dynamics. In GPS measurements of a motorcycle, both the declination of the motorcycle and obstacles near the course can cause problems. Therefore, we propose a new algorithm for GPS measurement of motorcycle trajectory. We interpolate the missing observation data within a few seconds using polynomial curves, and use a Kalman filter to smoothen position calculations. This results in obtaining trajectory with high accuracy and with sufficient continuity. The precision is equal to that of fixed point positioning, given a sufficient number of available satellites.

  17. 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.

  18. 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.

  19. Experimental study on the precise orbit determination of the BeiDou navigation satellite system.

    PubMed

    He, Lina; Ge, Maorong; Wang, Jiexian; Wickert, Jens; Schuh, Harald

    2013-01-01

    The regional service of the Chinese BeiDou satellite navigation system is now in operation with a constellation including five Geostationary Earth Orbit satellites (GEO), five Inclined Geosynchronous Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Besides the standard positioning service with positioning accuracy of about 10 m, both precise relative positioning and precise point positioning are already demonstrated. As is well known, precise orbit and clock determination is essential in enhancing precise positioning services. To improve the satellite orbits of the BeiDou regional system, we concentrate on the impact of the tracking geometry and the involvement of MEOs, and on the effect of integer ambiguity resolution as well. About seven weeks of data collected at the BeiDou Experimental Test Service (BETS) network is employed in this experimental study. Several tracking scenarios are defined, various processing schemata are designed and carried out; and then, the estimates are compared and analyzed in detail. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. The involvement of MEOs and ambiguity-fixing also make the orbits better.

  20. 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

  1. A High Precision Terahertz Wave Image Reconstruction Algorithm.

    PubMed

    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

  2. Effects of experimental design on calibration curve precision in routine analysis.

    PubMed

    Pimentel, M F; Neto, B de B; Saldanha, T C; Araújo, M C

    1998-01-01

    A computational program which compares the effciencies of different experimental designs with those of maximum precision (D-optimized designs) is described. The program produces confidence interval plots for a calibration curve and provides information about the number of standard solutions, concentration levels and suitable concentration ranges to achieve an optimum calibration. Some examples of the application of this novel computational program are given, using both simulated and real data.

  3. High precision Hugoniot measurements of D2 near maximum compression

    NASA Astrophysics Data System (ADS)

    Benage, John; Knudson, Marcus; Desjarlais, Michael

    2015-11-01

    The Hugoniot response of liquid deuterium has been widely studied due to its general importance and to the significant discrepancy in the inferred shock response obtained from early experiments. With improvements in dynamic compression platforms and experimental standards these results have converged and show general agreement with several equation of state (EOS) models, including quantum molecular dynamics (QMD) calculations within the Generalized Gradient Approximation (GGA). This approach to modeling the EOS has also proven quite successful for other materials and is rapidly becoming a standard approach. However, small differences remain among predictions obtained using different local and semi-local density functionals; these small differences show up in the deuterium Hugoniot at ~ 30-40 GPa near the region of maximum compression. Here we present experimental results focusing on that region of the Hugoniot and take advantage of advancements in the platform and standards, resulting in data with significantly higher precision than that obtained in previous studies. These new data may prove to distinguish between the subtle differences predicted by the various density functionals. Results of these experiments will be presented along with comparison to various QMD calculations. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin company, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  4. Selection and use of TLDS for high precision NERVA shielding measurements

    NASA Technical Reports Server (NTRS)

    Woodsum, H. C.

    1972-01-01

    An experimental evaluation of thermoluminescent dosimeters was performed in order to select high precision dosimeters for a study whose purpose is to measure gamma streaming through the coolant passages of a simulated flight type internal NERVA reactor shield. Based on this study, the CaF2 chip TLDs are the most reproducible dosimeters with reproducibility generally within a few percent, but none of the TLDs tested met the reproducibility criterion of plus or minus 2%.

  5. 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

  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. High precision measurement of electrical resistance across endothelial cell monolayers.

    PubMed

    Tschugguel, W; Zhegu, Z; Gajdzik, L; Maier, M; Binder, B R; Graf, J

    1995-05-01

    Effects of vasoactive agonists on endothelial permeability was assessed by measurement of transendothelial electrical resistance (TEER) of human umbilical vein endothelial cells (HUVECs) grown on porous polycarbonate supports. Because of the low values of TEER obtained in this preparation (< 5 omega cm2) a design of an Ussing type recording chamber was chosen that provided for a homogeneous electric field across the monolayer and for proper correction of series resistances. Precision current pulses and appropriate rates of sampling and averaging of the voltage signal allowed for measurement of < 0.1 omega resistance changes of the endothelium on top of a 21 omega series resistance of the support and bathing fluid layers. Histamine (10 microM) and thrombin (10 U/ml) induced an abrupt and substantial decrease of TEER, bradykinin (1 microM) was less effective, PAF (380 nM) and LTC4 (1 microM) had no effect. TEER was also reduced by the calcium ionophore A-23187 (10 microM). The technique allows for measurements of TEER in low resistance monolayer cultures with high precision and time resolution. The results obtained extend previous observations in providing quantitative data on the increase of permeability of HUVECs in response to vasoactive agonists.

  8. 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

  9. Simultaneous Precision Gravimetry and Magnetic Gradiometry with a Bose-Einstein Condensate: A High Precision, Quantum Sensor

    NASA Astrophysics Data System (ADS)

    Hardman, K. S.; Everitt, P. J.; McDonald, G. D.; Manju, P.; Wigley, P. B.; Sooriyabandara, M. A.; Kuhn, C. C. N.; Debs, J. E.; Close, J. D.; Robins, N. P.

    2016-09-01

    A Bose-Einstein condensate is used as an atomic source for a high precision sensor. A 5 ×1 06 atom F =1 spinor condensate of 87Rb is released into free fall for up to 750 ms and probed with a T =130 ms Mach-Zehnder atom interferometer based on Bragg transitions. The Bragg interferometer simultaneously addresses the three magnetic states |mf=1 ,0 ,-1 ⟩, facilitating a simultaneous measurement of the acceleration due to gravity with a 1000 run precision of Δ g /g =1.45 ×10-9 and the magnetic field gradient to a precision of 120 pT /m .

  10. Suppression of radiation damping for high precision quantitative NMR

    NASA Astrophysics Data System (ADS)

    Bayle, Kevin; Julien, Maxime; Remaud, Gérald S.; Akoka, Serge

    2015-10-01

    True quantitative analysis of concentrated samples by 1H NMR is made very difficult by Radiation Damping. A novel NMR sequence (inspired by the WET NMR sequence and by Outer Volume Saturation methods) is therefore proposed to suppress this phenomenon by reducing the spatial area and consequently the number of spins contributing to the signal detected. The size of the detected volume can be easily chosen in a large range and line shape distortions are avoided thanks to a uniform signal suppression of the outer volume. Composition of a mixture can as a result be determined with very high accuracy (precision and trueness) at the per mille level whatever the concentrations and without hardware modification.

  11. 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.

  12. Precision Viticulture from Multitemporal, Multispectral Very High Resolution Satellite Data

    NASA Astrophysics Data System (ADS)

    Kandylakis, Z.; Karantzalos, K.

    2016-06-01

    In order to exploit efficiently very high resolution satellite multispectral data for precision agriculture applications, validated methodologies should be established which link the observed reflectance spectra with certain crop/plant/fruit biophysical and biochemical quality parameters. To this end, based on concurrent satellite and field campaigns during the veraison period, satellite and in-situ data were collected, along with several grape samples, at specific locations during the harvesting period. These data were collected for a period of three years in two viticultural areas in Northern Greece. After the required data pre-processing, canopy reflectance observations, through the combination of several vegetation indices were correlated with the quantitative results from the grape/must analysis of grape sampling. Results appear quite promising, indicating that certain key quality parameters (like brix levels, total phenolic content, brix to total acidity, anthocyanin levels) which describe the oenological potential, phenolic composition and chromatic characteristics can be efficiently estimated from the satellite data.

  13. High-precision digital charge-coupled device TV system

    NASA Astrophysics Data System (ADS)

    Vishnevsky, Grigory I.; Ioffe, S. A.; Berezin, V. Y.; Rybakov, M. I.; Mikhaylov, A. V.; Belyaev, L. V.

    1991-06-01

    In certain test, measurement, and research applications of CCD TV systems, the greater accuracy than usual 8-bit frame-grabbers can provide is demanded without the system being too expensive. The paper presents the concept and features of the high-precision low-cost digital CCD TV system intended for obtaining 12-bit monochrome images of immobile or relatively slow moving objects. The increase in accuracy is achieved by the specific digitization procedure -- one column per frame, which combines the benefits of a slow A/D converter with real-time TV imaging compatibility. To reduce speed restrictions on sample- and-hold circuits, a zoomed pixel read out cycle, corresponding to the pixel to be digitized, is proposed. The system provides great flexibility in choice of integration times and readout rates by means of a programmable readout sequencer, and is easily adaptable to various user demands and CCDs types.

  14. Ultra High Precision Laser Monitor for Oxygen Eddy Flux Measurements

    NASA Astrophysics Data System (ADS)

    Nelson, David; Herndon, Scott; McManus, Barry; Roscioli, Rob; Jervis, Dylan; Zahniser, Mark

    2016-04-01

    Atmospheric oxygen provides one of the most powerful tracers to study the carbon cycle through its close interaction with carbon dioxide. Keeling and co-workers demonstrated this at the global scale by using small variations in atmospheric oxygen content to disentangle oceanic and terrestrial carbon sinks. It would be very exciting to apply similar ideas at the ecosystem level to improve our understanding of biosphere-atmosphere exchange and our ability to predict the response of the biosphere and atmosphere to climate change. The eddy covariance technique is perhaps the most effective approach available to quantify the exchange of gases between these spheres. Therefore, eddy covariance flux measurements of oxygen would be extremely valuable. However, this requires a fast response (0.1 seconds), high relative precision (0.001% or 10 per meg) oxygen sensor. We report recent progress in developing such a sensor using a high resolution visible laser to probe the oxygen A-band electronic transition. We have demonstrated precision of 1 ppmv or 5 per meg for a 100 second measurement duration. This sensor will enable oxygen flux measurements using eddy covariance. In addition, we will incorporate a second laser in this instrument to simultaneously determine the fluxes of oxygen, carbon dioxide and water vapor within the same sampling cell. This will provide a direct, real time measurement of the ratio of the flux of oxygen to that of carbon dioxide. This ratio is expected to vary on short time scales and small spatial scales due to the differing stoichiometry of processes producing and consuming carbon dioxide. Thus measuring the variations in the ratio of oxygen and carbon dioxide fluxes will provide mechanistic information to improve our understanding of the crucial exchange of carbon between the atmosphere and biosphere.

  15. 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.

  16. High-precision baseband timing of 15 millisecond pulsars

    NASA Astrophysics Data System (ADS)

    Hotan, A. W.; Bailes, M.; Ord, S. M.

    2006-07-01

    We describe extremely precise timing experiments performed on five solitary and 10 binary millisecond pulsars during the past 3 yr, with the Caltech Parkes Swinburne Recorder (CPSR2) coherent dedispersion system at the Parkes 64-m radio telescope. 12 of our sources have rms timing residuals below 1.5μs and four are below 200ns. The quality of our data allows us to measure eight parallaxes and nine proper motions, from which we conclude that models of galactic electron density still have limited predictive power for individual objects. We derive a mean transverse velocity of 87+31/-14kms-1 for these pulsars, in good agreement with previous authors. We demonstrate that unless multifrequency observations are made, typical variations in dispersion measure (DM) could introduce an additional drift in arrival times of ~1μs per year at 20-cm wavelengths. Our high timing precision means that Shapiro delay can be used to constrain the inclination angles and component masses of all but two of the selected binary systems. The signature of annual orbital parallax is detected in the timing of PSR J0437-4715 and PSR J1713+0747, providing additional geometric constraints. The timing of PSR J1909-3744 is used to demonstrate that the DE405 ephemeris is a better model of the Solar system than the earlier DE200. In addition, we show that pulsar astrometric parameters measured using DE200 and DE405 often differ significantly. In order to use pulsars to search for a cosmological gravitational wave background, it is desirable to time them against each other to eliminate Earth-based time standards. We demonstrate that PSR J1909-3744 can be used as a reference against which we obtain a very small rms residual of 133ns for PSR J1713+0747. Although the gain of the Parkes antenna is small compared to other telescopes involved in precision timing, we obtain some of the lowest rms residuals ever measured, highlighting the importance of good instrumentation such as CPSR2 and good analysis

  17. Precision, high dose radiotherapy: helium ion treatment of uveal melanoma

    SciTech Connect

    Saunders, W.M.; Char, D.H.; Quivey, J.M.; Castro, J.R.; Chen, G.T.Y.; Collier, J.M.; Cartigny, A.; Blakely, E.A.; Lyman, J.T.; Zink, S.R.

    1985-02-01

    The authors report on 75 patients with uveal melanoma who were treated by placing the Bragg peak of a helium ion beam over the tumor volume. The technique localizes the high dose region very tightly around the tumor volume. This allows critical structures, such as the optic disc and the macula, to be excluded from the high dose region as long as they are 3 to 4 mm away from the edge of the tumor. Careful attention to tumor localization, treatment planning, patient immobilization and treatment verification is required. With a mean follow-up of 22 months (3 to 60 months) the authors have had only five patients with a local recurrence, all of whom were salvaged with another treatment. Pretreatment visual acuity has generally been preserved as long as the tumor edge is at least 4 mm away from the macula and optic disc. The only serious complication to date has been an 18% incidence of neovascular glaucoma in the patients treated at our highest dose level. Clinical results and details of the technique are presented to illustrate potential clinical precision in administering high dose radiotherapy with charged particles such as helium ions or protons.

  18. Evaluation of High-Precision Sensors in Structural Monitoring

    PubMed Central

    Erol, Bihter

    2010-01-01

    One of the most intricate branches of metrology involves the monitoring of displacements and deformations of natural and anthropogenic structures under environmental forces, such as tidal or tectonic phenomena, or ground water level changes. Technological progress has changed the measurement process, and steadily increasing accuracy requirements have led to the continued development of new measuring instruments. The adoption of an appropriate measurement strategy, with proper instruments suited for the characteristics of the observed structure and its environmental conditions, is of high priority in the planning of deformation monitoring processes. This paper describes the use of precise digital inclination sensors in continuous monitoring of structural deformations. The topic is treated from two viewpoints: (i) evaluation of the performance of inclination sensors by comparing them to static and continuous GPS observations in deformation monitoring and (ii) providing a strategy for analyzing the structural deformations. The movements of two case study objects, a tall building and a geodetic monument in Istanbul, were separately monitored using dual-axes micro-radian precision inclination sensors (inclinometers) and GPS. The time series of continuous deformation observations were analyzed using the Least Squares Spectral Analysis Technique (LSSA). Overall, the inclinometers showed good performance for continuous monitoring of structural displacements, even at the sub-millimeter level. Static GPS observations remained insufficient for resolving the deformations to the sub-centimeter level due to the errors that affect GPS signals. With the accuracy advantage of inclination sensors, their use with GPS provides more detailed investigation of deformation phenomena. Using inclinometers and GPS is helpful to be able to identify the components of structural responses to the natural forces as static, quasi-static, or resonant. PMID:22163499

  19. 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.

  20. Evaluation of high-precision sensors in structural monitoring.

    PubMed

    Erol, Bihter

    2010-01-01

    One of the most intricate branches of metrology involves the monitoring of displacements and deformations of natural and anthropogenic structures under environmental forces, such as tidal or tectonic phenomena, or ground water level changes. Technological progress has changed the measurement process, and steadily increasing accuracy requirements have led to the continued development of new measuring instruments. The adoption of an appropriate measurement strategy, with proper instruments suited for the characteristics of the observed structure and its environmental conditions, is of high priority in the planning of deformation monitoring processes. This paper describes the use of precise digital inclination sensors in continuous monitoring of structural deformations. The topic is treated from two viewpoints: (i) evaluation of the performance of inclination sensors by comparing them to static and continuous GPS observations in deformation monitoring and (ii) providing a strategy for analyzing the structural deformations. The movements of two case study objects, a tall building and a geodetic monument in Istanbul, were separately monitored using dual-axes micro-radian precision inclination sensors (inclinometers) and GPS. The time series of continuous deformation observations were analyzed using the Least Squares Spectral Analysis Technique (LSSA). Overall, the inclinometers showed good performance for continuous monitoring of structural displacements, even at the sub-millimeter level. Static GPS observations remained insufficient for resolving the deformations to the sub-centimeter level due to the errors that affect GPS signals. With the accuracy advantage of inclination sensors, their use with GPS provides more detailed investigation of deformation phenomena. Using inclinometers and GPS is helpful to be able to identify the components of structural responses to the natural forces as static, quasi-static, or resonant. PMID:22163499

  1. Evaluation of high-precision sensors in structural monitoring.

    PubMed

    Erol, Bihter

    2010-01-01

    One of the most intricate branches of metrology involves the monitoring of displacements and deformations of natural and anthropogenic structures under environmental forces, such as tidal or tectonic phenomena, or ground water level changes. Technological progress has changed the measurement process, and steadily increasing accuracy requirements have led to the continued development of new measuring instruments. The adoption of an appropriate measurement strategy, with proper instruments suited for the characteristics of the observed structure and its environmental conditions, is of high priority in the planning of deformation monitoring processes. This paper describes the use of precise digital inclination sensors in continuous monitoring of structural deformations. The topic is treated from two viewpoints: (i) evaluation of the performance of inclination sensors by comparing them to static and continuous GPS observations in deformation monitoring and (ii) providing a strategy for analyzing the structural deformations. The movements of two case study objects, a tall building and a geodetic monument in Istanbul, were separately monitored using dual-axes micro-radian precision inclination sensors (inclinometers) and GPS. The time series of continuous deformation observations were analyzed using the Least Squares Spectral Analysis Technique (LSSA). Overall, the inclinometers showed good performance for continuous monitoring of structural displacements, even at the sub-millimeter level. Static GPS observations remained insufficient for resolving the deformations to the sub-centimeter level due to the errors that affect GPS signals. With the accuracy advantage of inclination sensors, their use with GPS provides more detailed investigation of deformation phenomena. Using inclinometers and GPS is helpful to be able to identify the components of structural responses to the natural forces as static, quasi-static, or resonant.

  2. Progress Towards a High-Precision Infrared Spectroscopic Survey of the H_3^+ Ion

    NASA Astrophysics Data System (ADS)

    Perry, Adam J.; Hodges, James N.; Markus, Charles R.; Kocheril, G. Stephen; Jenkins, Paul A., II; McCall, Benjamin J.

    2015-06-01

    The trihydrogen cation, H_3^+, represents one of the most important and fundamental molecular systems. Having only two electrons and three nuclei, H_3^+ is the simplest polyatomic system and is a key testing ground for the development of new techniques for calculating potential energy surfaces and predicting molecular spectra. Corrections that go beyond the Born-Oppenheimer approximation, including adiabatic, non-adiabatic, relativistic, and quantum electrodynamic corrections are becoming more feasible to calculate. As a result, experimental measurements performed on the H_3^+ ion serve as important benchmarks which are used to test the predictive power of new computational methods. By measuring many infrared transitions with precision at the sub-MHz level it is possible to construct a list of the most highly precise experimental rovibrational energy levels for this molecule. Until recently, only a select handful of infrared transitions of this molecule have been measured with high precision (˜ 1 MHz). Using the technique of Noise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy, we are aiming to produce the largest high-precision spectroscopic dataset for this molecule to date. Presented here are the current results from our survey along with a discussion of the combination differences analysis used to extract the experimentally determined rovibrational energy levels. O. Polyansky, et al., Phil. Trans. R. Soc. A (2012), 370, 5014. M. Pavanello, et al., J. Chem. Phys. (2012), 136, 184303. L. Diniz, et al., Phys. Rev. A (2013), 88, 032506. L. Lodi, et al., Phys. Rev. A (2014), 89, 032505. J. Hodges, et al., J. Chem. Phys (2013), 139, 164201.

  3. A simple high-precision Jacob's staff design for the high-resolution stratigrapher

    USGS Publications Warehouse

    Elder, W.P.

    1989-01-01

    The new generation of high-resolution stratigraphic research depends upon detailed bed-by-bed analysis to enhance regional correlation potential. The standard Jacob's staff is not an efficient and precise tool for measuring thin-bedded strata. The high-precision Jacob's staff design presented and illustrated in this paper meets the qualifications required of such an instrument. The prototype of this simple design consists of a sliding bracket that holds a Brunton-type compass at right angles to a ruled-off staff. This instrument provides rapid and accurate measurement of both thick- or thin-bedded sequences, thus decreasing field time and increasing stratigraphic precision. -Author

  4. High-precision x-ray spectroscopy in few-electron ions

    NASA Astrophysics Data System (ADS)

    LeBigot, E. O.; Boucard, S.; Covita, D. S.; Gotta, D.; Gruber, A.; Hirtl, A.; Fuhrmann, H.; Indelicato, P.; dos Santos, J. M. F.; Schlesser, S.; Simons, L. M.; Stingelin, L.; Trassinelli, M.; Veloso, J. F. C. A.; Wasser, A.; Zmeskal, J.

    2009-05-01

    The experimental and spectrum analysis procedures that led to about 15 new, high-precision, relative x-ray line energy measurements are presented. The measured lines may be used as x-ray reference lines in the 2.4-3.1 keV range. Applications also include tests of the atomic theory, and in particular of quantum electrodynamics and of relativistic many-body theory calculations. The lines originate from 2- to 4-electron ions of sulfur (Z=16), chlorine (Z=17) and argon (Z=18). The precision reached for their energy ranges from a few parts per million (ppm) to about 50 ppm. This places the new measurements among the most precise performed in mid-Z highly charged ions (Z is the nuclear charge number). The elements of the experimental setup are described: the ion source (an electron cyclotron resonance ion trap), the spectrometer (a single, spherically bent crystal spectrometer), as well as the spectrum acquisition camera (low-noise, high-efficiency CCD). The spectrum analysis procedure, which is based on a full simulation of the spectrometer response function, is also presented.

  5. High-precision heliostat for long-path light tracking

    NASA Astrophysics Data System (ADS)

    Hawat, Tom; Stephen, Thomas M.; DeMaziere, Martine M.; Neefs, Eddy

    2003-08-01

    A heliostat has been designed and built for use in optical remote sensing of the atmosphere. The heliostat uses two flat mirrors to track the sun and direct the sunlight to optical instruments. A stepper motor driven horizontal turntable is used to track the sun in azimuth and support an elevation assembly and a mechanical tower. The stepper motor driven elevation assembly drives an acquisition mirror that tracks the sun in elevation. This mirror directs the solar beam to a secondary mirror fixed on the mechanical tower. The secondary mirror then directs the solar beam along the axis of the tracker for use in measurements. A sensitive, high resolution CCD camera, receives a small part of the solar beam to analyze for fine servo-control. Ground based tests have demonstrated this instrument"s tracking capability for the sun, the moon, stars and for long pathlength sources. Presently, this system is coupled with a high-resolution Brucker 120M spectrometer used to obtain solar absorption spectra. The heliostat directs the solar radiation along the spectrometer optical axis. The pointing precision was measured to be better than 0.5 arcsec. A description of the heliostat is presented, as well as the results of ground tests.

  6. A high-precision synchronization circuit for clock distribution

    NASA Astrophysics Data System (ADS)

    Chong, Lu; Hongzhou, Tan; Zhikui, Duan; Yi, Ding

    2015-10-01

    In this paper, a novel structure of a high-precision synchronization circuit, HPSC, using interleaved delay units and a dynamic compensation circuit is proposed. HPSCs are designed for synchronization of clock distribution networks in large-scale integrated circuits, where high-quality clocks are required. The application of a hybrid structure of a coarse delay line and dynamic compensation circuit performs roughly the alignment of the clock signal in two clock cycles, and finishes the fine tuning in the next three clock cycles with the phase error suppressed under 3.8 ps. The proposed circuit is implemented and fabricated using a SMIC 0.13 μm 1P6M process with a supply voltage at 1.2 V. The allowed operation frequency ranges from 200 to 800 MHz, and the duty cycle ranges between [20%, 80%]. The active area of the core circuits is 245 × 134 μm2, and the power consumption is 1.64 mW at 500 MHz.

  7. High precision Wind measurements in the upper Venus atmosphere

    NASA Astrophysics Data System (ADS)

    Schmuelling, F.; Goldstein, J.; Kostiuk, T.; Hewagama, T.; Zipoy, D.

    2000-10-01

    We will present high accuracy measurements of line-of-sight wind velocities in the upper Venus atmosphere and models of the implied global circulation. The measurements were performed using the NASA/GSFC Infrared Heterodyne Spectrometer at the NASA IRTF. Thermospheric altitudes between 100 and 120 km were probed using 12C16O2 solar-pumped, non-thermal emission. The observed signal-to-noise allowed determination of line center frequencies to a precision of 0.1 MHz (1 m/s at 10 μ m). Absolute frequency calibration was possible to better than 0.1 MHz due to the extremely high frequency stability of the Lamb-dip stabilized heterodyne system. The quality of the data together with the instrument stability allowed measurement of line-of-sight wind velocities across the illuminated crescent to 1 m/s. Data were acquired just before and after inferior conjunction in 1990 and 1991. In combination, these two data sets allowed modeling of the global wind field. Modeled horizontal wind velocities will be presented for a sub-solar to anti-solar flow and a zonal retrograde super-rotation.

  8. Silicon avalanche pixel sensor for high precision tracking

    NASA Astrophysics Data System (ADS)

    D'Ascenzo, N.; Marrocchesi, P. S.; Moon, C. S.; Morsani, F.; Ratti, L.; Saveliev, V.; Savoy Navarro, A.; Xie, Q.

    2014-03-01

    The development of an innovative position sensitive pixelated sensor to detect and measure with high precision the coordinates of the ionizing particles is proposed. The silicon avalanche pixel sensors (APiX) is based on the vertical integration of avalanche pixels connected in pairs and operated in coincidence in fully digital mode and with the processing electronics embedded on the chip. The APiX sensor addresses the need to minimize the material budget and related multiple scattering effects in tracking systems requiring a high spatial resolution in the presence of the large track occupancy. The expected operation of the new sensor features: low noise, low power consumption and suitable radiation tolerance. The APiX device provides on-chip digital information on the position of the coordinate of the impinging charged particle and can be seen as the building block of a modular system of pixelated arrays, implementing a sparsified readout. The technological challenges are the 3D integration of the device under CMOS processes and integration of processing electronics.

  9. A proposed experimental method for interpreting Doppler effect measurements and determining their precision

    NASA Technical Reports Server (NTRS)

    Klann, P. G.

    1973-01-01

    The principal problem in the measurement of the Doppler reactivity effect is separating it from the thermal reactivity effects of the expansion of the heated sample. It is shown in this proposal that the thermal effects of sample expansion can be experimentally determined by making additional measurements with porous samples having the same mass and/or volume as the primary sample. By combining these results with independent measurements of the linear temperature coefficient and the computed temperature dependence of the Doppler coefficient the magnitude of the Doppler coefficient may be extracted from the data. These addiational measurements are also useful to experimentally determine the precision of the reactivity oscillator technique used to measure the reactivity effects of the heated sample.

  10. Precision cosmology with time delay lenses: High resolution imaging requirements

    SciTech Connect

    Meng, Xiao -Lei; Treu, Tommaso; Agnello, Adriano; Auger, Matthew W.; Liao, Kai; Marshall, Philip J.

    2015-09-28

    Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host galaxies of lensed quasars, which appear as ``Einstein Rings'' in high resolution images. The distortion of these arcs and counter-arcs, as measured over a large number of pixels, provides tight constraints on the difference between the gravitational potential between the quasar image positions, and thus on cosmology in combination with the measured time delay. We carry out a systematic exploration of the high resolution imaging required to exploit the thousands of lensed quasars that will be discovered by current and upcoming surveys with the next decade. Specifically, we simulate realistic lens systems as imaged by the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and ground based adaptive optics images taken with Keck or the Thirty Meter Telescope (TMT). We compare the performance of these pointed observations with that of images taken by the Euclid (VIS), Wide-Field Infrared Survey Telescope (WFIRST) and Large Synoptic Survey Telescope (LSST) surveys. We use as our metric the precision with which the slope γ' of the total mass density profile ρtot∝ r–γ' for the main deflector can be measured. Ideally, we require that the statistical error on γ' be less than 0.02, such that it is subdominant to other sources of random and systematic uncertainties. We find that survey data will likely have sufficient depth and resolution to meet the target only for the brighter gravitational lens systems, comparable to those discovered by the SDSS survey. For fainter systems, that will be discovered by current and future surveys, targeted follow-up will be required. Furthermore, the exposure time required with upcoming facilitites such as JWST, the Keck Next Generation Adaptive Optics System, and TMT, will

  11. Precision cosmology with time delay lenses: high resolution imaging requirements

    SciTech Connect

    Meng, Xiao-Lei; Liao, Kai; Treu, Tommaso; Agnello, Adriano; Auger, Matthew W.; Marshall, Philip J. E-mail: tt@astro.ucla.edu E-mail: mauger@ast.cam.ac.uk E-mail: dr.phil.marshall@gmail.com

    2015-09-01

    Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host galaxies of lensed quasars, which appear as ''Einstein Rings'' in high resolution images. The distortion of these arcs and counter-arcs, as measured over a large number of pixels, provides tight constraints on the difference between the gravitational potential between the quasar image positions, and thus on cosmology in combination with the measured time delay. We carry out a systematic exploration of the high resolution imaging required to exploit the thousands of lensed quasars that will be discovered by current and upcoming surveys with the next decade. Specifically, we simulate realistic lens systems as imaged by the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and ground based adaptive optics images taken with Keck or the Thirty Meter Telescope (TMT). We compare the performance of these pointed observations with that of images taken by the Euclid (VIS), Wide-Field Infrared Survey Telescope (WFIRST) and Large Synoptic Survey Telescope (LSST) surveys. We use as our metric the precision with which the slope γ' of the total mass density profile ρ{sub tot}∝ r{sup −γ'} for the main deflector can be measured. Ideally, we require that the statistical error on γ' be less than 0.02, such that it is subdominant to other sources of random and systematic uncertainties. We find that survey data will likely have sufficient depth and resolution to meet the target only for the brighter gravitational lens systems, comparable to those discovered by the SDSS survey. For fainter systems, that will be discovered by current and future surveys, targeted follow-up will be required. However, the exposure time required with upcoming facilitites such as JWST, the Keck Next Generation Adaptive Optics System, and TMT, will

  12. Experimental study of the quantitative precision for valve-based comprehensive two-dimensional gas chromatography.

    PubMed

    Siegler, W Christopher; Fitz, Brian D; Hoggard, Jamin C; Synovec, Robert E

    2011-07-01

    For complex sample analysis, there is a need for multidimensional chromatographic instrumentation to be able to separate more compounds, often in shorter time frames. This has led to the development of comprehensive two-dimensional chromatographic instrumentation, such as comprehensive two-dimensional gas chromatography (GC × GC). Lately, much of the focus in this field has been on decreasing peak widths and, therefore, increasing peak capacity and peak capacity production. All of these advancements make it possible to analyze more compounds in a shorter amount of time, but the data still need to remain quantitative to address the needs of most applications. In this report, the relationship among the modulation ratio (M(R)), peak sampling phase (φ), retention time variation (Δt(R)), and how these parameters relate to quantitative analysis precision via the relative standard deviation (RSD) was studied experimentally using a valve-based GC × GC instrument. A wide range of the number of modulations across the first dimension peak width, that is, a M(R) range from ~1 to 10, was examined through maintaining an average first dimension peak width at the base, (1)w(b) of ~3 s and varying the second dimension separation run time from 300 to 2900 ms. An average RSD of 2.1% was experimentally observed at an average M(R) of 2, with a corresponding peak capacity production of ~1200 peaks/min possible. Below this M(R) the RSD quickly increased. In a long-term study of the quantitative precision at a M(R) of 2.5, using 126 replicate injections of a test mixture spanning ~35 h, the RSD averaged 3.0%. The findings have significant implications for optimizing peak capacity production by allowing the use of the longest second dimension run time, while maintaining quantitative precision. PMID:21627311

  13. Two-dimensional, high flow, precisely controlled monodisperse drop source

    NASA Astrophysics Data System (ADS)

    Dressler, John L.

    1993-03-01

    A versatile acoustically-driven fluid atomizer was designed and operated that creates precise monodisperse sprays by Rayleigh breakup or polydisperse sprays by the acoustic driving of amplitude dependent instabilities. The atomizer forms a cylindrical, conical, or flat (sheet) liquid jet by means of a photofabricated nozzle. The spray pattern and spray volume are altered by changing the nozzle. A piezoelectric driver, constructed to efficiently couple energy to the liquid, modulates the fluid velocity. When operated at low power, the drop generator can produce arrays of monodisperse drops as small as 15 microns in diameter. Operating the piezoelectric driver at high power produces perturbations with sufficient energy to break the liquid jets into drops, with a net increase in surface energy. The resulting drop sizes are influenced by the frequency and amplitude of the driving signal and nozzle size. The spatial distribution of the spray is controlled by the spacing and geometry of the holes in the nozzle plate, the amplitude of the acoustic signal, and the swirl in the fluid manifold. This device is more robust than the typical acoustic drop generator because small drops can be made from large holes, reducing the plugging problem. No air flow is used.

  14. High precision relocation of earthquakes at Iliamna Volcano, Alaska

    USGS Publications Warehouse

    Statz-Boyer, P.; Thurber, C.; Pesicek, J.; Prejean, S.

    2009-01-01

    In August 1996, a period of elevated seismicity commenced beneath Iliamna Volcano, Alaska. This activity lasted until early 1997, consisted of over 3000 earthquakes, and was accompanied by elevated emissions of volcanic gases. No eruption occurred and seismicity returned to background levels where it has remained since. We use waveform alignment with bispectrum-verified cross-correlation and double-difference methods to relocate over 2000 earthquakes from 1996 to 2005 with high precision (~ 100??m). The results of this analysis greatly clarify the distribution of seismic activity, revealing distinct features previously hidden by location scatter. A set of linear earthquake clusters diverges upward and southward from the main group of earthquakes. The events in these linear clusters show a clear southward migration with time. We suggest that these earthquakes represent either a response to degassing of the magma body, circulation of fluids due to exsolution from magma or heating of ground water, or possibly the intrusion of new dikes beneath Iliamna's southern flank. In addition, we speculate that the deeper, somewhat diffuse cluster of seismicity near and south of Iliamna's summit indicates the presence of an underlying magma body between about 2 and 4??km depth below sea level, based on similar features found previously at several other Alaskan volcanoes. ?? 2009 Elsevier B.V.

  15. 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.

  16. Report on APMP supplementary comparison: high precision roundness measurement

    NASA Astrophysics Data System (ADS)

    Buajarern, J.; Naoi, K.; Baker, A.; Zi, X.; Tsai, C.-L.; Eom, T. B.; Leng, T. S.; Kruger, O.

    2016-01-01

    A regional supplementary comparison, APMP.L-S4, was held in 2012 to demonstrate the equivalence of routine calibration services offered by NMIs to clients. Participants in this APMP.L-S4 comparison agreed to apply multi-step method for spidle error separation in order to yield the high precision roundness measurement. Eight laboratories from NMIs participated in this supplementary comparison; NIMT, NMIJ, NMIA, NIM, CMS/ITRI, KRISS, NMC/A*STAR and NMISA. This report describes the measurement results of 2 glass hemispheres and 2 softgauges. The calibrations of this comparison were carried out by participants during the period from March 2012 to May 2013. The results show that there is a degree of equivalence within 0.8 for all measurands. Hence, there is a close agreement between the measurements. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  17. High-precision impedance spectroscopy: a strategy demonstrated on PZT.

    PubMed

    Boukamp, Bernard A; Blank, Dave H A

    2011-12-01

    Electrochemical impedance spectroscopy (EIS) has been recognized as a very powerful tool for studying charge and mass transport and transfer in a wide variety of electrically or electrochemically active systems. Sophisticated modeling programs make it possible to extract parameters from the impedance data, thus contributing to a better understanding of the system or material properties. For an accurate analysis, a correct modeling function is needed; this is often in the form of an equivalent circuit. It is not always possible to define the modeling function from visual inspection of the impedance dispersion. Small contributions to the overall dispersion can be masked, and hence overlooked. In this publication, a strategy is presented for high-precision impedance data analysis. A Kramers-Kronig test is used for the essential data validation. An iterative process of partial analysis and subtraction assists in deconvoluting the impedance spectrum, yielding both a vi- able model function and a set of necessary starting values for the full complex nonlinear least squares (CNLS) modeling. The advantage and possibilities of this strategy are demonstrated with an analysis of the ionic and electronic conductivity of lead zirconate titanate (PZT) as functions of temperature and oxygen partial pressure. PMID:23443688

  18. French Meteor Network for High Precision Orbits of Meteoroids

    NASA Technical Reports Server (NTRS)

    Atreya, P.; Vaubaillon, J.; Colas, F.; Bouley, S.; Gaillard, B.; Sauli, I.; Kwon, M. K.

    2011-01-01

    There is a lack of precise meteoroids orbit from video observations as most of the meteor stations use off-the-shelf CCD cameras. Few meteoroids orbit with precise semi-major axis are available using film photographic method. Precise orbits are necessary to compute the dust flux in the Earth s vicinity, and to estimate the ejection time of the meteoroids accurately by comparing them with the theoretical evolution model. We investigate the use of large CCD sensors to observe multi-station meteors and to compute precise orbit of these meteoroids. An ideal spatial and temporal resolution to get an accuracy to those similar of photographic plates are discussed. Various problems faced due to the use of large CCD, such as increasing the spatial and the temporal resolution at the same time and computational problems in finding the meteor position are illustrated.

  19. 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

  20. 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.

  1. Ultra High Precision Laser Monitor for Oxygen Eddy Flux Measurements

    NASA Astrophysics Data System (ADS)

    Zahniser, M. S.; Nelson, D. D.; Roscioli, J. R.; Herndon, S. C.; McManus, J. B.; Jervis, D.

    2015-12-01

    Atmospheric oxygen provides one of the most powerful tracers to study the carbon cycle through its close interaction with carbon dioxide. Keeling and co-workers demonstrated this at the global scale by using small variations in atmospheric oxygen content to disentangle oceanic and terrestrial carbon sinks. It would be very exciting to apply similar ideas at the ecosystem level to improve our understanding of biosphere-atmosphere exchange and our ability to predict the response of the biosphere and atmosphere to climate change. The eddy covariance technique is perhaps the most effective approach available to quantify the exchange of gases between these spheres. Therefore, eddy covariance flux measurements of oxygen would be extremely valuable. However, this requires a fast response (0.1 seconds), high relative precision (0.001% or 10 per meg) oxygen sensor. We report recent progress in developing such a sensor using a high resolution visible laser to probe the oxygen A-band electronic transition. This sensor will enable oxygen flux measurements using eddy covariance. In addition, we will incorporate a second laser in this instrument to simultaneously determine the fluxes of oxygen, carbon dioxide and water vapor within the same sampling cell. This will provide a direct, real time measurement of the ratio of the flux of oxygen to that of carbon dioxide. This ratio is expected to vary on short time scales and small spatial scales due to the differing stoichiometry of processes producing and consuming carbon dioxide. Thus measuring the variations in the ratio of oxygen and carbon dioxide fluxes will provide mechanistic information to improve our understanding of the crucial exchange of carbon between the atmosphere and biosphere.

  2. Experimental Hypersonic Aerodynamic Characteristics of the 2001 Mars Surveyor Precision Lander with Flap

    NASA Technical Reports Server (NTRS)

    Horvath, Thomas J.; OConnell, Tod F.; Cheatwood, F. McNeil; Prabhu, Ramadas K.; Alter, Stephen J.

    2002-01-01

    Aerodynamic wind-tunnel screening tests were conducted on a 0.029 scale model of a proposed Mars Surveyor 2001 Precision Lander (70 deg half angle spherically blunted cone with a conical afterbody). The primary experimental objective was to determine the effectiveness of a single flap to trim the vehicle at incidence during a lifting hypersonic planetary entry. The laminar force and moment data, presented in the form of coefficients, and shock patterns from schlieren photography were obtained in the NASA Langley Aerothermodynamic Laboratory for post-normal shock Reynolds numbers (based on forebody diameter) ranging from 2,637 to 92,350, angles of attack ranging from 0 tip to 23 degrees at 0 and 2 degree sideslip, and normal-shock density ratios of 5 and 12. Based upon the proposed entry trajectory of the 2001 Lander, the blunt body heavy gas tests in CF, simulate a Mach number of approximately 12 based upon a normal shock density ratio of 12 in flight at Mars. The results from this experimental study suggest that when traditional means of providing aerodynamic trim for this class of planetary entry vehicle are not possible (e.g. offset c.g.), a single flap can provide similar aerodynamic performance. An assessment of blunt body aerodynamic effects attributed to a real gas were obtained by synergistic testing in Mach 6 ideal-air at a comparable Reynolds number. From an aerodynamic perspective, an appropriately sized flap was found to provide sufficient trim capability at the desired L/D for precision landing. Inviscid hypersonic flow computations using an unstructured grid were made to provide a quick assessment of the Lander aerodynamics. Navier-Stokes computational predictions were found to be in very good agreement with experimental measurement.

  3. Precision optical slit for high heat load or ultra high vacuum

    DOEpatents

    Andresen, Nord C.; DiGennaro, Richard S.; Swain, Thomas L.

    1995-01-01

    This invention relates generally to slits used in optics that must be precisely aligned and adjusted. The optical slits of the present invention are useful in x-ray optics, x-ray beam lines, optical systems in which the entrance slit is critical for high wavelength resolution. The invention is particularly useful in ultra high vacuum systems where lubricants are difficult to use and designs which avoid the movement of metal parts against one another are important, such as monochrometers for high wavelength resolution with ultra high vacuum systems. The invention further relates to optical systems in which temperature characteristics of the slit materials is important. The present invention yet additionally relates to precision slits wherein the opposing edges of the slit must be precisely moved relative to a center line between the edges with each edge retaining its parallel orientation with respect to the other edge and/or the center line.

  4. Precision optical slit for high heat load or ultra high vacuum

    DOEpatents

    Andresen, N.C.; DiGennaro, R.S.; Swain, T.L.

    1995-01-24

    This invention relates generally to slits used in optics that must be precisely aligned and adjusted. The optical slits of the present invention are useful in x-ray optics, x-ray beam lines, optical systems in which the entrance slit is critical for high wavelength resolution. The invention is particularly useful in ultra high vacuum systems where lubricants are difficult to use and designs which avoid the movement of metal parts against one another are important, such as monochromators for high wavelength resolution with ultra high vacuum systems. The invention further relates to optical systems in which temperature characteristics of the slit materials is important. The present invention yet additionally relates to precision slits wherein the opposing edges of the slit must be precisely moved relative to a center line between the edges with each edge retaining its parallel orientation with respect to the other edge and/or the center line. 21 figures.

  5. High Precision Prediction of Functional Sites in Protein Structures

    PubMed Central

    Buturovic, Ljubomir; Wong, Mike; Tang, Grace W.; Altman, Russ B.; Petkovic, Dragutin

    2014-01-01

    We address the problem of assigning biological function to solved protein structures. Computational tools play a critical role in identifying potential active sites and informing screening decisions for further lab analysis. A critical parameter in the practical application of computational methods is the precision, or positive predictive value. Precision measures the level of confidence the user should have in a particular computed functional assignment. Low precision annotations lead to futile laboratory investigations and waste scarce research resources. In this paper we describe an advanced version of the protein function annotation system FEATURE, which achieved 99% precision and average recall of 95% across 20 representative functional sites. The system uses a Support Vector Machine classifier operating on the microenvironment of physicochemical features around an amino acid. We also compared performance of our method with state-of-the-art sequence-level annotator Pfam in terms of precision, recall and localization. To our knowledge, no other functional site annotator has been rigorously evaluated against these key criteria. The software and predictive models are incorporated into the WebFEATURE service at http://feature.stanford.edu/wf4.0-beta. PMID:24632601

  6. Highly precise digital image stabilization scheme for a hybrid stabilizing system

    NASA Astrophysics Data System (ADS)

    Kim, Jin-Hyung; Byun, Keun-Yung; Ko, Sung-Jea

    2010-07-01

    We propose a highly precise digital image stabilization (DIS) scheme for a hybrid stabilizing system. The stabilizing system adopts a hybrid method of using both optical image stabilization (OIS) and DIS. In the stabilizing system, OIS prestabilizes the original unstable image using gyro-sensors, and the resultant image obtained from OIS is post-stabilized using DIS to remove the residual jitters less than one pixel. The proposed DIS, which is newly designed using control-grid interpolation, can remove not only translational jitters but also rotational ones simultaneously. Experimental results show that the proposed hybrid image stabilizer achieves considerable performance improvement against conventional stabilization techniques.

  7. High-precision measurement of chlorine stable isotope ratios

    USGS Publications Warehouse

    Long, A.; Eastoe, C.J.; Kaufmann, R.S.; Martin, J.G.; Wirt, L.; Finley, J.B.

    1993-01-01

    We present an analysis procedure that allows stable isotopes of chlorine to be analyzed with precision sufficient for geological and hydrological studies. The total analytical precision is ?????0.09%., and the present known range of chloride in the surface and near-surface environment is 3.5???. As Cl- is essentially nonreactive in natural aquatic environments, it is a conservative tracer and its ??37Cl is also conservative. Thus, the ??37Cl parameter is valuable for quantitative evaluation of mixing of different sources of chloride in brines and aquifers. ?? 1993.

  8. High precision, high sensitivity distributed displacement and temperature measurements using OFDR-based phase tracking

    NASA Astrophysics Data System (ADS)

    Gifford, Dawn K.; Froggatt, Mark E.; Kreger, Stephen T.

    2011-05-01

    Optical Frequency Domain Reflectometry is used to measure distributed displacement and temperature change with very high sensitivity and precision by measuring the phase change of an optical fiber sensor as a function of distance with high spatial resolution and accuracy. A fiber containing semi-continuous Bragg gratings was used as the sensor. The effective length change, or displacement, in the fiber caused by small temperature changes was measured as a function of distance with a precision of 2.4 nm and a spatial resolution of 1.5 mm. The temperature changes calculated from this displacement were measured with precision of 0.001 C with an effective sensor gauge length of 12 cm. These results demonstrate that the method employed of continuously tracking the phase change along the length of the fiber sensor enables high resolution distributed measurements that can be used to detect very small displacements, temperature changes, or strains.

  9. Precision Teaching in the High School Classroom: A Commentary

    ERIC Educational Resources Information Center

    Brophy, Jere E.

    1978-01-01

    In a review of Breuning's study of conventional vs. precision teaching (TM 503 458), Brophy praises the research design used. However, the interpretation and reporting of Breuning's data are questioned. The effects of instructional method have been confused with the effects of incentive manipulation. The practicality and ethical justification are…

  10. Development and Validation of High Precision Thermal, Mechanical, and Optical Models for the Space Interferometry Mission

    NASA Technical Reports Server (NTRS)

    Lindensmith, Chris A.; Briggs, H. Clark; Beregovski, Yuri; Feria, V. Alfonso; Goullioud, Renaud; Gursel, Yekta; Hahn, Inseob; Kinsella, Gary; Orzewalla, Matthew; Phillips, Charles

    2006-01-01

    SIM Planetquest (SIM) is a large optical interferometer for making microarcsecond measurements of the positions of stars, and to detect Earth-sized planets around nearby stars. To achieve this precision, SIM requires stability of optical components to tens of picometers per hour. The combination of SIM s large size (9 meter baseline) and the high stability requirement makes it difficult and costly to measure all aspects of system performance on the ground. To reduce risks, costs and to allow for a design with fewer intermediate testing stages, the SIM project is developing an integrated thermal, mechanical and optical modeling process that will allow predictions of the system performance to be made at the required high precision. This modeling process uses commercial, off-the-shelf tools and has been validated against experimental results at the precision of the SIM performance requirements. This paper presents the description of the model development, some of the models, and their validation in the Thermo-Opto-Mechanical (TOM3) testbed which includes full scale brassboard optical components and the metrology to test them at the SIM performance requirement levels.

  11. Preliminary design approach for large high precision segmented reflectors

    NASA Technical Reports Server (NTRS)

    Mikulas, Martin M., Jr.; Collins, Timothy J.; Hedgepeth, John M.

    1990-01-01

    A simplified preliminary design capability for erectable precision segmented reflectors is presented. This design capability permits a rapid assessment of a wide range of reflector parameters as well as new structural concepts and materials. The preliminary design approach was applied to a range of precision reflectors from 10 meters to 100 meters in diameter while considering standard design drivers. The design drivers considered were: weight, fundamental frequency, launch packaging volume, part count, and on-orbit assembly time. For the range of parameters considered, on-orbit assembly time was identified as the major design driver. A family of modular panels is introduced which can significantly reduce the number of reflector parts and the on-orbit assembly time.

  12. Ion source for high-precision mass spectrometry

    DOEpatents

    Todd, Peter J.; McKown, Henry S.; Smith, David H.

    1984-01-01

    The invention is directed to a method for increasing the precision of positive-ion relative abundance measurements conducted in a sector mass spectrometer having an ion source for directing a beam of positive ions onto a collimating slit. The method comprises incorporating in the source an electrostatic lens assembly for providing a positive-ion beam of circular cross section for collimation by the slit.

  13. Ion source for high-precision mass spectrometry

    DOEpatents

    Todd, P.J.; McKown, H.S.; Smith, D.H.

    1982-04-26

    The invention is directed to a method for increasing the precision of positive-ion relative abundance measurements conducted in a sector mass spectrometer having an ion source for directing a beam of positive ions onto a collimating slit. The method comprises incorporating in the source an electrostatic lens assembly for providing a positive-ion beam of circular cross section for collimation by the slit. 2 figures, 3 tables.

  14. Gauges for Highly Precise Metrology of a Compound Mirror

    NASA Technical Reports Server (NTRS)

    Gursel, Yekta

    2005-01-01

    Three optical gauges have been developed for guiding the assembly and measuring precisely the reflecting surfaces of a compound mirror that comprises a corner-cube retroreflector glued in a hole on a flat mirror. In the specific application for which the gauges were developed, the compound mirror is part of a siderostat in a stellar interferometer. The flat-mirror portion of the compound mirror is the siderostat mirror; the retroreflector portion of the compound mirror is to be used, during operation of the interferometer, to monitor the location of the siderostat mirror surface relative to other optical surfaces of the interferometer. Nominally, the optical corner of the retroreflector should lie precisely on the siderostat mirror surface, but this precision cannot be achieved in fabrication: in practice, there remains some distance between the optical corner and the siderostat mirror surface. For proper operation of the interferometer, it is required to make this distance as small as possible and to know this distance within 1 nm. The three gauges make it possible to satisfy these requirements.

  15. Vibratory response modeling and verification of a high precision optical positioning system.

    SciTech Connect

    Barraza, J.; Kuzay, T.; Royston, T. J.; Shu, D.

    1999-06-18

    A generic vibratory-response modeling program has been developed as a tool for designing high-precision optical positioning systems. Based on multibody dynamics theory, the system is modeled as rigid-body structures connected by linear elastic elements, such as complex actuators and bearings. The full dynamic properties of each element are determined experimentally or theoretically, then integrated into the program as inertial and stiffness matrices. Utilizing this program, the theoretical and experimental verification of the vibratory behavior of a double-multilayer monochromator support and positioning system is presented. Results of parametric design studies that investigate the influence of support floor dynamics and highlight important design issues are also presented. Overall, good matches between theory and experiment demonstrate the effectiveness of the program as a dynamic modeling tool.

  16. Animal Experimentation in High Schools

    ERIC Educational Resources Information Center

    Ansevin, Kystyna D.

    1970-01-01

    Recommends that teacher and student be provided with the broadest possible spectrum of meaningful and feasible experiments in which the comfort of the experimental animal is protected by the design of the experiment. (BR)

  17. Computational Calorimetry: High-Precision Calculation of Host–Guest Binding Thermodynamics

    PubMed Central

    2015-01-01

    We present a strategy for carrying out high-precision calculations of binding free energy and binding enthalpy values from molecular dynamics simulations with explicit solvent. The approach is used to calculate the thermodynamic profiles for binding of nine small molecule guests to either the cucurbit[7]uril (CB7) or β-cyclodextrin (βCD) host. For these systems, calculations using commodity hardware can yield binding free energy and binding enthalpy values with a precision of ∼0.5 kcal/mol (95% CI) in a matter of days. Crucially, the self-consistency of the approach is established by calculating the binding enthalpy directly, via end point potential energy calculations, and indirectly, via the temperature dependence of the binding free energy, i.e., by the van’t Hoff equation. Excellent agreement between the direct and van’t Hoff methods is demonstrated for both host–guest systems and an ion-pair model system for which particularly well-converged results are attainable. Additionally, we find that hydrogen mass repartitioning allows marked acceleration of the calculations with no discernible cost in precision or accuracy. Finally, we provide guidance for accurately assessing numerical uncertainty of the results in settings where complex correlations in the time series can pose challenges to statistical analysis. The routine nature and high precision of these binding calculations opens the possibility of including measured binding thermodynamics as target data in force field optimization so that simulations may be used to reliably interpret experimental data and guide molecular design. PMID:26523125

  18. Computational Calorimetry: High-Precision Calculation of Host-Guest Binding Thermodynamics.

    PubMed

    Henriksen, Niel M; Fenley, Andrew T; Gilson, Michael K

    2015-09-01

    We present a strategy for carrying out high-precision calculations of binding free energy and binding enthalpy values from molecular dynamics simulations with explicit solvent. The approach is used to calculate the thermodynamic profiles for binding of nine small molecule guests to either the cucurbit[7]uril (CB7) or β-cyclodextrin (βCD) host. For these systems, calculations using commodity hardware can yield binding free energy and binding enthalpy values with a precision of ∼0.5 kcal/mol (95% CI) in a matter of days. Crucially, the self-consistency of the approach is established by calculating the binding enthalpy directly, via end point potential energy calculations, and indirectly, via the temperature dependence of the binding free energy, i.e., by the van't Hoff equation. Excellent agreement between the direct and van't Hoff methods is demonstrated for both host-guest systems and an ion-pair model system for which particularly well-converged results are attainable. Additionally, we find that hydrogen mass repartitioning allows marked acceleration of the calculations with no discernible cost in precision or accuracy. Finally, we provide guidance for accurately assessing numerical uncertainty of the results in settings where complex correlations in the time series can pose challenges to statistical analysis. The routine nature and high precision of these binding calculations opens the possibility of including measured binding thermodynamics as target data in force field optimization so that simulations may be used to reliably interpret experimental data and guide molecular design.

  19. A new approach to high precision phase measurement interferometry

    NASA Astrophysics Data System (ADS)

    Balasubramanian, N.; Debell, G. W.

    1980-01-01

    A description is presented of a phase measuring interferometer system which represents a unique approach to the extraction and analysis of wavefront data from the interferometer output. In contrast to fringe pattern analysis systems, the digitally based instrument described is a direct phase measuring interferometer system which is capable of providing a graphical representation of both the sign and magnitude of the phase distribution across the test wavefront. Attention is given to basic theory, the instrument measurement head, the 8080-based computer used as a processor, system performance specifications, measurement precision and accuracy, and measurement capabilities.

  20. High-precision temperature control and stabilization using a cryocooler.

    PubMed

    Hasegawa, Yasuhiro; Nakamura, Daiki; Murata, Masayuki; Yamamoto, Hiroya; Komine, Takashi

    2010-09-01

    We describe a method for precisely controlling temperature using a Gifford-McMahon (GM) cryocooler that involves inserting fiber-reinforced-plastic dampers into a conventional cryosystem. Temperature fluctuations in a GM cryocooler without a large heat bath or a stainless-steel damper at 4.2 K are typically of the order of 200 mK. It is particularly difficult to control the temperature of a GM cryocooler at low temperatures. The fiber-reinforced-plastic dampers enabled us to dramatically reduce temperature fluctuations at low temperatures. A standard deviation of the temperature fluctuations of 0.21 mK could be achieved when the temperature was controlled at 4.200 0 K using a feedback temperature control system with two heaters. Adding the dampers increased the minimum achievable temperature from 3.2 to 3.3 K. Precise temperature control between 4.200 0 and 300.000 K was attained using the GM cryocooler, and the standard deviation of the temperature fluctuations was less than 1.2 mK even at 300 K. This technique makes it possible to control and stabilize the temperature using a GM cryocooler.

  1. High-precision analysis of SF6 at ambient level

    NASA Astrophysics Data System (ADS)

    Lim, J. S.; Moon, D. M.; Kim, J. S.; Yun, W.-T.; Lee, J.

    2013-09-01

    This work reports on the development of a technique for the precise analysis of ambient SF6. This technique, which involves a gas chromatograph/electron capture detector (GC-ECD) coupled with an Activated Alumina-F1 (AA-F1) column, performed well in the measurements, particularly in terms of accuracy, which complies with the World Meteorological Organization (WMO)-recommended compatibility of 0.02 ppt. Compared to the Porapak Q technique, we observed a sharper peak shape for the SF6 stream, which substantiates the improvement in the analytical precision. The traceability to the WMO scale was tested by calibrating the GC-ECD/AA-F1 analyser using five SF6 standards provided by the WMO/Global Atmosphere Watch (GAW) Central Calibration Laboratory (CCL) for SF6 (NOAA, United States of America). After calibration by various methods, the GC-ECD/AA-F1 accurately estimated the mole fraction of SF6 in the working standard prepared by the World Calibration Centre for SF6 operated by the Korea Meteorological Administration (KMA)/Korea Research Institute of Standards and Science (KRISS). Among the calibration methods, the two-point calibration method emerged to be the most economical procedure in terms of the data quality and measurement time. It was found that the KRISS scale of SF6/N2 was biased by 0.13 ppt when compared to the WMO scale of SF6/air; this bias is probably due to a different matrix.

  2. Precision compression molding of glass microlenses and microlens arrays--an experimental study.

    PubMed

    Firestone, G C; Yi, A Y

    2005-10-10

    An innovative manufacturing process utilizing high-temperature compression molding to fabricate aspherical microlenses by using optical glasses, such as BK7, K-PG325, and soda-lime glass, is investigated. In a departure from conventional approaches, a unique hollow contactless mold design is adopted. Polished glass substrates and the mold assembly are heated above the glass transition temperature first, followed by initial forming, then annealing. The forming rate is controlled in real time to ensure mold position accuracy. Mold materials used include tungsten carbides, 316 stainless steel, 715 copper nickel, and aluminum alloys. The geometric control of the microlenses or microlens arrays can be precisely controlled by the forming temperature, forming speed, mold design, and annealing time.

  3. Proceedings, High-Precision $\\alpha_s$ Measurements from LHC to FCC-ee

    SciTech Connect

    d'Enterria, David; Skands, Peter Z.

    2015-01-01

    This document provides a writeup of all contributions to the workshop on "High precision measurements of $\\alpha_s$: From LHC to FCC-ee" held at CERN, Oct. 12--13, 2015. The workshop explored in depth the latest developments on the determination of the QCD coupling $\\alpha_s$ from 15 methods where high precision measurements are (or will be) available. Those include low-energy observables: (i) lattice QCD, (ii) pion decay factor, (iii) quarkonia and (iv) $\\tau$ decays, (v) soft parton-to-hadron fragmentation functions, as well as high-energy observables: (vi) global fits of parton distribution functions, (vii) hard parton-to-hadron fragmentation functions, (viii) jets in $e^\\pm$p DIS and $\\gamma$-p photoproduction, (ix) photon structure function in $\\gamma$-$\\gamma$, (x) event shapes and (xi) jet cross sections in $e^+e^-$ collisions, (xii) W boson and (xiii) Z boson decays, and (xiv) jets and (xv) top-quark cross sections in proton-(anti)proton collisions. The current status of the theoretical and experimental uncertainties associated to each extraction method, the improvements expected from LHC data in the coming years, and future perspectives achievable in $e^+e^-$ collisions at the Future Circular Collider (FCC-ee) with $\\cal{O}$(1--100 ab$^{-1}$) integrated luminosities yielding 10$^{12}$ Z bosons and jets, and 10$^{8}$ W bosons and $\\tau$ leptons, are thoroughly reviewed. The current uncertainty of the (preliminary) 2015 strong coupling world-average value, $\\alpha_s(m_Z)$ = 0.1177 $\\pm$ 0.0013, is about 1\\%. Some participants believed this may be reduced by a factor of three in the near future by including novel high-precision observables, although this opinion was not universally shared. At the FCC-ee facility, a factor of ten reduction in the $\\alpha_s$ uncertainty should be possible, mostly thanks to the huge Z and W data samples available.

  4. A high precision, compact electromechanical ground rotation sensor.

    PubMed

    Dergachev, V; DeSalvo, R; Asadoor, M; Bhawal, A; Gong, P; Kim, C; Lottarini, A; Minenkov, Y; Murphy, C; O'Toole, A; Peña Arellano, F E; Rodionov, A V; Shaner, M; Sobacchi, E

    2014-05-01

    We present a mechanical rotation sensor consisting of a balance pivoting on a tungsten carbide knife edge. These sensors are important for precision seismic isolation systems, as employed in land-based gravitational wave interferometers and for the new field of rotational seismology. The position sensor used is an air-core linear variable differential transformer with a demonstrated noise floor of 1 × 10⁻¹¹ m/√Hz. We describe the instrument construction and demonstrate low noise operation with a noise floor upper bound of 5.7 × 10⁻⁹ rad/√Hz at 10 mHz and 6.4 × 10⁻¹⁰ rad/√Hz at 0.1 Hz. The performance of the knife edge hinge is compatible with a behaviorur free of noise from dislocation self-organized criticality. PMID:24880388

  5. BAM: A metrology device for a high precision astrometric mission

    NASA Astrophysics Data System (ADS)

    Riva, A.; Gai, M.; Lattanzi, M. G.; Russo, F.; Buzzi, R.

    2014-12-01

    Gaia is ESA next-generation astrometric space mission, that will be launched in December 2013. The main objective of Gaia is to produce an astrometric census of one billion objects down to the 20th magnitude. The level of astrometric precision will be around the 10 microarcseconds. In order to achieve such demanding performances, the complexity of the satellite is huge, and a proper fully automated operation must be adopted. One of the essential parts of the satellite is the BAM instrument, an interferometric device with the task of monitoring the variation of the Basic Angle between the two telescope that compose the payload. In this paper we describe the main features of this sub-instrument and its performances.

  6. Decade-Spanning High-Precision Terahertz Frequency Comb

    NASA Astrophysics Data System (ADS)

    Finneran, Ian A.; Good, Jacob T.; Holland, Daniel B.; Carroll, P. Brandon; Allodi, Marco A.; Blake, Geoffrey A.

    2015-04-01

    The generation and detection of a decade-spanning terahertz (THz) frequency comb is reported using two Ti:sapphire femtosecond laser oscillators and asynchronous optical sampling THz time-domain spectroscopy. The comb extends from 0.15 to 2.4 THz, with a tooth spacing of 80 MHz, a linewidth of 3.7 kHz, and a fractional precision of 1.8 ×10-9 . With time-domain detection of the comb, we measure three transitions of water vapor at 10 mTorr between 1-2 THz with an average Doppler-limited fractional accuracy of 6.1 ×10-8 . Significant improvements in bandwidth, resolution, and sensitivity are possible with existing technologies.

  7. A high precision, compact electromechanical ground rotation sensor

    SciTech Connect

    Dergachev, V.; DeSalvo, R.; Asadoor, M.; Bhawal, A.; Gong, P.; Kim, C.; Lottarini, A.; Minenkov, Y.; Murphy, C.; O'Toole, A.; Peña Arellano, F. E.; and others

    2014-05-15

    We present a mechanical rotation sensor consisting of a balance pivoting on a tungsten carbide knife edge. These sensors are important for precision seismic isolation systems, as employed in land-based gravitational wave interferometers and for the new field of rotational seismology. The position sensor used is an air-core linear variable differential transformer with a demonstrated noise floor of 1 × 10{sup −11}m/√( Hz ). We describe the instrument construction and demonstrate low noise operation with a noise floor upper bound of 5.7 × 10{sup −9} rad /√( Hz ) at 10 mHz and 6.4 × 10{sup −10} rad /√( Hz ) at 0.1 Hz. The performance of the knife edge hinge is compatible with a behaviorur free of noise from dislocation self-organized criticality.

  8. Aerospace Laser Ignition/Ablation Variable High Precision Thruster

    NASA Technical Reports Server (NTRS)

    Campbell, Jonathan W. (Inventor); Edwards, David L. (Inventor); Campbell, Jason J. (Inventor)

    2015-01-01

    A laser ignition/ablation propulsion system that captures the advantages of both liquid and solid propulsion. A reel system is used to move a propellant tape containing a plurality of propellant material targets through an ignition chamber. When a propellant target is in the ignition chamber, a laser beam from a laser positioned above the ignition chamber strikes the propellant target, igniting the propellant material and resulting in a thrust impulse. The propellant tape is advanced, carrying another propellant target into the ignition chamber. The propellant tape and ignition chamber are designed to ensure that each ignition event is isolated from the remaining propellant targets. Thrust and specific impulse may by precisely controlled by varying the synchronized propellant tape/laser speed. The laser ignition/ablation propulsion system may be scaled for use in small and large applications.

  9. High Precision Cosmology with the Cosmic Background Radiation

    NASA Astrophysics Data System (ADS)

    Farhang, Marzieh

    In this thesis we investigate the two cosmic epochs of inflation and recombination, through their imprints on the temperature and polarization anisotropies of the cosmic microwave background radiation. To probe the early universe we develop a map-based maximum-likelihood estimator to measure the amplitude of inflation-induced gravity waves, parametrized by r, from the cosmic microwave background (CMB) polarization maps. Being optimal by construction, the estimator avoids E-B mixing, a possible source of contamination in the tiny B-mode detection, the target of many current and near future CMB experiments. We explore the leakage from the E- to the B-mode of polarization by using this estimator to study the linear response of the B-mode signal at different scales to variations in the E- mode power. Similarly, for various observational cases, we probe the dependence of r measurement on the signal from different scales of E and B polarization. The estimator is used to make forecasts for Spider-like and Planck-like experimental specifications and to investigate the sky-coverage optimization of the Spider-like case. We compare the forecast errors on r to the results from a similar multipole-based estimator which, by ignoring the mode-mixing, sets a lower limit on the achievable error on r. We find that an experiment with Spider-like specifications with fsky ˜ 0:02--0:2 could place a 2sigma r ≈ 0:014 bound (˜ 95% CL), which rises to 0:02 with an ℓ-dependent foreground residual left over from an assumed efficient component separation. For the Planck-like survey, a Galaxy-masked ( fsky = 0:75) sky would give 2sigmar ≈ 0:015, rising to ≈ 0:05 with the foreground residuals. We also use a novel information-based framework to compare how different generations of CMB experiments reveal information about the early universe, through their measurements of r. We also probe the epoch of recombination by investigating possible fluctuations in the free electron fraction Xe

  10. HIGH-PRECISION DYNAMICAL MASSES OF VERY LOW MASS BINARIES

    SciTech Connect

    Konopacky, Q. M.; Ghez, A. M.; McLean, I. S.; Barman, T. S.; Rice, E. L.; Bailey, J. I.; White, R. J.; Duchene, G. E-mail: ghez@astro.ucla.ed E-mail: barman@lowell.ed E-mail: white@chara.gsu.ed

    2010-03-10

    We present the results of a three year monitoring program of a sample of very low mass (VLM) field binaries using both astrometric and spectroscopic data obtained in conjunction with the laser guide star adaptive optics system on the W. M. Keck II 10 m telescope. Among the 24 systems studied, 15 have undergone sufficient orbital motion, allowing us to derive their relative orbital parameters and hence their total system mass. These measurements more than double the number of mass measurements for VLM objects, and include the most precise mass measurement to date (<2%). Among the 11 systems with both astrometric and spectroscopic measurements, six have sufficient radial velocity variations to allow us to obtain individual component masses. This is the first derivation of the component masses for five of these systems. Altogether, the orbital solutions of these low mass systems show a correlation between eccentricity and orbital period, consistent with their higher mass counterparts. In our primary analysis, we find that there are systematic discrepancies between our dynamical mass measurements and the predictions of theoretical evolutionary models (TUCSON and LYON) with both models either underpredicting or overpredicting the most precisely determined dynamical masses. These discrepancies are a function of spectral type, with late-M through mid-L systems tending to have their masses underpredicted, while one T-type system has its mass overpredicted. These discrepancies imply that either the temperatures predicted by evolutionary and atmosphere models are inconsistent for an object of a given mass, or the mass-radius relationship or cooling timescales predicted by the evolutionary models are incorrect. If these spectral-type trends are correct and hold into the planetary mass regime, the implication is that the masses of directly imaged extrasolar planets are overpredicted by the evolutionary models.

  11. 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. PMID:19044710

  12. 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.

  13. High-precision control of piezoelectric nanopositioning stages using hysteresis compensator and disturbance observer

    NASA Astrophysics Data System (ADS)

    Gu, Guo-Ying; Zhu, Li-Min; Su, Chun-Yi

    2014-10-01

    This paper proposes a novel high-performance control scheme with hysteresis compensator and disturbance observer for high-precision motion control of a nanopositioning stage driven by a piezoelectric stack actuator (PSA). In the developed control scheme, a real-time inverse hysteresis compensator (IHC) with the modified Prandtl-Ishlinskii model is firstly designed to compensate for the asymmetric hysteresis nonlinearity of the PSA. Due to the imperfect compensation, the dynamics behaviors of the PSA-actuated stage with the IHC can be treated as a linear dynamic system plus a lumped disturbance term. Owing to the unknown nature of this lumped disturbance term, a disturbance observer (DOB) is used as a means for disturbance rejection. With the DOB, a tracking controller is finally designed and implemented to stabilize the position error. To verify the proposed control scheme, a real-time experimental platform with a PSA-actuated nanopositioning stage is built, and extensive experimental tests are performed. The comparative experimental results demonstrate the effectiveness and improved performance of the developed control approach in terms of the maximum-value errors, root-mean-square-value errors and hysteresis compensation.

  14. New approach to high-precision Fourier transform spectrometer design

    NASA Astrophysics Data System (ADS)

    Brault, James W.

    1996-06-01

    Laser fringes have long been used to establish the x axis in interferometric spectrometry, but solutions for the intensity axis have been less satisfactory. Now we are seeing the rapid commercial development of low-cost, medium-speed, sigma-delta analog-to-digital converters developed for stereo audio applications. A single chip provides two channels of 20-bit precision at 50 kHz, a significant improvement over many current systems of much greater cost and complexity. But while the laser works in the spatial domain, this converter operates strictly in the time domain; it cannot be triggered. I have developed a bridge between these two domains, the adaptive digital filter, which not only permits us to use this converter to obtain measurements at arbitrary times but as a bonus shows us how to move much of the complexity of an interferometric-control and data-acquisition system from hardware to software. For example, flexible fringe subdivision (to increase the free spectral range) is easily obtained with a simple and efficient algorithm, completely free of laser ghosts. Compensation for drive velocity variation is also possible, requiring only a modest increase in computer memory.

  15. High Precision Photometry of Bright Transiting Exoplanet Hosts

    NASA Astrophysics Data System (ADS)

    Wilson, Maurice; Eastman, Jason; Johnson, John A.

    2016-01-01

    Within the past two decades, the successful search for exoplanets and the characterization of their physical properties have shown the immense progress that has been made towards finding planets with characteristics similar to Earth. For most exoplanets with a radius about the size of Earth, evaluating their physical properties, such as the mass, radius and equilibrium temperature, cannot be determined with satisfactory precision. The MINiature Exoplanet Radial Velocity Array (MINERVA) was recently built to obtain spectroscopic and photometric measurements to find, confirm, and characterize Earth-like exoplanets. MINERVA's spectroscopic survey targets the brightest, nearby stars which are well-suited to the array's capabilities, while its primary photometric goal is to search for transits around these bright targets. Typically, it is difficult to find satisfactory comparison stars within a telescope's field of view when the primary target is very bright. This issue is resolved by using one of MINERVA's telescopes to observe the primary bright star while the other telescopes observe a distinct field of view that contains satisfactory bright comparison stars. We describe the code used to identify nearby comparison stars, schedule the four telescopes, produce differential photometry from multiple telescopes, and show the first results from this effort.This work has been funded by the Ronald E. McNair Post-Baccalaureate Achievement Program, the ERAU Honors Program, the ERAU Undergraduate Research Spark Fund, and the Banneker Institute at the Harvard-Smithsonian Center for Astrophysics.

  16. High-speed precision weighing of pharmaceutical capsules

    NASA Astrophysics Data System (ADS)

    Bürmen, Miran; Pernuš, Franjo; Likar, Boštjan

    2009-11-01

    In this paper, we present a cost-effective method for fast and accurate in-line weighing of hard gelatin capsules based on the optimized capacitance sensor and real-time processing of the capsule capacitance profile resulting from 5000 capacitance measurements per second. First, the effect of the shape and size of the capacitive sensor on the sensitivity and stability of the measurements was investigated in order to optimize the performance of the system. The method was tested on two types of hard gelatin capsules weighing from 50 mg to 650 mg. The results showed that the capacitance profile was exceptionally well correlated with the capsule weight with the correlation coefficient exceeding 0.999. The mean precision of the measurements was in the range from 1 mg to 3 mg, depending on the size of the capsule and was significantly lower than the 5% weight tolerances usually used by the pharmaceutical industry. Therefore, the method was found feasible for weighing pharmaceutical hard gelatin capsules as long as certain conditions are met regarding the capsule fill properties and environment stability. The proposed measurement system can be calibrated by using only two or three sets of capsules with known weight. However, for most applications it is sufficient to use only empty and nominally filled capsules for calibration. Finally, a practical application of the proposed method showed that a single system is capable of weighing around 75 000 capsules per hour, while using multiple systems could easily increase the inspection rate to meet almost any requirements.

  17. High-precision timeline for Earth's most severe extinction.

    PubMed

    Burgess, Seth D; Bowring, Samuel; Shen, Shu-zhong

    2014-03-01

    The end-Permian mass extinction was the most severe loss of marine and terrestrial biota in the last 542 My. Understanding its cause and the controls on extinction/recovery dynamics depends on an accurate and precise age model. U-Pb zircon dates for five volcanic ash beds from the Global Stratotype Section and Point for the Permian-Triassic boundary at Meishan, China, define an age model for the extinction and allow exploration of the links between global environmental perturbation, carbon cycle disruption, mass extinction, and recovery at millennial timescales. The extinction occurred between 251.941 ± 0.037 and 251.880 ± 0.031 Mya, an interval of 60 ± 48 ka. Onset of a major reorganization of the carbon cycle immediately precedes the initiation of extinction and is punctuated by a sharp (3‰), short-lived negative spike in the isotopic composition of carbonate carbon. Carbon cycle volatility persists for ∼500 ka before a return to near preextinction values. Decamillenial to millennial level resolution of the mass extinction and its aftermath will permit a refined evaluation of the relative roles of rate-dependent processes contributing to the extinction, allowing insight into postextinction ecosystem expansion, and establish an accurate time point for evaluating the plausibility of trigger and kill mechanisms. PMID:24516148

  18. Design and realization of high precision FBG rain gauge based on triangle cantilever beam and its performance research

    NASA Astrophysics Data System (ADS)

    Lan, Ruo-ming; Cao, Yu-qiang

    2015-05-01

    A novel fiber Bragg grating (FBG) rain gauge is proposed in this paper to achieve high precision rainfall measurement. One core sensitive FBG, a temperature compensation FBG and a mechanical transition system construct this novel FBG rain gauge. Sensing principle of this FBG rain gauge is explained in detail, and its theoretical calculation model is also established, which shows that the relationship between center wavelength of sensitive FBG and external rainfall has very good linearity. To verify its detection performance, the calibration experiment on one prototype of this FBG rain gauge is carried out. After experiment data analysis, the detection precision of this FBG rain gauge is 15.4 μm which is almost two orders of magnitude higher than that of the existing rainfall measurement device. The experimental data confirm that this FBG rain gauge can achieve rainfall measurement with high precision.

  19. High-precision control of LSRM based X-Y table for industrial applications.

    PubMed

    Pan, J F; Cheung, Norbert C; Zou, Yu

    2013-01-01

    The design of an X-Y table applying direct-drive linear switched reluctance motor (LSRM) principle is proposed in this paper. The proposed X-Y table has the characteristics of low cost, simple and stable mechanical structure. After the design procedure is introduced, an adaptive position control method based on online parameter identification and pole-placement regulation scheme is developed for the X-Y table. Experimental results prove the feasibility and its priority over a traditional PID controller with better dynamic response, static performance and robustness to disturbances. It is expected that the novel two-dimensional direct-drive system find its applications in high-precision manufacture area.

  20. High Precision Fe Isotope Analysis in low Concentration Samples by High Resolution MC-ICPMS

    NASA Astrophysics Data System (ADS)

    Chung, C.; Wu, J.; You, C.

    2009-12-01

    Iron availability has been shown to be the main limitation factor for phytoplankton growth in the ocean. However, due to the limitation of analytical technique, the database of dissolved Fe concentrations and isotope ratio distribution in the ocean is still very limited. In particular, the iron sources to the ocean remain uncertain. Aeolian dust from the continental is considered as the primary source, also the digenetic dissolution at the continental margins is proposed to contribute significant portion of iron content of the sea surface water. The field of Fe isotope geochemistry has seen important developments in methodology and scope since the advent of Multi-Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICPMS). Although increasing the number of replicates in High Resolution MC-ICPMS reduces the uncertainty related to instability in instrumental mass bias and counting statistics, many other parameters include mass fractionation during column separation, matrix effect in ICPMS analysis and the presence of isobaric interferences can affect the precision and accuracy of Fe isotopic analyses. In this study, a high precision analytical method of Fe isotope measurement for low concentration samples was developed using HR-MC-ICPMS. Several parameters that may affect the accuracy and precision of 56Fe/54Fe result such as background, instrumental mass discrimination, isobaric interferences, type of introduction system and acid molarity were identified and evaluated. External precisions better than 0.04‰ for δ56Fe can be achieve using only 10ng of iron sample with APEX and X-cone as introduction system. Significant improvement in terms of sample size was made. This method can be applied on very low concentration samples such as coral and seawater.

  1. Models for High Precision Spacecraft and Planetary and Lunar Ephemerides

    NASA Astrophysics Data System (ADS)

    Standish, E. M.; Williams, J. G.

    2006-08-01

    The accuracies of the observational data fit by ephemerides are expected to increase by a full order of magnitude in the near future. Spacecraft ranging should improve from the present 1-meter level to perhaps 10 cm; directional measurements (VLBI, VLBA, etc.) will be accurate to 0.1 milliarcseconds or less; and Lunar Laser Ranging measurements will be taken near the 1 mm level. For such measurements to be fit by the ephemerides, a number of modeling improvements will be required for the ephemeris creation process. For the planetary ephemerides, it will be necessary to consider that many planets have distinct satellites (as opposed to being modeled with their barycenter); the perturbations of more than the just the present 300 asteroids must be considered, as well as some of the largest Kuiper belt objects; and the effect of the media through which the electromagnetic signals travel must be more accurately calibrated, possibly using dual or even triple frequency ranging. For the lunar ephemeris, many physical and observational features must be considered and further refined: thermal expansion of the retroreflectors, a possible lunar inner core, decrease of the solar mass, refined movements of the telescopes and retroreflectors. These are in addition to the presently accounted-for features: computation of the lunar librations; nonspherical gravitational fields of the moon, earth, and sun; earth and moon tidal effects; separate modeling of the rotating lunar mantle and fluid core; atmospheric time-delays depending on pressure, temperature, and humidity at the telescope; and relativistic effects upon each station's clock, position, and light-time. The lunar and planetary integration program is necessarily done now in quadruple precision. Relativity for the point-mass motions is complete through order 1/c**2; the need for the next order must be studied. Once the modeling does justice to the accuracies of the upcoming observations, a number of interesting tests will be

  2. High speed, precision motion strategies for lightweight structures

    NASA Technical Reports Server (NTRS)

    Book, Wayne J.

    1987-01-01

    Abstracts of published papers and dissertations generated during the reporting period are compiled. Work on fine motion control was completed. Specifically, real time control of flexible manipulator vibrations were experimentally investigated. A linear model based on the application of Lagrangian dynamics to a rigid body mode and a series of separable flexible modes was examined with respect to model order requirements, and modal candidate selection. State feedback control laws were implemented based upon linear quadratic regulator design. Specification of the closed loop poles in the regulator design process was obtained by inclusion of a prescribed degree of stability in the manipulator model. Work on gross motion planning and control is also summarized. A systematic method to symbolically derive the full nonlinear dynamic equations of motion of multi-link flexible manipulators was developed.

  3. High-Precision Diagnosis of Malfunctioning Apparatus allowed by Serendipity

    NASA Astrophysics Data System (ADS)

    Shaibani, Saami J.

    2010-02-01

    ``An electric brake has a resistance of 376 ohms and operates at 90 volts. If the only supply available is 115 volts, show how the brake can still be made to work.'' The preceding exercise is the theoretical counterpart of a practical problem involving a platform elevator for the physically-challenged. The elevator brake had been inoperable for a considerable period due to an intractable ambiguity, even after two independent technicians working together had established that some components might have been installed improperly. It so happened that the author was on handfootnotetextnote: during a visit to the educational institution concerned. and he suggested an experimental approach for a remedy that could be checked if some standard equipment were provided. Once this item was located, his testing confirmed the viability of the proposed remedy, resulting in a prompt repair and a much-needed return to service. This good outcome was achieved by integrating theory and practice to produce maximum synergy. )

  4. Experimental Technique for Producing and Recording Precise Particle Impacts on Transparent Window Materials

    NASA Technical Reports Server (NTRS)

    Gray, Perry; Guven, Ibrahim

    2016-01-01

    A new facility for making small particle impacts is being developed at NASA. Current sand/particle impact facilities are an erosion test and do not precisely measure and document the size and velocity of each of the impacting particles. In addition, evidence of individual impacts is often obscured by subsequent impacts. This facility will allow the number, size, and velocity of each particle to be measured and adjusted. It will also be possible to determine which particle produced damage at a given location on the target. The particle size and velocity will be measured by high speed imaging techniques. Information as to the extent of damage and debris from impacts will also be recorded. It will be possible to track these secondary particles, measuring size and velocity. It is anticipated that this additional degree of detail will provide input for erosion models and also help determine the impact physics of the erosion process. Particle impacts will be recorded at 90 degrees to the particle flight path and also from the top looking through the target window material.

  5. High-precision automatic online measurement system of engine block top surface holes

    NASA Astrophysics Data System (ADS)

    Yongqiang, Shi; Changku, Sun; Yukun, Ma; Hongxu, Duan; Peng, Wang

    2012-05-01

    The measurement of holes in the engine block top surface determines the general coupling effect of the engine. All of these holes are strictly restricted by the requirements of the dimensional tolerance and the geometrical tolerance, which determines the final engine quality. At present, these holes are measured mostly by the coordinate measuring machine (CMM) in the production line, and meeting the industry demands of automation, rapidity, and online testing with the method is difficult. A new rapid solution measuring the holes in the engine block top surface is proposed, which is based on the combination of multiple visual sensors. The flexible location method of the block is designed, and the global data fusion model based on multiple visual sensors is studied. Finally, the unified correction model of the lens distortion and the system inclination is proposed, and a revised system model with more precision is researched. The CMM measures the holes sizes and the spatial relationship between holes, and the data obtained are substituted into the global data fusion model to complete the system on-site rapid calibration. The experimental results show that the scheme is feasible. The measurement system can meet the production line needs of intelligence, rapidity, and high precision.

  6. Pointing Control System for a High Precision Flight Telescope

    SciTech Connect

    BENTLEY,ANTHONY E.; WILCOXEN,JEFFREY LEE

    2000-12-01

    A pointing control system is developed and tested for a flying gimbaled telescope. The two-axis pointing system is capable of sub-microradian pointing stability and high accuracy in the presence of large host vehicle jitter. The telescope also has high agility--it is capable of a 50-degree retarget (in both axes simultaneously) in less than 2 seconds. To achieve the design specifications, high-accuracy, high-resolution, two-speed resolvers were used, resulting in gimbal-angle measurements stable to 1.5 microradians. In addition, on-axis inertial angle displacement sensors were mounted on the telescope to provide host-vehicle jitter cancellation. The inertial angle sensors are accurate to about 100 nanoradians, but do not measure low frequency displacements below 2 Hz. The gimbal command signal includes host-vehicle attitude information, which is band-limited. This provides jitter data below 20 Hz, but includes a variable latency between 15 and 25 milliseconds. One of the most challenging aspects of this design was to combine the inertial-angle-sensor data with the less perfect information in the command signal to achieve maximum jitter reduction. The optimum blending of these two signals, along with the feedback compensation were designed using Quantitative Feedback Theory.

  7. High-precision horizontally directed force measurements for high dead loads based on a differential electromagnetic force compensation system

    NASA Astrophysics Data System (ADS)

    Vasilyan, Suren; Rivero, Michel; Schleichert, Jan; Halbedel, Bernd; Fröhlich, Thomas

    2016-04-01

    In this paper, we present an application for realizing high-precision horizontally directed force measurements in the order of several tens of nN in combination with high dead loads of about 10 N. The set-up is developed on the basis of two identical state-of-the-art electromagnetic force compensation (EMFC) high precision balances. The measurement resolution of horizontally directed single-axis quasi-dynamic forces is 20 nN over the working range of  ±100 μN. The set-up operates in two different measurement modes: in the open-loop mode the mechanical deflection of the proportional lever is an indication of the acting force, whereas in the closed-loop mode it is the applied electric current to the coil inside the EMFC balance that compensates deflection of the lever to the offset zero position. The estimated loading frequency (cutoff frequency) of the set-up in the open-loop mode is about 0.18 Hz, in the closed-loop mode it is 0.7 Hz. One of the practical applications that the set-up is suitable for is the flow rate measurements of low electrically conducting electrolytes by applying the contactless technique of Lorentz force velocimetry. Based on a previously developed set-up which uses a single EMFC balance, experimental, theoretical and numerical analyses of the thermo-mechanical properties of the supporting structure are presented.

  8. Ultrasmooth, highly spherical monocrystalline gold particles for precision plasmonics.

    PubMed

    Lee, You-Jin; Schade, Nicholas B; Sun, Li; Fan, Jonathan A; Bae, Doo Ri; Mariscal, Marcelo M; Lee, Gaehang; Capasso, Federico; Sacanna, Stefano; Manoharan, Vinothan N; Yi, Gi-Ra

    2013-12-23

    Ultrasmooth, highly spherical monocrystalline gold particles were prepared by a cyclic process of slow growth followed by slow chemical etching, which selectively removes edges and vertices. The etching process effectively makes the surface tension isotropic, so that spheres are favored under quasi-static conditions. It is scalable up to particle sizes of 200 nm or more. The resulting spherical crystals display uniform scattering spectra and consistent optical coupling at small separations, even showing Fano-like resonances in small clusters. The high monodispersity of the particles we demonstrate should facilitate the self-assembly of nanoparticle clusters with uniform optical resonances, which could in turn be used to fabricate optical metafluids. Narrow size distributions are required to control not only the spectral features but also the morphology and yield of clusters in certain assembly schemes.

  9. Development of a High Precision Body Surface Electrocardiogram

    NASA Astrophysics Data System (ADS)

    Inui, Shigeru; Toyosu, Yasushi; Akutagawa, Masatake; Kinouchi, Yosuke

    In the 12-lead electrocardiograph currently being used general medical practice, electrodes are positioned at 6 locations in the chest region and the cardiac potential is measured. This research increases the number of electrode to 124 at evenly-spaced intervals over the body surface of the chest, side and back. The commonly used band elimination filter is not used as a countermeasure for exclusion of the noise from such electrodes, and a body surface electrocardiograph has been developed that makes it possible to perform high-speed sampling of the cardiac potential at 80-100 times the conventional rate. From the sampling data obtained with high spatial resolution, maps and animations of the body surface potential distribution are created and displayed from the 1dimension waveform as well as from the 2dimensions/3dimensions waveforms.

  10. High-precision covariant one-boson-exchange potentials for np scattering below 350 MeV

    SciTech Connect

    Franz Gross; Alfred Stadler

    2007-09-10

    Using the Covariant Spectator Theory (CST), we have found One-Boson-Exchange (OBE) potentials that fit the 2006 world np data below 350 MeV with a chi2/Ndata very close to 1, for a total of 3788 data. Our potentials have significantly fewer adjustable parameters than previous high-precision potentials, and they also reproduce the experimental triton binding energy without introducing additional irreducible three-nucleon forces.

  11. Spectral band passes for a high precision satellite sounder.

    PubMed

    Kaplan, L D; Chahine, M T; Susskind, J; Searl, J E

    1977-02-01

    Atmospheric temperature soundings with significantly improved vertical resolution can be obtained from carefully chosen narrow band-pass measurements in the 4.3-microm band of CO(2) by taking advantage of the variation of the absorption coefficients, and thereby the weighting functions, with pressure and temperature. A set of channels has been found in the 4.2-microm region that is capable of yielding about 2-km vertical resolution in the troposphere. The concept of a complete system is presented for obtaining high resolution retrievals of temperature and water vapor distribution, as well as surface and cloud top temperatures, even in the presence of broken clouds.

  12. A high-precision pulse-width modulator source.

    SciTech Connect

    Lenkszus, F.; Laird, R.

    1999-09-30

    A novel high-resolution pulse-width modulator (PWM) is being developed for a new digital regulator for the Advanced Photon Source power converters. The circuit features 82-ps setability over an 80-{micro}s range. Our application requires a 50-{micro}s fill-scale range; therefore the 82-ps setability is equivalent to better than 19 bits. The circuit is presently implemented as a VME module and is an integral part of the digital regulator prototype. The design concept and performance results will be presented.

  13. Combination spindle-drive system for high precision machining

    DOEpatents

    Gerth, Howard L.

    1977-07-26

    A combination spindle-drive is provided for fabrication of optical quality surface finishes. Both the spindle-and-drive utilize the spindle bearings for support, thereby removing the conventional drive-means bearings as a source of vibration. An airbearing spindle is modified to carry at the drive end a highly conductive cup-shaped rotor which is aligned with a stationary stator to produce torque in the cup-shaped rotor through the reaction of eddy currents induced in the rotor. This arrangement eliminates magnetic attraction forces and all force is in the form of torque on the cup-shaped rotor.

  14. High speed precision motion strategies for lightweight structures

    NASA Technical Reports Server (NTRS)

    Book, Wayne J.

    1987-01-01

    Work during the recording period proceeded along the lines of the proposal, i.e., three aspects of high speed motion planning and control of flexible structures were explored: fine motion control, gross motion planning and control, and automation using light weight arms. In addition, modeling the large manipulator arm to be used in experiments and theory has lead to some contributions in that area. These aspects are reported below. Conference, workshop and journal submissions, and presentations related to this work were seven in number, and are listed. Copies of written papers and abstracts are included.

  15. A high-precision mechanical absolute-rotation sensor.

    PubMed

    Venkateswara, Krishna; Hagedorn, Charles A; Turner, Matthew D; Arp, Trevor; Gundlach, Jens H

    2014-01-01

    We have developed a mechanical absolute-rotation sensor capable of resolving ground rotation angle of less than 1 nrad/√Hz above 30 mHz and 0.2 nrad/√Hz above 100 mHz about a single horizontal axis. The device consists of a meter-scale beam balance, suspended by a pair of flexures, with a resonance frequency of 10.8 mHz. The center of mass is located 3 μm above the pivot, giving an excellent horizontal displacement rejection of better than 3 × 10(-5) rad/m. The angle of the beam is read out optically using a high-sensitivity autocollimator. We have also built a tiltmeter with better than 1 nrad/√Hz sensitivity above 30 mHz. Co-located measurements using the two instruments allowed us to distinguish between background rotation signal at low frequencies and intrinsic instrument noise. The rotation sensor is useful for rotational seismology and for rejecting background rotation signal from seismometers in experiments demanding high levels of seismic isolation, such as Advanced Laser Interferometer Gravitational-wave Observatory. PMID:24517804

  16. A high precision radiation-tolerant LVDT conditioning module

    NASA Astrophysics Data System (ADS)

    Masi, A.; Danzeca, S.; Losito, R.; Peronnard, P.; Secondo, R.; Spiezia, G.

    2014-05-01

    Linear variable differential transformer (LVDT) position sensors are widely used in particle accelerators and nuclear plants, thanks to their properties of contact-less sensing, radiation tolerance, infinite resolution, good linearity and cost efficiency. Many applications require high reading accuracy, even in environments with high radiation levels, where the conditioning electronics must be located several hundred meters away from the sensor. Sometimes even at long distances the conditioning module is still exposed to ionizing radiation. Standard off-the-shelf electronic conditioning modules offer limited performances in terms of reading accuracy and long term stability already with short cables. A radiation tolerant stand-alone LVDT conditioning module has been developed using Commercial Off-The-Shelf (COTS) components. The reading of the sensor output voltages is based on a sine-fit algorithm digitally implemented on an FPGA ensuring few micrometers reading accuracy even with low signal-to-noise ratios. The algorithm validation and board architecture are described. A full metrological characterization of the module is reported and radiation tests results are discussed.

  17. High precision moving magnet chopper for variable operation conditions

    NASA Astrophysics Data System (ADS)

    Aicher, Winfried; Schmid, Manfred

    1994-05-01

    In the context of an ESTEC technology contract, a Chopping Mechanism was developed and built with the Far Infrared and Submillimeter Telescope (FIRST) astronomy mission as a reference. The task of the mechanism is to tilt the subreflector of the telescope with an assumed mass of 2.5 kg about one chopping axis at nominal frequencies of up to 5 Hz and chopping angles of up to +/- 11.25 mrad with high efficiency (minimum time for position change). The chopping axis is required to run through the subreflector vertex. After performing a concept trade-off also considering the low operational temperatures in the 130 K range, a design using moving magnet actuators was found to be the favorite one. In addition, a bearing concept using flexible pivots was chosen to meet the high chopping accuracy required. With this approach, a very reliable design could be realized, since the actuators work without any mechanical contact between its moving and fixed parts, and the only bearings used are two flexible pivots supporting the subreflector mounting interface. The mechanism was completely built in titanium in a lightweight and stiff design. The moving magnet actuators were designed to meet the stringent requirements for minimum risetime (time necessary to move from one angular position to a new one) in the 20 msec range. The angular position and the corresponding chopping frequency as well can be arbitrarily selected by the user.

  18. A high-precision mechanical absolute-rotation sensor.

    PubMed

    Venkateswara, Krishna; Hagedorn, Charles A; Turner, Matthew D; Arp, Trevor; Gundlach, Jens H

    2014-01-01

    We have developed a mechanical absolute-rotation sensor capable of resolving ground rotation angle of less than 1 nrad/√Hz above 30 mHz and 0.2 nrad/√Hz above 100 mHz about a single horizontal axis. The device consists of a meter-scale beam balance, suspended by a pair of flexures, with a resonance frequency of 10.8 mHz. The center of mass is located 3 μm above the pivot, giving an excellent horizontal displacement rejection of better than 3 × 10(-5) rad/m. The angle of the beam is read out optically using a high-sensitivity autocollimator. We have also built a tiltmeter with better than 1 nrad/√Hz sensitivity above 30 mHz. Co-located measurements using the two instruments allowed us to distinguish between background rotation signal at low frequencies and intrinsic instrument noise. The rotation sensor is useful for rotational seismology and for rejecting background rotation signal from seismometers in experiments demanding high levels of seismic isolation, such as Advanced Laser Interferometer Gravitational-wave Observatory.

  19. A high-precision mechanical absolute-rotation sensor

    NASA Astrophysics Data System (ADS)

    Venkateswara, Krishna; Hagedorn, Charles A.; Turner, Matthew D.; Arp, Trevor; Gundlach, Jens H.

    2014-01-01

    We have developed a mechanical absolute-rotation sensor capable of resolving ground rotation angle of less than 1 nrad/sqrt{Hz} above 30 mHz and 0.2 nrad/sqrt{Hz} above 100 mHz about a single horizontal axis. The device consists of a meter-scale beam balance, suspended by a pair of flexures, with a resonance frequency of 10.8 mHz. The center of mass is located 3 μm above the pivot, giving an excellent horizontal displacement rejection of better than 3 × 10-5 rad/m. The angle of the beam is read out optically using a high-sensitivity autocollimator. We have also built a tiltmeter with better than 1 nrad/sqrt{Hz} sensitivity above 30 mHz. Co-located measurements using the two instruments allowed us to distinguish between background rotation signal at low frequencies and intrinsic instrument noise. The rotation sensor is useful for rotational seismology and for rejecting background rotation signal from seismometers in experiments demanding high levels of seismic isolation, such as Advanced Laser Interferometer Gravitational-wave Observatory.

  20. High precision moving magnet chopper for variable operation conditions

    NASA Technical Reports Server (NTRS)

    Aicher, Winfried; Schmid, Manfred

    1994-01-01

    In the context of an ESTEC technology contract, a Chopping Mechanism was developed and built with the Far Infrared and Submillimeter Telescope (FIRST) astronomy mission as a reference. The task of the mechanism is to tilt the subreflector of the telescope with an assumed mass of 2.5 kg about one chopping axis at nominal frequencies of up to 5 Hz and chopping angles of up to +/- 11.25 mrad with high efficiency (minimum time for position change). The chopping axis is required to run through the subreflector vertex. After performing a concept trade-off also considering the low operational temperatures in the 130 K range, a design using moving magnet actuators was found to be the favorite one. In addition, a bearing concept using flexible pivots was chosen to meet the high chopping accuracy required. With this approach, a very reliable design could be realized, since the actuators work without any mechanical contact between its moving and fixed parts, and the only bearings used are two flexible pivots supporting the subreflector mounting interface. The mechanism was completely built in titanium in a lightweight and stiff design. The moving magnet actuators were designed to meet the stringent requirements for minimum risetime (time necessary to move from one angular position to a new one) in the 20 msec range. The angular position and the corresponding chopping frequency as well can be arbitrarily selected by the user.

  1. High Precision Assembly of Thin Mirror X-ray Telescopes

    NASA Astrophysics Data System (ADS)

    Schattenburg, Mark

    Lightweight high resolution x-ray telescope optics are one of the key technologies under development for next-generation x-ray telescopes. The ultimate goal of this effort is to realize optics with spatial resolution rivaling Chandra (<1 arc-sec) but with collecting areas that are larger by orders of magnitude. In the USA several institutions, including GSFC, MSFC, Harvard-SAO, MIT and Northwest University are working on a variety of approaches to this problem. An excellent example is the NuSTAR x-ray telescope, which teamed Cal Tech, GSFC, Columbia University and LLNL to produce a superb set of hard x-ray optics. The telescope was composed of thousands of 0.2 mm-thick glass mirrors which were epoxied into place around a spindle structure. While very light weight, this process resulted in ~1 arc min resolution. We want to achieve ~100 times better with similar mass. A group at NASA GSFC has recently demonstrated an alternative thin-glass assembly procedure that has achieved ~7 arc sec resolution with x-ray tests. Further progress towards 1 arc-sec will require mirrors with improved figure, lower stress coatings, improved alignment, better metrology, and low stress bonding. Many of the difficulties with current mirror assembly practice stem from the use of epoxy as a bonding agent. Epoxy has many disadvantages, including high shrinkage, large CTE and creep, resin aging effects, water absorption, outgassing, low tensile strength, exothermicity, and requiring large amounts of time and/or heat to cure. These effects can cause errors that become â€oefrozen in― to the bond with no possibility of correction. We propose to investigate replacing epoxy with low temperature, low shrinkage solder alloys. We use these solders in conjunction with high power, millisec-long pulses from a fiber IR laser to deliver controlled amounts of heat into the bond area. We have demonstrated that laser pulses can be used to actuate carefully designed bonds by permanently compressing

  2. Creating high-stability high-precision bipolar trim power supply

    SciTech Connect

    Chen, Zhe; Merz, William A.

    2012-07-01

    Thomas Jefferson National Accelerator Facility (TJNAF) is founded by the US Department of Energy (DOE) office of science for the technology advancement and physics research in electron beam accelerator. This facility has the state of the art technology to carry out world-class cutting-edge experiments for the nucleus composition and atomic characteristics identification and exploration for the nature of the matter in the universe. A continuous wave electron beam is featured for such experiments, thus precise and stable trim power supply is required to meet such purpose. This paper demonstrates the challenges and solutions to design, assemble, fabrication and test such high-precision high-stability power supplies. This paper presents the novel design and first article test of the ±20A ±75V bipolar, 100ppm stability level current-regulated high-power trim power supplies for the beam manipulation. This special design can provide valuable documentation and reference values for future designs and special applications in particle accelerator power supply creation.

  3. High precision pointing with a multiline spectrometer at the VTT

    NASA Astrophysics Data System (ADS)

    Staiger, J.

    2012-12-01

    We are investigating the pointing quality of the VTT, Tenerife under the aspect of suitability for long-term heliosesimological observations. Tests have shown that thermal and mechanical loads within the telescope may create spurious image drifts with shift rates of up to 5 arcsec per hour. During daylong recordings this will reduce significantly the effective size of the field-of-view and may infer artificial lateral movements into the data. The underlying problem that not all image position offsets developing during a measurement may be compensated for is common to most high-resolution solar telescopes independently of the type of pointing system used. We are developing new approaches to address this problem which are to be tested in the near future at the VTT. The simulations established so far show that the problem may be reduced by more than 90 %.

  4. Precision high energy liner implosion experiments PHELIX [1

    SciTech Connect

    Reass, William A; Baca, David M; Griego, Jeffrey R; Reinovsky, Robert E; Rousculp, Christopher L; Turchi, Peter J

    2009-01-01

    This paper describes the hardware design of a small megajoule sized transformer coupled pulse power system utilized to drive hydrodynamic liner experiments with a nominal current capability of 10 megAmperes. The resulting liner velocities and characteristics provide properties of physics interest. The capacitor banks utilize the ''Atlas'' plastic cased 60 kV, 60 kJ capacitors [2] and railgaps [3]. The air insulated marx'S are configured to dive a multi-filar toroidal transformer. The 4:1 multi-filar toroidal transformer is mechanically part of a circular disc line and this feature results in an attractive inductance budget. Because of the compact size, re-usable transformer, and resulting low maintenance cost, shot rates can be high compared to other ''large'' machines or explosively driven hydrodynamic methods. The PHELIX modeling, construction status, and test results will also be provided.

  5. 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.

  6. High Precision Ti stable Isotope Measurement of Terrestrial Rocks

    NASA Astrophysics Data System (ADS)

    Millet, M. A.; Dauphas, N.; Williams, H. M.; Burton, K. W.; Nowell, G. M.

    2014-12-01

    Advances in multi-collection plasma source mass spectrometry have allowed the determination of stable isotope composition of transition metals to address questions relevant to both high and low temperature geochemistry. However, titanium has received only very limited attention. Here we present a new technique allowing the determination of the stable isotope composition of titanium in geological samples (d49Ti or deviation of the 49Ti/47Ti ratio from the OL-Ti in-house standard of reference) using double-spike methodology and high-resolution MC-ICP-MS. We have carried out a range analytical tests for a wide spectrum of samples matrices to demonstrate a external reproducibility of ±0.02‰ on the d49Ti while using as little as 150ng of natural Ti for a single analysis. We have analysed a comprehensive selection of mantle-derived samples covering a range of geodynamic contexts (MORB, IAB, OIB, adakites, eclogites, serpentines) and geographical distribution (MORB: Mid-Atlantic Ridge, Southwest Indian Ridge and Eastern Pacific Ridge; IAB: New Britain reference suite and Marianas Arc). The samples show a very limited range from -0.06‰ to +0.04‰ with a main mode at +0.004‰ relative to the OL-Ti standard. Average values for MORB, IAB and eclogites are similar within uncertainty and thus argue for limited mobility of Ti during subduction zone processes and homogeneity of the Ti stable isotope composition of the upper mantle. However, preliminary data for more evolved igneous rocks suggest that they display heavier Ti stable isotope compositions, which may reflect the removal of isotopically light Ti as a function of Fe-Ti oxide crystallisation. This is in good agreement with Ti being present in 5-fold and 6-fold coordination in basaltic melts and preferential uptake of 6-folded Ti by Ti-bearing oxides [1]. This dataset will be complemented by analysis of abyssal peridotites to confirm the homogeneity of the mantle as well as data for a range of ferromanganese crusts

  7. High-Precision Measurements of the Brightness Variation of Nereid

    NASA Astrophysics Data System (ADS)

    Terai, Tsuyoshi; Itoh, Yoichi

    2013-04-01

    Nereid, the outer satellite of Neptune, has a highly eccentric prograde orbit with a semimajor axis of larger than 200 in units of Neptune's radius, and is classified as an irregular satellite. Although the capture origin of irregular satellites has been widely accepted, several previous studies suggest that Nereid was formed in the circumplanetary disk of Neptune and ejected outward to the present location by Triton. A series of our photometric observations confirm that Nereid's rotation period, 11.5 hr, is stable and nonchaotic, as indicated by Grav, Holman, and Kavelaars (2003, ApJ, 591, L71). The optical colors of Nereid are indistinguishable from those of trans-Neptunian objects and Centaurs, especially from these objects with neutral colors. We also found the consistency of Nereid's rotation period based on the size-rotation distribution of small outer bodies. It is likely that Nereid originated as an immigrant body captured from the heliocentric orbit that was 4-5 AU away from Neptune's orbit.

  8. A research of a high precision multichannel data acquisition system

    NASA Astrophysics Data System (ADS)

    Zhong, Ling-na; Tang, Xiao-ping; Yan, Wei

    2013-08-01

    The output signals of the focusing system in lithography are analog. To convert the analog signals into digital ones which are more flexible and stable to process, a desirable data acquisition system is required. The resolution of data acquisition, to some extent, affects the accuracy of focusing. In this article, we first compared performance between the various kinds of analog-to-digital converters (ADC) available on the market at the moment. Combined with the specific requirements (sampling frequency, converting accuracy, numbers of channels etc) and the characteristics (polarization, amplitude range etc) of the analog signals, the model of the ADC to be used as the core chip in our hardware design was determined. On this basis, we chose other chips needed in the hardware circuit that would well match with ADC, then the overall hardware design was obtained. Validation of our data acquisition system was verified through experiments and it can be demonstrated that the system can effectively realize the high resolution conversion of the multi-channel analog signals and give the accurate focusing information in lithography.

  9. High Resolution Airborne Digital Imagery for Precision Agriculture

    NASA Technical Reports Server (NTRS)

    Herwitz, Stanley R.

    1998-01-01

    The Environmental Research Aircraft and Sensor Technology (ERAST) program is a NASA initiative that seeks to demonstrate the application of cost-effective aircraft and sensor technology to private commercial ventures. In 1997-98, a series of flight-demonstrations and image acquisition efforts were conducted over the Hawaiian Islands using a remotely-piloted solar- powered platform (Pathfinder) and a fixed-wing piloted aircraft (Navajo) equipped with a Kodak DCS450 CIR (color infrared) digital camera. As an ERAST Science Team Member, I defined a set of flight lines over the largest coffee plantation in Hawaii: the Kauai Coffee Company's 4,000 acre Koloa Estate. Past studies have demonstrated the applications of airborne digital imaging to agricultural management. Few studies have examined the usefulness of high resolution airborne multispectral imagery with 10 cm pixel sizes. The Kodak digital camera integrated with ERAST's Airborne Real Time Imaging System (ARTIS) which generated multiband CCD images consisting of 6 x 106 pixel elements. At the designated flight altitude of 1,000 feet over the coffee plantation, pixel size was 10 cm. The study involved the analysis of imagery acquired on 5 March 1998 for the detection of anomalous reflectance values and for the definition of spectral signatures as indicators of tree vigor and treatment effectiveness (e.g., drip irrigation; fertilizer application).

  10. High Precision Pulsar Timing: Effects of ISM Correction Schemes

    NASA Astrophysics Data System (ADS)

    Kunert, Willie; Verbiest, J. P. W.; Shannon, R.; Stinebring, D.

    2012-01-01

    Pulsar timing arrays are one of the leading methods in the search for gravitational waves (GWs). However a significant issue facing this method is the effect of the interstellar medium (ISM). There are multiple methodologies being used to correct for these effects but their efficacy has not been carefully studied. We conducted an initial study of biases induced by correcting for the interstellar medium. We simulated times of arrival (TOAs) with white noise and added ISM delays. We measure the ISM effects as is done with normal data, and created a model of these effects using polynomial fitting. This modeling method is most commonly used in the European Pulsar Timing Array. We then remove these measured ISM effects and compare final and initial TOAs. Ideally they should be the same; however, the differences between the 'corrected' TOAs and original TOAs reveal the weaknesses of this method. In preliminary results we concluded that the higher order polynomials do a better job, yet there is a limit as to how high an order one can use. We also found no significant systematic parameter bias induced by using this method. However, it is clear that certain parameters are more affected by this process of correction. The parameters most affected were the frequency and frequency derivative of the pulsar, but biases in these parameters are not important because the power due to them gets removed in the standard timing analysis. We are continuing this research by comparing and contrasting ISM correction schemes, as well as studying the actual behavior of the ISM in more detail. This research is supported by an NSF-PIRE and an NSF-AST grant.

  11. Development of a facility for high-precision irradiation of cells with carbon ions

    SciTech Connect

    Goethem, Marc-Jan van; Niemantsverdriet, Maarten; Brandenburg, Sytze; Langendijk, Johannes A.; Coppes, Robert P.; Luijk, Peter van

    2011-01-15

    the irradiation of cell samples with the specified accuracy. Measurements of the transverse and longitudinal dose distribution showed that the dose variation over the sample volume was {+-}0.8% and {+-}0.7% in the lateral and longitudinal directions, respectively. The track-averaged LET of 132{+-}10 keV/{mu}m and dose-averaged LET of 189{+-}15 keV/{mu}m at the position of the sample were obtained from a GEANT4 simulation, which was validated experimentally. Three separately measured cell-survival curves yielded nearly identical results. Conclusions: With the new facility, high-precision carbon-ion irradiations of biological samples can be performed with highly reproducible results.

  12. Design of high precision motor driving system for circular scanning ultrasonic endoscopic imaging equipment

    NASA Astrophysics Data System (ADS)

    Deng, Haoran; Bai, Baoping; Chen, Xiaodong; Zhao, Qiang; Li, Yanan; Wang, Yi; Yu, Daoyin

    2013-12-01

    This paper describes the development of a motor driving system for circular scanning ultrasonic endoscopic imaging equipment. It was designed to guarantee the motor rotating at a relatively constant speed in load fluctuation conditions, which result from the bending and twisting of the flexible shaft which connects the probe to the motor. A hardware feedback circuit based on Frequency-To-Voltage Converter LM331 and Step-Down Voltage Regulator LM2576-ADJ was designed to ensure steady rotation of motor in load fluctuation conditions, and a D/A module offered by MCU was used to regulate the real-time rotary speed. The feedback response cycle is about 20 μs according to theoretical analysis. Experimental results show that the maximum error is +/-1 r/min under the normal running environment (300 ~1500 r/min) and load fluctuation conditions, which means the average instability is reduced to 0.11% as compared with that of the motor drive simply based on MCU which is 0.94%. Both theoretical analysis and experimental results indicate that the motor driving system has high accuracy, fast response, excellent reliability and good versatility and portability, and can precisely guarantee the smooth movement of load-changing PMW (Pulse Width Modulation) motor, so as to ensure the imaging quality, and can effectively improve the efficiency and accuracy of the diagnosis.

  13. Atomic Hydrogen as High-Precision Field Standard for High-Field EPR

    PubMed Central

    Stoll, Stefan; Ozarowski, Andrew; Britt, R. David; Angerhofer, Alexander

    2010-01-01

    We introduce atomic hydrogen trapped in an octaisobutylsilsesquioxane nanocage (H@iBuT8) as a new molecular high-precision magnetic field standard for high-field EPR spectroscopy of organic radicals and other systems with signals around g = 2. Its solid-state EPR spectrum consists of two narrow lines separated by about 51 mT and centered at g ≈ 2. The isotropic g factor is 2.00294(3) and essentially temperature independent. The isotopic 1H hyperfine coupling constant is 1416.8(2) MHz below 70 K and decreases slightly with increasing temperature to 1413.7(1) MHz at room temperature. The spectrum of the standard does not overlap with those of most organic radicals, and it can be easily prepared and is stable at room temperature. PMID:20813570

  14. 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.

  15. Research on high precision equal-angle scanning method in rotary kiln temperature measurement system

    NASA Astrophysics Data System (ADS)

    Dai, Shaosheng; Guo, Zhongyuan; You, Changhui; Liu, Jinsong; Cheng, Yang; Tang, Huaming

    2016-05-01

    Aiming at traditional horizontal equal-angle scanning method's disadvantage of measurement error, a high precision equal-angle scanning method is proposed, the proposed method establishes a tilt scanning model by the following steps: introducing height variable, precisely calculating the viewing angle, building scanning model. The model is used to calculate scanning position on rotary kiln's surface, which helps to locate and track temperature variation. The experiment shows that the proposed method can effectively improve the precision of temperature spots' location on the rotary kiln surface.

  16. Precision laboratory apparatus for high temperature compression molding of glass lenses

    NASA Astrophysics Data System (ADS)

    Firestone, Gregory C.; Jain, Anurag; Yi, Allen Y.

    2005-06-01

    Recently, compression molding of glass aspherical lenses has become a viable manufacturing process for precision optical devices. In this research, an apparatus designed for precision compression molding of glass optics was constructed. The apparatus design was governed by two primary goals: molding process control and property measurement of common optical glasses such as BK 7, SK5, and soda lime glass. Equipped with high precision components, a closed loop feedback control and a unique force adaptive scheme, the apparatus was successfully used for glass property measurement tests. Moreover, the performance of the apparatus was also validated using selected microlens molding experiments.

  17. High-precision three-dimensional coordinate measurement with subwavelength-aperture-fiber point diffraction interferometer

    NASA Astrophysics Data System (ADS)

    Wang, Daodang; Xu, Yangbo; Chen, Xixi; Wang, Fumin; Kong, Ming; Zhao, Jun

    2014-11-01

    To overcome the accuracy limitation due to the machining error of standard parts in measurement system, a threedimensional coordinate measurement method with subwavelength-aperture-fiber point diffraction interferometer (PDI) is proposed, in which the high-precision measurement standard is obtained from the ideal point-diffracted spherical wavefront instead of standard components. On the basis of the phase distribution demodulated from point-diffraction interference field, high-precision three-dimensional coordinate measurement is realized with numerical iteration optimization algorithm. The subwavelength-aperture fiber is used as point-diffraction source to get precise and highenergy spherical wavefront within high aperture angle range, by which the conflict between diffraction wave angle and energy in traditional PDI can be avoided. Besides, a double-iterative method based on Levenbery-Marquardt algorithm is proposed to realize precise reconstruct three-dimensional coordinate. The analysis shows that the proposed method can reach the measurement precision better than microns within a 200×200×300 (in unit of mm) working volume. This measurement method does not rely on the initial iteration value in numerical coordinate reconstruction, and also has high measurement precision, large measuring range, fast processing speed and preferable anti-noise ability. It is of great practicality for measurement of three-dimensional coordinate and calibration of measurement system.

  18. [Research on a novel high-precision methane concentration detection system].

    PubMed

    Song, Lin-li; Zhou, Han-chang; Zhang, Zhi-jie

    2014-12-01

    In the gas concentration detection process using the characteristic spectrum absorption method, in order to improve the detection accuracy of the gas concentration, it often has to use the high-quality narrowband modulated laser and modulate wavelength to align with the characteristic absorption peaks of measured gas. But by this way, the cost of the laser and system requirements will be greatly increased. To use the existing portable, low-cost semiconductor laser conditions, at the same time it can obtain higher precision, conversion window differential absorption optical structure and the algorithm of differential characteristic absorption ratio was designed. Selection reason of position of the wavelength characteristic was analyzed, and steps to implement the processing algorithm were given. Systematically utilizing the combination method of conversion window and absorption gas chamber, by the method for calculating the ratio of the light intensity response, the light intensity from non-characteristic absorption peak position was divided out. So it achieved a similar detecting effect was achieved that used a narrow-band laser aligned to the feature absorption peak position. Experiments adopted MW-IR-1650 infrared laser, type SSM17-2 stepper motor control module, C30659 infrared detectors, and other devices. In the experiments, different concentrations of methane gas were tested, and experimental results show that the relative error of measurement was less than 2.0% within the range from 200 to 5000 ppm. In summary, it's proved that the system has high accuracy and stability.

  19. HIGH PRECISION K-SHELL PHOTOABSORPTION CROSS SECTIONS FOR ATOMIC OXYGEN: EXPERIMENT AND THEORY

    SciTech Connect

    McLaughlin, B. M.; Ballance, C. P.; Bowen, K. P.; Gardenghi, D. J.; Stolte, W. C. E-mail: ballance@physics.auburn.edu E-mail: dgardenghi@gmail.com

    2013-07-01

    Photoabsorption of atomic oxygen in the energy region below the 1s {sup -1} threshold in X-ray spectroscopy from Chandra and XMM-Newton is observed in a variety of X-ray binary spectra. Photoabsorption cross sections determined from an R-matrix method with pseudo-states and new, high precision measurements from the Advanced Light Source (ALS) are presented. High-resolution spectroscopy with E/{Delta}E Almost-Equal-To 4250 {+-} 400 was obtained for photon energies from 520 eV to 555 eV at an energy resolution of 124 {+-} 12 meV FWHM. K-shell photoabsorption cross section measurements were made with a re-analysis of previous experimental data on atomic oxygen at the ALS. Natural line widths {Gamma} are extracted for the 1s {sup -1}2s {sup 2}2p {sup 4}({sup 4} P)np {sup 3} P Degree-Sign and 1s {sup -1}2s {sup 2}2p {sup 4}({sup 2} P)np {sup 3} P Degree-Sign Rydberg resonances series and compared with theoretical predictions. Accurate cross sections and line widths are obtained for applications in X-ray astronomy. Excellent agreement between theory and the ALS measurements is shown which will have profound implications for the modeling of X-ray spectra and spectral diagnostics.

  20. High precision quantum-chemical treatment of adsorption: Benchmarking physisorption of molecular hydrogen on graphane.

    PubMed

    Usvyat, Denis

    2015-09-14

    A multilevel hierarchical ab initio protocol for calculating adsorption on non-conducting surfaces is presented. It employs fully periodic treatment, which reaches local Møller-Plesset perturbation theory of second order (MP2) with correction for the basis set incompleteness via the local F12 technique. Post-MP2 corrections are calculated using finite clusters. That includes the coupled cluster treatment in the local and canonical frameworks (up to perturbative quadruples) and correlated core (with MP2). Using this protocol, the potential surface of hydrogen molecules adsorbed on graphane was computed. According to the calculations, hydrogen molecules are adsorbed on graphane in a perpendicular to the surface orientation with the minimum of the potential surface of around -3.6 kJ/mol located at the distance of 3.85 Å between the bond center of the hydrogen molecule and the mid-plane of graphane. The adsorption sites along the path from the downward-pointing carbon to the ring center of the graphane are energetically virtually equally preferable, which can enable nearly free translations of hydrogen molecules along these paths. Consequently, the hydrogen molecules on graphane most likely form a non-commensurate monolayer. The analysis of the remaining errors reveals a very high accuracy of the computed potential surface with an error bar of a few tenths of a kJ/mol. The obtained results are a high-precision benchmark for further theoretical and experimental studies of hydrogen molecules interacting with graphane.

  1. High precision quantum-chemical treatment of adsorption: Benchmarking physisorption of molecular hydrogen on graphane

    NASA Astrophysics Data System (ADS)

    Usvyat, Denis

    2015-09-01

    A multilevel hierarchical ab initio protocol for calculating adsorption on non-conducting surfaces is presented. It employs fully periodic treatment, which reaches local Møller-Plesset perturbation theory of second order (MP2) with correction for the basis set incompleteness via the local F12 technique. Post-MP2 corrections are calculated using finite clusters. That includes the coupled cluster treatment in the local and canonical frameworks (up to perturbative quadruples) and correlated core (with MP2). Using this protocol, the potential surface of hydrogen molecules adsorbed on graphane was computed. According to the calculations, hydrogen molecules are adsorbed on graphane in a perpendicular to the surface orientation with the minimum of the potential surface of around -3.6 kJ/mol located at the distance of 3.85 Å between the bond center of the hydrogen molecule and the mid-plane of graphane. The adsorption sites along the path from the downward-pointing carbon to the ring center of the graphane are energetically virtually equally preferable, which can enable nearly free translations of hydrogen molecules along these paths. Consequently, the hydrogen molecules on graphane most likely form a non-commensurate monolayer. The analysis of the remaining errors reveals a very high accuracy of the computed potential surface with an error bar of a few tenths of a kJ/mol. The obtained results are a high-precision benchmark for further theoretical and experimental studies of hydrogen molecules interacting with graphane.

  2. High precision quantum-chemical treatment of adsorption: Benchmarking physisorption of molecular hydrogen on graphane

    SciTech Connect

    Usvyat, Denis

    2015-09-14

    A multilevel hierarchical ab initio protocol for calculating adsorption on non-conducting surfaces is presented. It employs fully periodic treatment, which reaches local Møller-Plesset perturbation theory of second order (MP2) with correction for the basis set incompleteness via the local F12 technique. Post-MP2 corrections are calculated using finite clusters. That includes the coupled cluster treatment in the local and canonical frameworks (up to perturbative quadruples) and correlated core (with MP2). Using this protocol, the potential surface of hydrogen molecules adsorbed on graphane was computed. According to the calculations, hydrogen molecules are adsorbed on graphane in a perpendicular to the surface orientation with the minimum of the potential surface of around −3.6 kJ/mol located at the distance of 3.85 Å between the bond center of the hydrogen molecule and the mid-plane of graphane. The adsorption sites along the path from the downward-pointing carbon to the ring center of the graphane are energetically virtually equally preferable, which can enable nearly free translations of hydrogen molecules along these paths. Consequently, the hydrogen molecules on graphane most likely form a non-commensurate monolayer. The analysis of the remaining errors reveals a very high accuracy of the computed potential surface with an error bar of a few tenths of a kJ/mol. The obtained results are a high-precision benchmark for further theoretical and experimental studies of hydrogen molecules interacting with graphane.

  3. Experimental design: computer simulation for improving the precision of an experiment.

    PubMed

    van Wilgenburg, Henk; Zillesen, Piet G van Schaick; Krulichova, Iva

    2004-06-01

    An interactive computer-assisted learning program, ExpDesign, that has been developed for simulating animal experiments, is introduced. The program guides students through the steps for designing animal experiments and estimating optimal sample sizes. Principles are introduced for controlling variation, establishing the experimental unit, selecting randomised block and factorial experimental designs, and applying the appropriate statistical analysis. Sample Power is a supporting tool that visualises the process of estimating the sample size. The aim of developing the ExpDesign program has been to make biomedical research workers more familiar with some basic principles of experimental design and statistics and to facilitate discussions with statisticians.

  4. 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.

  5. Machine Vision for High Precision Volume Measurement Applied to Levitated Containerless Materials Processing

    NASA Technical Reports Server (NTRS)

    Bradshaw, R. C.; Schmidt, D. P.; Rogers, J. R.; Kelton, K. F.; Hyers, R. W.

    2005-01-01

    By combining the best practices in optical dilatometry with new numerical methods, a high-speed and high precision technique has been developed to measure volume of levitated, containerlessly processed samples with sub- pixel resolution. Containerless processing provides the ability to study highly reactive materials without the possibility of contamination affecting thermo-physical properties. Levitation is a common technique used to isolate a sample as it is being processed. Noncontact optical measurement of thermo-ophysical properties is very important as traditional measuring methods cannot be used. Modern, digitally recorded images require advanced numerical routines to recover the sub-pixel locations of sample edges and, in turn produce high precision measurements.

  6. Use of terrestrial laser scanning technology for long term high precision deformation monitoring.

    PubMed

    Vezočnik, Rok; Ambrožič, Tomaž; Sterle, Oskar; Bilban, Gregor; Pfeifer, Norbert; Stopar, Bojan

    2009-01-01

    The paper presents a new methodology for high precision monitoring of deformations with a long term perspective using terrestrial laser scanning technology. In order to solve the problem of a stable reference system and to assure the high quality of possible position changes of point clouds, scanning is integrated with two complementary surveying techniques, i.e., high quality static GNSS positioning and precise tacheometry. The case study object where the proposed methodology was tested is a high pressure underground pipeline situated in an area which is geologically unstable.

  7. High-precision thickness setting models for titanium alloy plate cold rolling without tension

    NASA Astrophysics Data System (ADS)

    Wang, Xiaochen; Yang, Quan; He, Fei; Sun, Youzhao; Xiao, Huifang

    2015-03-01

    Due to its highly favorable physical and chemical properties, titanium and titanium alloy are widely used in a variety of industries. Because of the low output of a single batch, plate cold rolling without tension is the most common rolling production method for titanium alloy. This method is lack of on-line thickness closed-loop control, with carefully thickness setting models for precision. A set of high-precision thickness setting models are proposed to suit the production method. Because of frequent variations in rolling specification, a model structural for the combination of analytical models and statistical models is adopted to replace the traditional self-learning method. The deformation resistance and friction factor, the primary factors which affect model precision, are considered as the objectives of statistical modeling. Firstly, the coefficient fitting of deformation resistance analytical model based on over-determined equations set is adopted. Additionally, a support vector machine(SVM) is applied to the modeling of the deformation resistance and friction factor. The setting models are applied to a 1450 plate-coiling mill for titanium alloy plate rolling, and then thickness precision is found consistently to be within 3%, exceeding the precision of traditional setting models with a self-learning method based on a large number of stable rolling data. Excellent application performance is obtained. The proposed research provides a set of high-precision thickness setting models which are well adapted to the characteristics of titanium alloy plate cold rolling without tension.

  8. Research on machining error compensation in high-precision surface grinding machine for optical aspheric elements

    NASA Astrophysics Data System (ADS)

    Ke, Xiaolong; Guo, Yinbiao; Zhang, Shihan; Huang, Hao

    2010-10-01

    Using aspheric component in optical system can correct optical aberration, acquire high imaging quality, improve the optical characteristic, simplify system structure, and reduce system volume. Nowadays, high-precision surface grinding machine is an important approach to processing optical aspheric elements. However, because of the characteristics of optical aspheric elements, the processing method makes a higher demand to whole performance of surface grinding machine, and hardly to achieve ideal machining effect. Taking high generality and efficiency into account, this paper presents a compensation method for machining errors of high-precision surface grinding machine, which bases on optical aspheric elements, to achieve high-precision machining for all kinds of optical aspheric elements. After compensation, the machining accuracy of grinding machine could reach 2um/200×200mm. The research bases on NC surface grinding machine which is self developed. First of all, this paper introduces machining principle for optical aspheric elements on the grinding machine. And then error sources which producing errors are analyzed. By contacting and non-contacting measurement sensors, measurement software which is self designed realizes on-position measure for grinded workpiece, then fits surface precision and machining errors. Through compensation software for machining error which is self designed, compensation algorithm is designed and translated compensation data into G-code for the high-precision grinding machine to achieve compensation machining. Finally, by comparison between machining error compensation before and after processing, the experiments for this purpose are done to validate the compensation machining accuracy.

  9. Methods for high precision 14C AMS measurement of atmospheric CO2 at LLNL

    SciTech Connect

    Graven, H D; Guilderson, T P; Keeling, R F

    2006-10-18

    Development of {sup 14}C analysis with precision better than 2{per_thousand} has the potential to expand the utility of {sup 14}CO{sub 2} measurements for carbon cycle investigations as atmospheric gradients currently approach traditional measurement precision of 2-5{per_thousand}. The AMS facility at the Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, produces high and stable beam currents that enable efficient acquisition times for large numbers of {sup 14}C counts. One million {sup 14}C atoms can be detected in approximately 25 minutes, suggesting that near 1{per_thousand} counting precision is economically feasible at LLNL. The overall uncertainty in measured values is ultimately determined by the variation between measured ratios in several sputtering periods of the same sample and by the reproducibility of replicate samples. Experiments on the collection of one million counts on replicate samples of CO{sub 2} extracted from a whole air cylinder show a standard deviation of 1.7{per_thousand} in 36 samples measured over several wheels. This precision may be limited by the reproducibility of Oxalic Acid I standard samples, which is considerably poorer. We outline the procedures for high-precision sample handling and analysis that have enabled reproducibility in the cylinder extraction samples at the <2{per_thousand} level and describe future directions to continue increasing measurement precision at LLNL.

  10. Experimental approaches for addressing fundamental biological questions in living, functioning cells with single molecule precision

    PubMed Central

    Lenn, Tchern; Leake, Mark C.

    2012-01-01

    In recent years, single molecule experimentation has allowed researchers to observe biological processes at the sensitivity level of single molecules in actual functioning, living cells, thereby allowing us to observe the molecular basis of the key mechanistic processes in question in a very direct way, rather than inferring these from ensemble average data gained from traditional molecular and biochemical techniques. In this short review, we demonstrate the impact that the application of single molecule bioscience experimentation has had on our understanding of various cellular systems and processes, and the potential that this approach has for the future to really address very challenging and fundamental questions in the life sciences. PMID:22773951

  11. High precision predictions for exclusive VH production at the LHC

    SciTech Connect

    Li, Ye; Liu, Xiaohui

    2014-06-04

    We present a resummation-improved prediction for pp → VH + 0 jets at the Large Hadron Collider. We focus on highly-boosted final states in the presence of jet veto to suppress the tt¯ background. In this case, conventional fixed-order calculations are plagued by the existence of large Sudakov logarithms αnslogm(pvetoT/Q) for Q ~ mV + mH which lead to unreliable predictions as well as large theoretical uncertainties, and thus limit the accuracy when comparing experimental measurements to the Standard Model. In this work, we show that the resummation of Sudakov logarithms beyond the next-to-next-to-leading-log accuracy, combined with the next-to-next-to-leading order calculation, reduces the scale uncertainty and stabilizes the perturbative expansion in the region where the vector bosons carry large transverse momentum. Thus, our result improves the precision with which Higgs properties can be determined from LHC measurements using boosted Higgs techniques.

  12. Laser ablation and high precision patterning of biomaterials and intraocular lenses

    NASA Astrophysics Data System (ADS)

    Serafetinides, A. A.; Spyratou, E.; Makropoulou, M.

    2010-10-01

    The use of intraocular lenses (IOL) is the most promising method for restoring excellent vision in cataract surgery. In addition, multifocal intraocular lenses for good distant and near vision are investigated. Several new materials, techniques and patterns are studied for the formation and etching of intraocular lenses in order to improve their optical properties and reduce the diffractive aberrations. As pulsed laser ablation is well established as a universal tool for surface processing of organic polymer materials, this study was focused in using laser ablation with short and ultra short laser pulses for surface modification of PMMA and intraocular lenses, instead of using other conventional techniques. The main advantage of using very short laser pulses, e.g. of ns, ps or fs duration, is that heat diffusion into the polymer material is negligible. As a result high precision patterning of the sample, without thermal damage of the surroundings, becomes possible. In this study, laser ablation was performed using commercially available hydrophobic acrylic IOLs, hydrophilic acrylic IOLs, and PMMA IOLs, with various diopters. We investigated the ablation efficiency and the phenomenology of the etched patterns by testing the ablation rate, versus laser energy fluence, at several wavelengths and the surface modification with atomic force microscopy (AFM), or scanning electron microscopy (SEM). The irradiated polymers have different optical properties, at the applied wavelengths, and therefore, present different ablation behaviour and morphology of the laser ablated crater walls and surrounding surfaces. The experimental results, some theoretical assumptions for mathematical modeling of the relevant ablation mechanisms are discussed.

  13. Gradient-based high precision alignment of cryo-electron subtomograms

    PubMed Central

    Xu, Min; Alber, Frank

    2014-01-01

    Whole cell cryo-electron tomography emerges as an important component for structural system biology approaches. It allows the localization and structural characterization of macromolecular complexes in near living conditions. However, the method is hampered by low resolution, missing data and low signal-to-noise ratio (SNR). To overcome some of these difficulties one can align and average a large set of subtomograms. Existing alignment methods are mostly based on an exhaustive scanning and sampling of all but discrete relative rotations and translations of one subtomogram with respect to the other. In this paper, we propose a gradient-guided alignment method based on two subtomogram similarity measures. We also propose a stochastic parallel optimization that increases significantly the efficiency for the simultaneous refinement of a set of alignment candidates. Results on simulated data of model complexes and experimental structures of protein complexes show that even for highly distorted subtomograms and with only a small number of very sparsely distributed initial alignment seeds, our method can accurately recover true transformations with a significantly higher precision than scanning based alignment methods. PMID:25068871

  14. Precision of FLEET Velocimetry Using High-Speed CMOS Camera Systems

    NASA Technical Reports Server (NTRS)

    Peters, Christopher J.; Danehy, Paul M.; Bathel, Brett F.; Jiang, Naibo; Calvert, Nathan D.; Miles, Richard B.

    2015-01-01

    Femtosecond laser electronic excitation tagging (FLEET) is an optical measurement technique that permits quantitative velocimetry of unseeded air or nitrogen using a single laser and a single camera. In this paper, we seek to determine the fundamental precision of the FLEET technique using high-speed complementary metal-oxide semiconductor (CMOS) cameras. Also, we compare the performance of several different high-speed CMOS camera systems for acquiring FLEET velocimetry data in air and nitrogen free-jet flows. The precision was defined as the standard deviation of a set of several hundred single-shot velocity measurements. Methods of enhancing the precision of the measurement were explored such as digital binning (similar in concept to on-sensor binning, but done in post-processing), row-wise digital binning of the signal in adjacent pixels and increasing the time delay between successive exposures. These techniques generally improved precision; however, binning provided the greatest improvement to the un-intensified camera systems which had low signal-to-noise ratio. When binning row-wise by 8 pixels (about the thickness of the tagged region) and using an inter-frame delay of 65 microseconds, precisions of 0.5 meters per second in air and 0.2 meters per second in nitrogen were achieved. The camera comparison included a pco.dimax HD, a LaVision Imager scientific CMOS (sCMOS) and a Photron FASTCAM SA-X2, along with a two-stage LaVision HighSpeed IRO intensifier. Excluding the LaVision Imager sCMOS, the cameras were tested with and without intensification and with both short and long inter-frame delays. Use of intensification and longer inter-frame delay generally improved precision. Overall, the Photron FASTCAM SA-X2 exhibited the best performance in terms of greatest precision and highest signal-to-noise ratio primarily because it had the largest pixels.

  15. Precision of FLEET Velocimetry Using High-speed CMOS Camera Systems

    NASA Technical Reports Server (NTRS)

    Peters, Christopher J.; Danehy, Paul M.; Bathel, Brett F.; Jiang, Naibo; Calvert, Nathan D.; Miles, Richard B.

    2015-01-01

    Femtosecond laser electronic excitation tagging (FLEET) is an optical measurement technique that permits quantitative velocimetry of unseeded air or nitrogen using a single laser and a single camera. In this paper, we seek to determine the fundamental precision of the FLEET technique using high-speed complementary metal-oxide semiconductor (CMOS) cameras. Also, we compare the performance of several different high-speed CMOS camera systems for acquiring FLEET velocimetry data in air and nitrogen free-jet flows. The precision was defined as the standard deviation of a set of several hundred single-shot velocity measurements. Methods of enhancing the precision of the measurement were explored such as digital binning (similar in concept to on-sensor binning, but done in post-processing), row-wise digital binning of the signal in adjacent pixels and increasing the time delay between successive exposures. These techniques generally improved precision; however, binning provided the greatest improvement to the un-intensified camera systems which had low signal-to-noise ratio. When binning row-wise by 8 pixels (about the thickness of the tagged region) and using an inter-frame delay of 65 micro sec, precisions of 0.5 m/s in air and 0.2 m/s in nitrogen were achieved. The camera comparison included a pco.dimax HD, a LaVision Imager scientific CMOS (sCMOS) and a Photron FASTCAM SA-X2, along with a two-stage LaVision High Speed IRO intensifier. Excluding the LaVision Imager sCMOS, the cameras were tested with and without intensification and with both short and long inter-frame delays. Use of intensification and longer inter-frame delay generally improved precision. Overall, the Photron FASTCAM SA-X2 exhibited the best performance in terms of greatest precision and highest signal-to-noise ratio primarily because it had the largest pixels.

  16. Research on high precision centering assembly method of roll edge optical elements

    NASA Astrophysics Data System (ADS)

    Liu, Hua; Liu, Xiaomei

    2015-08-01

    In order to improve the imaging quality of target imaging optical system, in the special environment of large temperature difference, the centering assembly precision of roll edge optical elements was studied. According to the hole-axis coordinate error theory of mechanics, by analyzing the factors affected the precision of mechanical heating surface, combining with the existing method to eliminate error and centering assembly process, a new kind of high precision centering assembly method was put forward. Using additional grinding device to grinding roll edge of optical element, eliminate the machining error on the surface of the mechanical hot working, thus improve the centering assembly precision between the roll edge optical element and lens tube. The result of experiment shows that the centering precision can reach less than 3μm when assembled optical element after roll edge using new centering assembly method, and improved by 25% compared to the traditional method of roll edge optical elements are assembled directly after hot working. New assembly method with additional grinding device can improve the centering assembly precision of roll edge optical elements, and greatly reduce the difficulty of optical design of such optical imaging system using in large temperature difference environment, when meet the same image quality.

  17. High precision measurement of the proton charge radius: The PRad experiment

    SciTech Connect

    Meziane, Mehdi

    2013-11-01

    The recent high precision measurements of the proton charge radius performed at PSI from muonic hydrogen Lamb shift puzzled the hadronic physics community. A value of 0.8418 {+-} 0.0007 fm was extracted which is 7{sigma} smaller than the previous determinations obtained from electron-proton scattering experiments and based on precision spectroscopy of electronic hydrogen. An additional extraction of the proton charge radius from electron scattering at Mainz is also in good agreement with these "electronic" determinations. An independent measurement of the proton charge radius from unpolarized elastic ep scattering using a magnetic spectrometer free method was proposed and fully approved at Jefferson Laboratory in June 2012. This novel technique uses the high precision calorimeter HyCal and a windowless hydrogen gas target which makes possible the extraction of the charge radius at very forward angles and thus very low momentum transfer Q{sup 2} up to 10{sup -4} (GeV/c){sup 2} with an unprecedented sub-percent precision for this type of experiment. In this paper, after a review of the recent progress on the proton charge radius extraction and the new high precision experiment PRad will be presented.

  18. High precision measurement of the proton charge radius: The PRad experiment

    SciTech Connect

    Meziane, Mehdi; Collaboration: PRad Collaboration

    2013-11-07

    The recent high precision measurements of the proton charge radius performed at PSI from muonic hydrogen Lamb shift puzzled the hadronic physics community. A value of 0.8418 ± 0.0007 fm was extracted which is 7σ smaller than the previous determinations obtained from electron-proton scattering experiments and based on precision spectroscopy of electronic hydrogen. An additional extraction of the proton charge radius from electron scattering at Mainz is also in good agreement with these 'electronic' determinations. An independent measurement of the proton charge radius from unpolarized elastic ep scattering using a magnetic spectrometer free method was proposed and fully approved at Jefferson Laboratory in June 2012. This novel technique uses the high precision calorimeter HyCal and a windowless hydrogen gas target which makes possible the extraction of the charge radius at very forward angles and thus very low momentum transfer Q{sup 2} up to 10{sup −4} (GeV/c){sup 2} with an unprecedented sub-percent precision for this type of experiment. In this paper, after a review of the recent progress on the proton charge radius extraction and the new high precision experiment PRad will be presented.

  19. 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.

  20. Diamond turning of high-precision roll-to-roll imprinting molds for fabricating subwavelength gratings

    NASA Astrophysics Data System (ADS)

    Liu, Chun-Wei; Yan, Jiwang; Lin, Shih-Chieh

    2016-06-01

    Diamond turning of high-precision molds is a vital process for the roll-to-roll-based ultraviolet resin imprinting process in fabricating subwavelength gratings. The effects of the grating shape and grating period on diffraction efficiencies and diffraction angles were simulated. Experiments were then conducted to examine the effects of shape design, grating period, and cutting speed on machinability of the mold. According to the optical measurement results, the performance of the subwavelength gratings matched the design well at various incident angles. The results confirm that diamond turning of high-precision molds is a feasible approach for ensuring the continual mass production of subwavelength gratings.

  1. High-precision frequency measurements in the THz spectral region using an unstabilized femtosecond laser

    NASA Astrophysics Data System (ADS)

    Füser, Heiko; Judaschke, Rolf; Bieler, Mark

    2011-09-01

    We perform high-precision frequency measurements in the THz frequency range using an unstabilized femtosecond laser. A simple and flexible algorithm is used to correct the beating signal resulting from the THz source and one comb line of the rectified optical comb for fluctuations of the laser repetition rate. Using this technique, we demonstrate an accuracy of our measurement device as high as (9 ± 3) . 10-14 for the measurement of a 100 GHz source. This is two orders of magnitude better than previous precision measurements in this frequency range employing femtosecond lasers.

  2. High-precision covariant one-boson-exchange potentials for np scattering below 350 MeV

    SciTech Connect

    Franz Gross; Alfred Stadler

    2007-12-01

    All realistic potential models for the two-nucleon interaction are to some extent based on boson exchange. However, in order to achieve an essentially perfect fit to the scattering data, characterized by a chi2/Ndata~ 1, previous potentials have abandoned a pure one boson-exchange mechanism (OBE). Using a covariant theory, we have found a true OBE potential that fits the 2006 world np data below 350 MeV with a chi2/Ndata = 1.00 for 3612 data. Our potential has fewer adjustable parameters than previous high precision potentials, and also reproduces the experimental triton binding energy without introducing additional irreducible three-nucleon forces.

  3. Technical Note: Millimeter precision in ultrasound based patient positioning: Experimental quantification of inherent technical limitations

    SciTech Connect

    Ballhausen, Hendrik Hieber, Sheila; Li, Minglun; Belka, Claus; Reiner, Michael

    2014-08-15

    Purpose: To identify the relevant technical sources of error of a system based on three-dimensional ultrasound (3D US) for patient positioning in external beam radiotherapy. To quantify these sources of error in a controlled laboratory setting. To estimate the resulting end-to-end geometric precision of the intramodality protocol. Methods: Two identical free-hand 3D US systems at both the planning-CT and the treatment room were calibrated to the laboratory frame of reference. Every step of the calibration chain was repeated multiple times to estimate its contribution to overall systematic and random error. Optimal margins were computed given the identified and quantified systematic and random errors. Results: In descending order of magnitude, the identified and quantified sources of error were: alignment of calibration phantom to laser marks 0.78 mm, alignment of lasers in treatment vs planning room 0.51 mm, calibration and tracking of 3D US probe 0.49 mm, alignment of stereoscopic infrared camera to calibration phantom 0.03 mm. Under ideal laboratory conditions, these errors are expected to limit ultrasound-based positioning to an accuracy of 1.05 mm radially. Conclusions: The investigated 3D ultrasound system achieves an intramodal accuracy of about 1 mm radially in a controlled laboratory setting. The identified systematic and random errors require an optimal clinical tumor volume to planning target volume margin of about 3 mm. These inherent technical limitations do not prevent clinical use, including hypofractionation or stereotactic body radiation therapy.

  4. Capability study for ozone high-precision retrieval with JEM/SMILES

    NASA Astrophysics Data System (ADS)

    Takahashi, Chikako; Suzuki, Makoto; Ochiai, Satoshi; Takayanagi, Masahiro

    One of the most unique characteristics of JEM/SMILES observation is its high sensitivity (500K system noise by employing 4K cooled SIS mixer) in detecting atmospheric limb emission in the submillimeter wave range, which are band A (624.3-625.5 GHz), band B (625.1-626.3 GHz), and band C (649.1-650.3 GHz). It observes limb emission from atmospheric minor constituents in the stratosphere, such as O3 , ClO, HCl, HNO3 , HOCl, CH3 CN, HO2 , BrO, O3 isotopes etc. The JEM/SMILES mission is mainly devoted to studying precise halogen chemistry related to ozone destruction. Spatial coverage is near global, that is the nominal latitude coverage is 38S - 65N owing to tilting the antenna beam to 45 degree left from the direction of orbital motion. It is highly expected that SMILES observation path encounters the atmosphere in the elongated polar voltex toward lower latitude in the northern hemisphere. The sensitivity of SMILES can be utilized for its unique observations, one is the detection of trace species which has never been observed in acceptable precision, and the other is high precision observation of major species such as O3 and HCl. This paper discusses how the ozone high-precision retrieval with the JEM/SMILES can be achieved based on the operational retrieval algorithm. The JEM/SMILES observes ozone absorption line at 625.37GHz in lower observation bands, band A and band B. As the JEM/SMILES is a high sensitive sensor, the high-precision retrieval is expected, the minimum precision of retrieved ozone height profile is 0.5% at about 30km under ideal condition, which is better than existing similar sensors, such as Aura/MLS and Odin/SMR. It is also discussed height resolutions (3.5-4.1 km nominally determined by the instrument) as trade off with precision. Thus these two factors should be decided by a kind of trade-off considering scientific requirements. The information content is used to optimize these factors and we clarify the precision, the height resolution, and

  5. Accuracy and Precision of Three-Dimensional Low Dose CT Compared to Standard RSA in Acetabular Cups: An Experimental Study

    PubMed Central

    Olivecrona, Henrik; Maguire, Gerald Q.; Noz, Marilyn E.; Zeleznik, Michael P.

    2016-01-01

    Background and Purpose. The gold standard for detection of implant wear and migration is currently radiostereometry (RSA). The purpose of this study is to compare a three-dimensional computed tomography technique (3D CT) to standard RSA as an alternative technique for measuring migration of acetabular cups in total hip arthroplasty. Materials and Methods. With tantalum beads, we marked one cemented and one uncemented cup and mounted these on a similarly marked pelvic model. A comparison was made between 3D CT and standard RSA for measuring migration. Twelve repeated stereoradiographs and CT scans with double examinations in each position and gradual migration of the implants were made. Precision and accuracy of the 3D CT were calculated. Results. The accuracy of the 3D CT ranged between 0.07 and 0.32 mm for translations and 0.21 and 0.82° for rotation. The precision ranged between 0.01 and 0.09 mm for translations and 0.06 and 0.29° for rotations, respectively. For standard RSA, the precision ranged between 0.04 and 0.09 mm for translations and 0.08 and 0.32° for rotations, respectively. There was no significant difference in precision between 3D CT and standard RSA. The effective radiation dose of the 3D CT method, comparable to RSA, was estimated to be 0.33 mSv. Interpretation. Low dose 3D CT is a comparable method to standard RSA in an experimental setting. PMID:27478832

  6. Accuracy and Precision of Three-Dimensional Low Dose CT Compared to Standard RSA in Acetabular Cups: An Experimental Study.

    PubMed

    Brodén, Cyrus; Olivecrona, Henrik; Maguire, Gerald Q; Noz, Marilyn E; Zeleznik, Michael P; Sköldenberg, Olof

    2016-01-01

    Background and Purpose. The gold standard for detection of implant wear and migration is currently radiostereometry (RSA). The purpose of this study is to compare a three-dimensional computed tomography technique (3D CT) to standard RSA as an alternative technique for measuring migration of acetabular cups in total hip arthroplasty. Materials and Methods. With tantalum beads, we marked one cemented and one uncemented cup and mounted these on a similarly marked pelvic model. A comparison was made between 3D CT and standard RSA for measuring migration. Twelve repeated stereoradiographs and CT scans with double examinations in each position and gradual migration of the implants were made. Precision and accuracy of the 3D CT were calculated. Results. The accuracy of the 3D CT ranged between 0.07 and 0.32 mm for translations and 0.21 and 0.82° for rotation. The precision ranged between 0.01 and 0.09 mm for translations and 0.06 and 0.29° for rotations, respectively. For standard RSA, the precision ranged between 0.04 and 0.09 mm for translations and 0.08 and 0.32° for rotations, respectively. There was no significant difference in precision between 3D CT and standard RSA. The effective radiation dose of the 3D CT method, comparable to RSA, was estimated to be 0.33 mSv. Interpretation. Low dose 3D CT is a comparable method to standard RSA in an experimental setting. PMID:27478832

  7. High precision position control of voice coil motor based on single neuron PID

    NASA Astrophysics Data System (ADS)

    Li, Liyi; Chen, Qiming; Tan, Guangjun; Zhu, He

    2013-01-01

    Voice coil motor(VCM) is widely used in high-speed and high-precision positioning control system in recent years. However, there are system uncertainty, nonlinear, modeling error, and external disturbances in the high-precision positioning control system, traditional PID control method is difficult to achieve precise positioning control. In this paper, a new position control strategy with a single neuron controller which has the capability of self-studying and self-adapting composed with PID controller is put forward, and the feedforward compensator is added to improve the dynamic response of the system in the position loop. Moreover, the disturbance observer is designed to suppress model parameter uncertainty and external disturbance signal in the current loop. In addition, the problem of high precision position control of VCM under the influence of significant disturbances is addressed, which including the gas-lubricated damping, the spring, the back EMF and ripple forces, on the basis, the mathematical model of VCM is established accurately. The simulation results show that this kind of controller can improve the dynamic characteristic and strengthen the robustness of the system, and the current loop with disturbance observer can also restrain disturbance and high frequency.

  8. Peculiarities of high-overtone transition probabilities in carbon monoxide revealed by high-precision calculation

    NASA Astrophysics Data System (ADS)

    Medvedev, Emile S.; Meshkov, Vladimir V.; Stolyarov, Andrey V.; Gordon, Iouli E.

    2015-10-01

    In the recent work devoted to the calculation of the rovibrational line list of the CO molecule [G. Li et al., Astrophys. J., Suppl. Ser. 216, 15 (2015)], rigorous validation of the calculated parameters including intensities was carried out. In particular, the Normal Intensity Distribution Law (NIDL) [E. S. Medvedev, J. Chem. Phys. 137, 174307 (2012)] was employed for the validation purposes, and it was found that, in the original CO line list calculated for large changes of the vibrational quantum number up to Δn = 41, intensities with Δn > 11 were unphysical. Therefore, very high overtone transitions were removed from the published list in Li et al. Here, we show how this type of validation is carried out and prove that the quadruple precision is indispensably required to predict the reliable intensities using the conventional 32-bit computers. Based on these calculations, the NIDL is shown to hold up for the 0 → n transitions till the dissociation limit around n = 83, covering 45 orders of magnitude in the intensity. The low-intensity 0 → n transition predicted in the work of Medvedev [Determination of a new molecular constant for diatomic systems. Normal intensity distribution law for overtone spectra of diatomic and polyatomic molecules and anomalies in overtone absorption spectra of diatomic molecules, Institute of Chemical Physics, Russian Academy of Sciences, Chernogolovka, 1984] at n = 5 is confirmed, and two additional "abnormal" intensities are found at n = 14 and 23. Criteria for the appearance of such "anomalies" are formulated. The results could be useful to revise the high-overtone molecular transition probabilities provided in spectroscopic databases.

  9. Peculiarities of high-overtone transition probabilities in carbon monoxide revealed by high-precision calculation

    SciTech Connect

    Medvedev, Emile S.; Meshkov, Vladimir V.; Stolyarov, Andrey V.

    2015-10-21

    In the recent work devoted to the calculation of the rovibrational line list of the CO molecule [G. Li et al., Astrophys. J., Suppl. Ser. 216, 15 (2015)], rigorous validation of the calculated parameters including intensities was carried out. In particular, the Normal Intensity Distribution Law (NIDL) [E. S. Medvedev, J. Chem. Phys. 137, 174307 (2012)] was employed for the validation purposes, and it was found that, in the original CO line list calculated for large changes of the vibrational quantum number up to Δn = 41, intensities with Δn > 11 were unphysical. Therefore, very high overtone transitions were removed from the published list in Li et al. Here, we show how this type of validation is carried out and prove that the quadruple precision is indispensably required to predict the reliable intensities using the conventional 32-bit computers. Based on these calculations, the NIDL is shown to hold up for the 0 → n transitions till the dissociation limit around n = 83, covering 45 orders of magnitude in the intensity. The low-intensity 0 → n transition predicted in the work of Medvedev [Determination of a new molecular constant for diatomic systems. Normal intensity distribution law for overtone spectra of diatomic and polyatomic molecules and anomalies in overtone absorption spectra of diatomic molecules, Institute of Chemical Physics, Russian Academy of Sciences, Chernogolovka, 1984] at n = 5 is confirmed, and two additional “abnormal” intensities are found at n = 14 and 23. Criteria for the appearance of such “anomalies” are formulated. The results could be useful to revise the high-overtone molecular transition probabilities provided in spectroscopic databases.

  10. High precision semiautomated computed tomography measurement of lumbar disk and vertebral heights

    PubMed Central

    Tan, Sovira; Yao, Jianhua; Yao, Lawrence; Ward, Michael M.

    2013-01-01

    Purpose: Evaluation of treatments of many spine disorders requires precise measurement of the heights of vertebral bodies and disk spaces. The authors present a semiautomated computer algorithm measuring those heights from spine computed tomography (CT) scans and evaluate its precision. Methods: Eight patients underwent two spine CT scans in the same day. In each scan, five thoracolumbar vertebral heights and four disk heights were estimated using the algorithm. To assess precision, the authors computed the differences between the height measurements in the two scans, coefficients of variation (CV), and 95% limits of agreement. Intraoperator and interoperator precisions were evaluated. For local vertebral and disk height measurement (anterior, middle, posterior) the algorithm was compared to a manual mid-sagittal plane method. Results: The mean (standard deviation) interscan difference was as low as 0.043 (0.031) mm for disk heights and 0.044 (0.043) mm for vertebral heights. The corresponding 95% limits of agreement were [−0.085, 0.11] and [−0.10, 0.12] mm, respectively. Intraoperator and interoperator precision was high, with a maximal CV of 0.30%. For local vertebral and disk heights, the algorithm improved upon the precision of the manual mid-sagittal plane measurement by as much as a factor of 6 and 4, respectively. Conclusions: The authors evaluated the precision of a novel computer algorithm for measuring vertebral body heights and disk heights using short term repeat CT scans of patients. The 95% limits of agreement indicate that the algorithm can detect small height changes of the order of 0.1 mm. PMID:23298096

  11. Status and outlook of CHIP-TRAP: The Central Michigan University high precision Penning trap

    NASA Astrophysics Data System (ADS)

    Redshaw, M.; Bryce, R. A.; Hawks, P.; Gamage, N. D.; Hunt, C.; Kandegedara, R. M. E. B.; Ratnayake, I. S.; Sharp, L.

    2016-06-01

    At Central Michigan University we are developing a high-precision Penning trap mass spectrometer (CHIP-TRAP) that will focus on measurements with long-lived radioactive isotopes. CHIP-TRAP will consist of a pair of hyperbolic precision-measurement Penning traps, and a cylindrical capture/filter trap in a 12 T magnetic field. Ions will be produced by external ion sources, including a laser ablation source, and transported to the capture trap at low energies enabling ions of a given m / q ratio to be selected via their time-of-flight. In the capture trap, contaminant ions will be removed with a mass-selective rf dipole excitation and the ion of interest will be transported to the measurement traps. A phase-sensitive image charge detection technique will be used for simultaneous cyclotron frequency measurements on single ions in the two precision traps, resulting in a reduction in statistical uncertainty due to magnetic field fluctuations.

  12. High precision measurements of the diamond Hugoniot in and above the melt region

    SciTech Connect

    Hicks, D; Boehly, T; Celliers, P; Bradley, D; Eggert, J; McWilliams, R S; Collins, G

    2008-08-05

    High precision laser-driven shock wave measurements of the diamond principal Hugoniot have been made at pressures between 6 and 19 Mbar. Shock velocities were determined with 0.3-1.1% precision using a velocity interferometer. Impedance matching analysis, incorporating systematic errors in the equation-of-state of the quartz standard, was used to determine the Hugoniot with 1.2-2.7% precision in density. The results are in good agreement with published ab initio calculations which predict a small negative melt slope along the Hugoniot, but disagree with previous laser-driven shock wave experiments which had observed a large density increase in the melt region. In the extensive solid-liquid coexistence regime between 6 and 10 Mbar these measurements indicate that the mixed phase may be slightly more dense than would be expected from a simple interpolation between liquid and solid Hugoniots.

  13. Highly Accurate and Precise Infrared Transition Frequencies of the H_3^+ Cation

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

    Calculation of ab initio potential energy surfaces for molecules to high accuracy is only manageable for a handful of molecular systems. Among them is the simplest polyatomic molecule, the H_3^+ cation. In order to achieve a high degree of accuracy (<1 wn) corrections must be made to the to the traditional Born-Oppenheimer approximation that take into account not only adiabatic and non-adiabatic couplings, but quantum electrodynamic corrections as well. For the lowest rovibrational levels the agreement between theory and experiment is approaching 0.001 wn, whereas the agreement is on the order of 0.01 - 0.1 wn for higher levels which are closely rivaling the uncertainties on the experimental data. As method development for calculating these various corrections progresses it becomes necessary for the uncertainties on the experimental data to be improved in order to properly benchmark the calculations. Previously we have measured 20 rovibrational transitions of H_3^+ with MHz-level precision, all of which have arisen from low lying rotational levels. Here we present new measurements of rovibrational transitions arising from higher rotational and vibrational levels. These transitions not only allow for probing higher energies on the potential energy surface, but through the use of combination differences, will ultimately lead to prediction of the "forbidden" rotational transitions with MHz-level accuracy. L.G. Diniz, J.R. Mohallem, A. Alijah, M. Pavanello, L. Adamowicz, O.L. Polyansky, J. Tennyson Phys. Rev. A (2013), 88, 032506 O.L. Polyansky, A. Alijah, N.F. Zobov, I.I. Mizus, R.I. Ovsyannikov, J. Tennyson, L. Lodi, T. Szidarovszky, A.G. Császár Phil. Trans. R. Soc. A (2012), 370, 5014 J.N. Hodges, A.J. Perry, P.A. Jenkins II, B.M. Siller, B.J. McCall J. Chem. Phys. (2013), 139, 164201 A.J. Perry, J.N. Hodges, C.R. Markus, G.S. Kocheril, B.J. McCall J. Molec. Spectrosc. (2015), 317, 71-73.

  14. High-Precision Microwave Spectroscopy of Muonium for Determination of Muonic Magnetic Moment

    NASA Astrophysics Data System (ADS)

    Torii, H. A.; Higashi, Y.; Higuchi, T.; Matsuda, Y.; Mizutani, T.; Tajima, M.; Tanaka, K. S.; Ueno, Y.; Fukao, Y.; Iinuma, H.; Ikedo, Y.; Kadono, R.; Kawamura, N.; Koda, A.; Kojima, K. M.; Mibe, T.; Miyake, Y.; Nagamine, K.; Nishiyama, K.; Ogitsu, T.; Okubo, R.; Saito, N.; Sasaki, K.; Shimomura, K.; Strasser, P.; Sugano, M.; Toyoda, A.; Ueno, K.; Yamamoto, A.; Yoshida, M.; Ishida, K.; Iwasaki, M.; Kamigaito, O.; Tomono, D.; Kanda, S.; Kubo, K.; Aoki, M.; Torikai, E.; Kawall, D.

    2016-02-01

    The muonium atom is a system suitable for precision measurements for determination of muon’s fundamental properties as well as for the test of quantum electrodynamics (QED). A microwave spectroscopy experiment of this exotic atom is being prepared at J-PARC, jointly operated by KEK and JAEA in Japan, aiming at an improved relative precision at a level of 10-8 in determination of the muonic magnetic moment. A major improvement of statistical uncertainty is expected with the higher muon intensity of the pulsed beam at J-PARC, while reduction of various sources of systematic uncertainties are being studied: those arising from microwave power fluctuations, magnetic field inhomogeneity, muon stopping distribution and atomic collisional shift of resonance frequencies. Experimental strategy and methods are presented in this paper, with an emphasis on our recent development of apparatuses and evaluation of systematic uncertainties.

  15. 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.

  16. Electromagnetic Controlled Cortical Impact Device for Precise, Graded Experimental Traumatic Brain Injury

    PubMed Central

    BRODY, DAVID L.; DONALD, CHRISTINE Mac; KESSENS, CHAD C.; YUEDE, CARLA; PARSADANIAN, MAIA; SPINNER, MIKE; KIM, EDDIE; SCHWETYE, KATHERINE E.; HOLTZMAN, DAVID M.; BAYLY, PHILIP V.

    2008-01-01

    Genetically modified mice represent useful tools for traumatic brain injury (TBI) research and attractive preclinical models for the development of novel therapeutics. Experimental methods that minimize the number of mice needed may increase the pace of discovery. With this in mind, we developed and characterized a prototype electromagnetic (EM) controlled cortical impact device along with refined surgical and behavioral testing techniques. By varying the depth of impact between 1.0 and 3.0 mm, we found that the EM device was capable of producing a broad range of injury severities. Histologically, 2.0-mm impact depth injuries produced by the EM device were similar to 1.0-mm impact depth injuries produced by a commercially available pneumatic device. Behaviorally, 2.0-, 2.5-, and 3.0-mm impacts impaired hidden platform and probe trial water maze performance, whereas 1.5-mm impacts did not. Rotorod and visible platform water maze deficits were also found following 2.5- and 3.0-mm impacts. No impairment of conditioned fear performance was detected. No differences were found between sexes of mice. Inter-operator reliability was very good. Behaviorally, we found that we could statistically distinguish between injury depths differing by 0.5 mm using 12 mice per group and between injury depths differing by 1.0 mm with 7-8 mice per group. Thus, the EM impactor and refined surgical and behavioral testing techniques may offer a reliable and convenient framework for preclinical TBI research involving mice. PMID:17439349

  17. Electromagnetic controlled cortical impact device for precise, graded experimental traumatic brain injury.

    PubMed

    Brody, David L; Mac Donald, Christine; Kessens, Chad C; Yuede, Carla; Parsadanian, Maia; Spinner, Mike; Kim, Eddie; Schwetye, Katherine E; Holtzman, David M; Bayly, Philip V

    2007-04-01

    Genetically modified mice represent useful tools for traumatic brain injury (TBI) research and attractive preclinical models for the development of novel therapeutics. Experimental methods that minimize the number of mice needed may increase the pace of discovery. With this in mind, we developed and characterized a prototype electromagnetic (EM) controlled cortical impact device along with refined surgical and behavioral testing techniques. By varying the depth of impact between 1.0 and 3.0 mm, we found that the EM device was capable of producing a broad range of injury severities. Histologically, 2.0-mm impact depth injuries produced by the EM device were similar to 1.0-mm impact depth injuries produced by a commercially available pneumatic device. Behaviorally, 2.0-, 2.5-, and 3.0-mm impacts impaired hidden platform and probe trial water maze performance, whereas 1.5-mm impacts did not. Rotorod and visible platform water maze deficits were also found following 2.5- and 3.0-mm impacts. No impairment of conditioned fear performance was detected. No differences were found between sexes of mice. Inter-operator reliability was very good. Behaviorally, we found that we could statistically distinguish between injury depths differing by 0.5 mm using 12 mice per group and between injury depths differing by 1.0 mm with 7-8 mice per group. Thus, the EM impactor and refined surgical and behavioral testing techniques may offer a reliable and convenient framework for preclinical TBI research involving mice.

  18. Experimental and theoretical investigation of the precise transduction mechanism in giant magnetoresistive biosensors.

    PubMed

    Lee, Jung-Rok; Sato, Noriyuki; Bechstein, Daniel J B; Osterfeld, Sebastian J; Wang, Junyi; Gani, Adi Wijaya; Hall, Drew A; Wang, Shan X

    2016-01-05

    Giant magnetoresistive (GMR) biosensors consisting of many rectangular stripes are being developed for high sensitivity medical diagnostics of diseases at early stages, but many aspects of the sensing mechanism remain to be clarified. Using e-beam patterned masks on the sensors, we showed that the magnetic nanoparticles with a diameter of 50 nm located between the stripes predominantly determine the sensor signals over those located on the sensor stripes. Based on computational analysis, it was confirmed that the particles in the trench, particularly those near the edges of the stripes, mainly affect the sensor signals due to additional field from the stripe under an applied field. We also demonstrated that the direction of the average magnetic field from the particles that contributes to the signal is indeed the same as that of the applied field, indicating that the particles in the trench are pivotal to produce sensor signal. Importantly, the same detection principle was validated with a duplex protein assay. Also, 8 different types of sensor stripes were fabricated and design parameters were explored. According to the detection principle uncovered, GMR biosensors can be further optimized to improve their sensitivity, which is highly desirable for early diagnosis of diseases.

  19. Experimental and theoretical investigation of the precise transduction mechanism in giant magnetoresistive biosensors

    NASA Astrophysics Data System (ADS)

    Lee, Jung-Rok; Sato, Noriyuki; Bechstein, Daniel J. B.; Osterfeld, Sebastian J.; Wang, Junyi; Gani, Adi Wijaya; Hall, Drew A.; Wang, Shan X.

    2016-01-01

    Giant magnetoresistive (GMR) biosensors consisting of many rectangular stripes are being developed for high sensitivity medical diagnostics of diseases at early stages, but many aspects of the sensing mechanism remain to be clarified. Using e-beam patterned masks on the sensors, we showed that the magnetic nanoparticles with a diameter of 50 nm located between the stripes predominantly determine the sensor signals over those located on the sensor stripes. Based on computational analysis, it was confirmed that the particles in the trench, particularly those near the edges of the stripes, mainly affect the sensor signals due to additional field from the stripe under an applied field. We also demonstrated that the direction of the average magnetic field from the particles that contributes to the signal is indeed the same as that of the applied field, indicating that the particles in the trench are pivotal to produce sensor signal. Importantly, the same detection principle was validated with a duplex protein assay. Also, 8 different types of sensor stripes were fabricated and design parameters were explored. According to the detection principle uncovered, GMR biosensors can be further optimized to improve their sensitivity, which is highly desirable for early diagnosis of diseases.

  20. Experimental and theoretical investigation of the precise transduction mechanism in giant magnetoresistive biosensors

    PubMed Central

    Lee, Jung-Rok; Sato, Noriyuki; Bechstein, Daniel J. B.; Osterfeld, Sebastian J.; Wang, Junyi; Gani, Adi Wijaya; Hall, Drew A.; Wang, Shan X.

    2016-01-01

    Giant magnetoresistive (GMR) biosensors consisting of many rectangular stripes are being developed for high sensitivity medical diagnostics of diseases at early stages, but many aspects of the sensing mechanism remain to be clarified. Using e-beam patterned masks on the sensors, we showed that the magnetic nanoparticles with a diameter of 50 nm located between the stripes predominantly determine the sensor signals over those located on the sensor stripes. Based on computational analysis, it was confirmed that the particles in the trench, particularly those near the edges of the stripes, mainly affect the sensor signals due to additional field from the stripe under an applied field. We also demonstrated that the direction of the average magnetic field from the particles that contributes to the signal is indeed the same as that of the applied field, indicating that the particles in the trench are pivotal to produce sensor signal. Importantly, the same detection principle was validated with a duplex protein assay. Also, 8 different types of sensor stripes were fabricated and design parameters were explored. According to the detection principle uncovered, GMR biosensors can be further optimized to improve their sensitivity, which is highly desirable for early diagnosis of diseases. PMID:26728870

  1. Development and simulation of microfluidic Wheatstone bridge for high-precision sensor

    NASA Astrophysics Data System (ADS)

    Shipulya, N. D.; Konakov, S. A.; VKrzhizhanovskaya, V.

    2016-08-01

    In this work we present the results of analytical modeling and 3D computer simulation of microfluidic Wheatstone bridge, which is used for high-accuracy measurements and precision instruments. We propose and simulate a new method of a bridge balancing process by changing the microchannel geometry. This process is based on the “etching in microchannel” technology we developed earlier (doi:10.1088/1742-6596/681/1/012035). Our method ensures a precise control of the flow rate and flow direction in the bridge microchannel. The advantage of our approach is the ability to work without any control valves and other active electronic systems, which are usually used for bridge balancing. The geometrical configuration of microchannels was selected based on the analytical estimations. A detailed 3D numerical model was based on Navier-Stokes equations for a laminar fluid flow at low Reynolds numbers. We investigated the behavior of the Wheatstone bridge under different process conditions; found a relation between the channel resistance and flow rate through the bridge; and calculated the pressure drop across the system under different total flow rates and viscosities. Finally, we describe a high-precision microfluidic pressure sensor that employs the Wheatstone bridge and discuss other applications in complex precision microfluidic systems.

  2. Experimental study of the fabrication of chalcogenide glass lenses by using precision glass molding

    NASA Astrophysics Data System (ADS)

    Cha, Du Hwan; Kim, Jeong-Ho; Kim, Hye-Jeong

    2014-11-01

    Although the development of small formats (640 × 480 pixel arrays) and amorphous silicon microbolometers has greatly decreased detector cost, another important component of a thermal camera, the optics, still prohibit a breakthrough for high-volume commercial systems. The aspheric lenses used in thermal imaging are typically made using the costly single-point diamond turning (SPDT) process with expensive single-crystal materials (Ge, ZnS, etc.). As a potential solution to reduce cost, the compression molding method using chalcogenide glass has become attractive for fabricating IR optics. The present paper reports the fabrication of a mold and a molded chalcogenide glass lens for a thermal security camera. In addition, the molded chalcogenide glass lens was evaluated using the form error, roughness and decentration for each surface of the molded lens. From the evaluation results, we verified that the molded lens was capable of being used for thermal imaging applications.

  3. Geological effect of high-precise gravimetric and magnetic surveys in Yangqiao prospect in Biyang depression

    SciTech Connect

    Rongyuan, W.; Zhaoling, Y.; Zhangmin, G.; Xiaoliu, W. )

    1991-01-01

    This paper reports on Yangqiao prospect in Biyang depression which is an area where very high-degree exploration has been done. The complicated seismic and geological conditions in the border area of the depression cause very poor seismic data, so that exact structural configuration can not be known. Thus, high-precise gravimetric-magnetic surveys were done. The interpretations of gravimetric and magnetic data are mainly based on the properties of gravitational and magnetic fields. Local gravimetric and magnetic anomalies at Wangzhuang were discovered by performing forward fitting of observed gravimetric and magnetic data. The repeated seismic interpretation by reference to the gravimetric-magnetic interpretation result confirms the existence of an anticline structure in the local gravimetric and magnetic anomaly area. The effect of direct hydrocarbon prediction using high- precise gravimetric and magnetic data were checked in known Anpeng and Xiaermen oil fields. The check shows good effect.

  4. 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.

  5. High precision titanium isotope measurements on geological samples by high resolution MC-ICPMS

    NASA Astrophysics Data System (ADS)

    Leya, Ingo; Schönbächler, Maria; Wiechert, Uwe; Krähenbühl, Urs; Halliday, Alex N.

    2007-05-01

    A method has been developed for the precise and reproducible measurement of Ti isotopes in natural materials using high resolution MC-ICPMS. Instrumental mass fractionation is internally corrected using 49Ti/47Ti. Replicate measurements of synthetic standard solutions, terrestrial rocks, and the carbonaceous chondrite Allende yield a long-term reproducibility (2[sigma]) of 0.28[var epsilon], 0.34[var epsilon], and 0.28[var epsilon] for 50Ti/47Ti, 48Ti/47Ti, and 46Ti/47Ti, respectively. Isobaric interferences from 46,48Ca+, 50V+, 50Cr+, and doubly charged Zr can be corrected for reliably in separated Ti solutions with Ca/Ti < 5, V/Ti < 0.3, Cr/Ti < 0.2, and Zr/Ti < 1, respectively. Such elemental ratios are achieved easily in most samples using the anion-exchange procedure presented. Single and double charged polyatomic ions can either be resolved, e.g., 14N36Ar+, or do not compromise the measurements. The method has been successfully applied to terrestrial rocks, meteorites, and various mineral separates. Terrestrial samples and standards agree within analytical uncertainties but are consistently different from the recommended values of Niederer et al. [F.R. Niederer, D.A. Papanastassiou, G.J. Wasserburg, Geochim. Cosmochim. Acta 45 (1981) 1017] with the largest effect on 50Ti/47Ti. The new results provide evidence that the recommended terrestrial 50Ti/47Ti is not well constrained; our data are higher by ~13[var epsilon] than the recommended value. Better agreement is found with the values recommended by Heydegger et al. [H.R. Heydegger, J.J. Foster, W. Compston, Earth Planet. Sci. Lett. 58 (1982) 406]. Our best estimate for the isotopic composition of terrestrial Ti (relative to 49Ti/47Ti = 0.749766) is: 50Ti/47Ti = 0.73010, 48Ti/47Ti = 10.06884, and 46Ti/47Ti = 1.09325. This corresponds to an atomic weight of 47.877, significantly different from the value of 47.867 recommended by IUPAC. A 50Ti/47Ti anomaly for bulk Allende of 3.37 ± 0.51[var epsilon] is found

  6. High-precision reflectometry of multilayer coatings for extreme ultraviolet lithography

    SciTech Connect

    Wedowski, M; Underwood, J H; Gullikson, E M; Bajt, S; Folta, J A; Kearney, P A; Montcalm, C; Spiller, E

    1999-12-29

    Synchrotron-based reflectometry is an important technique for the precise determination of optical properties of reflective multilayer coatings for Extreme Ultraviolet Lithography (EUVL). Multilayer coatings enable normal incidence reflectances of more than 65% in the wavelength range between 11 and 15 nm. In order to achieve high resolution and throughput of EUVL systems, stringent requirements not only apply to their mechanical and optical layout, but also apply to the optical properties of the multilayer coatings. Therefore, multilayer deposition on near-normal incidence optical surfaces of projection optics, condenser optics and reflective masks requires suitable high-precision metrology. Most important, due to their small bandpass on the order of only 0.5 nm, all reflective multilayer coatings in EUVL systems must be wavelength-matched to within {+-}0.05 nm. In some cases, a gradient of the coating thickness is necessary for wavelength matching at variable average angle of incidence in different locations on the optical surfaces. Furthermore, in order to preserve the geometrical figure of the optical substrates, reflective multilayer coatings need to be uniform to within 0.01 nm in their center wavelength. This requirement can only be fulfilled with suitable metrology, which provides a precision of a fraction of this value. In addition, for the detailed understanding and the further development of reflective multilayer coatings a precision in the determination of peak reflectances is desirable on the order of 0.1%. Substrates up to 200 mm in diameter and 15 kg in mass need to be accommodated. Above requirements are fulfilled at beamline 6.3.2 of the Advanced Light Source (ALS) in Berkeley. This beamline proved to be precise within 0.2% (ms) for reflectance and 0.002 nm (rms) for wavelength.

  7. A high-precision instrument for analyzing nonlinear dynamic behavior of bearing cage

    NASA Astrophysics Data System (ADS)

    Yang, Z.; Chen, H.; Yu, T.; Li, B.

    2016-08-01

    The high-precision ball bearing is fundamental to the performance of complex mechanical systems. As the speed increases, the cage behavior becomes a key factor in influencing the bearing performance, especially life and reliability. This paper develops a high-precision instrument for analyzing nonlinear dynamic behavior of the bearing cage. The trajectory of the rotational center and non-repetitive run-out (NRRO) of the cage are used to evaluate the instability of cage motion. This instrument applied an aerostatic spindle to support and spin test the bearing to decrease the influence of system error. Then, a high-speed camera is used to capture images when the bearing works at high speeds. A 3D trajectory tracking software tema Motion is used to track the spot which marked the cage surface. Finally, by developing the matlab program, a Lissajous' figure was used to evaluate the nonlinear dynamic behavior of the cage with different speeds. The trajectory of rotational center and NRRO of the cage with various speeds are analyzed. The results can be used to predict the initial failure and optimize cage structural parameters. In addition, the repeatability precision of instrument is also validated. In the future, the motorized spindle will be applied to increase testing speed and image processing algorithms will be developed to analyze the trajectory of the cage.

  8. A high-precision instrument for analyzing nonlinear dynamic behavior of bearing cage.

    PubMed

    Yang, Z; Chen, H; Yu, T; Li, B

    2016-08-01

    The high-precision ball bearing is fundamental to the performance of complex mechanical systems. As the speed increases, the cage behavior becomes a key factor in influencing the bearing performance, especially life and reliability. This paper develops a high-precision instrument for analyzing nonlinear dynamic behavior of the bearing cage. The trajectory of the rotational center and non-repetitive run-out (NRRO) of the cage are used to evaluate the instability of cage motion. This instrument applied an aerostatic spindle to support and spin test the bearing to decrease the influence of system error. Then, a high-speed camera is used to capture images when the bearing works at high speeds. A 3D trajectory tracking software tema Motion is used to track the spot which marked the cage surface. Finally, by developing the matlab program, a Lissajous' figure was used to evaluate the nonlinear dynamic behavior of the cage with different speeds. The trajectory of rotational center and NRRO of the cage with various speeds are analyzed. The results can be used to predict the initial failure and optimize cage structural parameters. In addition, the repeatability precision of instrument is also validated. In the future, the motorized spindle will be applied to increase testing speed and image processing algorithms will be developed to analyze the trajectory of the cage. PMID:27587158

  9. A discrete time-varying internal model-based approach for high precision tracking of a multi-axis servo gantry.

    PubMed

    Zhang, Zhen; Yan, Peng; Jiang, Huan; Ye, Peiqing

    2014-09-01

    In this paper, we consider the discrete time-varying internal model-based control design for high precision tracking of complicated reference trajectories generated by time-varying systems. Based on a novel parallel time-varying internal model structure, asymptotic tracking conditions for the design of internal model units are developed, and a low order robust time-varying stabilizer is further synthesized. In a discrete time setting, the high precision tracking control architecture is deployed on a Voice Coil Motor (VCM) actuated servo gantry system, where numerical simulations and real time experimental results are provided, achieving the tracking errors around 3.5‰ for frequency-varying signals.

  10. [Experimental and theoretical high energy physics program

    SciTech Connect

    Finley, J.; Gaidos, J.A.; Loeffler, F.J.; McIlwain, R.L.; Miller, D.H.; Palfrey, T.R.; Shibata, E.I.; Shipsey, I.P.

    1993-04-01

    Experimental and theoretical high-energy physics research at Purdue is summarized in a number of reports. Subjects treated include the following: the CLEO experiment for the study of heavy flavor physics; gas microstrip detectors; particle astrophysics; affine Kac{endash}Moody algebra; nonperturbative mass bounds on scalar and fermion systems due to triviality and vacuum stability constraints; resonance neutrino oscillations; e{sup +}e{sup {minus}} collisions at CERN; {bar p}{endash}p collisions at FNAL; accelerator physics at Fermilab; development work for the SDC detector at SSC; TOPAZ; D-zero physics; physics beyond the standard model; and the Collider Detector at Fermilab. (RWR)

  11. High-precision, automated integration of multiple isothermal titration calorimetric thermograms: new features of NITPIC

    PubMed Central

    Scheuermann, Thomas H.; Brautigam, Chad A.

    2014-01-01

    Isothermal titration calorimetry (ITC) has become a standard and widely available tool to measure the thermodynamic parameters of macromolecular associations. Modern applications of the method, including global analysis and drug screening, require the acquisition of multiple sets of data; sometimes these data sets number in the hundreds. Therefore, there is a need for quick, precise, and automated means to process the data, particularly at the first step of data analysis, which is commonly the integration of the raw data to yield an interpretable isotherm. Herein, we describe enhancements to an algorithm that previously has been shown to provide an automated, unbiased, and high-precision means to integrate ITC data. These improvements allow for the speedy and precise serial integration of an unlimited number of ITC data sets, and they have been implemented in the freeware program NITPIC, version 1.1.0. We present a comprehensive comparison of the performance of this software against an older version of NITPIC and a current version of Origin, which is commonly used for integration. The new methods recapitulate the excellent performance of the previous versions of NITPIC while speeding it up substantially, and their precision is significantly better than that of Origin. This new version of NITPIC is therefore well suited to the serial integration of many ITC data sets. PMID:25524420

  12. Direct high-precision measurement of the magnetic moment of the proton.

    PubMed

    Mooser, A; Ulmer, S; Blaum, K; Franke, K; Kracke, H; Leiteritz, C; Quint, W; Rodegheri, C C; Smorra, C; Walz, J

    2014-05-29

    One of the fundamental properties of the proton is its magnetic moment, µp. So far µp has been measured only indirectly, by analysing the spectrum of an atomic hydrogen maser in a magnetic field. Here we report the direct high-precision measurement of the magnetic moment of a single proton using the double Penning-trap technique. We drive proton-spin quantum jumps by a magnetic radio-frequency field in a Penning trap with a homogeneous magnetic field. The induced spin transitions are detected in a second trap with a strong superimposed magnetic inhomogeneity. This enables the measurement of the spin-flip probability as a function of the drive frequency. In each measurement the proton's cyclotron frequency is used to determine the magnetic field of the trap. From the normalized resonance curve, we extract the particle's magnetic moment in terms of the nuclear magneton: μp = 2.792847350(9)μN. This measurement outperforms previous Penning-trap measurements in terms of precision by a factor of about 760. It improves the precision of the forty-year-old indirect measurement, in which significant theoretical bound state corrections were required to obtain µp, by a factor of 3. By application of this method to the antiproton magnetic moment, the fractional precision of the recently reported value can be improved by a factor of at least 1,000. Combined with the present result, this will provide a stringent test of matter/antimatter symmetry with baryons.

  13. High-precision, automated integration of multiple isothermal titration calorimetric thermograms: new features of NITPIC.

    PubMed

    Scheuermann, Thomas H; Brautigam, Chad A

    2015-04-01

    Isothermal titration calorimetry (ITC) has become a standard and widely available tool to measure the thermodynamic parameters of macromolecular associations. Modern applications of the method, including global analysis and drug screening, require the acquisition of multiple sets of data; sometimes these data sets number in the hundreds. Therefore, there is a need for quick, precise, and automated means to process the data, particularly at the first step of data analysis, which is commonly the integration of the raw data to yield an interpretable isotherm. Herein, we describe enhancements to an algorithm that previously has been shown to provide an automated, unbiased, and high-precision means to integrate ITC data. These improvements allow for the speedy and precise serial integration of an unlimited number of ITC data sets, and they have been implemented in the freeware program NITPIC, version 1.1.0. We present a comprehensive comparison of the performance of this software against an older version of NITPIC and a current version of Origin, which is commonly used for integration. The new methods recapitulate the excellent performance of the previous versions of NITPIC while speeding it up substantially, and their precision is significantly better than that of Origin. This new version of NITPIC is therefore well suited to the serial integration of many ITC data sets. PMID:25524420

  14. Fast-response, high-precision carbon monoxide sensor using a tunable diode laser absorption technique

    NASA Technical Reports Server (NTRS)

    Sachse, Glen W.; Hill, Gerald F.; Wade, Larry O.; Perry, Murray G.

    1987-01-01

    A tunable diode laser instrument, denoted as DACOM (Differential Absorption CO Measurement), has been developed to meet the fast-response, high-precision CO measurement needs of the GTE (Global Tropospheric Experiment) program. Under the GTE program, DACOM participated in the three field missions of CITE 1 (Chemical Instrumentation Test and Evaluation 1), a project involving the intercomparison of trace gas measurement techniques. DACOM performance, including analyses of measurement error sources, is discussed for the ground-based mission at Wallops Island, VA (summer 1983), and two missions on the NASA CV-990 (fall 1983 and spring 1984). Examples of fast-response (about 1 s), high-precision (+ or - 1 part per billion by volume, + or - 1.5 percent of reading) airborne data are included to illustrate the capability of this instrument.

  15. Determination of the half-life of 213Fr with high precision

    NASA Astrophysics Data System (ADS)

    Fisichella, M.; Musumarra, A.; Farinon, F.; Nociforo, C.; Del Zoppo, A.; Figuera, P.; La Cognata, M.; Pellegriti, M. G.; Scuderi, V.; Torresi, D.; Strano, E.

    2013-07-01

    High-precision measurement of half-life and Qα value of neutral and highly charged α emitters is a major subject of investigation currently. In this framework, we recently pushed half-life measurements of neutral emitters to a precision of a few per mil. This result was achieved by using different techniques and apparatuses at Istituto Nazionale di Fisica Nucleare Laboratori Nazionali del Sud (INFN-LNS) and GSI Darmstadt. Here we report on 213Fr half-life determination [T1/2(213Fr) = 34.14±0.06 s] at INFN-LNS, detailing the measurement protocol used. Direct comparison with the accepted value in the literature shows a discrepancy of more than three sigma. We propose this new value as a reference, discussing previous experiments.

  16. High-precision measurement of pixel positions in a charge-coupled device.

    PubMed

    Shaklan, S; Sharman, M C; Pravdo, S H

    1995-10-10

    The high level of spatial uniformity in modern CCD's makes them excellent devices for astrometric instruments. However, at the level of accuracy envisioned by the more ambitious projects such as the Astrometric Imaging Telescope, current technology produces CCD's with significant pixel registration errors. We describe a technique for making high-precision measurements of relative pixel positions. We measured CCD's manufactured for the Wide Field Planetary Camera II installed in the Hubble Space Telescope. These CCD's are shown to have significant step-and-repeat errors of 0.033 pixel along every 34th row, as well as a 0.003-pixel curvature along 34-pixel stripes. The source of these errors is described. Our experiments achieved a per-pixel accuracy of 0.011 pixel. The ultimate shot-noise limited precision of the method is less than 0.001 pixel.

  17. VizieR Online Data Catalog: High-precision abundances for stars with planets (Ramirez+, 2014)

    NASA Astrophysics Data System (ADS)

    Ramirez, I.; Melendez, J.; Asplund, M.

    2013-11-01

    High-precision stellar parameters and chemical abundances are presented for 111 stars; 52 of them are late-F type dwarfs and 59 are metal-rich solar analogs. The atomic linelist employed in the derivation of chemical abundances is also given. This linelist includes hyperfine structure parameters for some species. The stars' isochrone masses and ages are also reported, along with estimates of chromospheric activity. (5 data files).

  18. High-precision gravity network to monitor temporal variations in gravity across Yucca Mountain, Nevada

    SciTech Connect

    Harris, R.N.; Ponce, D.A.

    1988-12-31

    Repeatable high-precision gravity surveys provide a method of monitoring temporal variations in the gravity field. Fluctuations in the gravity field may indicate water table changes, crustal deformation, or precursors to volcanism and earthquakes. This report describes a high-precision gravity loop which has been established across Yucca Mountain, Nevada in support of the Nevada Nuclear Waste Storage Investigations (NNWSI) program. The purpose of this gravity loop is to monitor temporal variations in gravity across Yucca Mountain in an effort to interpret and predict the stability of the tectonic framework and changes in the subsurface density field. Studies of the tectonic framework which include volcanic hazard seismicity, and faulting studies are in progress. Repeat high-precision gravity surveys are less expensive and can be made more rapidly than a corresponding leveling survey. High-precision gravity surveys are capable of detecting elevation changes of 3 to 5 cm, and thus can be employed as an efficient tool for monitoring vertical crustal movements while supplementing or partially replacing leveling data. The Yucca Mountain gravity network has been tied to absolute gravity measurements established in southern Nevada. These ties provide an absolute datum for comparing repeat occupations of the gravity network, and provide a method of monitoring broad-scale changes in gravity. Absolute gravity measurements were also made at the bottom and top of the Charleston Peak calibration loop in southern Nevada. These absolute gravity measurements provide local control of calibrating gravity meters over the gravity ranges observed at Yucca Mountain. 13 refs., 7 figs., 3 tabs.

  19. Ultrashort pulse Cr4+:YAG laser for high precision infrared frequency interval measurements

    PubMed Central

    Alcock, A. J.; Ma, P.; Poole, P. J.; Chepurov, S.; Czajkowski, A.; Bernard, J. E.; Madej, A. A.; Fraser, J. M.; Mitchell, I. V.; Sorokina, I. T.; Sorokin, E.

    2010-01-01

    A cavity stabilized, SESAM mode-locked Cr4+:YAG laser capable of generating sub-100 fs pulses has been developed. Locking the 130-MHz pulse repetition frequency to that of a hydrogen maser-referenced frequency synthesizer provides a 30-nm wide frequency comb for the 1530-nm wavelength region. In conjunction with a pair of acetylene stabilized, external cavity diode lasers, this laser provides a high precision measurement tool for the determination of acetylene transition frequencies. PMID:19498916

  20. A highly efficient, compact Yb:KYW laser for mobile precision systems

    SciTech Connect

    Kuznetsov, S A; Pivtsov, V S

    2014-05-30

    We have developed a promising scheme of a multimodediode-pumped ytterbium laser. The Yb:KYW laser in the cw regime demonstrates record-high differential (40%) and total optical (35%) efficiencies. Mode locking is realised, which allows the scheme to be used for the development of compact laser systems, such as mobile femtosecond precision synthesisers. The peculiarities of the laser operation and ways of further improving its efficiency are discussed. (lasers)

  1. 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.

  2. The high precision control of the satellites formation for diffraction imaging

    NASA Astrophysics Data System (ADS)

    Yang, Guang; He, Liang; Song, Ting; Sun, Binglei; Hao, Tianwei

    2016-01-01

    To satisfy need of high resolution observation from space. This article elaborates a method of high precision spacecraft formation control based on file diffraction theory. Improving the spacecraft control accuracy to millimeter is a challenge. With the method in this article this challenge can be solved. The algorithm in this article concerning the vibration of spacecraft and based on dynamic modeling of even relative quaternion theory deduced a method of attitude and orbit integrated control. Using this control algorithm to simulation can get the result that it can make the spacecraft integrate formation control as the technical basis of space high resolution observation.

  3. Accurate time delay technology in simulated test for high precision laser range finder

    NASA Astrophysics Data System (ADS)

    Chen, Zhibin; Xiao, Wenjian; Wang, Weiming; Xue, Mingxi

    2015-10-01

    With the continuous development of technology, the ranging accuracy of pulsed laser range finder (LRF) is higher and higher, so the maintenance demand of LRF is also rising. According to the dominant ideology of "time analog spatial distance" in simulated test for pulsed range finder, the key of distance simulation precision lies in the adjustable time delay. By analyzing and comparing the advantages and disadvantages of fiber and circuit delay, a method was proposed to improve the accuracy of the circuit delay without increasing the count frequency of the circuit. A high precision controllable delay circuit was designed by combining the internal delay circuit and external delay circuit which could compensate the delay error in real time. And then the circuit delay accuracy could be increased. The accuracy of the novel circuit delay methods proposed in this paper was actually measured by a high sampling rate oscilloscope actual measurement. The measurement result shows that the accuracy of the distance simulated by the circuit delay is increased from +/- 0.75m up to +/- 0.15m. The accuracy of the simulated distance is greatly improved in simulated test for high precision pulsed range finder.

  4. High precision U-PB geochronology and implications for the tectonic evolution of the Superior Province

    NASA Technical Reports Server (NTRS)

    Davis, D. W.; Corfu, F.; Krogh, T. E.

    1986-01-01

    The underlying mechanisms of Archean tectonics and the degree to which modern plate tectonic models are applicable early in Earth's history continue to be a subject of considerable debate. A precise knowledge of the timing of geological events is of the utmost importance in studying this problem. The high precision U-Pb method has been applied in recent years to rock units in many areas of the Superior Province. Most of these data have precisions of about + or - 2-3 Ma. The resulting detailed chronologies of local igneous development and the regional age relationships furnish tight constraints on any Archean tectonic model. Superior province terrains can be classified into 3 types: (1) low grade areas dominated by meta-volcanic rocks (greenstone belts); (2) high grade, largely metaplutonic areas with abundant orthogneiss and foliated to massive I-type granitoid bodies; and (3) high grade areas with abundant metasediments, paragneiss and S-type plutons. Most of the U-Pb age determinations have been done on type 1 terrains with very few having been done in type 3 terrains. A compilation of over 120 ages indicates that the major part of igneous activity took place in the period 2760-2670 Ma, known as the Kenoran event. This event was ubiquitous throughout the Superior Province.

  5. Precision of high-resolution multibeam echo sounding coupled with high-accuracy positioning in a shallow water coastal environment

    NASA Astrophysics Data System (ADS)

    Ernstsen, Verner B.; Noormets, Riko; Hebbeln, Dierk; Bartholomä, Alex; Flemming, Burg W.

    2006-09-01

    Over 4 years, repetitive bathymetric measurements of a shipwreck in the Grådyb tidal inlet channel in the Danish Wadden Sea were carried out using a state-of-the-art high-resolution multibeam echosounder (MBES) coupled with a real-time long range kinematic (LRK™) global positioning system. Seven measurements during a single survey in 2003 ( n=7) revealed a horizontal and vertical precision of the MBES system of ±20 and ±2 cm, respectively, at a 95% confidence level. By contrast, four annual surveys from 2002 to 2005 ( n=4) yielded a horizontal and vertical precision (at 95% confidence level) of only ±30 and ±8 cm, respectively. This difference in precision can be explained by three main factors: (1) the dismounting of the system between the annual surveys, (2) rougher sea conditions during the survey in 2004 and (3) the limited number of annual surveys. In general, the precision achieved here did not correspond to the full potential of the MBES system, as this could certainly have been improved by an increase in coverage density (soundings/m2), achievable by reducing the survey speed of the vessel. Nevertheless, precision was higher than that reported to date for earlier offshore test surveys using comparable equipment.

  6. High-precision iron isotope measurements of terrestrial and lunar materials

    NASA Astrophysics Data System (ADS)

    Beard, Brian L.; Johnson, Clark M.

    1999-06-01

    We present the analytical methods that have been developed for the first high-precision Fe isotope analyses that clearly identify naturally-occurring, mass-dependent isotope fractionation. A double-spike approach is used, which allows rigorous correction of instrumental mass fractionation. Based on 21 analyses of an ultra pure Fe standard, the external precision (1-SD) for measuring the isotopic composition of Fe is ±0.14 ‰/mass; for demonstrated reproducibility on samples, this precision exceeds by at least an order of magnitude that of previous attempts to empirically control instrumentally-produced mass fractionation (Dixon et al., 1993). Using the double-spike method, 15 terrestrial igneous rocks that range in composition from peridotite to rhyolite, 5 high-Ti lunar basalts, 5 Fe-Mn nodules, and a banded iron formation have been analyzed for their iron isotopic composition. The terrestrial and lunar igneous rocks have the same isotopic compositions as the ultra pure Fe standard, providing a reference Fe isotope composition for the Earth and Moon. In contrast, Fe-Mn nodules and a sample of a banded iron formation have iron isotope compositions that vary over a relatively wide range, from δ 56Fe = +0.9 to -1.2 ‰; this range is 15 times the analytical errors of our technique. These natural isotopic fractionations are interpreted to reflect biological ("vital") effects, and illustrate the great potential Fe isotope studies have for studying modern and ancient biological processes.

  7. High Precision Oxygen Three Isotope Analysis of Wild-2 Particles and Anhydrous Chondritic Interplanetary Dust Particles

    NASA Technical Reports Server (NTRS)

    Nakashima, D.; Ushikubo, T.; Zolensky, Michael E.; Weisberg, M. K.; Joswiak, D. J.; Brownlee, D. E.; Matrajt, G.; Kita, N. T.

    2011-01-01

    One of the most important discoveries from comet Wild-2 samples was observation of crystalline silicate particles that resemble chondrules and CAIs in carbonaceous chondrites. Previous oxygen isotope analyses of crystalline silicate terminal particles showed heterogeneous oxygen isotope ratios with delta(sup 18)O to approx. delta(sup 17)O down to -50% in the CAI-like particle Inti, a relict olivine grain in Gozen-sama, and an olivine particle. However, many Wild-2 particles as well as ferromagnesian silicates in anhydrous interplanetary dust particles (IDPs) showed Delta(sup 17)O values that cluster around -2%. In carbonaceous chondrites, chondrules seem to show two major isotope reservoirs with Delta(sup 17)O values at -5% and -2%. It was suggested that the Delta(sup 17)O = -2% is the common oxygen isotope reservoir for carbonaceous chondrite chondrules and cometary dust, from the outer asteroid belt to the Kuiper belt region. However, a larger dataset with high precision isotope analyses (+/-1-2%) is still needed to resolve the similarities or distinctions among Wild-2 particles, IDPs and chondrules in meteorites. We have made signifi-cant efforts to establish routine analyses of small particles (< or =10micronsm) at 1-2% precision using IMS-1280 at WiscSIMS laboratory. Here we report new results of high precision oxygen isotope analyses of Wild-2 particles and anhydrous chondritic IDPs, and discuss the relationship between the cometary dust and carbonaceous chondrite chondrules.

  8. Limiting Energy Dissipation Induces Glassy Kinetics in Single-Cell High-Precision Responses

    NASA Astrophysics Data System (ADS)

    Das, Jayajit

    2016-03-01

    Single cells often generate precise responses by involving dissipative out-of-thermodynamic equilibrium processes in signaling networks. The available free energy to fuel these processes could become limited depending on the metabolic state of an individual cell. How does limiting dissipation affect the kinetics of high precision responses in single cells? I address this question in the context of a kinetic proofreading scheme used in a simple model of early time T cell signaling. I show using exact analytical calculations and numerical simulations that limiting dissipation qualitatively changes the kinetics in single cells marked by emergence of slow kinetics, large cell-to-cell variations of copy numbers, temporally correlated stochastic events (dynamic facilitation), and, ergodicity breaking. Thus, constraints in energy dissipation, in addition to negatively affecting ligand discrimination in T cells, can create a fundamental difficulty in interpreting single cell kinetics from cell population level results.

  9. High-precision masses of neutron-deficient rubidium isotopes using a Penning trap mass spectrometer

    SciTech Connect

    Kellerbauer, A.; Audi, G.; Guenaut, C.; Lunney, D.; Beck, D.; Herfurth, F.; Kluge, H.-J.; Weber, C.; Yazidjian, C.; Blaum, K.; Bollen, G.; Schwarz, S.; Herlert, A.; Schweikhard, L.

    2007-10-15

    The atomic masses of the neutron-deficient radioactive rubidium isotopes {sup 74-77,79,80,83}Rb have been measured with the Penning trap mass spectrometer ISOLTRAP. Using the time-of-flight cyclotron resonance technique, relative mass uncertainties ranging from 1.6x10{sup -8} to 5.6x10{sup -8} were achieved. In all cases, the mass precision was significantly improved as compared with the prior Atomic-Mass Evaluation; no significant deviations from the literature values were observed. The exotic nuclide {sup 74}Rb, with a half-life of only 65 ms, is the shortest-lived nuclide on which a high-precision mass measurement in a Penning trap has been carried out. The significance of these measurements for a check of the conserved-vector-current hypothesis of the weak interaction and the unitarity of the Cabibbo-Kobayashi-Maskawa matrix is discussed.

  10. High precision Multifrequency Electrical Impedance Tomography System and Preliminary imaging results on saline tank.

    PubMed

    Xuetao, Shi; Fusheng, You; Feng, Fu; Ruigang, Liu; Xiuzhen, Dong

    2005-01-01

    To establish a high precision data acquisition system for multi-frequency electrical impedance tomography (EIT), a series of methods were introduced. Those methods include building a driving signal with up to four frequency components to diminish the effect of the dynamic change of tissues resistivity, extracting the impedance information by a digital demodulator that can improve the SNR by 8 times. The system that established can work at a wide range from 1.6kHz to 380kHz. Its CMRR is 74dB at 100kHz. The output impedance of current source is 2MΩ at that frequency. And measurement precision on a 100ohm resistor is better than -80dB in full bandwidth. Both the quasi-static and the dynamic imaging results based on a saline tank can reflect the resistivity changes inside the phantom clearly. Therefore, the system was competent in multifrequency EIT research work.

  11. Communication: High precision sub-Doppler infrared spectroscopy of the HeH{sup +} ion

    SciTech Connect

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

    2014-09-14

    The hydrohelium cation, HeH{sup +}, serves as an important benchmark for ab initio calculations that take into account non-adiabatic, relativistic, and quantum electrodynamic effects. Such calculations are capable of predicting molecular transitions to an accuracy of ∼300 MHz or less. However, in order to continue to push the boundaries on these calculations, new measurements of these transitions are required. Here we measure seven rovibrational transitions in the fundamental vibrational band to a precision of ∼1 MHz using the technique of Noise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy. These newly measured transitions are included in a fit to the rotation-vibration term values to derive refined spectroscopic constants in the v = 0 and v = 1 vibrational states, as well as to calculate rotation-vibration energy levels with high precision.

  12. A high precision optical angle measuring instrument for large optical axis offsets

    NASA Astrophysics Data System (ADS)

    Xie, Jing; Tan, Zuojun

    2014-09-01

    In many industrial activities such as manufacturing and inspection, optical axis offsets measurement is an essential process for keeping and improving the quality of products. The laser autocollimation method is improved to detect the large angular displacement with high precision by using a re-imaging technology. A large optical screen made of frosted glass is located at the focal position of the objective lens instead of the detector. A precision CCD imaging system was employed to measure the displacement of the light spot on the optical screen. The sub-pixel position of center of the light spot can be obtained accurately through the centroid and Gaussian fit methods. The actual test results show that the total systematic error of the optical angle measuring instrument in the mode of measuring the range 8°×8° does not exceed 0.16'.

  13. High-precision lattice calculation of the decay constants fB and fBs

    NASA Astrophysics Data System (ADS)

    Detar, Carleton; Bazavov, Alexei; Bernard, Claude; Bouchard, Christopher; Brown, Nathan; Du, Daping; El Khadra, Aida; Freeland, Elizabeth; Gamiz, Elvira; Gottlieb, Steven; Na, Heechang; Heller, Urs; Komijani, Javad; Kronfeld, Andreas; Laiho, John; MacKenzie, Paul; Neil, Ethan; Simone, James; Sugar, Robert; Toussaint, Douglas; van de Water, Ruth; Zhou, Ran; Fermilab Lattice Collaboration; MILC Collaboration

    2016-03-01

    We present preliminary, high-precision results for the hadronic decay constants of the B and the Bs mesons from lattice QCD simulations using a highly improved quark formulation for both heavy and light valence quarks. Calculations are carried out with several heavy valence-quark masses on lattice ensembles with 2+1+1 flavors of HISQ sea quarks at five lattice spacings and three light sea quark mass ratios mud /ms , including approximately physical sea quark masses. This range of parameters provides excellent control of the continuum limit and of heavy-quark discretization errors. Present affiliation: Ohio Supercomputer Center.

  14. Lightweight Metal Matrix Composite Segmented for Manufacturing High-Precision Mirrors

    NASA Technical Reports Server (NTRS)

    Vudler, Vladimir

    2012-01-01

    High-precision mirrors for space applications are traditionally manufactured from one piece of material, such as lightweight glass sandwich or beryllium. The purpose of this project was to develop and test the feasibility of a manufacturing process capable of producing mirrors out of welded segments of AlBeMet(Registered Trademark) (AM162H). AlBeMet(Registered Trademark) is a HIP'd (hot isostatic pressed) material containing approximately 62% beryllium and 38% aluminum. As a result, AlBeMet shares many of the benefits of both of those materials for use in high performance mirrors, while minimizing many of their weaknesses.

  15. Precision blood-leak detector with high long-time stability

    NASA Astrophysics Data System (ADS)

    Georgiadis, Christos; Kleuver, Wolfram

    1999-11-01

    With this publication a precision blood-leak-detector is presented. The blood-leak-detector is used for recognition of fractures in the dialyzer of a kidney-machine. It has to detect safely a blood flow of ml/min to exclude any risk for the patient. A lot of systems exist for blood-leak-detection. All of them use the same principle. They detect the light absorption in the dialyze fluid. The actual used detectors are inferior to the new developed sensor in resolution and long-time stability. Regular test of the existing systems and high failure rates are responsible for the high maintenance.

  16. Flux Leakage Measurements for Defect Characterization Using a High Precision 3-AXIAL Gmr Magnetic Sensor

    NASA Astrophysics Data System (ADS)

    Pelkner, M.; Blome, M.; Reimund, V.; Thomas, H.-M.; Kreutzbruck, M.

    2011-06-01

    High-precision magnetic field sensors are of increasing interest in non destructive testing (NDT). In particular GMR-sensors (giant magneto resistance) are qualified because of their high sensitivity, high signal-to-noise ratio and high spatial resolution. With a GMR-gradiometer and a 3D-GMR-magnetometer we performed magnetic flux leakage measurements of artificial cracks and cracks of a depth of ≤50 μm still could be dissolved with a sufficient high signal-to-noise ratio. A semi-analytic magnetic dipole model that allows realistic GMR sensor characteristics to be incorporated is used for swiftly predicting magnetic stray fields. The reliable reconstruction based on measurements of artificial rectangular-shaped defects is demonstrated.

  17. ACT3: A High-speed, High-Precision Electrical Impedance Tomograph

    PubMed Central

    Cook, Raymond D.; Saulnier, Gary J.; Gisser, David G.; Goble, John C.; Newell, JC.; Isaacson, David

    2016-01-01

    This paper presents the design, implementation, and performance of Rensselaer’s third-generation Adaptive Current Tomograph, ACT3. This system uses 32 current sources and 32 phase-sensitive voltmeters to make a 32-electrode system that is capable of applying arbitrary spatial patterns of current. The instrumentation provides 16 b precision on both the current values and the real and reactive voltage readings and can collect the data for a single image in 133 ms. Additionally, the instrument is able to automatically calibrate its voltmeters and current sources and adjust the current source output impedance under computer control. The major system components are discussed in detail and performance results are given. Images obtained using stationary agar targets and a moving pendulum in a phantom as well as in vivo resistivity profiles showing human respiration are shown. PMID:7927393

  18. Wide-capture-range, high-precision wavelength stabilization within ±50 MHz for flexible-grid wavelength division multiplexing by photomixing technique

    NASA Astrophysics Data System (ADS)

    Tsuboi, Jun; Kuboki, Takeshi; Kato, Kazutoshi

    2016-08-01

    The lasers for the flexible-grid wavelength division multiplexing (WDM) system are required to have high precision of wavelength stability. Previously, we proposed the wavelength-controlling system of the distributed feedback laser diode (DFB-LD) with the photomixing technique and a microwave filter to precisely measure the optical frequency error from the target value. To enlarge the wavelength-capture range, we improve the system to detect the wavelength error with two different microwave filters in parallel. Experimental results show that the wavelength-capture range is extended up to 4 GHz while the wavelength error is still kept within ±50 MHz.

  19. High-precision mass measurements of 25Al and 30P at JYFLTRAP

    NASA Astrophysics Data System (ADS)

    Canete, L.; Kankainen, A.; Eronen, T.; Gorelov, D.; Hakala, J.; Jokinen, A.; Kolhinen, V. S.; Koponen, J.; Moore, I. D.; Reinikainen, J.; Rinta-Antila, S.

    2016-05-01

    The masses of the astrophysically relevant nuclei 25Al and 30P have been measured with a Penning trap for the first time. The mass-excess values for 25Al ( Δ = -8915.962(63) keV) and 30P ( Δ = -20200.854(64) keV) obtained with the JYFLTRAP double Penning trap mass spectrometer are in good agreement with the Atomic Mass Evaluation 2012 values but ≈ 5-10 times more precise. A high precision is required for calculating resonant proton-capture rates of astrophysically important reactions 25Al ( p, γ)26Si and 30P( p, γ)31S . In this work, Q_{(p,γ)} = 5513.99(13) keV and Q_{(p,γ)} = 6130.64(24) keV were obtained for 25Al and 30P , respectively. The effect of the more precise values on the resonant proton-capture rates has been studied. In addition to nuclear astrophysics, the measured QEC value of 25Al , 4276.805(45) keV, is relevant for studies of T = 1/2 mirror beta decays which have a potential to be used to test the Conserved Vector Current hypothesis.

  20. A micro-computer based system for high precision temperature measurement using Platinum RTD's

    NASA Astrophysics Data System (ADS)

    Matthew, W. T.

    1982-07-01

    A micro-computer controlled system for 10 channel high precision temperature data acquisition has been developed. The temperature sensing elements are Platinum Resistance Thermometer Devices (RTD's). Probe construction, using standard, commercially available RTD elements is described and wiring and switching requirements for the 4-wire resistance measurements are noted. The system consists of a Digital Equipment Corp. MINC-11 Computer linked, via IEEE-488 interface bus cables, to a HP (Hewlett-Packard) 34555A Digital Volt/Ohm Meter, an HP-3495A Scanner/Multiplexer, and, during calibration, a HP 2804A Quartz Thermometer. Two programs are employed: one for probe calibration and the other for the temperature measurement application. In the calibration program, the ten probes are individually calibrated against the Quartz Thermometer which has an absolute accuracy specification of + or 0.04 C. A proportional control water bath having a thermal stability specification of + or - 0.004 C provided the common thermal medium during calibration. Currently a three point calibration spanning 6 C (37 to 43 C) is employed. The individual probe constants are computed and recorded on a computer file for access via the temperature measurement program. An initial evaluation of the precision of the calibrated RTD system against the Quartz Thermometer reading yielded an overall precision of + or - 0.0004 C and worst case error of less than + or - 0.01 C.

  1. High-precision Stark shift measurements in excited states of indium using an atomic beam

    NASA Astrophysics Data System (ADS)

    Majumder, P. K.; Carter, A. L.; Augenbraun, B. L.; Rupasinghe, P. M.; Vilas, N. B.

    2016-05-01

    A recent precision measurement in our group of the indium scalar polarizability within the 410 nm 5p1 / 2 --> 6s1 / 2 transition showed excellent agreement with ab initio atomic theory. We are now completing a measurement of the polarizability within the 6s1 / 2 --> 6p1 / 2 excited-state transition. In our experiment, two external cavity semiconductor diode lasers interact transversely with a collimated indium atomic beam. We tune the 410 nm laser to the 5p1 / 2 --> 6s1 / 2 transition, keeping the laser locked to the exact Stark-shifted resonance frequency. We overlap a 1343 nm infrared laser to reach the 6p1 / 2 state. The very small infrared absorption in our atomic beam is detected using two-tone FM spectroscopy. Monitoring the two-step excitation signal in a field-free supplemental vapor cell provides frequency reference and calibration. Precisely calibrated electric fields of 5 - 15 kV/cm produce Stark shifts of order 100 MHz for this excited state. Experimental details, latest results, and comparison to theory will be discussed. In the near future, The same infrared laser will be tuned to 1291 nm to study the scalar and tensor polarizability of the 6p3 / 2 excited state providing a distinct test of atomic theory. Work supported by NSF Grant # 1404206.

  2. High throughput proteome-wide precision measurements of protein expression using mass spectrometry

    SciTech Connect

    Pasa-Tolic, L.; Jensen, P.K.; Anderson, G.A.; Lipton, M.S.; Peden, K.K.; Martinovic, S.; Tolic, N.; Bruce, J.E.; Smith, R.D.

    1999-09-01

    In contrast to a cell's virtually static genome, the proteome, the protein complement expressed by an organism, continually changes in response to external stimuli and internal processes. Global gene expression analysis at the mRNA level (i.e., transcriptome) has recently become feasible based on the serial analysis of gene expression and oligonucleotide micro-array assays. These techniques allow the activation states of thousands of genes to be polled simultaneously for a tissue or cell population. However, assays that measure mRNA abundances rather than the functional gene products (i.e., proteins) are uninformative with regard to protein modifications, and can poorly reflect protein abundances due to differences in stabilities, expression rates, etc., for both the mRNAs and proteins. The authors have developed an approach utilizing organisms cultured in stable-isotope labeled media (e.g., rare-isotope depleted and normal) to provide effective internal calibrants for all detected proteins, thus enabling precise proteome-wide measurement of changes in protein abundances resulting from cellular perturbations. The two (or more) isotopically distinctive cell populations are mixed prior to sample processing steps, eliminating all experimental variables associated with cell lysis, separation, and mass spectrometric analysis. Changes in relative protein abundances are thus precisely reflected by the ratio of two isotopically different and resolvable versions of each protein.

  3. A High Precision Method for Quantitative Measurements of Reactive Oxygen Species in Frozen Biopsies

    PubMed Central

    Lindgren, Mikael; Gustafsson, Håkan

    2014-01-01

    Objective An electron paramagnetic resonance (EPR) technique using the spin probe cyclic hydroxylamine 1-hydroxy-3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine (CMH) was introduced as a versatile method for high precision quantification of reactive oxygen species, including the superoxide radical in frozen biological samples such as cell suspensions, blood or biopsies. Materials and Methods Loss of measurement precision and accuracy due to variations in sample size and shape were minimized by assembling the sample in a well-defined volume. Measurement was carried out at low temperature (150 K) using a nitrogen flow Dewar. The signal intensity was measured from the EPR 1st derivative amplitude, and related to a sample, 3-carboxy-proxyl (CP•) with known spin concentration. Results The absolute spin concentration could be quantified with a precision and accuracy better than ±10 µM (k = 1). The spin concentration of samples stored at −80°C could be reproduced after 6 months of storage well within the same error estimate. Conclusion The absolute spin concentration in wet biological samples such as biopsies, water solutions and cell cultures could be quantified with higher precision and accuracy than normally achievable using common techniques such as flat cells, tissue cells and various capillary tubes. In addition; biological samples could be collected and stored for future incubation with spin probe, and also further stored up to at least six months before EPR analysis, without loss of signal intensity. This opens for the possibility to store and transport incubated biological samples with known accuracy of the spin concentration over time. PMID:24603936

  4. The New Kilogram Definition and its Implications for High-Precision Mass Tolerance Classes.

    PubMed

    Abbott, Patrick J; Kubarych, Zeina J

    2013-01-01

    The SI unit of mass, the kilogram, is the only remaining artifact definition in the seven fundamental units of the SI system. It will be redefined in terms of the Planck constant as soon as certain experimental conditions, based on recommendations of the Consultative Committee for Mass and Related Quantities (CCM) are met. To better reflect reality, the redefinition will likely be accompanied by an increase in the uncertainties that National Metrology Institutes (NMIs) pass on to customers via artifact dissemination, which could have an impact on the reference standards that are used by secondary calibration laboratories if certain weight tolerances are adopted for use. This paper will compare the legal metrology requirements for precision mass calibration laboratories after the kilogram is redefined with the current capabilities based on the international prototype kilogram (IPK) realization of the kilogram.

  5. Indirect Terahertz Spectroscopy of Molecular Ions Using Highly Accurate and Precise Mid-Ir Spectroscopy

    NASA Astrophysics Data System (ADS)

    Mills, Andrew A.; Ford, Kyle B.; Kreckel, Holger; Perera, Manori; Crabtree, Kyle N.; McCall, Benjamin J.

    2009-06-01

    With the advent of Herschel and SOFIA, laboratory methods capable of providing molecular rest frequencies in the terahertz and sub-millimeter regime are increasingly important. As of yet, it has been difficult to perform spectroscopy in this wavelength region due to the limited availability of radiation sources, optics, and detectors. Our goal is to provide accurate THz rest frequencies for molecular ions by combining previously recorded microwave transitions with combination differences obtained from high precision mid-IR spectroscopy. We are constructing a Sensitive Resolved Ion Beam Spectroscopy setup which will harness the benefits of kinematic compression in a molecular ion beam to enable very high resolution spectroscopy. This ion beam is interrogated by continuous-wave cavity ringdown spectroscopy using a home-made widely tunable difference frequency laser that utilizes two near-IR lasers and a periodically-poled lithium niobate crystal. Here, we report our efforts to optimize our ion beam spectrometer and to perform high-precision and high-accuracy frequency measurements using an optical frequency comb. footnote

  6. Thermoresponsive Ultrathin Membranes with Precisely Tuned Nanopores for High-Flux Separation.

    PubMed

    Zhu, Yuzhang; Gao, Shoujian; Hu, Liang; Jin, Jian

    2016-06-01

    With the growing demand for small- and large-scale bioprocesses, advanced membranes with high energy efficiency are highly required. However, conventional polymer-based membranes often have to sacrifice selectivity for permeability. In this work, we report the fabrication of a thermoresponsive composite ultrathin membrane with precisely controlled nanopores for high-throughput separation. The composite membrane is made by grafting a PEG analogue thermoresponsive copolymer onto an ultrathin single-wall carbon nanotubes (SWCNTs) membrane via π-π interaction with no use of the common "grafting from" synthesis approach. The composite membrane exhibits ultrahigh water permeation flux as high as 6430 L m(-2) h(-1) at 40 °C, and more importantly, the pore size of the membrane could be finely adjusted by utilizing the thermoresponsive property of the grafted copolymer. With the temperature changing below and above the lower critical solution temperature (LCST) of the copolymer, the effective pore size of the membrane can be tuned precisely between approximately 12 and 14 nm, which could be applied to effectively separate materials with very small size differences through size sieving. PMID:27177239

  7. 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.

  8. 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

  9. Precision equation of state measurements on hydrocarbons in the high energy density regime

    NASA Astrophysics Data System (ADS)

    Barrios Garcia, Maria Alejandra

    The equation of state (EOS) of materials at extreme temperatures and pressures is of interest to astrophysics, high-energy-density physics, and inertial confinement fusion (ICF). The behavior of hydrocarbon materials at high-pressures (>1 Mbar) is essential to the understanding of ablator materials for ICF ignition targets. The EOS measurements on CHX presented here provide benchmark behavior of hydrocarbons under extreme conditions and the effect of stoichiometry (i.e. C:H ratio) on that behavior. Advances in diagnostics and analysis have made it possible to perform highly accurate measurements of shock velocity to ˜1% precision in transparent materials. This refines the impedance-match (IM) technique for laser-driven shock experiments producing precise EOS data at extreme pressures using a transparent standard such as alpha-quartz. The OMEGA laser was used to produce principal (single-shock) Hugoniot EOS measurements on polystyrene (CH), polypropylene (CH2), Glow-Discharge-Polymer (GDP) (C43H56O), and Germanium-doped GDP at shock pressures of 1--10 Mbar, with an alpha-quartz standard. This precision data tightly constrains the Hugoniot behavior of these hydrocarbons, even with the inclusion of systematic uncertainties inherent in the IM technique. A novel target design providing double-shock (re-shock) measurements along with principal Hugoniot data is presented. Results of the single-and double-shock experiments on these hydrocarbons are presented and compared to various EOS models. Temperature measurements are presented for CH and CH2; measuring both the thermal and kinematic behavior of these materials provides their complete shock EOS. Reflectance measurements on CH and CH2 show that both hydrocarbons transition from transparent insulators to reflecting conductors at pressures of 1 to 2 Mbar.

  10. A novel approach for high precision rapid potentiometric titrations: application to hydrazine assay.

    PubMed

    Sahoo, P; Malathi, N; Ananthanarayanan, R; Praveen, K; Murali, N

    2011-11-01

    We propose a high precision rapid personal computer (PC) based potentiometric titration technique using a specially designed mini-cell to carry out redox titrations for assay of chemicals in quality control laboratories attached to industrial, R&D, and nuclear establishments. Using this technique a few microlitre of sample (50-100 μl) in a total volume of ~2 ml solution can be titrated and the waste generated after titration is extremely low comparing to that obtained from the conventional titration technique. The entire titration including online data acquisition followed by immediate offline analysis of data to get information about concentration of unknown sample is completed within a couple of minutes (about 2 min). This facility has been created using a new class of sensors, viz., pulsating sensors developed in-house. The basic concept in designing such instrument and the salient features of the titration device are presented in this paper. The performance of the titration facility was examined by conducting some of the high resolution redox titrations using dilute solutions--hydrazine against KIO(3) in HCl medium, Fe(II) against Ce(IV) and uranium using Davies-Gray method. The precision of titrations using this innovative approach lies between 0.048% and 1.0% relative standard deviation in different redox titrations. With the evolution of this rapid PC based titrator it was possible to develop a simple but high precision potentiometric titration technique for quick determination of hydrazine in nuclear fuel dissolver solution in the context of reprocessing of spent nuclear fuel in fast breeder reactors.

  11. High-Precision Dispensing of Nanoliter Biofluids on Glass Pedestal Arrays for Ultrasensitive Biomolecule Detection.

    PubMed

    Chen, Xiaoxiao; Liu, Yang; Xu, QianFeng; Zhu, Jing; Poget, Sébastien F; Lyons, Alan M

    2016-05-01

    Precise dispensing of nanoliter droplets is necessary for the development of sensitive and accurate assays, especially when the availability of the source solution is limited. Conventional approaches are limited by imprecise positioning, large shear forces, surface tension effects, and high costs. To address the need for precise and economical dispensing of nanoliter volumes, we developed a new approach where the dispensed volume is dependent on the size and shape of defined surface features, thus freeing the dispensing process from pumps and fine-gauge needles requiring accurate positioning. The surface we fabricated, called a nanoliter droplet virtual well microplate (nVWP), achieves high-precision dispensing (better than ±0.5 nL or ±1.6% at 32 nL) of 20-40 nL droplets using a small source drop (3-10 μL) on isolated hydrophilic glass pedestals (500 μm on a side) bonded to arrays of polydimethylsiloxane conical posts. The sharp 90° edge of the glass pedestal pins the solid-liquid-vapor triple contact line (TCL), averting the wetting of the glass sidewalls while the fluid is prevented from receding from the edge. This edge creates a sufficiently large energy barrier such that microliter water droplets can be poised on the glass pedestals, exhibiting contact angles greater >150°. This approach relieves the stringent mechanical alignment tolerances required for conventional dispensing techniques, shifting the control of dispensed volume to the area circumscribed by the glass edge. The effects of glass surface chemistry and dispense velocity on droplet volume were studied using optical microscopy and high-speed video. Functionalization of the glass pedestal surface enabled the selective adsorption of specific peptides and proteins from synthetic and natural biomolecule mixtures, such as venom. We further demonstrate how the nVWP dispensing platform can be used for a variety of assays, including sensitive detection of proteins and peptides by fluorescence

  12. Asynchronous RTK precise DGNSS positioning method for deriving a low-latency high-rate output

    NASA Astrophysics Data System (ADS)

    Liang, Zhang; Hanfeng, Lv; Dingjie, Wang; Yanqing, Hou; Jie, Wu

    2015-07-01

    Low-latency high-rate (1 Hz) precise real-time kinematic (RTK) can be applied in high-speed scenarios such as aircraft automatic landing, precise agriculture and intelligent vehicle. The classic synchronous RTK (SRTK) precise differential GNSS (DGNSS) positioning technology, however, is not able to obtain a low-latency high-rate output for the rover receiver because of long data link transmission time delays (DLTTD) from the reference receiver. To overcome the long DLTTD, this paper proposes an asynchronous real-time kinematic (ARTK) method using asynchronous observations from two receivers. The asynchronous observation model (AOM) is developed based on undifferenced carrier phase observation equations of the two receivers at different epochs with short baseline. The ephemeris error and atmosphere delay are the possible main error sources on positioning accuracy in this model, and they are analyzed theoretically. In a short DLTTD and during a period of quiet ionosphere activity, the main error sources decreasing positioning accuracy are satellite orbital errors: the "inverted ephemeris error" and the integration of satellite velocity error which increase linearly along with DLTTD. The cycle slip of asynchronous double-differencing carrier phase is detected by TurboEdit method and repaired by the additional ambiguity parameter method. The AOM can deal with synchronous observation model (SOM) and achieve precise positioning solution with synchronous observations as well, since the SOM is only a specific case of AOM. The proposed method not only can reduce the cost of data collection and transmission, but can also support the mobile phone network data link transfer mode for the data of the reference receiver. This method can avoid data synchronizing process besides ambiguity initialization step, which is very convenient for real-time navigation of vehicles. The static and kinematic experiment results show that this method achieves 20 Hz or even higher rate output in

  13. A Fission Time Projection Chamber for High Precision Cross Section Measurements

    NASA Astrophysics Data System (ADS)

    Snyder, Lucas; Greife, Uwe

    2010-11-01

    The design of next generation nuclear reactors and other nuclear applications are increasingly dependent on advanced simulations. Sensitivity studies have shown a need for high precision nuclear data to improve the predictive capabilities of these simulations. The Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) collaboration has constructed and is currently testing a prototype Time Projection Chamber (TPC) designed to measure fission cross sections to a higher accuracy than is capable with existing technology. In this talk, I will discuss the status of the fission TPC and progress on collecting the first set of data from ^252Cf spontaneous fission.

  14. On the recovery of gravity anomalies from high precision altimeter data

    NASA Technical Reports Server (NTRS)

    Lelgemann, D.

    1976-01-01

    A model for the recovery of gravity anomalies from high precision altimeter data is derived which consists of small correction terms to the inverse Stokes' formula. The influence of unknown sea surface topography in the case of meandering currents such as the Gulf Stream is discussed. A formula was derived in order to estimate the accuracy of the gravity anomalies from the known accuracy of the altimeter data. It is shown that for the case of known harmonic coefficients of lower order the range of integration in Stokes inverse formula can be reduced very much.

  15. High precision measurements of the neutron spin structure in Hall A at Jlab

    SciTech Connect

    Annand, R M; Cates, G; Cisbani, E; Franklin, G B; Liyanage, N; Puckett, A; Rosner, G; Wojtsekhowski, B; Zheng, X

    2012-04-01

    Conclusions of this presentation are: (1) JLab energy upgrade will offer new exciting opportunities to study the nucleon (spin) structure such as high precision, unexplored phase space, flavor decomposition; (2) Large technological efforts is in progress to optimally exploit these opportunities; (3) HallA will be the first hall to get the new beam, first experiment expected to run in 2014; (4) A1n likely one of the first experiments to take data in the new 12 GeV era; and (5) SIDIS exp. will follow in couple of years.

  16. High-precision gamma-ray spectroscopy for enhancing production and application of medical isotopes

    NASA Astrophysics Data System (ADS)

    McCutchan, E. A.; Sonzogni, A. A.; Smith, S. V.; Muench, L.; Nino, M.; Greene, J. P.; Carpenter, M. P.; Zhu, S.; Chillery, T.; Chowdhury, P.; Harding, R.; Lister, C. J.

    2015-10-01

    Nuclear medicine is a field which requires precise decay data for use in planning radionuclide production and in imaging and therapeutic applications. To address deficiencies in decay data, sources of medical isotopes were produced and purified at the Brookhaven Linear Isotope Producer (BLIP) then shipped to Argonne National Laboratory where high-precision, gamma-ray measurements were performed using Gammasphere. New decay schemes for a number of PET isotopes and the impact on dose calculations will be presented. To investigate the production of next-generation theranostic or radiotherapeutic isotopes, cross section measurements with high energy protons have also been explored at BLIP. The 100-200 MeV proton energy regime is relatively unexplored for isotope production, thus offering high discovery potential but at the same time a challenging analysis due to the large number of open channels at these energies. Results of cross sections deduced from Compton-suppressed, coincidence gamma-ray spectroscopy performed at Lowell will be presented, focusing on the production of platinum isotopes by irradiating natural platinum foils with 100 to 200 MeV protons. DOE Isotope Program is acknowledged for funding ST5001030. Work supported by the US DOE under Grant DE-FG02-94ER40848 and Contracts DE-AC02-98CH10946 and DE-AC02-06CH11357.

  17. Prediction of the applicability of active damping elements in high-precision machines

    NASA Astrophysics Data System (ADS)

    Holterman, Jan; de Vries, Theo J. A.

    2004-07-01

    The Smart Disc project at the Drebbel Institute of the University of Twente is aimed at the development of active structural elements for high-precision machines. The active elements consist of a piezoelectric position actuator and a collocated piezoelectric force sensor. As the actuators and sensors are collocated, the elements are especially suited for implementing robust active damping. The decision whether or not to incorporate active damping elements in a high-precision machine should ideally be made in an early design stage, i.e., at a time at which only limited knowledge of the vibration problem is available. Despite the uncertainties that may exist at that stage, one would like to be able to roughly predict the amount of damping that could possibly be obtained. For that reason, the present paper is concerned with the development of an analysis tool that may help in predicting the applicability of active damping elements in a mechanical structure of which only a rough model is available. Based on extensive simulations, several practical rules of thumb are given for the requirements for the mechanical structure and the active elements, in order to enable the realisation of relative damping values as high as 10%.

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

    NASA Astrophysics Data System (ADS)

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

    2016-01-01

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

  19. An Online Gravity Modeling Method Applied for High Precision Free-INS.

    PubMed

    Wang, Jing; Yang, Gongliu; Li, Jing; Zhou, Xiao

    2016-01-01

    For real-time solution of inertial navigation system (INS), the high-degree spherical harmonic gravity model (SHM) is not applicable because of its time and space complexity, in which traditional normal gravity model (NGM) has been the dominant technique for gravity compensation. In this paper, a two-dimensional second-order polynomial model is derived from SHM according to the approximate linear characteristic of regional disturbing potential. Firstly, deflections of vertical (DOVs) on dense grids are calculated with SHM in an external computer. And then, the polynomial coefficients are obtained using these DOVs. To achieve global navigation, the coefficients and applicable region of polynomial model are both updated synchronously in above computer. Compared with high-degree SHM, the polynomial model takes less storage and computational time at the expense of minor precision. Meanwhile, the model is more accurate than NGM. Finally, numerical test and INS experiment show that the proposed method outperforms traditional gravity models applied for high precision free-INS. PMID:27669261

  20. Design of a fast and high-precision polygonal scanner for HDTV

    NASA Astrophysics Data System (ADS)

    Risse, Stefan; Guyenot, Volker

    1997-07-01

    With the continuing development of laser-display-technology, a new possibility for the production high level image projection is forwarded and with it the beginning of a new era in television: TV picture formats previously thought impossible, the sharpness, color intensity and unsurpassed resolution of which make the dream of home cinema a reality. The key to this experience is visible laser light in red, green and blue, projected on a screen with the aid of horizontal and vertical deflection units. In this paper, a primarily horizontal deflection system in the form of a rotating polygonal scanner is described. The design of this scanner assembly combines a double spherical air bearing with an integrated polygonal mirror for deflection and a high torque inside drive for quickly reaching high rotation. The Fraunhofer Institute of Applied Optics and Precision Engineering (IOF Jena) develops, from conception to assembled prototype, new self-acting precision bearing systems. This new scanner solution developed out of IOF's previous developments resulting in the first ever sealed, minimal-maintenance, self- acting bearing.

  1. Optical recording of neuronal spiking activity from unbiased populations of neurons with high spike detection efficiency and high temporal precision.

    PubMed

    Ranganathan, Gayathri N; Koester, Helmut J

    2010-09-01

    Activity in populations of neurons is essential for cortical function including signaling of information and signal transport. Previous methods have made advances in recording activity from many neurons but have both technical and analytical limitations. Here we present an optical method, dithered random-access functional calcium imaging, to record somatic calcium signals from up to 100 neurons, in vitro and in vivo. We further developed a maximum-likelihood deconvolution algorithm to detect spikes and precise spike timings from the recorded calcium fluorescence signals. Spike detection efficiency and spike timing detection was determined in acute slices of juvenile mice. The results indicate that the combination of the two methods detected precise spiking activity from unbiased and spatially distributed populations of neurons in acute slices with high efficiency of spike detection (>97%), low rate of false positives (0.0023 spikes/s), and high temporal precision. The results further indicate that there is only a small window of excitation intensities where high spike detection can be achieved consistently.

  2. Precision control of lesions by high-intensity focused ultrasound cavitation-based histotripsy through varying pulse duration.

    PubMed

    Xu, Jin; Bigelow, Timothy A; Nagaraju, Ravindra

    2013-07-01

    The goal of this experimental study was to explore the feasibility of acquiring controllable precision through varying pulse duration for lesions generated by cavitation-based histotripsy. Histotripsy uses high-intensity focused ultrasound (HIFU) at low duty factor to create energetic bubble clouds inside tissue to liquefy a region. It uses cavitation-mediated mechanical effects while minimizing heating, and has the advantages of real-time monitoring and lesion fidelity to treatment planning. In our study, histotripsy was applied to three groups of tissue-mimicking agar samples of different stiffnesses (29.4 ± 5.3, 44.8 ± 5.9, and 66.4 ± 7.1 kPa). B-mode imaging was used first to quantify bubble cluster dimensions in both water and agar. Then, a 4.5-mm-wide square (lateral to the focal plane) was scanned in a raster pattern with a step size of 0.75 mm in agar histotripsy experiments to estimate equivalent bubble cluster dimensions based on the histotripsyinduced damage. The 15-s exposure at each treatment location comprised 5000 sine-wave tone bursts at a spatial-peak pulseaverage intensity of 41.1 kW/cm2, with peak compressional and rarefactional pressures of 102 and 17 MPa, respectively. The results showed that bubble cluster width and length increased with pulse duration and decreased with agar stiffness. Therefore, a significant improvement in histotripsy precision could be achieved by reducing the pulse duration.

  3. High-precision comparison of the antiproton-to-proton charge-to-mass ratio.

    PubMed

    Ulmer, S; Smorra, C; Mooser, A; Franke, K; Nagahama, H; Schneider, G; Higuchi, T; Van Gorp, S; Blaum, K; Matsuda, Y; Quint, W; Walz, J; Yamazaki, Y

    2015-08-13

    Invariance under the charge, parity, time-reversal (CPT) transformation is one of the fundamental symmetries of the standard model of particle physics. This CPT invariance implies that the fundamental properties of antiparticles and their matter-conjugates are identical, apart from signs. There is a deep link between CPT invariance and Lorentz symmetry--that is, the laws of nature seem to be invariant under the symmetry transformation of spacetime--although it is model dependent. A number of high-precision CPT and Lorentz invariance tests--using a co-magnetometer, a torsion pendulum and a maser, among others--have been performed, but only a few direct high-precision CPT tests that compare the fundamental properties of matter and antimatter are available. Here we report high-precision cyclotron frequency comparisons of a single antiproton and a negatively charged hydrogen ion (H(-)) carried out in a Penning trap system. From 13,000 frequency measurements we compare the charge-to-mass ratio for the antiproton (q/m)p- to that for the proton (q/m)p and obtain (q/m)p-/(q/m)p − 1 =1(69) × 10(-12). The measurements were performed at cyclotron frequencies of 29.6 megahertz, so our result shows that the CPT theorem holds at the atto-electronvolt scale. Our precision of 69 parts per trillion exceeds the energy resolution of previous antiproton-to-proton mass comparisons as well as the respective figure of merit of the standard model extension by a factor of four. In addition, we give a limit on sidereal variations in the measured ratio of <720 parts per trillion. By following the arguments of ref. 11, our result can be interpreted as a stringent test of the weak equivalence principle of general relativity using baryonic antimatter, and it sets a new limit on the gravitational anomaly parameter of |α − 1| < 8.7 × 10(-7). PMID:26268189

  4. First high-precision differential abundance analysis of extremely metal-poor stars

    NASA Astrophysics Data System (ADS)

    Reggiani, Henrique; Meléndez, Jorge; Yong, David; Ramírez, Ivan; Asplund, Martin

    2016-02-01

    Context. Studies of extremely metal-poor stars indicate that chemical abundance ratios [X/Fe] have a root mean square scatter as low as 0.05 dex (12%). It remains unclear whether this reflects observational uncertainties or intrinsic astrophysical scatter arising from physical conditions in the interstellar medium at early times. Aims: We measure differential chemical abundance ratios in extremely metal-poor stars to investigate the limits of precision and to understand whether cosmic scatter or observational errors are dominant. Methods: We used high-resolution (R ~ 95 000) and high signal-to-noise (S/N = 700 at 5000 Å) HIRES/Keck spectra to determine high-precision differential abundances between two extremely metal-poor stars through a line-by-line differential approach. We determined stellar parameters for the star G64-37 with respect to the standard star G64-12. We performed EW measurements for the two stars for the lines recognized in both stars and performed spectral synthesis to study the carbon abundances. Results: The differential approach allowed us to obtain errors of σ(Teff) = 27 K, σ(log g) = 0.06 dex, σ( [Fe/H] ) = 0.02 dex and σ(vt) = 0.06 km s-1. We estimated relative chemical abundances with a precision as low as σ([X/Fe]) ≈ 0.01 dex. The small uncertainties demonstrate that there are genuine abundance differences larger than the measurement errors. The observed Li difference cannot be explained by the difference in mass because the less massive star has more Li. Conclusions: It is possible to achieve an abundance precision around ≈ 0.01-0.05 dex for extremely metal-poor stars, which opens new windows on the study of the early chemical evolution of the Galaxy. Table A.1 is also available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/586/A67

  5. A low noise and high precision linear power supply with thermal foldback protection

    NASA Astrophysics Data System (ADS)

    Carniti, P.; Cassina, L.; Gotti, C.; Maino, M.; Pessina, G.

    2016-05-01

    A low noise and high precision linear power supply was designed for use in rare event search experiments with macrobolometers. The circuit accepts at the input a "noisy" dual supply voltage up to ±15 V and gives at the output precise, low noise, and stable voltages that can be set between ±3.75 V and ±12.5 V in eight 1.25 V steps. Particular care in circuit design, component selection, and proper filtering results in a noise spectral density of 50 nV / √{ Hz } at 1 Hz and 20 nV / √{ Hz } white when the output is set to ±5 V. This corresponds to 125 nV RMS (0.8 μV peak to peak) between 0.1 Hz and 10 Hz, and 240 nV RMS (1.6 μV peak to peak) between 0.1 Hz and 100 Hz. The power supply rejection ratio (PSRR) of the circuit is 100 dB at low frequency, and larger than 40 dB up to high frequency, thanks to a proper compensation design. Calibration allows to reach a precision in the absolute value of the output voltage of ±70 ppm, or ±350 μV at ±5 V, and to reduce thermal drifts below ±1 ppm/∘C in the expected operating range. The maximum peak output current is about 6 A from each output. An original foldback protection scheme was developed that dynamically limits the maximum output current to keep the temperature of the output transistors within their safe operating range. An add-on card based on an ARM Cortex-M3 microcontroller is devoted to the monitoring and control of all circuit functionalities and provides remote communication via CAN bus.

  6. Optical test bench for high precision metrology and alignment of zoom sub-assembly components

    NASA Astrophysics Data System (ADS)

    Leprêtre, F.; Levillain, E.; Wattellier, B.; Delage, P.; Brahmi, D.; Gascon, A.

    2013-09-01

    Thales Angénieux (TAGX) designs and manufactures zoom lens assemblies for cinema applications. These objectives are made of mobile lens assemblies. These need to be precisely characterized to detect alignment, polishing or glass index homogeneity errors, which amplitude may range to a few hundreds of nanometers. However these assemblies are highly aberrated with mainly spherical aberration (>30 μm PV). PHASICS and TAGX developed a solution based on the use of a PHASICS SID4HR wave front sensor. This is based on quadri-wave lateral shearing interferometry, a technology known for its high dynamic range. A 100-mm diameter He:Ne source illuminates the lens assembly entrance pupil. The transmitted wave front is then directly measured by the SID4- HR. The measured wave front (WFmeas) is then compared to a simulation from the lens sub-assembly optical design (WFdesign). We obtain a residual wave front error (WFmanufactured), which reveals lens imperfections due to its manufacturing. WFmeas=WFdesign+(WFEradius+WFEglass+WFEpolish)=WF design + WFmanufactured The optical test bench was designed so that this residual wave front is measured with a precision below 100 nm PV. The measurement of fast F-Number lenses (F/2) with aberrations up to 30 μm, with a precision of 100 nm PV was demonstrated. This bench detects mismatches in sub-assemblies before the final integration step in the zoom. Pre-alignment is also performed in order to overpass the mechanical tolerances. This facilitates the completed zoom alignment. In final, productivity gains are expected due to alignment and mounting time savings.

  7. The research of the high precision universal stable reconnaissance platform in near space

    NASA Astrophysics Data System (ADS)

    Yang, Hong-tao; Cao, Jian-zhong; Fan, Zhe-yuan; Chen, Wei-ning

    2011-08-01

    The appliance of military was recognized more and more ,It is important that pod can bear the weight of the availability payload achieve the observation to the earth in 20km-100km area and work in the all-weather. The stable platform can load high imaging spectrometer, the thermal infrared imager, the infrared radiometer, the millimeter waves radar, the laser weapon and so on,in order to realize reconnaissance and attacking integrative and warning the long-distant missile. The stabilization accuracy of platform is prior to 20μrad and burden heavy load to the best of one's abilities. It used high precision velocity and acceleration gyroscope to fulfill the stabilization of the platform. Light-weight design by using new composite material and optimizing design. It was adapt to the near space environment better by structure design and simulation analysis.Enhance its basic frequency and sure the rigid of the frame platform .In addition, the structure of platform apply the two-axis and four-frame and use the method of FEA to fulfill the optimum design in order to attain the object of light-weight.In consider to the precision of the platform I establish the math model and make use of the monte carlo method to appraise and analysis the error that affect the precision of the platform. After emulating by the software of the Matlab to verify the results. It is apply the method that link the platform and aerocraft by mounting the no angular displacement shock absorbers on the elevator mechanism. This kind of design insulate the angular vibration and minish the linear vibration to ensure the image quality.

  8. Spectrophotometric high-precision seawater pH determination for use in underway measuring systems

    NASA Astrophysics Data System (ADS)

    Aßmann, S.; Frank, C.; Körtzinger, A.

    2011-10-01

    Autonomous sensors are required for a comprehensive documentation of the changes in the marine carbon system and thus to differentiate between its natural variability and anthropogenic impacts. Spectrophotometric determination of pH - a key variable of the seawater carbon system - is particularly suited to achieve precise and drift-free measurements. However, available spectrophotometric instruments are not suitable for integration into automated measurement systems (e.g. FerryBox) since they do not meet the major requirements of reliability, stability, robustness and moderate cost. Here we report on the development and testing of a~new indicator-based pH sensor that meets all of these requirements. This sensor can withstand the rough conditions during long-term deployments on ships of opportunity and is applicable to the open ocean as well as to coastal waters with a complex matrix and highly variable conditions. The sensor uses a high resolution CCD spectrometer as detector connected via optical fibers to a custom-made cuvette designed to reduce the impact of air bubbles. The sample temperature can be precisely adjusted (25 °C ± 0.006 °C) using computer-controlled power supplies and Peltier elements thus avoiding the widely used water bath. The overall setup achieves a measurement frequency of 1 min-1 with a precision of ±0.0007 pH units, an average offset of +0.0005 pH units to a reference system, and an offset of +0.0081 pH units to a certified standard buffer. Application of this sensor allows monitoring of seawater pH in autonomous underway systems, providing a key variable for characterization and understanding of the marine carbon system.

  9. A numerical method for determining highly precise electron energy distribution functions from Langmuir probe characteristics

    SciTech Connect

    Bang, Jin-Young; Chung, Chin-Wook

    2010-12-15

    Electron energy distribution functions (EEDFs) were determined from probe characteristics using a numerical ac superimposed method with a distortion correction of high derivative terms by varying amplitude of a sinusoidal perturbation voltage superimposed onto the dc sweep voltage, depending on the related electron energy. Low amplitude perturbation applied around the plasma potential represented the low energy peak of the EEDF exactly, and high amplitude perturbation applied around the floating potential was effective to suppress noise or distortion of the probe characteristic, which is fatal to the tail electron distribution. When a small random noise was imposed over the stabilized prove characteristic, the numerical differentiation method was not suitable to determine the EEDF, while the numerical ac superimposed method was able to obtain a highly precise EEDF.

  10. High-precision method for submicron-aperture fiber point-diffraction wavefront measurement.

    PubMed

    Wang, Daodang; Xu, Yangbo; Liang, Rongguang; Kong, Ming; Zhao, Jun; Zhang, Baowu; Li, Wei

    2016-04-01

    It is a key issue to measure the point-diffraction wavefront error, which determines the achievable accuracy of point-diffraction interferometer (PDI). A high-precision method based on shearing interferometry is proposed to measure submicron-aperture fiber point-diffraction wavefront with high numerical aperture (NA). To obtain the true shearing point-diffraction wavefront, a double-step calibration method based on three-dimensional coordinate reconstruction and symmetric lateral displacement compensation is proposed to calibrate the geometric aberration in the case of high NA and large lateral wavefront displacement. The calibration can be carried out without any prior knowledge about the system configuration parameters. With the true shearing wavefront, the differential Zernike polynomials fitting method is applied to reconstruct the point-diffraction wavefront. Numerical simulation and experiments have been carried out to demonstrate the accuracy and feasibility of the proposed measurement method, and a good measurement accuracy is achieved. PMID:27137002

  11. Experimental Summary: Very High Energy Cosmic Rays and their Interactions

    NASA Astrophysics Data System (ADS)

    Kampert, Karl-Heinz

    2013-06-01

    The XVII International Symposium on Very High Energy Cosmic Ray Interactions, held in August of 2012 in Berlin, was the first one in the history of the Symposium,where a plethora of high precision LHC data with relevance for cosmic ray physics was presented. This report aims at giving a brief summary of those measurements andit discusses their relevance for observations of high energy cosmic rays. Enormous progress has been made also in air shower observations and in direct measurements of cosmic rays, exhibiting many more structure in the cosmic ray energy spectrum than just a simple power law with a knee and an ankle. At the highest energy, the flux suppression may not be dominated by the GZK-effect but by the limiting energy of a nearby source or source population. New projects and application of new technologies promise further advances also in the near future. We shall discuss the experimental and theoretical progress in the field and its prospects for coming years.

  12. A novel approach for pulse width measurements with a high precision (8 ps RMS) TDC in an FPGA

    NASA Astrophysics Data System (ADS)

    Ugur, C.; Linev, S.; Michel, J.; Schweitzer, T.; Traxler, M.

    2016-01-01

    High precision time measurements are a crucial element in particle identification experiments, which likewise require pulse width information for Time-over-Threshold (ToT) measurements and charge measurements (correlated with pulse width). In almost all of the FPGA-based TDC applications, pulse width measurements are implemented using two of the TDC channels for leading and trailing edge time measurements individually. This method however, requires twice the number of resources. In this paper we present the latest precision improvements in the high precision TDC (8 ps RMS) developed before [1], as well as the novel way of measuring ToT using a single TDC channel, while still achieving high precision (as low as 11.7 ps RMS). The effect of voltage, generated by a DC-DC converter, over the precision is also discussed. Finally, the outcome of the temperature change over the pulse width measurement is shown and a correction method is suggested to limit the degradation.

  13. A High Precision Position Sensor Design and Its Signal Processing Algorithm for a Maglev Train

    PubMed Central

    Xue, Song; Long, Zhiqiang; He, Ning; Chang, Wensen

    2012-01-01

    High precision positioning technology for a kind of high speed maglev train with an electromagnetic suspension (EMS) system is studied. At first, the basic structure and functions of the position sensor are introduced and some key techniques to enhance the positioning precision are designed. Then, in order to further improve the positioning signal quality and the fault-tolerant ability of the sensor, a new kind of discrete-time tracking differentiator (TD) is proposed based on nonlinear optimal control theory. This new TD has good filtering and differentiating performances and a small calculation load. It is suitable for real-time signal processing. The stability, convergence property and frequency characteristics of the TD are studied and analyzed thoroughly. The delay constant of the TD is figured out and an effective time delay compensation algorithm is proposed. Based on the TD technology, a filtering process is introduced in to improve the positioning signal waveform when the sensor is under bad working conditions, and a two-sensor switching algorithm is designed to eliminate the positioning errors caused by the joint gaps of the long stator. The effectiveness and stability of the sensor and its signal processing algorithms are proved by the experiments on a test train during a long-term test run. PMID:22778582

  14. A high-precision sampling scheme to assess persistence and transport characteristics of micropollutants in rivers.

    PubMed

    Schwientek, Marc; Guillet, Gaëlle; Rügner, Hermann; Kuch, Bertram; Grathwohl, Peter

    2016-01-01

    Increasing numbers of organic micropollutants are emitted into rivers via municipal wastewaters. Due to their persistence many pollutants pass wastewater treatment plants without substantial removal. Transport and fate of pollutants in receiving waters and export to downstream ecosystems is not well understood. In particular, a better knowledge of processes governing their environmental behavior is needed. Although a lot of data are available concerning the ubiquitous presence of micropollutants in rivers, accurate data on transport and removal rates are lacking. In this paper, a mass balance approach is presented, which is based on the Lagrangian sampling scheme, but extended to account for precise transport velocities and mixing along river stretches. The calculated mass balances allow accurate quantification of pollutants' reactivity along river segments. This is demonstrated for representative members of important groups of micropollutants, e.g. pharmaceuticals, musk fragrances, flame retardants, and pesticides. A model-aided analysis of the measured data series gives insight into the temporal dynamics of removal processes. The occurrence of different removal mechanisms such as photooxidation, microbial degradation, and volatilization is discussed. The results demonstrate, that removal processes are highly variable in time and space and this has to be considered for future studies. The high precision sampling scheme presented could be a powerful tool for quantifying removal processes under different boundary conditions and in river segments with contrasting properties.

  15. HIGH-PRECISION ASTROMETRIC MILLIMETER VERY LONG BASELINE INTERFEROMETRY USING A NEW METHOD FOR ATMOSPHERIC CALIBRATION

    SciTech Connect

    Rioja, M.; Dodson, R.

    2011-04-15

    We describe a new method which achieves high-precision very long baseline interferometry (VLBI) astrometry in observations at millimeter (mm) wavelengths. It combines fast frequency-switching observations, to correct for the dominant non-dispersive tropospheric fluctuations, with slow source-switching observations, for the remaining ionospheric dispersive terms. We call this method source-frequency phase referencing. Provided that the switching cycles match the properties of the propagation media, one can recover the source astrometry. We present an analytic description of the two-step calibration strategy, along with an error analysis to characterize its performance. Also, we provide observational demonstrations of a successful application with observations using the Very Long Baseline Array at 86 GHz of the pairs of sources 3C274 and 3C273 and 1308+326 and 1308+328 under various conditions. We conclude that this method is widely applicable to mm-VLBI observations of many target sources, and unique in providing bona fide astrometrically registered images and high-precision relative astrometric measurements in mm-VLBI using existing and newly built instruments, including space VLBI.

  16. A high-precision sampling scheme to assess persistence and transport characteristics of micropollutants in rivers.

    PubMed

    Schwientek, Marc; Guillet, Gaëlle; Rügner, Hermann; Kuch, Bertram; Grathwohl, Peter

    2016-01-01

    Increasing numbers of organic micropollutants are emitted into rivers via municipal wastewaters. Due to their persistence many pollutants pass wastewater treatment plants without substantial removal. Transport and fate of pollutants in receiving waters and export to downstream ecosystems is not well understood. In particular, a better knowledge of processes governing their environmental behavior is needed. Although a lot of data are available concerning the ubiquitous presence of micropollutants in rivers, accurate data on transport and removal rates are lacking. In this paper, a mass balance approach is presented, which is based on the Lagrangian sampling scheme, but extended to account for precise transport velocities and mixing along river stretches. The calculated mass balances allow accurate quantification of pollutants' reactivity along river segments. This is demonstrated for representative members of important groups of micropollutants, e.g. pharmaceuticals, musk fragrances, flame retardants, and pesticides. A model-aided analysis of the measured data series gives insight into the temporal dynamics of removal processes. The occurrence of different removal mechanisms such as photooxidation, microbial degradation, and volatilization is discussed. The results demonstrate, that removal processes are highly variable in time and space and this has to be considered for future studies. The high precision sampling scheme presented could be a powerful tool for quantifying removal processes under different boundary conditions and in river segments with contrasting properties. PMID:26283620

  17. Opportunities for High Precision Photometric Measurements of Variable Stars: Kepler Guest Investigator Program

    NASA Astrophysics Data System (ADS)

    Borucki, W. J.; Koch, D. G.; Basri, G. S.; Latham, D. W.; Howell, S. B.

    2004-12-01

    The Kepler Mission is designed to detect terrestrial planets by monitoring the flux of more than 100,000 dwarf stars for a period of four years at a cadence of 4/hour. During the early portion of the mission when the telemetry rate is high, approximately 170,000 stars will be monitored. The photometric precision for 6.5-hour integration periods will be 20 ppm to 89 ppm for 12th to 15th magnitude stars, respectively. Prior to the launch, multiband photometry of all target stars will be made to estimate spectral type, brightness temperature, and luminosity class. To the extent possible, the initial target list will exclude evolved stars and those known to be variable. Sometime after the first year, the target list will be trimmed by removing those stars found to be too variable to detect planets unless requests for continued observations are received from the stellar astrophysics community. A Guest Observer program is being developed to accommodate those wishing to observe targets in the 140 square degree Kepler field of view centered at RA 19h 22m 40s, Dec +44° 30'. A webtool is available to assess whether your favorite object is on the Kepler detectors. This program represents an unprecedented opportunity to obtain extremely high precision photometry over very long (typically 3 month) intervals with almost continuous coverage. At any given time there will be 2000-3000 Guest Observer targets (a few of which can be observed with a one-minute cadence).

  18. Aspects of ultra-high-precision diamond machining of RSA 443 optical aluminium

    NASA Astrophysics Data System (ADS)

    Mkoko, Z.; Abou-El-Hossein, K.

    2015-08-01

    Optical aluminium alloys such as 6061-T6 are traditionally used in ultra-high precision manufacturing for making optical mirrors for aerospace and other applications. However, the optics industry has recently witnessed the development of more advanced optical aluminium grades that are capable of addressing some of the issues encountered when turning with single-point natural monocrystalline diamond cutters. The advent of rapidly solidified aluminium (RSA) grades has generally opened up new possibilities for ultra-high precision manufacturing of optical components. In this study, experiments were conducted with single-point diamond cutters on rapidly solidified aluminium RSA 443 material. The objective of this study is to observe the effects of depth of cut and feed rate at a fixed rotational speed on the tool wear rate and resulting surface roughness of diamond turned specimens. This is done to gain further understanding of the rate of wear on the diamond cutters versus the surface texture generated on the RSA 443 material. The diamond machining experiments yielded machined surfaces which are less reflective but with consistent surface roughness values. Cutting tools were observed for wear through scanning microscopy; relatively low wear pattern was evident on the diamond tool edge. The highest tool wear were obtained at higher depth of cut and increased feed rate.

  19. A high precision position sensor design and its signal processing algorithm for a maglev train.

    PubMed

    Xue, Song; Long, Zhiqiang; He, Ning; Chang, Wensen

    2012-01-01

    High precision positioning technology for a kind of high speed maglev train with an electromagnetic suspension (EMS) system is studied. At first, the basic structure and functions of the position sensor are introduced and some key techniques to enhance the positioning precision are designed. Then, in order to further improve the positioning signal quality and the fault-tolerant ability of the sensor, a new kind of discrete-time tracking differentiator (TD) is proposed based on nonlinear optimal control theory. This new TD has good filtering and differentiating performances and a small calculation load. It is suitable for real-time signal processing. The stability, convergence property and frequency characteristics of the TD are studied and analyzed thoroughly. The delay constant of the TD is figured out and an effective time delay compensation algorithm is proposed. Based on the TD technology, a filtering process is introduced in to improve the positioning signal waveform when the sensor is under bad working conditions, and a two-sensor switching algorithm is designed to eliminate the positioning errors caused by the joint gaps of the long stator. The effectiveness and stability of the sensor and its signal processing algorithms are proved by the experiments on a test train during a long-term test run.

  20. Study of highly precise outdoor characterization technique for photovoltaic modules in terms of reproducibility

    NASA Astrophysics Data System (ADS)

    Fukabori, Akihiro; Takenouchi, Takakazu; Matsuda, Youji; Tsuno, Yuki; Hishikawa, Yoshihiro

    2015-08-01

    In this study, novel outdoor measurements were conducted for highly precise characterization of photovoltaic (PV) modules by measuring current-voltage (I-V) curves with fast sweep speeds and module’s temperature, and with a PV sensor for reference. Fast sweep speeds suppressed the irradiance variation. As a result, smooth I-V curves were obtained and the PV parameter deviation was suppressed. The module’s temperature was measured by attaching resistive temperature detector sensors on the module’s backsheet. The PV sensor was measured synchronously with the PV module. The PV parameters including Isc, Pmax, Voc, and FF were estimated after correcting the I-V curves using the IEC standards. The reproducibility of Isc, Pmax, Voc, and FF relative to the outdoor fits was evaluated as 0.43, 0.58, 0.24, and 0.23%, respectively. The results demonstrate that highly precise measurements are possible using a PV measurement system with the three above-mentioned features.

  1. Diode Laser-based Sensor for High Precision Measurements of Ambient CO2

    NASA Astrophysics Data System (ADS)

    Sonnenfroh, D. M.; Parameswaran, K.; Varner, R.

    2008-12-01

    We report on the development of a new, high precision sensor for monitoring ambient CO2. This economical, robust, autonomous CO2 sensor is intended for widespread deployment in networks. We have developed a tunable diode laser-based absorption spectrometer, operating at a wavelength of 2 "Ým, which utilizes Integrated Cavity Output Spectroscopy (ICOS) to create an optical pathlength of 60 m in a physical pathlength of 20 cm. The sensor also uses Wavelength Modulation Spectroscopy for high sensitivity detection. We have achieved a precision of better than 1 part in 3000 for the dry air mixing ratio of CO2 for a 1 minute averaging period. The sensor design ensures a measurement cell having a small sample volume, which decreases the consumption of calibration gases. We also use an integrated dedicated microprocessor-based controller and signal processing electronics to achieve a small footprint. The sensor measures 20 x 43 x 56 cm and weighs 15 kg. The prototype was demonstrated at the University of New Hampshire's Atmospheric Observatory at Thompson Farm, in Durham, NH during June and July 2008. It was successfully intercompared with an NDIR sensor and operated automatically around the clock for 6 weeks. It was also intercompared with the NOAA NDIR sensor at the Boulder Atmospheric Observatory in Erie, CO in September 2008.

  2. High-precision temporal constraints on intrusive magmatism of the Siberian Traps

    NASA Astrophysics Data System (ADS)

    Burgess, Seth; Bowring, Sam; Pavlov, Volodia E.; Veselovsky, Roman V.

    2014-05-01

    The broad temporal coincidence between large igneous province magmatism and some of the most severe biotic/environmental crises in Earth history has led many to infer a causal connection between the two. Notable examples include the end-Permian mass extinction and eruption/emplacement of the Siberian Traps large igneous province (LIP) and the end-Triassic mass extinction and the Central Atlantic Magmatic Province. In models proposing a causal connection between LIP magmatism and the environmental changes that lead to mass extinction, gases and particulates injected into the atmosphere are thought to cause abrupt changes in climate and ocean chemistry sufficient to drive mass extinction of marine and terrestrial biota. Magmatism has been proposed to cause voluminous volatile release via contact metamorphism of the sedimentary rocks. In the case of the Siberian Traps LIP, the compositions of sedimentary rocks (carbonates, evaporates, organic-rich shales) that host sills and dikes are ideal for greenhouse gas generation. When coupled with the enormous volume of Siberian LIP intrusive rocks, there is the potential for volatile generation on a scale necessary to drive environmental changes and mass extinction. This model must be tested by comparing the timing of intrusive magmatism with that of the mass extinction. Coupled high-precision geochronology and astrochronology have constrained the timing of biotic crisis and associated environmental perturbations from the deca-millennial to sub-millennial timescale, suggesting that the biotic crisis was abrupt, occurring over < 100 ka. Published geochronology on sills and dikes from the LIP are sparse and lack the necessary precision to resolve the relative timing of the two events outside of age uncertainty. We present new high-precision U-Pb zircon geochronology on seventeen gabbroic sills from throughout the magmatic province. This includes samples from the mineralized and differentiated intrusions in the Noril'sk region

  3. Precision-cut liver slices to investigate responsiveness of deep-sea fish to contaminants at high pressure.

    PubMed

    Lemaire, Benjamin; Debier, Cathy; Calderon, Pedro Buc; Thomé, Jean Pierre; Stegeman, John; Mork, Jarle; Rees, Jean François

    2012-09-18

    While deep-sea fish accumulate high levels of persistent organic pollutants (POPs), the toxicity associated with this contamination remains unknown. Indeed, the recurrent collection of moribund individuals precludes experimental studies to investigate POP effects in this fauna. We show that precision-cut liver slices (PCLS), an in vitro tool commonly used in human and rodent toxicology, can overcome such limitation. This technology was applied to individuals of the deep-sea grenadier Coryphaenoides rupestris directly upon retrieval from 530-m depth in Trondheimsfjord (Norway). PCLS remained viable and functional for 15 h when maintained in an appropriate culture media at 4 °C. This allowed experimental exposure of liver slices to the model POP 3-methylcholanthrene (3-MC; 25 μM) at levels of hydrostatic pressure mimicking shallow (0.1 megapascal or MPa) and deep-sea (5-15 MPa; representative of 500-1500 m depth) environments. As in shallow water fish, 3-MC induced the transcription of the detoxification enzyme cytochrome P4501A (CYP1A; a biomarker of exposure to POPs). This induction was diminished at elevated pressure, suggesting a limited responsiveness of C. rupestris toward POPs in its native environment. This very first in vitro toxicological investigation on a deep-sea fish opens the route for understanding pollutants effects in this highly exposed fauna. PMID:22900608

  4. High-precise DEM Generation Using Envisat/ERS-2 Cross-interferometry

    NASA Astrophysics Data System (ADS)

    Lee, W.; Jung, H.; Lu, Z.; Zhang, L.

    2010-12-01

    Cross-interferometric synthetic aperture radar (CInSAR) technique from ERS-2 and Envisat images is capable of generating submeter-accuracy digital elevation model (DEM). However, it is very difficult to produce high-quality CInSAR-derived DEM due to the difference in the azimuth and range pixel size between ERS-2 and Envisat images as well as the small height ambiguity of CInSAR interferogram. In this study, we have proposed an efficient method to overcome the problems, produced a high-quality DEM over northern Alaska, and assessed the accuracy of the CInSAR-derived DEM with an airborne InSAR-derived DEM, which has the spatial resolution of 5 meters, from U.S. Geological Survey. In the proposed method, azimuth common band filtering in the radar raw data processing and DEM-assisted SAR coregistration are applied to mitigate the mis-registration due to the difference in the azimuth and range pixel size and large baseline, and differential SAR interferogram (DInSAR) created by using the low-quality DEM is used for reducing the unwrapping error occurred by the high fringe rate of CInSAR interferogram. From accuracy assessment, in flat area, the precision of CInSAR-derived DEM was approximately 4.2 m and 70cm in the horizontal and vertical directions, respectively, and the ground resolution estimated by the wave number analysis was about 15m. However, most errors occurred in around water area (like lake). And generating time is different between Airborne DEM (July, 2002) and CInSAR DEM(January, 2008). Focus on land area (not around water), vertical accuracy is highly improved about submeter unit. Our results indicate that high-precise DEM of submeter-accuracy can be generated by the proposed method.

  5. Non-contact profiling for high precision fast asphere topology measurement

    NASA Astrophysics Data System (ADS)

    Petter, Jürgen; Berger, Gernot

    2013-04-01

    Quality control in the fabrication of high precision optics these days needs nanometer accuracy. However, the fast growing number of optics with complex aspheric shapes demands an adapted measurement method as existing metrology systems more and more reach their limits. In this contribution the authors present a unique and highly flexible approach for measuring spheric and aspheric optics with diameters from 2mm up to 420mm and with almost unlimited spheric departures. Based on a scanning point interferometer the system combines the high precision and the speed of an optical interferometer with the high form flexibility of a classical tactile scanning system. This enables the measurement of objects with steep or strongly changing slopes such as "pancake" or "gull wing" objects. The high accuracy of ±50nm over the whole surface is achieved by using a full reference concept ensuring the position control even over long scanning paths. The core of the technology is a multiwavelength interferometer (MWLI); by use of several wavelengths this sensor system allows for the measurement of objects with polished as well as with ground surfaces. Furthermore, a large absolute measurement range facilitates measuring surfaces with steps or discontinuities like diffractive structures or even segmented objects. As all the measurements can be done using one and the same system, a direct comparison is possible during production and after finishing an object. The contribution gives an insight into the functionality of the MWLI-sensor as well as into the concept of the reference system of the scanning metrology system. Furthermore, samples of application are discussed.

  6. A demonstration of high precision GPS orbit determination for geodetic applications

    NASA Technical Reports Server (NTRS)

    Lichten, S. M.; Border, J. S.

    1987-01-01

    High precision orbit determination of Global Positioning System (GPS) satellites is a key requirement for GPS-based precise geodetic measurements and precise low-earth orbiter tracking, currently under study at JPL. Different strategies for orbit determination have been explored at JPL with data from a 1985 GPS field experiment. The most successful strategy uses multi-day arcs for orbit determination and includes fine tuning of spacecraft solar pressure coefficients and station zenith tropospheric delays using the GPS data. Average rms orbit repeatability values for 5 of the GPS satellites are 1.0, 1.2, and 1.7 m in altitude, cross-track, and down-track componenets when two independent 5-day fits are compared. Orbit predictions up to 24 hours outside the multi-day arcs agree within 4 m of independent solutions obtained with well tracked satellites in the prediction interval. Baseline repeatability improves with multi-day as compared to single-day arc orbit solutions. When tropospheric delay fluctuations are modeled with process noise, significant additional improvement in baseline repeatability is achieved. For a 246-km baseline, with 6-day arc solutions for GPS orbits, baseline repeatability is 2 parts in 100 million (0.4-0.6 cm) for east, north, and length components and 8 parts in 100 million for the vertical component. For 1314 and 1509 km baselines with the same orbits, baseline repeatability is 2 parts in 100 million for the north components (2-3 cm) and 4 parts in 100 million or better for east, length, and vertical components.

  7. Development of a High Precision and Stability Ambient N2O and CO Analyzer

    NASA Astrophysics Data System (ADS)

    Zhou, Jingang; Hoffnagle, John; Tan, Sze; Dong, Feng; Fleck, Derek; Yiu, John; Huang, Kuan; Leggett, Graham; He, Yonggang

    2016-04-01

    With a global warming potential of nearly 300, N2O is a critically important greenhouse gas, contributing about 5 % of the US total GHG emissions. Agriculture soil management practices are the dominant source of anthropogenic N2O emissions, contributing nearly 75 % of US N2O emissions. In urban areas, vehicle tailpipe emissions and waste water treatment plants are significant sources of N2O. We report here a new mid-infrared laser-based cavity ring-down spectrometer (Picarro G5310) that was recently developed to simultaneously measure sub-ppb ambient concentrations of two key greenhouse gas species, N2O and CO, while measuring H2O as well. It combines a quantum cascade laser with a proprietary 3-mirror optical cavity. The ambient N2O and CO measurement precisions are 0.1ppb (10sec), 0.014ppb (600sec), and 0.006ppb (3000sec); and the measurements could even be averaged down over 3 hours, giving measurement precisions of 0.003ppb. The measurable N2O and CO ranges have been tested up to 2.5ppm. With the high precision and unparalleled stability, G5310 is believed a promising tool for long-term monitoring in atmospheric sciences. The new optical analyzer was set up to monitor N2O and CO (G5310), along with CO2 and CH4(G4301), in ambient air obtained from a 10 meter tower in Santa Clara, California. Evidence of contributions from traffic and a nearby sewage treatment facility were expected in the measurement data.

  8. Highly precise and developmentally programmed genome assembly in Paramecium requires ligase IV-dependent end joining.

    PubMed

    Kapusta, Aurélie; Matsuda, Atsushi; Marmignon, Antoine; Ku, Michael; Silve, Aude; Meyer, Eric; Forney, James D; Malinsky, Sophie; Bétermier, Mireille

    2011-04-01

    During the sexual cycle of the ciliate Paramecium, assembly of the somatic genome includes the precise excision of tens of thousands of short, non-coding germline sequences (Internal Eliminated Sequences or IESs), each one flanked by two TA dinucleotides. It has been reported previously that these genome rearrangements are initiated by the introduction of developmentally programmed DNA double-strand breaks (DSBs), which depend on the domesticated transposase PiggyMac. These DSBs all exhibit a characteristic geometry, with 4-base 5' overhangs centered on the conserved TA, and may readily align and undergo ligation with minimal processing. However, the molecular steps and actors involved in the final and precise assembly of somatic genes have remained unknown. We demonstrate here that Ligase IV and Xrcc4p, core components of the non-homologous end-joining pathway (NHEJ), are required both for the repair of IES excision sites and for the circularization of excised IESs. The transcription of LIG4 and XRCC4 is induced early during the sexual cycle and a Lig4p-GFP fusion protein accumulates in the developing somatic nucleus by the time IES excision takes place. RNAi-mediated silencing of either gene results in the persistence of free broken DNA ends, apparently protected against extensive resection. At the nucleotide level, controlled removal of the 5'-terminal nucleotide occurs normally in LIG4-silenced cells, while nucleotide addition to the 3' ends of the breaks is blocked, together with the final joining step, indicative of a coupling between NHEJ polymerase and ligase activities. Taken together, our data indicate that IES excision is a "cut-and-close" mechanism, which involves the introduction of initiating double-strand cleavages at both ends of each IES, followed by DSB repair via highly precise end joining. This work broadens our current view on how the cellular NHEJ pathway has cooperated with domesticated transposases for the emergence of new mechanisms

  9. Novel fiber Bragg grating fabrication method by high-precision shutter control

    NASA Astrophysics Data System (ADS)

    Liu, Yisi; Gu, Claire; Pan, J. J.; Dong, Liang; Zhou, Feng Q.

    2003-10-01

    Fiber Bragg grating (FBG) is an important element in many applications including filters and dispersion compensators in fiber communication systems. With recently developed inverse scattering algorithm, FBGs with desired reflection spectrum and/or dispersion properties can now be designed. However, most of these designs require arbitrary grating amplitude and phase control. Previously, fabrication of such FBGs relies on the accurate control of the temporal variation of the intensity pattern using a piezo electric translation stage. The precision of this fabrication method is limited by the noise in the control voltage, which is usually larger than 1%. The distortion in piezo response also affects the performance. In this paper, we develop and demonstrate a novel writing technique for arbitrary FBG fabrication. Our technique is based on a translate-and-write configuration. The incorporation of a precisely controlled shutter allows the apodization and phase of the FBG to be continuously changed at each grating line. The shutter error mainly results from the control signal's timing jitter, which is normally lower than 0.1%. Using this writing technique, we demonstrate a Hamming apodized grating with 20mm length, -22 dB minimum transmission, and < -25 dB reflection side lobe suppression. Furthermore, phase-shift in a grating can be fabricated by a simple delay in the control signal. We also demonstrate FBGs with π, π/2, 3π/2 phase-shifts, respectively. Our experimental results are in excellent agreement with theoretical predictions. To show the capability to fabricate a FBG with arbitrary structure, we demonstrate a 35 mm long zero dispersion grating.

  10. Versatile, kinetically controlled, high precision electrohydrodynamic writing of micro/nanofibers

    PubMed Central

    Huang, YongAn; Duan, Yongqing; Ding, Yajiang; Bu, Ningbin; Pan, Yanqiao; Lu, Nanshu; Yin, Zhouping

    2014-01-01

    Direct writing of hierarchical micro/nanofibers have recently gained popularity in flexible/stretchable electronics due to its low cost, simple process and high throughput. A kinetically controlled mechanoelectrospinning (MES) is developed to directly write diversified hierarchical micro/nanofibers in a continuous and programmable manner. Unlike conventional near-field electrospinning, our MES method introduces a mechanical drawing force, to simultaneously enhance the positioning accuracy and morphology controllability. The MES is predominantly controlled by the substrate speed, the nozzle-to-substrate distance, and the applied voltage. As a demonstration, smooth straight, serpentine, self-similar, and bead-on-string structures are direct-written on silicon/elastomer substrates with a resolution of 200 nm. It is believed that MES can promote the low-cost, high precision fabrication of flexible/stretchable electronics or enable the direct writing of the sacrificial structures for nanoscale lithography. PMID:25091829

  11. Flow-Based Systems for Rapid and High-Precision Enzyme Kinetics Studies

    PubMed Central

    Hartwell, Supaporn Kradtap; Grudpan, Kate

    2012-01-01

    Enzyme kinetics studies normally focus on the initial rate of enzymatic reaction. However, the manual operation of steps of the conventional enzyme kinetics method has some drawbacks. Errors can result from the imprecise time control and time necessary for manual changing the reaction cuvettes into and out of the detector. By using the automatic flow-based analytical systems, enzyme kinetics studies can be carried out at real-time initial rate avoiding the potential errors inherent in manual operation. Flow-based systems have been developed to provide rapid, low-volume, and high-precision analyses that effectively replace the many tedious and high volume requirements of conventional wet chemistry analyses. This article presents various arrangements of flow-based techniques and their potential use in future enzyme kinetics applications. PMID:22577614

  12. High precision tune and coupling measurements and tune/coupling feedback in RHIC

    SciTech Connect

    Minty, M.; Curcio, A.; Dawson, C.; Degen, C.; Luo, Y.; Marr, G.; Martin, B.; Marusic, A.; Mernick, K.; Oddo, P.; Russo, T.; Schoefer, V.; Schroeder, R.; Schulthiess, C.; Wilinski, M.

    2010-08-01

    Precision measurement and control of the betatron tunes and betatron coupling in RHIC are required for establishing and maintaining both good operating conditions and, particularly during the ramp to high beam energies, high proton beam polarization. While the proof-of-principle for simultaneous tune and coupling feedback was successfully demonstrated earlier, routine application of these systems has only become possible recently. Following numerous modifications for improved measurement resolution and feedback control, the time required to establish full-energy beams with the betatron tunes and coupling regulated by feedback was reduced from several weeks to a few hours. A summary of these improvements, select measurements benefitting from the improved resolution and a review of system performance are the subject of this report.

  13. Versatile, kinetically controlled, high precision electrohydrodynamic writing of micro/nanofibers.

    PubMed

    Huang, YongAn; Duan, Yongqing; Ding, Yajiang; Bu, Ningbin; Pan, Yanqiao; Lu, Nanshu; Yin, Zhouping

    2014-08-05

    Direct writing of hierarchical micro/nanofibers have recently gained popularity in flexible/stretchable electronics due to its low cost, simple process and high throughput. A kinetically controlled mechanoelectrospinning (MES) is developed to directly write diversified hierarchical micro/nanofibers in a continuous and programmable manner. Unlike conventional near-field electrospinning, our MES method introduces a mechanical drawing force, to simultaneously enhance the positioning accuracy and morphology controllability. The MES is predominantly controlled by the substrate speed, the nozzle-to-substrate distance, and the applied voltage. As a demonstration, smooth straight, serpentine, self-similar, and bead-on-string structures are direct-written on silicon/elastomer substrates with a resolution of 200 nm. It is believed that MES can promote the low-cost, high precision fabrication of flexible/stretchable electronics or enable the direct writing of the sacrificial structures for nanoscale lithography.

  14. Note: high precision angle generator using multiple ultrasonic motors and a self-calibratable encoder.

    PubMed

    Kim, Jong-Ahn; Kim, Jae Wan; Kang, Chu-Shik; Jin, Jonghan; Eom, Tae Bong

    2011-11-01

    We present an angle generator with high resolution and accuracy, which uses multiple ultrasonic motors and a self-calibratable encoder. A cylindrical air bearing guides a rotational motion, and the ultrasonic motors achieve high resolution over the full circle range with a simple configuration. The self-calibratable encoder can compensate the scale error of a divided circle (signal period: 20") effectively by applying the equal-division-averaged method. The angle generator configures a position feedback control loop using the readout of the encoder. By combining the ac and dc operation mode, the angle generator produced stepwise angular motion with 0.005" resolution. We also evaluated the performance of the angle generator using a precision angle encoder and an autocollimator. The expanded uncertainty (k = 2) in the angle generation was estimated less than 0.03", which included the calibrated scale error and the nonlinearity error.

  15. High-precision optomechanical lens system for space applications assembled by a local soldering technique

    NASA Astrophysics Data System (ADS)

    Pleguezuelo, Pol Ribes; Koechlin, Charlie; Hornaff, Marcel; Kamm, Andreas; Beckert, Erik; Fiault, Guillaume; Eberhardt, Ramona; Tünnermann, Andreas

    2016-06-01

    Soldering using metallic solder alloys is an alternative to adhesive bonding. Laser-based soldering processes are especially well suited for the joining of optical components made of fragile and brittle materials such as glass, ceramics, and optical crystals. This is due to a localized and minimized input of thermal energy. Solderjet bumping technology has been used to assemble a lens mount breadboard using specifications and requirements found for the optical beam expander for the European Space Agency EarthCare Mission. The silica lens and a titanium barrel have been designed and assembled with this technology in order to withstand the stringent mission demands of handling high mechanical and thermal loads without losing the optical performance. Finally, a high-precision optomechanical lens mount has been assembled with minimal localized stress (<1 MPa) showing outstanding performance in terms of wave-front error and beam depolarization ratio before and after environmental tests.

  16. End of Frustration: Catalytic Precision Polymerization with Highly Interacting Lewis Pairs.

    PubMed

    Knaus, Maximilian G M; Giuman, Marco M; Pöthig, Alexander; Rieger, Bernhard

    2016-06-22

    Herein we report on the catalytic polymerization of diverse Michael-type monomers with high precision by using simple but highly active combinations of phosphorus-containing Lewis bases and organoaluminum compounds. The interacting Lewis pair catalysts enable the control of molecular weight and microstructure of the produced polymers. The reactions show a linear Mn vs consumption plot thus proving a living type polymerization. The initiation has been investigated by end-group analysis with ESI mass spectrometric analysis. With these main-group element Lewis acid base pairs, it is not only possible to polymerize sterically demanding, functionalized as well as heteroatom containing monomers but also, for the first time, to catalytically polymerize extended Michael systems, like 4-vinylpyridine. PMID:27254134

  17. Versatile, kinetically controlled, high precision electrohydrodynamic writing of micro/nanofibers

    NASA Astrophysics Data System (ADS)

    Huang, Yongan; Duan, Yongqing; Ding, Yajiang; Bu, Ningbin; Pan, Yanqiao; Lu, Nanshu; Yin, Zhouping

    2014-08-01

    Direct writing of hierarchical micro/nanofibers have recently gained popularity in flexible/stretchable electronics due to its low cost, simple process and high throughput. A kinetically controlled mechanoelectrospinning (MES) is developed to directly write diversified hierarchical micro/nanofibers in a continuous and programmable manner. Unlike conventional near-field electrospinning, our MES method introduces a mechanical drawing force, to simultaneously enhance the positioning accuracy and morphology controllability. The MES is predominantly controlled by the substrate speed, the nozzle-to-substrate distance, and the applied voltage. As a demonstration, smooth straight, serpentine, self-similar, and bead-on-string structures are direct-written on silicon/elastomer substrates with a resolution of 200 nm. It is believed that MES can promote the low-cost, high precision fabrication of flexible/stretchable electronics or enable the direct writing of the sacrificial structures for nanoscale lithography.

  18. High precision mapping of kidney stones using μ-IR spectroscopy to determine urinary lithogenesis.

    PubMed

    Blanco, Francisco; Ortiz-Alías, Pilar; López-Mesas, Montserrat; Valiente, Manuel

    2015-06-01

    Evolution of urinary lithiasis is determined by the metabolism and life-style of the related patient. The appropriate classification of the stone is mandatory for the identification of the lithogenic process. In this study, cros-sections from a single stone of each of the most frequent urolithiasis types (calcium oxalate mono and dihydrate and carbonate apatite) have been selected and imaged using IR microspectroscopy. Moreover, the use of high definition sFTIR (synchrotron source) has revealed hidden information to the conventional FTIR. This work has demonstrated that minor components become key factors on the description of the stages of stone formation. Intensity map for COM (1630 cm(-1) peak). The high spatial definition achieved is key for the precise description of the kidney stone history.

  19. High Precision Tune and Coupling Feedback and Beam Transfer Function Measurements in RHIC

    SciTech Connect

    Minty, M.; Curcio, A.; Dawson, C.; Degen, C.; Luo, Y.; Marr, G.; Martin, B.; Marusic, A.; Mernick, K.; Oddo, P.; Russo, T.; Schoefer, V.; Schroeder, R.; Schultheiss, C.; Wilinski, M.

    2010-05-23

    Precision measurement and control of the betatron tunes and betatron coupling in the Relativistic Heavy Ion Collider (RHIC) are required for establishing and maintaining both good operating conditions and, particularly during the ramp to high beam energies, high proton beam polarization. While the proof-of-principle for simultaneous tune and coupling feedback was successfully demonstrated earlier, routine application of these systems has only become possible recently. Following numerous modifications for improved measurement resolution and feedback control, the time required to establish full-energy beams with the betatron tunes and coupling regulated by feedback was reduced from several weeks to a few hours. A summary of these improvements, select measurements benefitting from the improved resolution and a review of system performance are the subject of this report.

  20. Precision high-value resistance scaling with a two-terminal cryogenic current comparator

    NASA Astrophysics Data System (ADS)

    Hernandez-Marquez, F. L.; Bierzychudek, M. E.; Jones, G. R.; Elmquist, R. E.

    2014-04-01

    We describe a cryogenic two-terminal high-resistance bridge and its application in precision resistance scaling from the quantized Hall resistance (QHR) at RH = RK/2 = 12 906.4035 Ω to decade resistance standards with values between 1 MΩ and 1 GΩ. The design minimizes lead resistance errors with multiterminal connections to the QHR device. A single variable voltage source and resistive ratio windings are utilized to achieve excellent dynamic stability, which is not readily obtained in low-current measurements with conventional cryogenic current comparators (CCCs). Prototypes of this bridge have been verified by a successful international comparison of high-resistance scaling using two-terminal CCCs in the national metrology institutes of Argentina, Mexico, and the United States.

  1. Design and characteristics of a high-precision chopper wheel motor driver

    SciTech Connect

    Gu Xibin; Guo Ying; Chan, Henry; Kawamura, Ed; Kaiser, Ralf I.

    2005-11-15

    The circuit diagram and design principles of a high-stability chopper wheel motor driver are presented. Experimental results show that this unit can be interfaced to molecular-beam machines to generate supersonic beams with extremely stable root-mean-square and peak velocities fluctuating on a day-to-day basis by less than 0.2%.

  2. High-precision GPS autonomous platforms for sea ice dynamics and physical oceanography

    NASA Astrophysics Data System (ADS)

    Elosegui, P.; Wilkinson, J.; Olsson, M.; Rodwell, S.; James, A.; Hagan, B.; Hwang, B.; Forsberg, R.; Gerdes, R.; Johannessen, J.; Wadhams, P.; Nettles, M.; Padman, L.

    2012-12-01

    Project "Arctic Ocean sea ice and ocean circulation using satellite methods" (SATICE), is the first high-rate, high-precision, continuous GPS positioning experiment on sea ice in the Arctic Ocean. The SATICE systems collect continuous, dual-frequency carrier-phase GPS data while drifting on sea ice. Additional geophysical measurements also collected include ocean water pressure, ocean surface salinity, atmospheric pressure, snow-depth, air-ice-ocean temperature profiles, photographic imagery, and others, enabling sea ice drift, freeboard, weather, ice mass balance, and sea-level height determination. Relatively large volumes of data from each buoy are streamed over a satellite link to a central computer on the Internet in near real time, where they are processed to estimate the time-varying buoy positions. SATICE system obtains continuous GPS data at sub-minute intervals with a positioning precision of a few centimetres in all three dimensions. Although monitoring of sea ice motions goes back to the early days of satellite observations, these autonomous platforms bring out a level of spatio-temporal detail that has never been seen before, especially in the vertical axis. These high-resolution data allows us to address new polar science questions and challenge our present understanding of both sea ice dynamics and Arctic oceanography. We will describe the technology behind this new autonomous platform, which could also be adapted to other applications that require high resolution positioning information with sustained operations and observations in the polar marine environment, and present results pertaining to sea ice dynamics and physical oceanography.

  3. A Lightweight, Precision-Deployable, Optical Bench for High Energy Astrophysics Missions

    NASA Astrophysics Data System (ADS)

    Danner, Rolf; Dailey, D.; Lillie, C.

    2011-09-01

    The small angle of total reflection for X-rays, forcing grazing incidence optics with large collecting areas to long focal lengths, has been a fundamental barrier to the advancement of high-energy astrophysics. Design teams around the world have long recognized that a significant increase in effective area beyond Chandra and XMM-Newton requires either a deployable optical bench or separate X-ray optics and instrument module on formation flying spacecraft. Here, we show that we have in hand the components for a lightweight, precision-deployable optical bench that, through its inherent design features, is the affordable path to the next generation of imaging high-energy astrophysics missions. We present our plans for a full-scale engineering model of a deployable optical bench for Explorer-class missions. We intend to use this test article to raise the technology readiness level (TRL) of the tensegrity truss for a lightweight, precision-deployable optical bench for high-energy astrophysics missions from TRL 3 to TRL 5 through a set of four well-defined technology milestones. The milestones cover the architecture's ability to deploy and control the focal point, characterize the deployed dynamics, determine long-term stability, and verify the stowed load capability. Our plan is based on detailed design and analysis work and the construction of a first prototype by our team. Building on our prior analysis and the high TRL of the architecture components we are ready to move on to the next step. The key elements to do this affordably are two existing, fully characterized, flight-quality, deployable booms. After integrating them into the test article, we will demonstrate that our architecture meets the deployment accuracy, adjustability, and stability requirements. The same test article can be used to further raise the TRL in the future.

  4. High precision 11B/10B analysis with a simplified MC-ICP-MS

    NASA Astrophysics Data System (ADS)

    Tanimizu, M.; Nagaishi, K.

    2012-04-01

    Boron isotope ratio is a powerful tracer in the fields of geochemistry, biochemistry, and environmental chemistry. One important application of 11B/10B isotope ratio in geochemistry is as an indicator for paleo pH of seawater recorded in marine carbonates in deep-sea sediments. Boron isotope ratios are determined by TIMS or MC-ICP-MS with precisions of better than 0.1 % RSD, but a large inter-lab discrepancy of 0.6 % is still observed for actual carbonate samples (Foster, 2008). Here, we tried to determine B isotope ratio by MC-ICP-MS with a simple and common analytical techniques using a quartz sample introduction system with a PFA nebulizer, and compared to recently developed precise B isotope ratio analysis techniques by TIMS in positive ion detection mode determined as Cs2BO2+ ions with sample amount of <100 ng (Ishikawa and Nagaishi, 2011) and by MC-ICP-MS (Foster, 2008, Louvat et al., 2011). 11B/10B isotope ratios of a 50 ppb B solution dissolved in a HNO3, mannitol, HF-mixed solution were determined against an isotopic reference NIST-SRM 951 with a standard sample bracketing technique in the wet plasma condition. Resultant analytical reproducibility (twice standard deviation) was +/-0.02 % with a consumption of 50 ng B, and the washout time was comparable to that of NH3 gas addition to the introduction system (Foster, 2008). 11B/10B isotope ratios of actual carbonate sample and seawater were determined after simple chemical purification with a common cation exchange resin instead of a boron selective resin. Their relative differences from the standard were consistent with those determined by the positive TIMS within analytical uncertainty. Current potential of MC-ICP-MS for precise B isotopic analysis will be discussed. Foster, G., 2008. Seawater pH, pCO2 and [CO32-] variations in the Caribbean Sea over the last 130kyr: A boron isotope and B/Ca study of planktic foraminifera, Earth Planet. Sci. Lett., 271, 254-266. Ishikawa, T. and Nagaishi, K., 2011. High-precision

  5. High-precision radiocarbon dating and historical biblical archaeology in southern Jordan.

    PubMed

    Levy, Thomas E; Higham, Thomas; Bronk Ramsey, Christopher; Smith, Neil G; Ben-Yosef, Erez; Robinson, Mark; Münger, Stefan; Knabb, Kyle; Schulze, Jürgen P; Najjar, Mohammad; Tauxe, Lisa

    2008-10-28

    Recent excavations and high-precision radiocarbon dating from the largest Iron Age (IA, ca. 1200-500 BCE) copper production center in the southern Levant demonstrate major smelting activities in the region of biblical Edom (southern Jordan) during the 10th and 9th centuries BCE. Stratified radiocarbon samples and artifacts were recorded with precise digital surveying tools linked to a geographic information system developed to control on-site spatial analyses of archaeological finds and model data with innovative visualization tools. The new radiocarbon dates push back by 2 centuries the accepted IA chronology of Edom. Data from Khirbat en-Nahas, and the nearby site of Rujm Hamra Ifdan, demonstrate the centrality of industrial-scale metal production during those centuries traditionally linked closely to political events in Edom's 10th century BCE neighbor ancient Israel. Consequently, the rise of IA Edom is linked to the power vacuum created by the collapse of Late Bronze Age (LB, ca. 1300 BCE) civilizations and the disintegration of the LB Cypriot copper monopoly that dominated the eastern Mediterranean. The methodologies applied to the historical IA archaeology of the Levant have implications for other parts of the world where sacred and historical texts interface with the material record.

  6. High precision study of muon catalyzed fusion in D2 and HD gas

    NASA Astrophysics Data System (ADS)

    Balin, D. V.; Ganzha, V. A.; Kozlov, S. M.; Maev, E. M.; Petrov, G. E.; Soroka, M. A.; Schapkin, G. N.; Semenchuk, G. G.; Trofimov, V. A.; Vasiliev, A. A.; Vorobyov, A. A.; Voropaev, N. I.; Petitjean, C.; Gartner, B.; Lauss, B.; Marton, J.; Zmeskal, J.; Case, T.; Crowe, K. M.; Kammel, P.; Hartmann, F. J.; Faifman, M. P.

    2011-03-01

    Muon catalyzed dd fusion in D2 and HD gases in the temperature range from 28 to 350 K was investigated in a series of experiments based on a time-projection ionization chamber operating with pure hydrogen. All main observables in this reaction chain were measured with high absolute precision including the resonant and non-resonant ddμ formation rates, the rate for hyperfine transitions in dμ atoms, the branching ratio of the two charge symmetric fusion channels 3He + n and t + p and the muon sticking probability. The report presents the final analysis of the data together with a comprehensive comparison with calculations based on recent μCF theories. The energy of the loosely bound ddμ state with quantum numbers J = 1, ν = 1, which is central to the mechanism of resonant molecule formation, is extracted with precision ɛ11(fit) = -1.9651(7) eV. in impressive agreement with the latest theoretical results ɛ11(theory) = -1.9646 eV.

  7. 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.

  8. High-precision correlative fluorescence and electron cryo microscopy using two independent alignment markers☆

    PubMed Central

    Schellenberger, Pascale; Kaufmann, Rainer; Siebert, C. Alistair; Hagen, Christoph; Wodrich, Harald; Grünewald, Kay

    2014-01-01

    Correlative light and electron microscopy (CLEM) is an emerging technique which combines functional information provided by fluorescence microscopy (FM) with the high-resolution structural information of electron microscopy (EM). So far, correlative cryo microscopy of frozen-hydrated samples has not reached better than micrometre range accuracy. Here, a method is presented that enables the correlation between fluorescently tagged proteins and electron cryo tomography (cryoET) data with nanometre range precision. Specifically, thin areas of vitrified whole cells are examined by correlative fluorescence cryo microscopy (cryoFM) and cryoET. Novel aspects of the presented cryoCLEM workflow not only include the implementation of two independent electron dense fluorescent markers to improve the precision of the alignment, but also the ability of obtaining an estimate of the correlation accuracy for each individual object of interest. The correlative workflow from plunge-freezing to cryoET is detailed step-by-step for the example of locating fluorescence-labelled adenovirus particles trafficking inside a cell. PMID:24262358

  9. Two Fabry-Perot interferometers for high precision wavelength calibration in the near-infrared

    NASA Astrophysics Data System (ADS)

    Schäfer, Sebastian; Reiners, Ansgar

    2012-09-01

    The most frequently used standard light sources for spectroscopic high precision wavelength calibration are hollow cathode lamps. These lamps, however, do not provide homogeneous line distribution and intensities. Particularly in the infrared, the number of useful lines is severely limited and the spectrum is contaminated by lines of the filler gas. With the goal of achieving sub m/s stability in the infrared, as required for detecting earthlike extra-solar planets, we are developing two passively stabilized Fabry-Perot interferometers for the red visible (600-1050nm) and near infrared wavelength regions (900-1350nm). Each of the two interferometers can produce ~15,000 lines of nearly constant brightness. The Fabry-Perot interferometers aim at a RV calibration precision of 10cm/s and are optimized in line shape and spacing for the infrared planet hunting CARMENES spectrograph that is currently being built for the Calar Alto 3.5m telescope. Here we present the first results of our work.

  10. Application of the spherical harmonic gravity model in high precision inertial navigation systems

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Yang, Gongliu; Li, Xiangyun; Zhou, Xiao

    2016-09-01

    The spherical harmonic gravity model (SHM) may, in general, be considered as a suitable alternative to the normal gravity model (NGM), because it represents the Earth’s gravitational field more accurately. However, the high-resolution SHM has never been used in current inertial navigation systems (INSs) due to its extremely complex expression. In this paper, the feasibility and accuracy of a truncated SHM are discussed for application in a real-time free-INS with a precision demand better than 0.8 nm h‑1. In particular, the time and space complexity are analyzed mathematically to verify the feasibility of the SHM. Also, a test on a typical navigation computer shows a storable range of cut-off degrees. To further evaluate the appropriate degree and accuracy of the truncated SHM, analyses of covariance and truncation error are proposed. Finally, a SHM of degree 12 is demonstrated to be the appropriate model for routine INSs in the precision range of 0.4–0.75 nm h‑1. Flight simulations and road tests show its outstanding performance over the traditional NGM.

  11. Application of the spherical harmonic gravity model in high precision inertial navigation systems

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Yang, Gongliu; Li, Xiangyun; Zhou, Xiao

    2016-09-01

    The spherical harmonic gravity model (SHM) may, in general, be considered as a suitable alternative to the normal gravity model (NGM), because it represents the Earth’s gravitational field more accurately. However, the high-resolution SHM has never been used in current inertial navigation systems (INSs) due to its extremely complex expression. In this paper, the feasibility and accuracy of a truncated SHM are discussed for application in a real-time free-INS with a precision demand better than 0.8 nm h-1. In particular, the time and space complexity are analyzed mathematically to verify the feasibility of the SHM. Also, a test on a typical navigation computer shows a storable range of cut-off degrees. To further evaluate the appropriate degree and accuracy of the truncated SHM, analyses of covariance and truncation error are proposed. Finally, a SHM of degree 12 is demonstrated to be the appropriate model for routine INSs in the precision range of 0.4-0.75 nm h-1. Flight simulations and road tests show its outstanding performance over the traditional NGM.

  12. High-precision radiocarbon dating and historical biblical archaeology in southern Jordan

    PubMed Central

    Levy, Thomas E.; Higham, Thomas; Bronk Ramsey, Christopher; Smith, Neil G.; Ben-Yosef, Erez; Robinson, Mark; Münger, Stefan; Knabb, Kyle; Schulze, Jürgen P.; Najjar, Mohammad; Tauxe, Lisa

    2008-01-01

    Recent excavations and high-precision radiocarbon dating from the largest Iron Age (IA, ca. 1200–500 BCE) copper production center in the southern Levant demonstrate major smelting activities in the region of biblical Edom (southern Jordan) during the 10th and 9th centuries BCE. Stratified radiocarbon samples and artifacts were recorded with precise digital surveying tools linked to a geographic information system developed to control on-site spatial analyses of archaeological finds and model data with innovative visualization tools. The new radiocarbon dates push back by 2 centuries the accepted IA chronology of Edom. Data from Khirbat en-Nahas, and the nearby site of Rujm Hamra Ifdan, demonstrate the centrality of industrial-scale metal production during those centuries traditionally linked closely to political events in Edom's 10th century BCE neighbor ancient Israel. Consequently, the rise of IA Edom is linked to the power vacuum created by the collapse of Late Bronze Age (LB, ca. 1300 BCE) civilizations and the disintegration of the LB Cypriot copper monopoly that dominated the eastern Mediterranean. The methodologies applied to the historical IA archaeology of the Levant have implications for other parts of the world where sacred and historical texts interface with the material record. PMID:18955702

  13. ARTIFICIAL INCOHERENT SPECKLES ENABLE PRECISION ASTROMETRY AND PHOTOMETRY IN HIGH-CONTRAST IMAGING

    SciTech Connect

    Jovanovic, N.; Guyon, O.; Pathak, P.; Kudo, T.; Martinache, F.; Hagelberg, J.

    2015-11-10

    State-of-the-art coronagraphs employed on extreme adaptive optics enabled instruments are constantly improving the contrast detection limit for companions at ever-closer separations from the host star. In order to constrain their properties and, ultimately, compositions, it is important to precisely determine orbital parameters and contrasts with respect to the stars they orbit. This can be difficult in the post-coronagraphic image plane, as by definition the central star has been occulted by the coronagraph. We demonstrate the flexibility of utilizing the deformable mirror in the adaptive optics system of the Subaru Coronagraphic Extreme Adaptive Optics system to generate a field of speckles for the purposes of calibration. Speckles can be placed up to 22.5 λ/D from the star, with any position angle, brightness, and abundance required. Most importantly, we show that a fast modulation of the added speckle phase, between 0 and π, during a long science integration renders these speckles effectively incoherent with the underlying halo. We quantitatively show for the first time that this incoherence, in turn, increases the robustness and stability of the adaptive speckles, which will improve the precision of astrometric and photometric calibration procedures. This technique will be valuable for high-contrast imaging observations with imagers and integral field spectrographs alike.

  14. A new, high-precision measurement of the X-ray Cu K α spectrum

    NASA Astrophysics Data System (ADS)

    Mendenhall, Marcus H.; Cline, James P.; Henins, Albert; Hudson, Lawrence T.; Szabo, Csilla I.; Windover, Donald

    2016-03-01

    One of the primary measurement issues addressed with NIST Standard Reference Materials (SRMs) for powder diffraction is that of line position. SRMs for this purpose are certified with respect to lattice parameter, traceable to the SI through precise measurement of the emission spectrum of the X-ray source. Therefore, accurate characterization of the emission spectrum is critical to a minimization of the error bounds on the certified parameters. The presently accepted sources for the SI traceable characterization of the Cu K α emission spectrum are those of Härtwig, Hölzer et al., published in the 1990s. The structure of the X-ray emission lines of the Cu K α complex has been remeasured on a newly commissioned double-crystal instrument, with six-bounce Si (440) optics, in a manner directly traceable to the SI definition of the meter. In this measurement, the entire region from 8020 eV to 8100 eV has been covered with a highly precise angular scale and well-defined system efficiency, providing accurate wavelengths and relative intensities. This measurement is in modest disagreement with reference values for the wavelength of the Kα1 line, and strong disagreement for the wavelength of the Kα2 line.

  15. High precision optical cavity length and width measurements using double modulation.

    PubMed

    Staley, A; Hoak, D; Effler, A; Izumi, K; Dwyer, S; Kawabe, K; King, E J; Rakhmanov, M; Savage, R L; Sigg, D

    2015-07-27

    We use doubly phase modulated light to measure both the length and the linewidth of an optical resonator with high precision. The first modulation is at RF frequencies and is set near a multiple of the free spectral range, whereas the second modulation is at audio frequencies to eliminate offset errors at DC. The light in transmission or in reflection of the optical resonator is demodulated while sweeping the RF frequency over the optical resonance. We derive expressions for the demodulated power in transmission, and show that the zero crossings of the demodulated signal in transmission serve as a precise measure of the cavity linewidth at half maximum intensity. We demonstrate the technique on two resonant cavities, with lengths 16 m and a 4 km, and achieve an absolute length accuracy as low as 70 ppb. The cavity width for the 16 m cavity was determined with an accuracy of approximately 6000 ppm. Through an analysis of the systematic errors we show that this result could be substantially improved with the reduction of technical sources of uncertainty. PMID:26367601

  16. Artificial Incoherent Speckles Enable Precision Astrometry and Photometry in High-contrast Imaging

    NASA Astrophysics Data System (ADS)

    Jovanovic, N.; Guyon, O.; Martinache, F.; Pathak, P.; Hagelberg, J.; Kudo, T.

    2015-11-01

    State-of-the-art coronagraphs employed on extreme adaptive optics enabled instruments are constantly improving the contrast detection limit for companions at ever-closer separations from the host star. In order to constrain their properties and, ultimately, compositions, it is important to precisely determine orbital parameters and contrasts with respect to the stars they orbit. This can be difficult in the post-coronagraphic image plane, as by definition the central star has been occulted by the coronagraph. We demonstrate the flexibility of utilizing the deformable mirror in the adaptive optics system of the Subaru Coronagraphic Extreme Adaptive Optics system to generate a field of speckles for the purposes of calibration. Speckles can be placed up to 22.5 λ/D from the star, with any position angle, brightness, and abundance required. Most importantly, we show that a fast modulation of the added speckle phase, between 0 and π, during a long science integration renders these speckles effectively incoherent with the underlying halo. We quantitatively show for the first time that this incoherence, in turn, increases the robustness and stability of the adaptive speckles, which will improve the precision of astrometric and photometric calibration procedures. This technique will be valuable for high-contrast imaging observations with imagers and integral field spectrographs alike.

  17. Three-dimensional microscopic elemental analysis using an automated high-precision serial sectioning system.

    PubMed

    Fujisaki, Kazuhiro; Yokota, Hideo; Furushiro, Naomichi; Komatani, Shintaro; Ohzawa, Sumito; Sato, Yoshimichi; Matsunaga, Daisuke; Himeno, Ryutaro; Higuchi, Toshiro; Makinouchi, Akitake

    2011-04-01

    The elemental composition and microscopic-level shape of inclusions inside industrial materials are considered important factors in fracture analytical studies. In this work, a three-dimensional (3D) microscopic elemental analysis system based on a serial sectioning technique was developed to observe the internal structure of such materials. This 3D elemental mapping system included an X-ray fluorescence analyzer and a high-precision milling machine. Control signals for the X-ray observation process were automatically sent from a data I/O system synchronized with the precision positioning on the milling machine. Composite specimens were used to confirm the resolution and the accuracy of 3D models generated from this system. Each of the two specimens was composed of three metal wires of 0.5 mm diameter braided into a single twisted wire that was placed inside a metal pipe; the pipe was then filled with either epoxy resin or Sn. The milling machine was used to create a mirror-finish cross-sectional surface on these specimens, and elemental analyses were performed. The twisted wire structure was clearly observed in the resulting 3D models. This system enables automated investigation of the 3D internal structure of materials as well as the identification of their elemental components.

  18. Precise color images a high-speed color video camera system with three intensified sensors

    NASA Astrophysics Data System (ADS)

    Oki, Sachio; Yamakawa, Masafumi; Gohda, Susumu; Etoh, Takeharu G.

    1999-06-01

    High speed imaging systems have been used in a large field of science and engineering. Although the high speed camera systems have been improved to high performance, most of their applications are only to get high speed motion pictures. However, in some fields of science and technology, it is useful to get some other information, such as temperature of combustion flame, thermal plasma and molten materials. Recent digital high speed video imaging technology should be able to get such information from those objects. For this purpose, we have already developed a high speed video camera system with three-intensified-sensors and cubic prism image splitter. The maximum frame rate is 40,500 pps (picture per second) at 64 X 64 pixels and 4,500 pps at 256 X 256 pixels with 256 (8 bit) intensity resolution for each pixel. The camera system can store more than 1,000 pictures continuously in solid state memory. In order to get the precise color images from this camera system, we need to develop a digital technique, which consists of a computer program and ancillary instruments, to adjust displacement of images taken from two or three image sensors and to calibrate relationship between incident light intensity and corresponding digital output signals. In this paper, the digital technique for pixel-based displacement adjustment are proposed. Although the displacement of the corresponding circle was more than 8 pixels in original image, the displacement was adjusted within 0.2 pixels at most by this method.

  19. Closed tubes preparation of graphite for high-precision AMS radiocarbon analysis

    NASA Astrophysics Data System (ADS)

    Hajdas, I.; Michczynska, D.; Bonani, G.; Maurer, M.; Wacker, L.

    2009-04-01

    Radiocarbon dating is an established tool applied in Geochronology. Technical developments of Accelerator Mass Spectrometry AMS, which allow measurements of samples containing less than 1 mg of carbon, opened opportunities for new applications. Moreover, high resolution records of the past changes require high-resolution chronologies i.e. sampling for 14C dating. In result, the field of applications is rapidly expanding and number of radiocarbon analysis is growing rapidly. Nowadays dedicated 14C AMS machines have great capacity for analysis but in order to keep up with the demand for analysis and provide the results as fast as possible a very efficient way of sample preparation is required. Sample preparation for 14C AMS analysis consists of two steps: separation of relevant carbon from the sample material (removing contamination) and preparation of graphite for AMS analysis. The last step usually involves reaction of CO2 with H2, in the presence of metal catalyst (Fe or Co) of specific mesh size heated to 550-625°C, as originally suggested by Vogel et al. (1984). Various graphitization systems have been built in order to fulfil the requirement of sample quality needed for high-precision radiocarbon data. In the early 90ties another method has been proposed (Vogel 1992) and applied by few laboratories mainly for environmental or biomedical samples. This method uses TiH2 as a source of H2 and can be easily and flexibly applied to produce graphite. Sample of CO2 is frozen in to the tube containing pre-conditioned Zn/TiH2 and Fe catalyst. Torch sealed tubes are then placed in the stepwise heated oven at 500/550°C and left to react for several hours. The greatest problem is the lack of control of the reaction completeness and considerable fractionation. However, recently reported results (Xu et al. 2007) suggest that high precision dating using graphite produced in closed tubes might be possible. We will present results of radiocarbon dating of the set of standards

  20. High precision series solutions of differential equations: Ordinary and regular singular points of second order ODEs

    NASA Astrophysics Data System (ADS)

    Noreen, Amna; Olaussen, Kåre

    2012-10-01

    A subroutine for a very-high-precision numerical solution of a class of ordinary differential equations is provided. For a given evaluation point and equation parameters the memory requirement scales linearly with precision P, and the number of algebraic operations scales roughly linearly with P when P becomes sufficiently large. We discuss results from extensive tests of the code, and how one, for a given evaluation point and equation parameters, may estimate precision loss and computing time in advance. Program summary Program title: seriesSolveOde1 Catalogue identifier: AEMW_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEMW_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 991 No. of bytes in distributed program, including test data, etc.: 488116 Distribution format: tar.gz Programming language: C++ Computer: PC's or higher performance computers. Operating system: Linux and MacOS RAM: Few to many megabytes (problem dependent). Classification: 2.7, 4.3 External routines: CLN — Class Library for Numbers [1] built with the GNU MP library [2], and GSL — GNU Scientific Library [3] (only for time measurements). Nature of problem: The differential equation -s2({d2}/{dz2}+{1-ν+-ν-}/{z}{d}/{dz}+{ν+ν-}/{z2})ψ(z)+{1}/{z} ∑n=0N vnznψ(z)=0, is solved numerically to very high precision. The evaluation point z and some or all of the equation parameters may be complex numbers; some or all of them may be represented exactly in terms of rational numbers. Solution method: The solution ψ(z), and optionally ψ'(z), is evaluated at the point z by executing the recursion A(z)={s-2}/{(m+1+ν-ν+)(m+1+ν-ν-)} ∑n=0N Vn(z)A(z), ψ(z)=ψ(z)+A(z), to sufficiently large m. Here ν is either ν+ or ν-, and Vn(z)=vnz. The recursion is initialized by A(z)=δzν,for n

  1. An autonomous multisensor in situ metrology system for enabling high dynamic range measurement of 3D surfaces on precision machine tools

    NASA Astrophysics Data System (ADS)

    Liu, Samuel M. Y.; Cheung, Benny C. F.; Whitehouse, David; Cheng, Ching-Hsiang

    2016-11-01

    An in situ measurement is of prime importance when trying to maintain the position of the workpiece for further compensation processes in order to improve the accuracy and efficiency of the precision machining of three dimensional (3D) surfaces. However, the coordinates of most of the machine tools with closed machine interfaces and control system are not accessible for users, which make it difficult to use the motion axes of the machine tool for in situ measurements. This paper presents an autonomous multisensor in situ metrology system for enabling high dynamic range measurement of 3D surfaces on precision machine tools. It makes use of a designed tool path and an additional motion sensor to assist the registration of time-space data for the position estimation of a 2D laser scanner which measures the surface with a high lateral resolution and large area without the need to interface with the machine tool system. A prototype system was built and integrated into an ultra-precision polishing machine. Experimental results show that it measures the 3D surfaces with high resolution, high repeatability, and large measurement range. The system not only improves the efficiency and accuracy of the precision machining process but also extends the capability of machine tools.

  2. Probing active-edge silicon sensors using a high precision telescope

    NASA Astrophysics Data System (ADS)

    Akiba, K.; Artuso, M.; van Beveren, V.; van Beuzekom, M.; Boterenbrood, H.; Buytaert, J.; Collins, P.; Dumps, R.; van der Heijden, B.; Hombach, C.; Hynds, D.; Hsu, D.; John, M.; Koffeman, E.; Leflat, A.; Li, Y.; Longstaff, I.; Morton, A.; Pérez Trigo, E.; Plackett, R.; Reid, M. M.; Rodríguez Perez, P.; Schindler, H.; Tsopelas, P.; Vázquez Sierra, C.; Wysokiński, M.

    2015-03-01

    The performance of prototype active-edge VTT sensors bump-bonded to the Timepix ASIC is presented. Non-irradiated sensors of thicknesses 100-200 μm and pixel-to-edge distances of 50 μm and 100 μm were probed with a beam of charged hadrons with sub-pixel precision using the Timepix telescope assembled at the SPS at CERN. The sensors are shown to be highly efficient up to a few micrometers from the physical edge of the sensor. The distortion of the electric field lines at the edge of the sensors is studied by reconstructing the streamlines of the electric field using two-pixel clusters. These results are supported by TCAD simulations. The reconstructed streamlines are used to study the field distortion as a function of the bias voltage and to apply corrections to the cluster positions at the edge.

  3. Composite-light-pulse technique for high-precision atom interferometry.

    PubMed

    Berg, P; Abend, S; Tackmann, G; Schubert, C; Giese, E; Schleich, W P; Narducci, F A; Ertmer, W; Rasel, E M

    2015-02-13

    We realize beam splitters and mirrors for atom waves by employing a sequence of light pulses rather than individual ones. In this way we can tailor atom interferometers with improved sensitivity and accuracy. We demonstrate our method of composite pulses by creating a symmetric matter-wave interferometer which combines the advantages of conventional Bragg- and Raman-type concepts. This feature leads to an interferometer with a high immunity to technical noise allowing us to devise a large-area Sagnac gyroscope yielding a phase shift of 6.5 rad due to the Earth's rotation. With this device we achieve a rotation rate precision of 120  nrad s(-1) Hz(-1/2) and determine the Earth's rotation rate with a relative uncertainty of 1.2%. PMID:25723216

  4. TRB3: a 264 channel high precision TDC platform and its applications

    NASA Astrophysics Data System (ADS)

    Neiser, A.; Adamczewski-Musch, J.; Hoek, M.; Koenig, W.; Korcyl, G.; Linev, S.; Maier, L.; Michel, J.; Palka, M.; Penschuck, M.; Traxler, M.; Uğur, C.; Zink, A.

    2013-12-01

    The TRB3 features four FPGA-based TDCs with < 20 ps RMS time precision between two channels and 256+4+4 channels in total. One central FPGA provides flexible trigger functionality and GbE connectivity including powerful slow control. We present recent users' applications of this platform following the COME&KISS principle: successful test beamtimes at CERN (CBM), in Jülich and Mainz with an FPGA-based discriminator board (PaDiWa), a charge-to-width FEE board with high dynamic range, read-out of the n-XYTER ASIC and software for data unpacking and TDC calibration in ROOT. We conclude with an outlook on future developments.

  5. 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.

  6. A cell for high-precision constant-current coulometry with external generation of titrant.

    PubMed

    Knoeck, J; Diehl, H

    1969-05-01

    A cell has been designed for the high-precision coulometric titration, with externally generated titrant, of materials which otherwise undergo undesirable reactions at the working electrodes. With this cell potassium dichromate has been titrated, via its hydrolysis reaction, with hydroxyl ion generated at the cathode, cathodic reduction of the chromium(VI) being circumvented. In this cell 99.9% of the titrant required is generated in one chamber and transferred to another for reaction; the titration is then completed with titrant generated at a second, drip-type electrode working at much lower current. By means of commercially available Leeds and Northrup coulometric titration electrical equipment, titration of NBS 136b Potassium Dichromate gave a purity of 99.976%, standard deviation 0.005%, and of NBS 84d Potassium Acid Phthalate (done as a check) 99.991%, standard deviation 0.005%, both values being in excellent agreement with other work.

  7. A Direct Comparison of Two High Precision Relative Gravity Meters at Optimal Performance

    NASA Astrophysics Data System (ADS)

    van Westrum, D.

    2015-12-01

    NGS has maintained and operated GWR Superconducting Gravimeter #024 since 1995. It has been widely considered one of the most quiet instruments from that era. It was recently upgraded with state of the art electronics and its operating parameters reoptimzied. A Micro-g LaCoste gPhoneX, installed on a high precision tilt table, was collocated with the SG at the Table Mountain Geophysical Observatory near Boulder, CO and the two instruments operated side by side for approximately two months. Results in both the frequency domain and selected time series from large seismic signals (e.g. earthquakes) will be presented, allowing for a direct comparison between the instruments in identical, ideal conditions.

  8. High Precision Measurement of the Proton Elastic Form Factor Ratio at Low Q2

    SciTech Connect

    Xiaohui Zhan

    2009-12-01

    A high precision measurement of the proton elastic form factor ratio µpGEp/GMp in the range Q2 = 0.3–0.7 GeV2/c2 was performed using recoil polarimetry in Jefferson Lab Hall A. In this low Q2 range, previous data from LEDEX [5] along with many fits and calculations [2, 3, 4] indicate substantial deviations of the ratio from unity. In this new measurement, with 80% polarized electron beam for 24 days, we are able to achieve <1% statistical uncertainty. Preliminary results are a few percent lower than expected from previous world data and fits, indicating a smaller GEp at this region. Beyond the intrinsic interest in nucleon structure, the improved form factor measurements also have implications for DVCS, determinations of the proton Zemach radius and strangeness form factors through parity violation experiments.

  9. Third-eye guided telemeter for high-precision positional measurement

    NASA Astrophysics Data System (ADS)

    Pettiti, Giuseppe; Cumani, Aldo; Grattoni, Paolo; Guiducci, Antonio; Pollastri, Fabrizio; Rebaglia, Bruno

    1994-02-01

    The telemeter is a high precision positional tracking device that works by triangulation over the angular measurements provided by two or more telegoniometers. Each of the latter is composed of a TV camera with a teleobjective, looking at the working space through a pair of orthogonal mirrors. A problem with this kind of structure is the automation of the initial pointing of the telegoniometers on the target. We propose to add a third camera with a wide- angle lens framing the whole workspace to provide the line of sight on which the target must lie. In this work we present this `three-eyes' structure and discuss its calibration, as well as the problems related to the strategy for scanning the line of sight and for detecting the tracking condition. Two possible applications to robot qualification and autonomous navigation also are presented.

  10. High-precision calculation of the strange nucleon electromagnetic form factors

    SciTech Connect

    Green, Jeremy; Meinel, Stefan; Engelhardt, Michael G.; Krieg, Stefan; Laeuchli, Jesse; Negele, John W.; Orginos, Kostas; Pochinsky, Andrew; Syritsyn, Sergey

    2015-08-26

    We report a direct lattice QCD calculation of the strange nucleon electromagnetic form factors GsE and GsM in the kinematic range 0 ≤ Q2 ≤ 1.2GeV2. For the first time, both GsE and GsM are shown to be nonzero with high significance. This work uses closer-to-physical lattice parameters than previous calculations, and achieves an unprecented statistical precision by implementing a recently proposed variance reduction technique called hierarchical probing. We perform model-independent fits of the form factor shapes using the z-expansion and determine the strange electric and magnetic radii and magnetic moment. As a result, we compare our results to parity-violating electron-proton scattering data and to other theoretical studies.

  11. High-precision follow-up observations of Near-Earth Objects

    NASA Astrophysics Data System (ADS)

    Ramanjooloo, Yudish; Tholen, David J.; Fohring, Dora; Hung, Denise

    2016-10-01

    We present the latest results of ongoing high-precision astrometric follow-up observations of Near-Earth Objects (NEOs) using the University of Hawaii 2.24 metre telescope (currently 7.5 arcmin FOV), the Canada-France-Hawaii Telescope (CFHT; 1 degree FOV) with MegaPrime, and the Subaru Hyper Suprime-Cam (1.5 degree FOV). The combination of excellent observing conditions at Maunakea, and the use of no filter to maximise our throughput efficiency, allows us to recover targets having V < 24, and sometimes V < 25 under ideal conditions. We frequently achieve astrometric accuracy limited by the reference catalog and plan to improve on this capability with the implementation of the GAIA catalog. This work is funded by NASA grant NXX13AI64G.

  12. High precision electric gate for time-of-flight ion mass spectrometers

    NASA Technical Reports Server (NTRS)

    Sittler, Edward C. (Inventor)

    2011-01-01

    A time-of-flight mass spectrometer having a chamber with electrodes to generate an electric field in the chamber and electric gating for allowing ions with a predetermined mass and velocity into the electric field. The design uses a row of very thin parallel aligned wires that are pulsed in sequence so the ion can pass through the gap of two parallel plates, which are biased to prevent passage of the ion. This design by itself can provide a high mass resolution capability and a very precise start pulse for an ion mass spectrometer. Furthermore, the ion will only pass through the chamber if it is within a wire diameter of the first wire when it is pulsed and has the right speed so it is near all other wires when they are pulsed.

  13. Non-contact high precision measurement of surface form tolerances and central thickness for optical elements

    NASA Astrophysics Data System (ADS)

    Lou, Ying

    2010-10-01

    The traditional contact measuring methods could not satisfy the current optical elements measuring requirements. Noncontact high precision measuring theory, principle and instrument of the surface form tolerances and central thickness for optical elements were studied in the paper. In comparison with other types of interferometers, such as Twyman-Green and Mach-Zehnder, a Fizeau interferometer has the advantages of having fewer optical components, greater accuracy, and is easier to use. Some relations among the 3/A(B/C), POWER/PV and N/ΔN were studied. The PV with POWER removed can be the reference number of ΔN. The chromatic longitudinal aberration of a special optical probe can be used for non-contanct central thickness measurement.

  14. High-precision locations of the microseismicity preceding the 2002-2003 Mt. Etna eruption

    NASA Astrophysics Data System (ADS)

    Gambino, S.; Mostaccio, A.; Patanè, D.; Scarfì, L.; Ursino, A.

    2004-09-01

    To recognize possible signals of intrusive processes leading to the last 2002-2003 flank eruption at Mt. Etna, we analyzed the spatial pattern of microseismicity between August 2001 and October 2002 and calculated 23 fault plane solutions (FPSs) for shocks with magnitude greater than 2.5. By applying the double-difference approach of Waldhauser and Ellsworth [2000] on 3D locations, we found that most of the scattered epicentral locations further collapse in roughly linear features. High-precision locations evidenced a distribution of earthquakes along two main alignments, oriented NE-SW to ENE-WSW and NW-SE, matching well both with the known tectonic and volcanic lineaments of Etna and FPSs results. Moreover, microseismicity and swarms located along the NNW-SSE volcano-genetic trend suggest, together with geodetic data and volcanological evidence that progressive magma refilling has occurred since February 2002.

  15. Influence of sulfur-bearing polyatomic species on high precision measurements of Cu isotopic composition

    USGS Publications Warehouse

    Pribil, M.J.; Wanty, R.B.; Ridley, W.I.; Borrok, D.M.

    2010-01-01

    An increased interest in high precision Cu isotope ratio measurements using multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) has developed recently for various natural geologic systems and environmental applications, these typically contain high concentrations of sulfur, particularly in the form of sulfate (SO42-) and sulfide (S). For example, Cu, Fe, and Zn concentrations in acid mine drainage (AMD) can range from 100??g/L to greater than 50mg/L with sulfur species concentrations reaching greater than 1000mg/L. Routine separation of Cu, Fe and Zn from AMD, Cu-sulfide minerals and other geological matrices usually incorporates single anion exchange resin column chromatography for metal separation. During chromatographic separation, variable breakthrough of SO42- during anion exchange resin column chromatography into the Cu fractions was observed as a function of the initial sulfur to Cu ratio, column properties, and the sample matrix. SO42- present in the Cu fraction can form a polyatomic 32S-14N-16O-1H species causing a direct mass interference with 63Cu and producing artificially light ??65Cu values. Here we report the extent of the mass interference caused by SO42- breakthrough when measuring ??65Cu on natural samples and NIST SRM 976 Cu isotope spiked with SO42- after both single anion column chromatography and double anion column chromatography. A set of five 100??g/L Cu SRM 976 samples spiked with 500mg/L SO42- resulted in an average ??65Cu of -3.50?????5.42??? following single anion column separation with variable SO42- breakthrough but an average concentration of 770??g/L. Following double anion column separation, the average SO42-concentration of 13??g/L resulted in better precision and accuracy for the measured ??65Cu value of 0.01?????0.02??? relative to the expected 0??? for SRM 976. We conclude that attention to SO42- breakthrough on sulfur-rich samples is necessary for accurate and precise measurements of ??65Cu and may require

  16. High-Precision Stable Isotope Analyses with the NanoSIMS 50L (Invited)

    NASA Astrophysics Data System (ADS)

    Hauri, E. H.; Wang, J.; Papineau, D.; Hillion, F.

    2009-12-01

    The in situ measurement of isotope ratios at high precision has always been a goal of secondary ion mass spectrometery (SIMS). The NanoSIMS 50L is a third-generation ion microprobe developed by Cameca and modified in collaboration with the Carnegie Institution of Washington. This instrument encorporates a number of design and functional improvements over the stock NS50, including precise stepper motor control over all slits, apertures and stage movements, a larger magnet, and a modified multicollector (6 moveable and 1 fixed) capable of holding both Faraday cups and miniature multi-dynode electron multipliers. The instrument is capable of attaining a minimum beam diameter of <50 nanometers with Cs and <200 nanometers with oxygen, a factor of 5-10 improvement over the IMS6F/7F/1280 generation of instruments. The CIW instrument is also the first NanoSIMS to be fitted with multiple Faradays and associated high-precision electrometers. Most tests to date have been performed on conductive Fe-bearing sulfides mouted in indium and polished with near-zero relief. With Cs, a routine primary beam diameter of 100 nm is obtained with 1-2pA of current, sufficient to yield 1MHz of 32S from pyrite at >6000 MRP. A 2.5 nA Cs beam with a diameter of 700 nm yields 90 pA of 32S from pyrite at >6000 MRP, sufficient to analyze 32S-33S-34S on Faraday cups and 36S in EM @ >10,000 cps. Specification tests immediately after installation in 2005 demonstrated a reproducibility of <0.3‰ (1σ) in 10 analyses within a single sputter crater on Balmat pyrite, and this was subsequently improved to 0.15‰ (1σ) in 2006. Further tests showed that reproducibility on separate craters of a single grain, and separate craters in separate Balmat pyrite grains located in different holes of the sample holder, were improved to better than 0.2‰ (1σ) through careful attention to reproducibility of sample height (Z-axis control) and centering of the secondary ion beam in the entrance slit of the mass

  17. Redefining ALL classification: toward detecting high-risk ALL and implementing precision medicine

    PubMed Central

    Hunger, Stephen P.

    2015-01-01

    Acute lymphoblastic leukemia (ALL) is the commonest childhood tumor and remains a leading cause of cancer death in the young. In the last decade, microarray and sequencing analysis of large ALL cohorts has revolutionized our understanding of the genetic basis of this disease. These studies have identified new ALL subtypes, each characterized by constellations of structural and sequence alterations that perturb key cellular pathways, including lymphoid development, cell-cycle regulation, and tumor suppression; cytokine receptor, kinase, and Ras signaling; and chromatin modifications. Several of these pathways, particularly kinase-activating lesions and epigenetic alterations, are logical targets for new precision medicine therapies. Genomic profiling has also identified important interactions between inherited genetic variants that influence the risk of leukemia development and the somatic genetic alterations that are required to establish the leukemic clone. Moreover, sequential sequencing studies at diagnosis, remission, and relapse have provided important insights into the relationship among genetic variants, clonal heterogeneity, and the risk of relapse. Ongoing studies are extending our understanding of coding and noncoding genetic alterations in B-progenitor and T-lineage ALL and using these insights to inform the development of faithful experimental models to test the efficacy of new treatment approaches. PMID:25999453

  18. Multi-Repeated Projection Lithography for High-Precision Linear Scale Based on Average Homogenization Effect.

    PubMed

    Ren, Dongxu; Zhao, Huiying; Zhang, Chupeng; Yuan, Daocheng; Xi, Jianpu; Zhu, Xueliang; Ban, Xinxing; Dong, Longchao; Gu, Yawen; Jiang, Chunye

    2016-04-14

    A multi-repeated photolithography method for manufacturing an incremental linear scale using projection lithography is presented. The method is based on the average homogenization effect that periodically superposes the light intensity of different locations of pitches in the mask to make a consistent energy distribution at a specific wavelength, from which the accuracy of a linear scale can be improved precisely using the average pitch with different step distances. The method's theoretical error is within 0.01 µm for a periodic mask with a 2-µm sine-wave error. The intensity error models in the focal plane include the rectangular grating error on the mask, static positioning error, and lithography lens focal plane alignment error, which affect pitch uniformity less than in the common linear scale projection lithography splicing process. It was analyzed and confirmed that increasing the repeat exposure number of a single stripe could improve accuracy, as could adjusting the exposure spacing to achieve a set proportion of black and white stripes. According to the experimental results, the effectiveness of the multi-repeated photolithography method is confirmed to easily realize a pitch accuracy of 43 nm in any 10 locations of 1 m, and the whole length accuracy of the linear scale is less than 1 µm/m.

  19. Multi-Repeated Projection Lithography for High-Precision Linear Scale Based on Average Homogenization Effect

    PubMed Central

    Ren, Dongxu; Zhao, Huiying; Zhang, Chupeng; Yuan, Daocheng; Xi, Jianpu; Zhu, Xueliang; Ban, Xinxing; Dong, Longchao; Gu, Yawen; Jiang, Chunye

    2016-01-01

    A multi-repeated photolithography method for manufacturing an incremental linear scale using projection lithography is presented. The method is based on the average homogenization effect that periodically superposes the light intensity of different locations of pitches in the mask to make a consistent energy distribution at a specific wavelength, from which the accuracy of a linear scale can be improved precisely using the average pitch with different step distances. The method’s theoretical error is within 0.01 µm for a periodic mask with a 2-µm sine-wave error. The intensity error models in the focal plane include the rectangular grating error on the mask, static positioning error, and lithography lens focal plane alignment error, which affect pitch uniformity less than in the common linear scale projection lithography splicing process. It was analyzed and confirmed that increasing the repeat exposure number of a single stripe could improve accuracy, as could adjusting the exposure spacing to achieve a set proportion of black and white stripes. According to the experimental results, the effectiveness of the multi-repeated photolithography method is confirmed to easily realize a pitch accuracy of 43 nm in any 10 locations of 1 m, and the whole length accuracy of the linear scale is less than 1 µm/m. PMID:27089348

  20. [High Precision Identification of Igneous Rock Lithology by Laser Induced Breakdown Spectroscopy].

    PubMed

    Wang, Chao; Zhang, Wei-gang; Yan, Zhi-quan

    2015-09-01

    In the field of petroleum exploration, lithology identification of finely cuttings sample, especially high precision identification of igneous rock with similar property, has become one of the geological problems. In order to solve this problem, a new method is proposed based on element analysis of Laser-Induced Breakdown Spectroscopy (LIBS) and Total Alkali versus Silica (TAS) diagram. Using independent LIBS system, factors influencing spectral signal, such as pulse energy, acquisition time delay, spectrum acquisition method and pre-ablation are researched through contrast experiments systematically. The best analysis conditions of igneous rock are determined: pulse energy is 50 mJ, acquisition time delay is 2 μs, the analysis result is integral average of 20 different points of sample's surface, and pre-ablation has been proved not suitable for igneous rock sample by experiment. The repeatability of spectral data is improved effectively. Characteristic lines of 7 elements (Na, Mg, Al, Si, K, Ca, Fe) commonly used for lithology identification of igneous rock are determined, and igneous rock samples of different lithology are analyzed and compared. Calibration curves of Na, K, Si are generated by using national standard series of rock samples, and all the linearly dependent coefficients are greater than 0.9. The accuracy of quantitative analysis is investigated by national standard samples. Element content of igneous rock is analyzed quantitatively by calibration curve, and its lithology is identified accurately by the method of TAS diagram, whose accuracy rate is 90.7%. The study indicates that LIBS can effectively achieve the high precision identification of the lithology of igneous rock.

  1. A high precision dual feedback discrete control system designed for satellite trajectory simulator

    NASA Astrophysics Data System (ADS)

    Liu, Ximin; Liu, Liren; Sun, Jianfeng; Xu, Nan

    2005-08-01

    Cooperating with the free-space laser communication terminals, the satellite trajectory simulator is used to test the acquisition, pointing, tracking and communicating performances of the terminals. So the satellite trajectory simulator plays an important role in terminal ground test and verification. Using the double-prism, Sun etc in our group designed a satellite trajectory simulator. In this paper, a high precision dual feedback discrete control system designed for the simulator is given and a digital fabrication of the simulator is made correspondingly. In the dual feedback discrete control system, Proportional- Integral controller is used in velocity feedback loop and Proportional- Integral- Derivative controller is used in position feedback loop. In the controller design, simplex method is introduced and an improvement to the method is made. According to the transfer function of the control system in Z domain, the digital fabrication of the simulator is given when it is exposed to mechanism error and moment disturbance. Typically, when the mechanism error is 100urad, the residual standard error of pitching angle, azimuth angle, x-coordinate position and y-coordinate position are 0.49urad, 6.12urad, 4.56urad, 4.09urad respectively. When the moment disturbance is 0.1rad, the residual standard error of pitching angle, azimuth angle, x-coordinate position and y-coordinate position are 0.26urad, 0.22urad, 0.16urad, 0.15urad respectively. The digital fabrication results demonstrate that the dual feedback discrete control system designed for the simulator can achieve the anticipated high precision performance.

  2. [High Precision Identification of Igneous Rock Lithology by Laser Induced Breakdown Spectroscopy].

    PubMed

    Wang, Chao; Zhang, Wei-gang; Yan, Zhi-quan

    2015-09-01

    In the field of petroleum exploration, lithology identification of finely cuttings sample, especially high precision identification of igneous rock with similar property, has become one of the geological problems. In order to solve this problem, a new method is proposed based on element analysis of Laser-Induced Breakdown Spectroscopy (LIBS) and Total Alkali versus Silica (TAS) diagram. Using independent LIBS system, factors influencing spectral signal, such as pulse energy, acquisition time delay, spectrum acquisition method and pre-ablation are researched through contrast experiments systematically. The best analysis conditions of igneous rock are determined: pulse energy is 50 mJ, acquisition time delay is 2 μs, the analysis result is integral average of 20 different points of sample's surface, and pre-ablation has been proved not suitable for igneous rock sample by experiment. The repeatability of spectral data is improved effectively. Characteristic lines of 7 elements (Na, Mg, Al, Si, K, Ca, Fe) commonly used for lithology identification of igneous rock are determined, and igneous rock samples of different lithology are analyzed and compared. Calibration curves of Na, K, Si are generated by using national standard series of rock samples, and all the linearly dependent coefficients are greater than 0.9. The accuracy of quantitative analysis is investigated by national standard samples. Element content of igneous rock is analyzed quantitatively by calibration curve, and its lithology is identified accurately by the method of TAS diagram, whose accuracy rate is 90.7%. The study indicates that LIBS can effectively achieve the high precision identification of the lithology of igneous rock. PMID:26669148

  3. A fast high-precision six-degree-of-freedom relative position sensor

    NASA Astrophysics Data System (ADS)

    Hughes, Gary B.; Macasaet, Van P.; Griswold, Janelle; Sison, Claudia A.; Lubin, Philip; Meinhold, Peter; Suen, Jonathan; Brashears, Travis; Zhang, Qicheng; Madajian, Jonathan

    2016-03-01

    Lasers are commonly used in high-precision measurement and profiling systems. Some laser measurement systems are based on interferometry principles, and others are based on active triangulation, depending on requirements of the application. This paper describes an active triangulation laser measurement system for a specific application wherein the relative position of two fixed, rigid mechanical components is to be measured dynamically with high precision in six degrees of freedom (DOF). Potential applications include optical systems with feedback to control for mechanical vibration, such as target acquisition devices with multiple focal planes. The method uses an array of several laser emitters mounted on one component. The lasers are directed at a reflective surface on the second component. The reflective surface consists of a piecewise-planar pattern such as a pyramid, or more generally a curved reflective surface such as a hyperbolic paraboloid. The reflected spots are sensed at 2-dimensional photodiode arrays on the emitter component. Changes in the relative position of the emitter component and reflective surface will shift the location of the reflected spots within photodiode arrays. Relative motion in any degree of freedom produces independent shifts in the reflected spot locations, allowing full six-DOF relative position determination between the two component positions. Response time of the sensor is limited by the read-out rate of the photodiode arrays. Algorithms are given for position determination with limits on uncertainty and sensitivity, based on laser and spot-sensor characteristics, and assuming regular surfaces. Additional uncertainty analysis is achievable for surface irregularities based on calibration data.

  4. CORRECTING FOR INTERSTELLAR SCATTERING DELAY IN HIGH-PRECISION PULSAR TIMING: SIMULATION RESULTS

    SciTech Connect

    Palliyaguru, Nipuni; McLaughlin, Maura; Stinebring, Daniel; Demorest, Paul; Jones, Glenn E-mail: maura.mclaughlin@mail.wvu.edu E-mail: pdemores@nrao.edu

    2015-12-20

    Light travel time changes due to gravitational waves (GWs) may be detected within the next decade through precision timing of millisecond pulsars. Removal of frequency-dependent interstellar medium (ISM) delays due to dispersion and scattering is a key issue in the detection process. Current timing algorithms routinely correct pulse times of arrival (TOAs) for time-variable delays due to cold plasma dispersion. However, none of the major pulsar timing groups correct for delays due to scattering from multi-path propagation in the ISM. Scattering introduces a frequency-dependent phase change in the signal that results in pulse broadening and arrival time delays. Any method to correct the TOA for interstellar propagation effects must be based on multi-frequency measurements that can effectively separate dispersion and scattering delay terms from frequency-independent perturbations such as those due to a GW. Cyclic spectroscopy, first described in an astronomical context by Demorest (2011), is a potentially powerful tool to assist in this multi-frequency decomposition. As a step toward a more comprehensive ISM propagation delay correction, we demonstrate through a simulation that we can accurately recover impulse response functions (IRFs), such as those that would be introduced by multi-path scattering, with a realistic signal-to-noise ratio (S/N). We demonstrate that timing precision is improved when scatter-corrected TOAs are used, under the assumptions of a high S/N and highly scattered signal. We also show that the effect of pulse-to-pulse “jitter” is not a serious problem for IRF reconstruction, at least for jitter levels comparable to those observed in several bright pulsars.

  5. Correcting for Interstellar Scattering Delay in High-precision Pulsar Timing: Simulation Results

    NASA Astrophysics Data System (ADS)

    Palliyaguru, Nipuni; Stinebring, Daniel; McLaughlin, Maura; Demorest, Paul; Jones, Glenn

    2015-12-01

    Light travel time changes due to gravitational waves (GWs) may be detected within the next decade through precision timing of millisecond pulsars. Removal of frequency-dependent interstellar medium (ISM) delays due to dispersion and scattering is a key issue in the detection process. Current timing algorithms routinely correct pulse times of arrival (TOAs) for time-variable delays due to cold plasma dispersion. However, none of the major pulsar timing groups correct for delays due to scattering from multi-path propagation in the ISM. Scattering introduces a frequency-dependent phase change in the signal that results in pulse broadening and arrival time delays. Any method to correct the TOA for interstellar propagation effects must be based on multi-frequency measurements that can effectively separate dispersion and scattering delay terms from frequency-independent perturbations such as those due to a GW. Cyclic spectroscopy, first described in an astronomical context by Demorest (2011), is a potentially powerful tool to assist in this multi-frequency decomposition. As a step toward a more comprehensive ISM propagation delay correction, we demonstrate through a simulation that we can accurately recover impulse response functions (IRFs), such as those that would be introduced by multi-path scattering, with a realistic signal-to-noise ratio (S/N). We demonstrate that timing precision is improved when scatter-corrected TOAs are used, under the assumptions of a high S/N and highly scattered signal. We also show that the effect of pulse-to-pulse “jitter” is not a serious problem for IRF reconstruction, at least for jitter levels comparable to those observed in several bright pulsars.

  6. Capability for ozone high-precision retrieval on JEM/SMILES observation

    NASA Astrophysics Data System (ADS)

    Takahashi, Chikako; Suzuki, Makoto; Mitsuda, Chihiro; Ochiai, Satoshi; Manago, Naohiro; Hayashi, Hiroo; Iwata, Yoshitaka; Imai, Koji; Sano, Takuki; Takayanagi, Masahiro; Shiotani, Masato

    2011-09-01

    We estimate the capability of ozone (O 3) retrieval with the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) instrument attached to the Exposed Facility of the Japanese Experiment Module (JEM) on the International Space Station (ISS). SMILES carries a 4-K mechanical refrigerator to cool superconducting devices in space. Since SMILES has high sensitivity thanks to the superconducting receiver, it is expected that SMILES has ability to retrieve O 3 profiles more precisely than the previous millimeter-submillimeter limb measurements from satellites. We examine the random error and the systematic error of O 3 vertical profiles based on the launch-ready retrieval algorithm developed for SMILES. The best random error with single-scan spectra is 0.4% at an altitude of 30 km with 3 km vertical resolution in the mid-latitudes. The random error is better than 5% in the altitude region from 15 to 70 km in the nighttime and from 15 to 55 km in the daytime with 3 km vertical resolution in the mid-latitudes. By averaging ten profiles, the random error is improved to 1% at 70 km altitude in the nighttime and to 5% in the daytime. Using SMILES, we expect to determine the diurnal variation of O 3 vertical profiles with high precision in the upper stratosphere. Finally, the retrieval capability of O 3 in the lower stratosphere is estimated. When retrieving spectral data using two receiver bands (624.32-626.32 GHz and 649.12-650.32 GHz) the random error above 13 km in the mid-latitudes and above 15 km in the tropics is expected to be better than 5% under clear sky conditions.

  7. Frontiers of QC Laser spectroscopy for high precision isotope ratio analysis of greenhouse gases

    NASA Astrophysics Data System (ADS)

    Emmenegger, Lukas; Mohn, Joachim; Harris, Eliza; Eyer, Simon; Ibraim, Erkan; Tuzson, Béla

    2016-04-01

    An important milestone for laser spectroscopy was achieved when isotope ratios of greenhouse gases were reported at precision levels that allow addressing research questions in environmental sciences. Real-time data with high temporal resolution at moderate cost and instrument size make the optical approach highly attractive, complementary to the well-established isotope-ratio mass-spectrometry (IRMS) method. Especially appealing, in comparison to IRMS, is the inherent specificity to structural isomers having the same molecular mass. Direct absorption in the MIR in single or dual QCL configuration has proven highly reliable for the sta-ble isotopes of CO2, N2O and CH4. The longest time series of real-time measurements is currently available for δ13C and δ18O in CO2 at the high-alpine station Jung-fraujoch. At this well-equipped site, QCL based direct absorption spectroscopy (QCLAS) measurements are ongoing since 2008 1,2. Applications of QCLAS for N2O and CH4 stable isotopes are considerably more challenging because of the lower atmospheric mixing ratios, especially for the less abundant species, such as N218O and CH3D. For high precision (< 0.1 ‰) measurements in ambient air, QCLAS may be combined with a fully automated preconcentration unit yielding an up to 500 times concentration increase and the capability to separate the target gas from spectral interferants by se-quential desorption 3. Here, we review our recent developments on high precision isotope ratio analysis of greenhouse gases, with special focus on the isotopic species of N2O and CH4. Furthermore, we show environ-mental applications illustrating the highly valuable information that isotope ratios of atmospheric trace gases can carry. For example, the intramolecular distribution of 15N in N2O gives important information on the geochemical cycle of N2O4-6, while the analysis of δ13C and δ D in CH4 may be applied to disentangle microbial, fossil and landfill sources 7. 1 Sturm, P., Tuzson, B

  8. Learning to combine high variability with high precision: lack of transfer to a different task.

    PubMed

    Wu, Yen-Hsun; Truglio, Thomas S; Zatsiorsky, Vladimir M; Latash, Mark L

    2015-01-01

    The authors studied effects of practicing a 4-finger accurate force production task on multifinger coordination quantified within the uncontrolled manifold hypothesis. During practice, task instability was modified by changing visual feedback gain based on accuracy of performance. The authors also explored the retention of these effects, and their transfer to a prehensile task. Subjects practiced the force production task for 2 days. After the practice, total force variability decreased and performance became more accurate. In contrast, variance of finger forces showed a tendency to increase during the first practice session while in the space of finger modes (hypothetical commands to fingers) the increase was under the significance level. These effects were retained for 2 weeks. No transfer of these effects to the prehensile task was seen, suggesting high specificity of coordination changes. The retention of practice effects without transfer to a different task suggests that further studies on a more practical method of improving coordination are needed. PMID:25365477

  9. Learning to combine high variability with high precision: lack of transfer to a different task.

    PubMed

    Wu, Yen-Hsun; Truglio, Thomas S; Zatsiorsky, Vladimir M; Latash, Mark L

    2015-01-01

    The authors studied effects of practicing a 4-finger accurate force production task on multifinger coordination quantified within the uncontrolled manifold hypothesis. During practice, task instability was modified by changing visual feedback gain based on accuracy of performance. The authors also explored the retention of these effects, and their transfer to a prehensile task. Subjects practiced the force production task for 2 days. After the practice, total force variability decreased and performance became more accurate. In contrast, variance of finger forces showed a tendency to increase during the first practice session while in the space of finger modes (hypothetical commands to fingers) the increase was under the significance level. These effects were retained for 2 weeks. No transfer of these effects to the prehensile task was seen, suggesting high specificity of coordination changes. The retention of practice effects without transfer to a different task suggests that further studies on a more practical method of improving coordination are needed.

  10. Correlated cryo-fluorescence and cryo-electron microscopy with high spatial precision and improved sensitivity.

    PubMed

    Schorb, Martin; Briggs, John A G

    2014-08-01

    Performing fluorescence microscopy and electron microscopy on the same sample allows fluorescent signals to be used to identify and locate features of interest for subsequent imaging by electron microscopy. To carry out such correlative microscopy on vitrified samples appropriate for structural cryo-electron microscopy it is necessary to perform fluorescence microscopy at liquid-nitrogen temperatures. Here we describe an adaptation of a cryo-light microscopy stage to permit use of high-numerical aperture objectives. This allows high-sensitivity and high-resolution fluorescence microscopy of vitrified samples. We describe and apply a correlative cryo-fluorescence and cryo-electron microscopy workflow together with a fiducial bead-based image correlation procedure. This procedure allows us to locate fluorescent bacteriophages in cryo-electron microscopy images with an accuracy on the order of 50 nm, based on their fluorescent signal. It will allow the user to precisely and unambiguously identify and locate objects and events for subsequent high-resolution structural study, based on fluorescent signals.

  11. Investigation of detachment and transport processes of sediment using different sand mixtures in high precision rainfall simulations

    NASA Astrophysics Data System (ADS)

    Fister, Wolfgang; Mayer, Marius; Reichle, Elisabeth; Kinnell, Peter I. A.; Kuhn, Nikolaus J.

    2016-04-01

    Detachment and transport of sediment in the landscape are controlled by many different factors. Beside environmental factors such as soil surface properties, land management and vegetation cover, the dominant ones are rainfall and surface flow characteristics. In order to be able to investigate the change of sediment properties over transport distance and time, it is, therefore, necessary to understand the basic interactions between rainfall kinetic energy and amount, particle size and density as well as flow depth and velocity. So far, the mechanistic understanding of these principal physical interactions is mostly of empirical nature, obtained either under natural, highly complex and uncontrollable conditions, or with rainfall experiments that weren't able to control the conditions with high enough precision. The aim of this study was, therefore, to fill this gap of knowledge in our mechanical process understanding by conducting rainfall experiments on different sand mixtures. In this bottom-up approach, the highly controlled experimental conditions and the use of stable sand ensured that the number of variable factors was kept to a minimum. Thus, specific relations between sand-sizes, drop kinetic energy, force of flow, and resulting erosion rates could be obtained. Although the results are very promising and could lead to a better understanding of the erosion processes in the future, they clearly show that already straightforward sand mixtures behave in a very complex way. Further experiments with simple grain mixtures are, therefore, needed before experiments on more complex, instable sediments can or should be investigated.

  12. HPMSS(High Precision Magnetic Survey System) and InterRidge

    NASA Astrophysics Data System (ADS)

    Isezaki, N.; Sayanagi, K.

    2012-12-01

    From the beginning of 1990s to the beginning of 2000s, the Japanese group of IntreRidge conducted many cruises for three component magnetic survey using Shipboard Three Component Magnetometer (STCM) and Deep Towed Three Component Magnetometer (DTCM) in the world wide oceans. We have been developing HPMSS during this time with support of Dr.Tamaki(the late representative of InterRidge Japan) who understood the advantages of three component geomagnetic anomalies (TCGA). TCGA measured by STCM determines the direction of geomagnetic anomaly lineations precisely at every point where TCGA were observed, which playes the important role in magnetic anomaly lineation analysis. Even in the beginning of 2000s, almost all marine magnetic scientists believed that the total intensity anomly (TIA) is the better data than TCGA for analysis because the scalar magnetometers (e.g. proton precession magnetometer) have the better accuracy than any other magnetometers (e.g.flux gate magnetometer (FGM)). We employed the high accrate gyroscope (e.g.ring lase gyroscope (RLG)/optical fiber gyroscope (OFG)) to improve the accuracy of STCM/DTCM equipped with FGM. Moreover we employed accurate and precise FGM which was selected among the market. Finally we developed the new magnetic survey system with high precision usable as airborn, shipboard and dee-ptowed magnetometers which we call HPMSS(High Precision Magnetic Survey System). As an optional equipment, we use LAN to communicate between a data aquisiitin part and a data logging part, and GPS for a position fix. For the deep-towed survey, we use the acoustic position fix (super short base line method) and the acoustic communication to monitor the DTCM status. First we used HPMSS to obtain the magnetization structure of the volcanic island, Aogashima located 300km south of Tokyo using a hellcopter in 2006 and 2009. Next we used HPMSS installed in DTCM in 2010,2011 and 2012 using R/V Bosei-maru belonging to Tokai University. Also we used

  13. High precision and high aspect ratio laser drilling: challenges and solutions

    NASA Astrophysics Data System (ADS)

    Uchtmann, Hermann; He, Chao; Gillner, Arnold

    2016-03-01

    Laser drilling is a very versatile tool to produce high accuracy bores in small and large geometries using different technologies. In large and deep hole drilling laser drilling can be found in drilling cooling holes into turbomachinery components such as turbine blades. In micro drilling, the technology is used for the generation of nozzles and filters. However, especially in macro drilling, the process often causes microstructure changes and induces defects such as recast layers and cracks. The defects are caused by the melt dominated drilling process by using pulse durations in the range of some 100 μm up to a few ms. A solution of this problem is the use of ultrashort pulsed laser radiation with pulse durations in the range of some 100 fs up to a few ps, however with the disadvantage of long drilling times. Thus, the aim of this work is to combine the productive process by using ms pulsed fiber laser radiation with subsequent ablation of existing recast layers at the hole wall by using ultrashort pulsed laser radiation. By using fast scanning techniques the recast layer can be avoided almost completely. With a similar technology also very small hole can be produced. Using a rotating dove prism a circular oscillation of the laser spots is performed and holes are drilled at intervals in 1 mm thick stainless steel (1.4301) by ultra-short laser pulses of 7 ps at 515 nm. The formation of hole and the behavior of energy deposition differ from other drilling strategies due to the helical revolution. The temporal evolution of the hole shape is analyzed by means of SEM techniques from which three drilling phases can be distinguished.

  14. QCD Precision Measurements and Structure Function Extraction at a High Statistics, High Energy Neutrino Scattering Experiment: NuSOnG

    SciTech Connect

    Adams, T.; Batra, P.; Bugel, Leonard G.; Camilleri, Leslie Loris; Conrad, Janet Marie; de Gouvea, A.; Fisher, Peter H.; Formaggio, Joseph Angelo; Jenkins, J.; Karagiorgi, Georgia S.; Kobilarcik, T.R.; /Fermilab /Texas U.

    2009-06-01

    We extend the physics case for a new high-energy, ultra-high statistics neutrino scattering experiment, NuSOnG (Neutrino Scattering On Glass) to address a variety of issues including precision QCD measurements, extraction of structure functions, and the derived Parton Distribution Functions (PDFs). This experiment uses a Tevatron-based neutrino beam to obtain a sample of Deep Inelastic Scattering (DIS) events which is over two orders of magnitude larger than past samples. We outline an innovative method for fitting the structure functions using a parameterized energy shift which yields reduced systematic uncertainties. High statistics measurements, in combination with improved systematics, will enable NuSOnG to perform discerning tests of fundamental Standard Model parameters as we search for deviations which may hint of 'Beyond the Standard Model' physics.

  15. QCD Precision Measurements and Structure Function Extraction at a High Statistics, High Energy Neutrino Scattering Experiment:. NuSOnG

    NASA Astrophysics Data System (ADS)

    Adams, T.; Batra, P.; Bugel, L.; Camilleri, L.; Conrad, J. M.; de Gouvêa, A.; Fisher, P. H.; Formaggio, J. A.; Jenkins, J.; Karagiorgi, G.; Kobilarcik, T. R.; Kopp, S.; Kyle, G.; Loinaz, W. A.; Mason, D. A.; Milner, R.; Moore, R.; Morfín, J. G.; Nakamura, M.; Naples, D.; Nienaber, P.; Olness, F. I.; Owens, J. F.; Pate, S. F.; Pronin, A.; Seligman, W. G.; Shaevitz, M. H.; Schellman, H.; Schienbein, I.; Syphers, M. J.; Tait, T. M. P.; Takeuchi, T.; Tan, C. Y.; van de Water, R. G.; Yamamoto, R. K.; Yu, J. Y.

    We extend the physics case for a new high-energy, ultra-high statistics neutrino scattering experiment, NuSOnG (Neutrino Scattering On Glass) to address a variety of issues including precision QCD measurements, extraction of structure functions, and the derived Parton Distribution Functions (PDF's). This experiment uses a Tevatron-based neutrino beam to obtain a sample of Deep Inelastic Scattering (DIS) events which is over two orders of magnitude larger than past samples. We outline an innovative method for fitting the structure functions using a parametrized energy shift which yields reduced systematic uncertainties. High statistics measurements, in combination with improved systematics, will enable NuSOnG to perform discerning tests of fundamental Standard Model parameters as we search for deviations which may hint of "Beyond the Standard Model" physics.

  16. Globular Cluster Streams as Galactic High-Precision Scales—the Poster Child Palomar 5

    NASA Astrophysics Data System (ADS)

    Küpper, Andreas H. W.; Balbinot, Eduardo; Bonaca, Ana; Johnston, Kathryn V.; Hogg, David W.; Kroupa, Pavel; Santiago, Basilio X.

    2015-04-01

    Using the example of the tidal stream of the Milky Way globular cluster Palomar 5 (Pal 5), we demonstrate how observational data on tidal streams can be efficiently reduced in dimensionality and modeled in a Bayesian framework. Our approach combines detection of stream overdensities by a Difference-of-Gaussians process with fast streakline models of globular cluster streams and a continuous likelihood function built from these models. Inference is performed with Markov chain Monte Carlo. By generating ≈ {{10}7} model streams, we show that the unique geometry of the Pal 5 debris yields powerful constraints on the solar position and motion, the Milky Way and Pal 5 itself. All 10 model parameters were allowed to vary over large ranges without additional prior information. Using only readily available SDSS data and a few radial velocities from the literature, we find that the distance of the Sun from the Galactic Center is 8.30 ± 0.25 kpc, and the transverse velocity is 253 ± 16 km s-1. Both estimates are in excellent agreement with independent measurements of these two quantities. Assuming a standard disk and bulge model, we determine the Galactic mass within Pal 5's apogalactic radius of 19 kpc to be (2.1+/- 0.4)× {{10}11} {{M}⊙ }. Moreover, we find the potential of the dark halo with a flattening of {{q}z}=0.95-0.12+0.16 to be essentially spherical—at least within the radial range that is effectively probed by Pal 5. We also determine Pal 5's mass, distance, and proper motion independently from other methods, which enables us to perform vital cross-checks. Our inferred heliocentric distance of Pal 5 is 23.6-0.7+0.8 kpc, in perfect agreement with, and more precise than, estimates from isochrone fitting of deep Hubble Space Telescope (HST) imaging data. We conclude that finding and modeling more globular cluster streams is an efficient way to map out the structure of our Galaxy to high precision. With more observational data and by using additional prior

  17. Highly Precise and Developmentally Programmed Genome Assembly in Paramecium Requires Ligase IV–Dependent End Joining

    PubMed Central

    Marmignon, Antoine; Ku, Michael; Silve, Aude; Meyer, Eric; Forney, James D.; Malinsky, Sophie; Bétermier, Mireille

    2011-01-01

    During the sexual cycle of the ciliate Paramecium, assembly of the somatic genome includes the precise excision of tens of thousands of short, non-coding germline sequences (Internal Eliminated Sequences or IESs), each one flanked by two TA dinucleotides. It has been reported previously that these genome rearrangements are initiated by the introduction of developmentally programmed DNA double-strand breaks (DSBs), which depend on the domesticated transposase PiggyMac. These DSBs all exhibit a characteristic geometry, with 4-base 5′ overhangs centered on the conserved TA, and may readily align and undergo ligation with minimal processing. However, the molecular steps and actors involved in the final and precise assembly of somatic genes have remained unknown. We demonstrate here that Ligase IV and Xrcc4p, core components of the non-homologous end-joining pathway (NHEJ), are required both for the repair of IES excision sites and for the circularization of excised IESs. The transcription of LIG4 and XRCC4 is induced early during the sexual cycle and a Lig4p-GFP fusion protein accumulates in the developing somatic nucleus by the time IES excision takes place. RNAi–mediated silencing of either gene results in the persistence of free broken DNA ends, apparently protected against extensive resection. At the nucleotide level, controlled removal of the 5′-terminal nucleotide occurs normally in LIG4-silenced cells, while nucleotide addition to the 3′ ends of the breaks is blocked, together with the final joining step, indicative of a coupling between NHEJ polymerase and ligase activities. Taken together, our data indicate that IES excision is a “cut-and-close” mechanism, which involves the introduction of initiating double-strand cleavages at both ends of each IES, followed by DSB repair via highly precise end joining. This work broadens our current view on how the cellular NHEJ pathway has cooperated with domesticated transposases for the emergence of new

  18. Time-optimized laser micro machining by using a new high dynamic and high precision galvo scanner

    NASA Astrophysics Data System (ADS)

    Jaeggi, Beat; Neuenschwander, Beat; Zimmermann, Markus; Zecherle, Markus; Boeckler, Ernst W.

    2016-03-01

    High accuracy, quality and throughput are key factors in laser micro machining. To obtain these goals the ablation process, the machining strategy and the scanning device have to be optimized. The precision is influenced by the accuracy of the galvo scanner and can further be enhanced by synchronizing the movement of the mirrors with the laser pulse train. To maintain a high machining quality i.e. minimum surface roughness, the pulse-to-pulse distance has also to be optimized. Highest ablation efficiency is obtained by choosing the proper laser peak fluence together with highest specific removal rate. The throughput can now be enhanced by simultaneously increasing the average power, the repetition rate as well as the scanning speed to preserve the fluence and the pulse-to-pulse distance. Therefore a high scanning speed is of essential importance. To guarantee the required excellent accuracy even at high scanning speeds a new interferometry based encoder technology was used, that provides a high quality signal for closed-loop control of the galvo scanner position. Low inertia encoder design enables a very dynamic scanner system, which can be driven to very high line speeds by a specially adapted control solution. We will present results with marking speeds up to 25 m/s using a f = 100 mm objective obtained with a new scanning system and scanner tuning maintaining a precision of about 5 μm. Further it will be shown that, especially for short line lengths, the machining time can be minimized by choosing the proper speed which has not to be the maximum one.

  19. Fluorescence lifetime plate reader: resolution and precision meet high-throughput.

    PubMed

    Petersen, Karl J; Peterson, Kurt C; Muretta, Joseph M; Higgins, Sutton E; Gillispie, Gregory D; Thomas, David D

    2014-11-01

    We describe a nanosecond time-resolved fluorescence spectrometer that acquires fluorescence decay waveforms from each well of a 384-well microplate in 3 min with signal-to-noise exceeding 400 using direct waveform recording. The instrument combines high-energy pulsed laser sources (5-10 kHz repetition rate) with a photomultiplier and high-speed digitizer (1 GHz) to record a fluorescence decay waveform after each pulse. Waveforms acquired from rhodamine or 5-((2-aminoethyl)amino) naphthalene-1-sulfonic acid dyes in a 384-well plate gave lifetime measurements 5- to 25-fold more precise than the simultaneous intensity measurements. Lifetimes as short as 0.04 ns were acquired by interleaving with an effective sample rate of 5 GHz. Lifetime measurements resolved mixtures of single-exponential dyes with better than 1% accuracy. The fluorescence lifetime plate reader enables multiple-well fluorescence lifetime measurements with an acquisition time of 0.5 s per well, suitable for high-throughput fluorescence lifetime screening applications.

  20. THE APPLICATION OF MULTIVIEW METHODS FOR HIGH-PRECISION ASTROMETRIC SPACE VLBI AT LOW FREQUENCIES

    SciTech Connect

    Dodson, R.; Rioja, M.; Imai, H.; Asaki, Y.; Hong, X.-Y.; Shen, Z.

    2013-06-15

    High-precision astrometric space very long baseline interferometry (S-VLBI) at the low end of the conventional frequency range, i.e., 20 cm, is a requirement for a number of high-priority science goals. These are headlined by obtaining trigonometric parallax distances to pulsars in pulsar-black hole pairs and OH masers anywhere in the Milky Way and the Magellanic Clouds. We propose a solution for the most difficult technical problems in S-VLBI by the MultiView approach where multiple sources, separated by several degrees on the sky, are observed simultaneously. We simulated a number of challenging S-VLBI configurations, with orbit errors up to 8 m in size and with ionospheric atmospheres consistent with poor conditions. In these simulations we performed MultiView analysis to achieve the required science goals. This approach removes the need for beam switching requiring a Control Moment Gyro, and the space and ground infrastructure required for high-quality orbit reconstruction of a space-based radio telescope. This will dramatically reduce the complexity of S-VLBI missions which implement the phase-referencing technique.

  1. Study of Optical Mode Scrambling of Fiber Optics for High Precision Radial Velocity Measurements

    NASA Astrophysics Data System (ADS)

    Cassette, Anthony; Ge, Jian; Jeram, Sarik; Klanot, Khaya; Ma, Bo; Varosi, Frank

    2016-01-01

    Optical Fibers have been used throughout Astronomy for spectroscopy with spectrographs located some distance away from the telescope. This fiber-fed design has greatly increased precision for radial velocity (RV) measurements. However, due to the incomplete fiber illumination mode scrambling in the radial direction, high resolution spectrographs with regular circular fibers have suffered RV uncertainties on the order of a few to tens of m/s with stellar observations, which largely limited their sensitivity in detecting and characterizing low mass planets around stars. At the University of Florida, we studied mode scrambling gain of a few different optical devices, such as three-lens optical double scramblers, octagonal fibers and low numerical aperture fibers with a goal to find an optimal mode scrambling solution for the TOU optical very high resolution spectrograph (R=100,000, 0.38-0.9 microns) and FIRST near infrared high resolution spectrograph (R=60,000, 0.9-1.8 microns) for the on-going Dharma Planet Survey. This presentation will report our lab measurement results and also stellar RV measurements at the observatories.

  2. 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.

  3. Measuring High-Precision Astrometry with the Infrared Array Camera on the Spitzer Space Telescope

    NASA Astrophysics Data System (ADS)

    Esplin, T. L.; Luhman, K. L.

    2016-01-01

    The Infrared Array Camera (IRAC) on the Spitzer Space Telescope currently offers the greatest potential for high-precision astrometry of faint mid-IR sources across arcminute-scale fields, which would be especially valuable for measuring parallaxes of cold brown dwarfs in the solar neighborhood and proper motions of obscured members of nearby star-forming regions. To more fully realize IRAC's astrometric capabilities, we have sought to minimize the largest sources of uncertainty in astrometry with its 3.6 and 4.5 μm bands. By comparing different routines that estimate stellar positions, we have found that Point Response Function (PRF) fitting with the Spitzer Science Center's Astronomical Point Source Extractor produces both the smallest systematic errors from varying intra-pixel sensitivity and the greatest precision in measurements of positions. In addition, self-calibration has been used to derive new 7th and 8th order distortion corrections for the 3.6 and 4.5 μm arrays of IRAC, respectively. These corrections are suitable for data throughout the mission of Spitzer when a time-dependent scale factor is applied to the corrections. To illustrate the astrometric accuracy that can be achieved by combining PRF fitting with our new distortion corrections, we have applied them to archival data for a nearby star-forming region, arriving at total astrometric errors of ∼20 and 70 mas at signal to noise ratios of 100 and 10, respectively. Based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA.

  4. COROT-high-precision stellar photometry on a low Earth orbit: solutions to minimize environmental perturbations

    NASA Astrophysics Data System (ADS)

    Auvergne, Michel; Boisnard, Laurent; Buey, Jean-Tristan M.; Epstein, Gerard; Hustaix, Herve; Jouret, Martine; Levacher, Patrick; Berrivin, Stephane; Baglin, Annie

    2003-02-01

    The COROT small satellite project is a space mission dedicated to stellar seismology and search for telluric extra-solar planets. For the two programs a very high photometric precision is needed. The COROT seismology program will measure periodic variations with amplitude of 2.10-6 of the photon flux emitted by bright stars. COROT will also be able to detect the presence of exoplanets when they pass between the satellite and their parent star. Modifying both the integration time and the focus conditions, it allows to detect photons flux variations about 7.10-4 in one hour integration, compatible with an occultation detection on a very large number of stars (magnitude between 12 and 15.5). Between 10 and 40 telluric planets in the "habitable zone" and several hundreds of hot Jupiters should be detected depending on hypotheses about planets existence. To reach the required performances a stringent instrument stability is necessary. The satellite Preliminary Design Review will be held in November 2002 while the instrument is already in development phase for a delivery of the flight model in 2004. The launch is scheduled late 2005, by the first SOYUZ launcher to fly from the Guyana Space Center. The project activities are currently focused on the instrument and system engineering. Straylight rejection, pointing, thermal stability are the main critical points of the mission, on a LEO at 826 kms, for which cost-effective compromises have been found to 1mit their effects. This paper recalls the scientific program s, the main characteristics of the mission, describes the impact of the three main perturbators on the photometric precision and the technical solutions which reduce their contribution at an acceptable level.

  5. Project GeoWSN: High precision but low-cost GNSS landslide monitoring in Austria

    NASA Astrophysics Data System (ADS)

    Koch, Daniel; Brandstätter, Michael; Kühtreiber, Norbert

    2014-05-01

    At present, GNSS monitoring of landslides is an accepted and approved method to detect movements of slopes at risk in the sub-centimetre level. However, high-precision geodetic GNSS-receivers are expensive, therefore this monitoring method is not widely applied. Recently low-cost GNSS-receivers are conquering the geodetic market and are well suited for a cost effective and yet precise GNSS-monitoring. During the project GeoWSN, which was funded by the Austrian Research Promotion Agency (FFG), an applicable low-cost monitoring system was developed at Graz University of Technology. The system is based on a so-called Wireless Sensor Network (WSN) consisting of low-cost GNSS-receivers, temperature and humidity sensors and inertial measurement units. Additionally energy-harvesting technologies and power-saving algorithms provide that the system is energy- autarkic. For real-time applications, a communication link between the sensor nodes is implemented. The relative positioning method RTK (Real Time Kinematic) is applied to reach the highest possible accuracy. The GeoWSN sensor nodes enable the detection of possible movements in the real-time processed positions of the sensor nodes. To ensure a real-time evaluation and interpretation of the data, the current status of the slope can be acquired by a local warning centre. Therefore, affected people can be warned within a short latency. Several test-scenarios have shown the acceptance of the system at the warning centre of Styria, Austria. This contribution should give an overview of the main idea of a low-cost warning system and results of the project GeoWSN.

  6. High Precision, Directly Determined Radii and Effective Temperatures for Giant Stars

    NASA Astrophysics Data System (ADS)

    van Belle, Gerard

    have demonstrated the potential of all aspects of this program, and through the proposed effort will unify the diverse components to study these giants. A homogenous catalog of linear radii and effective temperatures for hundreds of giants will be generated, which in turn will be used to calibrate radius and temperature scales for application to the broad population of giants. Significance. Fundamental temperature and radius scales are used throughout stellar astrophysics, including stellar structure studies, stellar modeling, galactic spectral synthesis, planet detection studies, and star formation theory. We expect to reduce the error in effective temperature calibration by 2-4x, and the error in linear radius by 2-3x or more. A high- precision improvement to these scales will, in turn, broadly advance a wide swath of studies that depend on precisely knowing the radii and temperature of stars. This proposal aims to produce the definitive linear radius and effective temperature scales for giants. A significant improvement in the determinations of the radii and effective temperatures of giant stars across the HR diagram will have far reaching consequences across the broad expanse of astrophysical research. Relevance to NASA. High-precision calibrations of temperature scales are essential to flux calibrations of past and ongoing NASA science satellite observations, such as those from Spitzer and WISE, and a significantly improved linear radius reference markedly improves Kepler discoveries in both the exoplanet and asteroseismology areas. In addition to the high scientific potential of this program, it also provides technical benefits by furthering interferometric techniques that will be critical for future high angular resolution astronomy.

  7. Impact evaluation of environmental and geometrical parasitic effects on high-precision position measurement of the LHC collimator jaws

    NASA Astrophysics Data System (ADS)

    Danisi, Alessandro; Losito, Roberto; Masi, Alessandro

    2015-09-01

    Measuring the apertures of the Large Hadron Collider (LHC) collimators, as well as the positions of their axes, is a challenging task. The LHC collimators are equipped with high-precision linear position sensors, the linear variable differential transformers (LVDTs). The accuracy of such sensors is limited by the peculiar parasitic effect of being rather sensitive to external magnetic fields. A new type of inductive sensor, the Ironless Inductive Position Sensor (I2PS), that keeps the advantages of the LVDTs but is insensitive to external magnetic fields has been designed, constructed, and tested at CERN. For this sensor, a detailed description of parasitic effects such as high-frequency capacitances and the presence of conductive shields and electric motor, in the surroundings is given, from analytical, numerical, and experimental viewpoints. In addition, proof is given of the I2PS’s radiation hardness. The aim of this paper is to give a complete and exhaustive impact evaluation, from the metrological viewpoint, of these parasitic effects on these two fundamental sensor solutions.

  8. Precision interferometric measurements of mirror birefringence in high-finesse optical resonators

    NASA Astrophysics Data System (ADS)

    Fleisher, Adam J.; Long, David A.; Liu, Qingnan; Hodges, Joseph T.

    2016-01-01

    High-finesse optical resonators found in ultrasensitive laser spectrometers utilize supermirrors ideally consisting of isotropic high-reflectivity coatings. Strictly speaking, however, the optical coatings are often nonuniformly stressed during the deposition process and therefore do possess some small amount of birefringence. When physically mounted the cavity mirrors can be additionally stressed in such a way that large optical birefringence is induced. Here we report a direct measurement of optical birefringence in a two-mirror Fabry-Pérot cavity with R =99.99 % by observing TEM00 mode beating during cavity decays. Experiments were performed at a wavelength of 4.53 μ m , with precision limited by both quantum and technical noise sources. We report a splitting of δν=618 (1 ) Hz, significantly less than the intrinsic cavity line width of δcav≈3 kHz. With a cavity free spectral range of 96.9 MHz, the equivalent fractional change in mirror refractive index due to birefringence is therefore Δ n /n =6.38 (1 ) ×10-6 .

  9. A high precision phase reconstruction algorithm for multi-laser guide stars adaptive optics

    NASA Astrophysics Data System (ADS)

    He, Bin; Hu, Li-Fa; Li, Da-Yu; Xu, Huan-Yu; Zhang, Xing-Yun; Wang, Shao-Xin; Wang, Yu-Kun; Yang, Cheng-Liang; Cao, Zhao-Liang; Mu, Quan-Quan; Lu, Xing-Hai; Xuan, Li

    2016-09-01

    Adaptive optics (AO) systems are widespread and considered as an essential part of any large aperture telescope for obtaining a high resolution imaging at present. To enlarge the imaging field of view (FOV), multi-laser guide stars (LGSs) are currently being investigated and used for the large aperture optical telescopes. LGS measurement is necessary and pivotal to obtain the cumulative phase distortion along a target in the multi-LGSs AO system. We propose a high precision phase reconstruction algorithm to estimate the phase for a target with an uncertain turbulence profile based on the interpolation. By comparing with the conventional average method, the proposed method reduces the root mean square (RMS) error from 130 nm to 85 nm with a 30% reduction for narrow FOV. We confirm that such phase reconstruction algorithm is validated for both narrow field AO and wide field AO. Project supported by the National Natural Science Foundation of China (Grant Nos. 11174274, 11174279, 61205021, 11204299, 61475152, and 61405194) and State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences.

  10. The Spring 1985 high precision baseline test of the JPL GPS-based geodetic system

    NASA Technical Reports Server (NTRS)

    Davidson, John M.; Thornton, Catherine L.; Stephens, Scott A.; Blewitt, Geoffrey; Lichten, Stephen M.; Sovers, Ojars J.; Kroger, Peter M.; Skrumeda, Lisa L.; Border, James S.; Neilan, Ruth E.

    1987-01-01

    The Spring 1985 High Precision Baseline Test (HPBT) was conducted. The HPBT was designed to meet a number of objectives. Foremost among these was the demonstration of a level of accuracy of 1 to 2:10 to the 7th power, or better, for baselines ranging in length up to several hundred kilometers. These objectives were all met with a high degree of success, with respect to the demonstration of system accuracy in particular. The results from six baselines ranging in length from 70 to 729 km were examined for repeatability and, in the case of three baselines, were compared to results from colocated VLBI systems. Repeatability was found to be 5:10 to the 8th power (RMS) for the north baseline coordinate, independent of baseline length, while for the east coordinate RMS repeatability was found to be larger than this by factors of 2 to 4. The GPS-based results were found to be in agreement with those from colocated VLBI measurements, when corrected for the physical separations of the VLBI and CPG antennas, at the level of 1 to 2:10 to the 7th power in all coordinates, independent of baseline length. The results for baseline repeatability are consistent with the current GPA error budget, but the GPS-VLBI intercomparisons disagree at a somewhat larger level than expected. It is hypothesized that these differences may result from errors in the local survey measurements used to correct for the separations of the GPS and VLBI antenna reference centers.

  11. Frontend electronics for high-precision single photo-electron timing using FPGA-TDCs

    NASA Astrophysics Data System (ADS)

    Cardinali, M.; Dzyhgadlo, R.; Gerhardt, A.; Götzen, K.; Hohler, R.; Kalicy, G.; Kumawat, H.; Lehmann, D.; Lewandowski, B.; Patsyuk, M.; Peters, K.; Schepers, G.; Schmitt, L.; Schwarz, C.; Schwiening, J.; Traxler, M.; Ugur, C.; Zühlsdorf, M.; Dodokhov, V. Kh.; Britting, A.; Eyrich, W.; Lehmann, A.; Uhlig, F.; Düren, M.; Föhl, K.; Hayrapetyan, A.; Kröck, B.; Merle, O.; Rieke, J.; Cowie, E.; Keri, T.; Montgomery, R.; Rosner, G.; Achenbach, P.; Corell, O.; Ferretti Bondy, M. I.; Hoek, M.; Lauth, W.; Rosner, C.; Sfienti, C.; Thiel, M.; Bühler, P.; Gruber, L.; Marton, J.; Suzuki, K.

    2014-12-01

    The next generation of high-luminosity experiments requires excellent particle identification detectors which calls for Imaging Cherenkov counters with fast electronics to cope with the expected hit rates. A Barrel DIRC will be used in the central region of the Target Spectrometer of the planned PANDA experiment at FAIR. A single photo-electron timing resolution of better than 100 ps is required by the Barrel DIRC to disentangle the complicated patterns created on the image plane. R&D studies have been performed to provide a design based on the TRB3 readout using FPGA-TDCs with a precision better than 20 ps RMS and custom frontend electronics with high-bandwidth pre-amplifiers and fast discriminators. The discriminators also provide time-over-threshold information thus enabling walk corrections to improve the timing resolution. Two types of frontend electronics cards optimised for reading out 64-channel PHOTONIS Planacon MCP-PMTs were tested: one based on the NINO ASIC and the other, called PADIWA, on FPGA discriminators. Promising results were obtained in a full characterisation using a fast laser setup and in a test experiment at MAMI, Mainz, with a small scale DIRC prototype.

  12. Precision Interferometric Measurements of Mirror Birefringence in High-Finesse Optical Resonators

    PubMed Central

    Fleisher, Adam J.; Long, David A.; Liu, Qingnan; Hodges, Joseph T.

    2016-01-01

    High-finesse optical resonators found in ultrasensitive laser spectrometers utilize supermirrors ideally consisting of isotropic high-reflectivity coatings. Strictly speaking, however, the optical coatings are often non-uniformly stressed during the deposition process and therefore do possess some small amount of birefringence. When physically mounted the cavity mirrors can be additionally stressed in such a way that large optical birefringence is induced. Here we report a direct measurement of optical birefringence in a two-mirror Fabry-Pérot cavity with R = 99.99 % by observing TEM00 mode beating during cavity decays. Experiments were performed at a wavelength of 4.53 μm, with precision limited by both quantum and technical noise sources. We report a splitting of δν = 618(1) Hz, significantly less than the intrinsic cavity linewidth of δcav ≈ 3 kHz. With a cavity free spectral range of 96.9 MHz, the equivalent fractional change in mirror refractive index due to birefringence is therefore Δn/n = 6.38(1) × 10−6. PMID:27088133

  13. High precision landing site mapping and rover localization for Chang'e-3 mission

    NASA Astrophysics Data System (ADS)

    Liu, ZhaoQin; Di, KaiChang; Peng, Man; Wan, WenHui; Liu, Bin; Li, LiChun; Yu, TianYi; Wang, BaoFeng; Zhou, JianLiang; Chen, HongMin

    2015-01-01

    This paper presents the comprehensive results of landing site topographic mapping and rover localization in Chang'e-3 mission. High-precision topographic products of the landing site with extremely high resolutions (up to 0.05 m) were generated from descent images and registered to CE-2 DOM. Local DEM and DOM with 0.02 m resolution were produced routinely at each waypoint along the rover traverse. The lander location was determined to be (19.51256°W, 44.11884°N, -2615.451 m) using a method of DOM matching. In order to reduce error accumulation caused by wheel slippage and IMU drift in dead reckoning, cross-site visual localization and DOM matching localization methods were developed to localize the rover at waypoints; the overall traveled distance from the lander is 114.8 m from cross-site visual localization and 111.2 m from DOM matching localization. The latter is of highest accuracy and has been verified using a LRO NAC image where the rover trajeactory is directly identifiable. During CE-3 mission operations, landing site mapping and rover localization products including DEMs and DOMs, traverse maps, vertical traverse profiles were generated timely to support teleoperation tasks such as obstacle avoidance and rover path planning.

  14. A high precision phase reconstruction algorithm for multi-laser guide stars adaptive optics

    NASA Astrophysics Data System (ADS)

    He, Bin; Hu, Li-Fa; Li, Da-Yu; Xu, Huan-Yu; Zhang, Xing-Yun; Wang, Shao-Xin; Wang, Yu-Kun; Yang, Cheng-Liang; Cao, Zhao-Liang; Mu, Quan-Quan; Lu, Xing-Hai; Xuan, Li

    2016-09-01

    Adaptive optics (AO) systems are widespread and considered as an essential part of any large aperture telescope for obtaining a high resolution imaging at present. To enlarge the imaging field of view (FOV), multi-laser guide stars (LGSs) are currently being investigated and used for the large aperture optical telescopes. LGS measurement is necessary and pivotal to obtain the cumulative phase distortion along a target in the multi-LGSs AO system. We propose a high precision phase reconstruction algorithm to estimate the phase for a target with an uncertain turbulence profile based on the interpolation. By comparing with the conventional average method, the proposed method reduces the root mean square (RMS) error from 130 nm to 85 nm with a 30% reduction for narrow FOV. We confirm that such phase reconstruction algorithm is validated for both narrow field AO and wide field AO. Project supported by the National Natural Science Foundation of China (Grant Nos. 11174274, 11174279, 61205021, 11204299, 61475152, and 61405194) and State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences.

  15. High-Precision Temperature Control of a Crystal Growth Furnace at 1,500 C

    NASA Technical Reports Server (NTRS)

    Stenzel, Ch.; Hess, A.; Croell, A.; Breuer, D.; Sauermann, H.

    2012-01-01

    For crystal growth of semiconductor materials a short-term temperature stability of 0.1 C at 1500 C is one of the essential parameters to be addressed for achieving high-quality crystals. Hence, for temperature monitoring and control with high precision in a floating zone furnace two sets of thermo-sensors, type B thermocouples and optical fibre thermometers, have been implemented and successfully operated in the furnace for more than 2000 h. The optical fibre thermometers consist of an optical system made of sapphire (two fibres plus a prism in between for deflection) and transmit the infra-red radiation of the heater to the outside of the hot core of the furnace for pyrometric temperature measurement. A dedicated control algorithm has been set up which controlled the power settings to the individual heaters. Both sensor types showed no degradation after this period and yielded a short-term stability at 1200 C of 0.05 C (optical fibre thermometers), respectively 0.08 C (thermocouples).

  16. High-precision topography measurement through accurate in-focus plane detection with hybrid digital holographic microscope and white light interferometer module.

    PubMed

    Liżewski, Kamil; Tomczewski, Sławomir; Kozacki, Tomasz; Kostencka, Julianna

    2014-04-10

    High-precision topography measurement of micro-objects using interferometric and holographic techniques can be realized provided that the in-focus plane of an imaging system is very accurately determined. Therefore, in this paper we propose an accurate technique for in-focus plane determination, which is based on coherent and incoherent light. The proposed method consists of two major steps. First, a calibration of the imaging system with an amplitude object is performed with a common autofocusing method using coherent illumination, which allows for accurate localization of the in-focus plane position. In the second step, the position of the detected in-focus plane with respect to the imaging system is measured with white light interferometry. The obtained distance is used to accurately adjust a sample with the precision required for the measurement. The experimental validation of the proposed method is given for measurement of high-numerical-aperture microlenses with subwavelength accuracy.

  17. 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.

  18. A lane-level LBS system for vehicle network with high-precision BDS/GPS positioning.

    PubMed

    Guo, Chi; Guo, Wenfei; Cao, Guangyi; Dong, Hongbo

    2015-01-01

    In recent years, research on vehicle network location service has begun to focus on its intelligence and precision. The accuracy of space-time information has become a core factor for vehicle network systems in a mobile environment. However, difficulties persist in vehicle satellite positioning since deficiencies in the provision of high-quality space-time references greatly limit the development and application of vehicle networks. In this paper, we propose a high-precision-based vehicle network location service to solve this problem. The major components of this study include the following: (1) application of wide-area precise positioning technology to the vehicle network system. An adaptive correction message broadcast protocol is designed to satisfy the requirements for large-scale target precise positioning in the mobile Internet environment; (2) development of a concurrence service system with a flexible virtual expansion architecture to guarantee reliable data interaction between vehicles and the background; (3) verification of the positioning precision and service quality in the urban environment. Based on this high-precision positioning service platform, a lane-level location service is designed to solve a typical traffic safety problem. PMID:25755665

  19. A lane-level LBS system for vehicle network with high-precision BDS/GPS positioning.

    PubMed

    Guo, Chi; Guo, Wenfei; Cao, Guangyi; Dong, Hongbo

    2015-01-01

    In recent years, research on vehicle network location service has begun to focus on its intelligence and precision. The accuracy of space-time information has become a core factor for vehicle network systems in a mobile environment. However, difficulties persist in vehicle satellite positioning since deficiencies in the provision of high-quality space-time references greatly limit the development and application of vehicle networks. In this paper, we propose a high-precision-based vehicle network location service to solve this problem. The major components of this study include the following: (1) application of wide-area precise positioning technology to the vehicle network system. An adaptive correction message broadcast protocol is designed to satisfy the requirements for large-scale target precise positioning in the mobile Internet environment; (2) development of a concurrence service system with a flexible virtual expansion architecture to guarantee reliable data interaction between vehicles and the background; (3) verification of the positioning precision and service quality in the urban environment. Based on this high-precision positioning service platform, a lane-level location service is designed to solve a typical traffic safety problem.

  20. A Lane-Level LBS System for Vehicle Network with High-Precision BDS/GPS Positioning

    PubMed Central

    Guo, Chi; Guo, Wenfei; Cao, Guangyi; Dong, Hongbo

    2015-01-01

    In recent years, research on vehicle network location service has begun to focus on its intelligence and precision. The accuracy of space-time information has become a core factor for vehicle network systems in a mobile environment. However, difficulties persist in vehicle satellite positioning since deficiencies in the provision of high-quality space-time references greatly limit the development and application of vehicle networks. In this paper, we propose a high-precision-based vehicle network location service to solve this problem. The major components of this study include the following: (1) application of wide-area precise positioning technology to the vehicle network system. An adaptive correction message broadcast protocol is designed to satisfy the requirements for large-scale target precise positioning in the mobile Internet environment; (2) development of a concurrence service system with a flexible virtual expansion architecture to guarantee reliable data interaction between vehicles and the background; (3) verification of the positioning precision and service quality in the urban environment. Based on this high-precision positioning service platform, a lane-level location service is designed to solve a typical traffic safety problem. PMID:25755665

  1. High precision during food recruitment of experienced (reactivated) foragers in the stingless bee Scaptotrigona mexicana (Apidae, Meliponini)

    NASA Astrophysics Data System (ADS)

    Sánchez, Daniel; Nieh, James C.; Hénaut, Yann; Cruz, Leopoldo; Vandame, Rémy

    Several studies have examined the existence of recruitment communication mechanisms in stingless bees. However, the spatial accuracy of location-specific recruitment has not been examined. Moreover, the location-specific recruitment of reactivated foragers, i.e., foragers that have previously experienced the same food source at a different location and time, has not been explicitly examined. However, such foragers may also play a significant role in colony foraging, particularly in small colonies. Here we report that reactivated Scaptotrigona mexicana foragers can recruit with high precision to a specific food location. The recruitment precision of reactivated foragers was evaluated by placing control feeders to the left and the right of the training feeder (direction-precision tests) and between the nest and the training feeder and beyond it (distance-precision tests). Reactivated foragers arrived at the correct location with high precision: 98.44% arrived at the training feeder in the direction trials (five-feeder fan-shaped array, accuracy of at least +/-6° of azimuth at 50 m from the nest), and 88.62% arrived at the training feeder in the distance trials (five-feeder linear array, accuracy of at least +/-5 m or +/-10% at 50 m from the nest). Thus, S. mexicana reactivated foragers can find the indicated food source at a specific distance and direction with high precision, higher than that shown by honeybees, Apis mellifera, which do not communicate food location at such close distances to the nest.

  2. High precision multi-genome scale reannotation of enzyme function by EFICAz

    PubMed Central

    Arakaki, Adrian K; Tian, Weidong; Skolnick, Jeffrey

    2006-01-01

    Background The functional annotation of most genes in newly sequenced genomes is inferred from similarity to previously characterized sequences, an annotation strategy that often leads to erroneous assignments. We have performed a reannotation of 245 genomes using an updated version of EFICAz, a highly precise method for enzyme function prediction. Results Based on our three-field EC number predictions, we have obtained lower-bound estimates for the average enzyme content in Archaea (29%), Bacteria (30%) and Eukarya (18%). Most annotations added in KEGG from 2005 to 2006 agree with EFICAz predictions made in 2005. The coverage of EFICAz predictions is significantly higher than that of KEGG, especially for eukaryotes. Thousands of our novel predictions correspond to hypothetical proteins. We have identified a subset of 64 hypothetical proteins with low sequence identity to EFICAz training enzymes, whose biochemical functions have been recently characterized and find that in 96% (84%) of the cases we correctly identified their three-field (four-field) EC numbers. For two of the 64 hypothetical proteins: PA1167 from Pseudomonas aeruginosa, an alginate lyase (EC 4.2.2.3) and Rv1700 of Mycobacterium tuberculosis H37Rv, an ADP-ribose diphosphatase (EC 3.6.1.13), we have detected annotation lag of more than two years in databases. Two examples are presented where EFICAz predictions act as hypothesis generators for understanding the functional roles of hypothetical proteins: FLJ11151, a human protein overexpressed in cancer that EFICAz identifies as an endopolyphosphatase (EC 3.6.1.10), and MW0119, a protein of Staphylococcus aureus strain MW2 that we propose as candidate virulence factor based on its EFICAz predicted activity, sphingomyelin phosphodiesterase (EC 3.1.4.12). Conclusion Our results suggest that we have generated enzyme function annotations of high precision and recall. These predictions can be mined and correlated with other information sources to generate

  3. High-precision (143)Nd/(144)Nd ratios from NdO(+) data corrected with in-run measured oxygen isotope ratios.

    PubMed

    Chu, Zhu-Yin; Li, Chao-Feng; Hegner, Ernst; Chen, Zhi; Yan, Yan; Guo, Jing-Hui

    2014-11-18

    The NdO(+) technique has been considerably refined in recent years for high-precision measurement of Nd isotope ratios in low-level samples (1-5 ng Nd). As oxygen isotopic compositions may vary significantly with experimental conditions such as filament material, ionization enhancer and the ambient oxygen in the ion source, great "care" should be taken for using correct oxygen isotopic compositions to do the isobaric oxide corrections for the "conventional" NdO(+) method. Our method presented here for NdO(+) data reduction and PrO(+) interference corrections uses the oxygen isotope composition determined in each cycle of the NdO(+) measurements. For that purpose, we measured the small ion signals of (150)Nd(17)O(+) and (150)Nd(18)O(+) with amplifiers equipped with 10(12) Ω feedback resistors, and those of Nd(16)O(+) ion beams with 10(11) Ω amplifiers. Using 10(12) Ω amplifiers facilitates a precise measurement of the very small (150)Nd(17)O(+) and (150)Nd(18)O(+) ion signals and calculation of highly accurate and precise (143)Nd/(144)Nd isotope ratios. The (143)Nd/(144)Nd ratios for JNdi-1 standards and several whole-rock reference materials determined with the method on 4 ng of Nd loads are consistent with previously reported values within analytical error, with internal and external precision (2 RSE and 2 RSD) of better than 20 and 30 ppm, respectively.

  4. The high throughput biomedicine unit at the institute for molecular medicine Finland: high throughput screening meets precision medicine.

    PubMed

    Pietiainen, Vilja; Saarela, Jani; von Schantz, Carina; Turunen, Laura; Ostling, Paivi; Wennerberg, Krister

    2014-05-01

    The High Throughput Biomedicine (HTB) unit at the Institute for Molecular Medicine Finland FIMM was established in 2010 to serve as a national and international academic screening unit providing access to state of the art instrumentation for chemical and RNAi-based high throughput screening. The initial focus of the unit was multiwell plate based chemical screening and high content microarray-based siRNA screening. However, over the first four years of operation, the unit has moved to a more flexible service platform where both chemical and siRNA screening is performed at different scales primarily in multiwell plate-based assays with a wide range of readout possibilities with a focus on ultraminiaturization to allow for affordable screening for the academic users. In addition to high throughput screening, the equipment of the unit is also used to support miniaturized, multiplexed and high throughput applications for other types of research such as genomics, sequencing and biobanking operations. Importantly, with the translational research goals at FIMM, an increasing part of the operations at the HTB unit is being focused on high throughput systems biological platforms for functional profiling of patient cells in personalized and precision medicine projects.

  5. Progress in Bathymetric Surveys: Combining High Precision Positioning in Real Time with a Continuous Vertical Datum in Remote Areas

    NASA Astrophysics Data System (ADS)

    Lévesque, S.; Robin, C. M. I.; MacLeod, K.; Fadaie, K.

    2014-12-01

    For most of its bathymetric survey activities, the Canadian Hydrographic Service (CHS) requires high precision, three dimensional positioning. As part of a pilot project, one of its launches was equipped with a GNSS receiver processing a high precision correction service in real time (HP-GPS*C) via the internet using satellite telecommunication. This service was provided by Natural Resources Canada/Canadian Geodetic Survey (NRCan/CGS). The bathymetric data from a survey in eastern Hudson Bay performed by CHS in Fall 2013 was post -processed using different standard methods. This resulted in high precision positions that were compared with positions corrected with the real-time precise point positioning (PPP) service (HP-GPS*C) from NRCan/CGS. CHS bathymetric surveys must be referred to chart datum, the hydrographical vertical datum defined for use on nautical charts. In the Canadian north, another limitation to high precision bathymetric work is the availability of tide observations and/or predictions. The territory is vast and tide data is limited in space and in time while predicted tides are not always accurate. This makes reductions of bathymetric soundings to Chart datum difficult. To address this problem, CHS and NRCan/CGS have collaborated to produce a Continuous Vertical Datum for Canadian Waters (CVDCW), which incorporates data from NRCan's geoid model, tide gauge and GPS data, satellite altimetry, and ocean models. Thus high precision positioning provides ellipsoidal heights for the bathymetric depths, and the CVDCW allows to correct these ellipsoidal heights to chart datum. Comparisons of the bathymetry from the pilot survey corrected for tide data versus the bathymetry referred to its ellipsoidal height corrected to chart datum with the CVDCW are given to demonstrate the relative changes to the depths. This also illustrates the advantage of a continuous vertical datum with its potential to be combined with real-time high precision positioning.

  6. Acceleration feedback control (AFC) enhanced by disturbance observation and compensation (DOC) for high precision tracking in telescope systems

    NASA Astrophysics Data System (ADS)

    Wang, Qiang; Cai, Hua-Xiang; Huang, Yong-Mei; Ge, Liang; Tang, Tao; Su, Yan-Rui; Liu, Xiang; Li, Jin-Ying; He, Dong; Du, Sheng-Ping; Ling, Yu

    2016-08-01

    In this paper, a cascade acceleration feedback control (AFC) enhanced by a disturbance observation and compensation (DOC) method is proposed to improve the tracking precision of telescope systems. Telescope systems usually suffer some uncertain disturbances, such as wind load, nonlinear friction and other unknown disturbances. To ensure tracking precision, an acceleration feedback loop which can increase the stiffness of such a system is introduced. Moreover, to further improve the tracking precision, we introduce the DOC method which can accurately estimate the disturbance and compensate it. Furthermore, the analysis of tracking accuracy used by this method is proposed. Finally, a few comparative experimental results show that the proposed control method has excellent performance for reducing the tracking error of a telescope system.

  7. High-precision mapping of seismicity in the 2014 Bárdarbunga volcanic episode

    NASA Astrophysics Data System (ADS)

    Vogfjörd, Kristín S.; Hensch, Martin; Gudmundsson, Gunnar B.; Jónsdóttir, Kristín

    2015-04-01

    The Bárdarbunga volcano and its associated fissure swarm in Iceland's Eastern volcanic zone is a highly active system with over 20 eruptions in the last 11 centuries. The location of this active volcano and much of the fissure swarm under several hundred metres thick ice gives rise to multiple hazards, including explosive, subglacial eruptions and associated subglacial floods (jökulhlaups), as well as fissure eruptions extruding large volumes of lava. After a decade of increasing seismic activity, volcanic unrest at Bárdarbunga suddenly escalated into a minor subglacial eruption on 16 August 2014. In the following weeks seismic activity soared and surface deformation of tens of cm were observed, caused by rifting and a dyke intrusion, which propagated 48 km northward from the central volcano (Sigmundsson et al., 2014). The dyke propagation stopped just outside the glacial margin and ended in a fissure eruption at Holuhraun at the end of August. At the time of writing the eruption is ongoing, having extruded a lava volume of over 1 km3 and released high rates of SO2 into the atmosphere. Over twenty thousand microearthquakes have been recorded. Initially most were in the dyke, but after the first two weeks the activity around the caldera rim increased and over 70 shallow earthquakes with MW > 5 have been located along the caldera rim accompanied by caldera subsidence. At the onset of the unrest on 16 August, the seismicity was located in the caldera and north of the caldera rim, but already in the first few hours the activity propagated out of the caldera to the SE. Still, the activity continued for a few days in the fissure swarm to the NE of the rim. High-precision earthquake locations in the propagating dyke have revealed its very detailed, planar rifting segments, with the events distributed over a 3-4 km depth range, and mostly between 6 and 9 km. These very planar event distributions are highly unusual in volcanic areas and strongly suggest rifting of

  8. Highly precise stabilization of intracavity prism-based Er:fiber frequency comb using optical-microwave phase detector.

    PubMed

    Zhang, Shuangyou; Wu, Jiutao; Leng, Jianxiao; Lai, Shunnan; Zhao, Jianye

    2014-11-15

    In this Letter, we demonstrate a fully stabilized Er:fiber frequency comb by using a fiber-based, high-precision optical-microwave phase detector. To achieve high-precision and long-term phase locking of the repetition rate to a microwave reference, frequency control techniques (tuning pump power and cavity length) are combined together as its feedback. Since the pump power has been used for stabilization of the repetition rate, we introduce a pair of intracavity prisms as a regulator for carrier-envelope offset frequency, thereby phase locking one mode of the comb to the rubidium saturated absorption transition line. The stabilized comb performs the same high stability as the reference for the repetition rate and provides a residual frequency instability of 3.6×10(-13) for each comb mode. The demonstrated stabilization scheme could provide a high-precision comb for optical communication, direct frequency comb spectroscopy.

  9. Precise reconstruction of fast moving cardiac valve in high frame rate synthetic transmit aperture ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Suzuki, Mayumi; Ikeda, Teiichiro; Ishihara, Chizue; Takano, Shinta; Masuzawa, Hiroshi

    2016-04-01

    To diagnose heart valve incompetence, i.e., one of the most serious cardiac dysfunctions, it is essential to obtain images of fast-moving valves at high spatial and temporal resolution. Ultrasound synthetic transmit aperture (STA) imaging has the potential to achieve high spatial resolution by synthesizing multiple pre-beamformed images obtained with corresponding multiple transmissions. However, applying STA to fast-moving targets is difficult due to serious target deformation. We propose a high-frame-rate STA (fast STA) imaging method that uses a reduced number of transmission events needed for each image. Fast STA is expected to suppress deformation of moving targets; however, it may result in deteriorated spatial resolution. In this study, we conducted a simulation study to evaluate fast STA. We quantitatively evaluated the reduction in deformation and deterioration of spatial resolution with a model involving a radially moving valve at the maximum speed of 0.5 m/s. The simulated raw channel data of the valve phantom was processed with offline beamforming programs. We compared B-mode images obtained through single received-line in a transmission (SRT) method, STA, and fast STA. The results show that fast STA with four-times-reduced events is superior in reconstructing the original shape of the moving valve to other methods. The accuracy of valve location is 97 and 100% better than those with SRT and STA, respectively. The resolution deterioration was found to be below the annoyance threshold considering the improved performance of the shape reconstruction. The obtained results are promising for providing more precise diagnostic information on cardiovascular diseases.

  10. Development of a micro-CMM with scanning touch probe and high-precision coplanar platform

    NASA Astrophysics Data System (ADS)

    Chu, Chih-Liang; Lu, Chin-Tu; Chen, Hung-Chi; Ke, Jhih-Sian; Chang, Chao-Ming

    2013-10-01

    This study develops a micro-CMM incorporating a scanning touch probe and a high-precision coplanar platform. The measurement performance of the proposed system was enhanced through the use of a rigid aluminum double-arch-bridge structure to support the scanning touch probe. For the working stage, a linear motor was used for long-stroke positioning and a piezoelectric actuator was then employed to fine-tune the positioning so as to achieve a requirement of highprecision. The platform has two characteristics: (i) the driving and measuring axes are designed along the same line so that Abbe error of the stage can be eliminated; (ii) the coplanar design makes the X and Y axes reach a goal of two-axis concurrent. The aforementioned two designs can reduce the error of the platform so that the micro-CMM reaches a positioning accuracy of ±0.1μm for a working volume of 80×80×40 mm3. Furthermore, the reliability of the probe mechanism of three degrees of freedom was analyzed and validated. The sensor coordinates a laser diode with Position Sensor Detectors (PSD) working with an optical path to measure placement of Z-axis and angle placement of XY-axis. By validation through an experiment, the three dimensional scanning touch probe developed by this study has a measuring range of ±1mm × ±1mm × 1mm with a unidirectional repeatability of 0.6μm.

  11. New high-precision 40Ar/39Ar ages on Oligocene volcanic rocks of northwestern Kenya

    NASA Astrophysics Data System (ADS)

    Brown, Francis H.; Jicha, Brian R.

    2016-02-01

    New, high-precision 40Ar/39Ar ages from volcanic rocks in northwestern Kenya are provided for some areas of exposure in this remote area. We report seven 40Ar/39Ar ages generated from single crystal total fusion experiments on alkali feldspar separated from volcanic rocks in the Mogila, Songot, and Lokwanamur Ranges and the Gatome valley. A rhyolite from the lower part of the sequence in the Mogila Range yielded ages of 32.31 ± 0.06 Ma and 32.33 ± 0.07 Ma, and a rhyolite near the top of that sequence yielded 31.67 ± 0.04 Ma. A single sample from the Songot Range yielded an age of 32.49 ± 0.07 Ma, slightly older than the rocks collected from Mogila. In both ranges the early Oligocene rhyolites are underlain by basalts, as is also the case in the Labur Range. Ages of 25.95 ± 0.03 Ma, 25.91 ± 0.04 Ma, and 27.15 ± 0.03 Ma were measured on alkali feldspar from rhyolites from the Lokwanamur Range, and the nearby Gatome valley. All of these rocks are part of an episode of widespread volcanism in northwestern Kenya in the mid-to late Oligocene that is not currently known from the Ethiopian Rift Valley.

  12. Study of fringe tracking for high-precision space-based interferometers

    NASA Astrophysics Data System (ADS)

    Padilla, Carlos E.; Karlov, Valeri I.; Li, Jun; Chun, Hon M.; Tsitsiklis, John N.; Reasenberg, Robert D.

    1995-06-01

    The purpose of the fringe tracking algorithms is to maintain lock on the target star after acquisition and to obtain the most accurate estimate possible of the scientific quantity (or quantities) of interest in the presence of dynamic disturbances to the spacecraft/interferometer ensemble. This study carries out an analysis of the performance and robustness achievable by four candidate estimation techniques when applied to an ultra-high-precision fringe tracking task (5 micro-arcsecond ultimate accuracy). The first class of fringe trackers studied include the Extended Kalman Filter. This class is followed by extensions to second and third order nonlinear filters developed by the authors. The higher order filters have expanded regions of convergence. Third, we consider the use of an invariant filter (IF) to estimate the angle between two target stars (using POINTS as a test case). The IF offers the advantage of improved robustness in the dynamical case, being in effect `invariant' to dynamics. Finally Discrete Bayes Algorithms make use of Bayes' decision rule to propagate the a posteriori distribution of the true parameter and take into account the discrete character of the Poisson photon arrival events. Variations of these algorithms, known as multiple hypotheses trackers, offer great promise for dim star tracking. An exploration of filter performance with respect to several parameters is carried out analytically and selected Monte Carlo simulations are carried out both to verify analytical predictions and to study performance.

  13. High-precision lead isotopes and stripy plumes: Revisiting the Society chain in French Polynesia

    NASA Astrophysics Data System (ADS)

    Cordier, Carole; Chauvel, Catherine; Hémond, Christophe

    2016-09-01

    An increasing number of geochemical studies looked for spatial organization of the isotopic variations along Pacific volcanic island chains (e.g., Hawaii, Marquesas, Samoa and Society Islands) in order to discuss the possible zoning of the plume conduits. Here, we reexamine the occurrence of isotopic stripes in the Society archipelago in French Polynesia, using new Sr-Nd-Hf-Pb isotope ratios of sixty-six lavas from six islands (Mehetia, Moorea, Maupiti, Huahine, Raiatea, Bora-Bora). We demonstrate that the Pb isotope variability observed using literature data is an analytical artifact related to the poor control of mass fractionation during Pb measurements by conventional TIMS technique. New MC-ICP-MS Pb data demonstrate that the isotopic stripes as previously defined disappear. They rather show that individual islands cover a significant part of the entire isotopic range of the chain. We suggest, therefore, that the dominant characteristic of the Society plume is small-scale heterogeneities, evenly distributed within the plume conduit. At a global scale, we show that some ocean island chains with similar geochemical and isotopic characteristics, such as Samoa and Society Islands, define different arrays when variations of Nd with high-precision Pb isotopes are considered. We proposed that this puzzling observation might record differences in recycling age of the basalt + sediment mixture subducted into the mantle and sampled by mantle plume.

  14. Stable isotope and high precision concentration measurements confirm that all humans produce and exhale methane.

    PubMed

    Keppler, Frank; Schiller, Amanda; Ehehalt, Robert; Greule, Markus; Hartmann, Jan; Polag, Daniela

    2016-01-29

    Mammalian formation of methane (methanogenesis) is widely considered to occur exclusively by anaerobic microbial activity in the gastrointestinal tract. Approximately one third of humans, depending on colonization of the gut by methanogenic archaea, are considered methane producers based on the classification terminology of high and low emitters. In this study laser absorption spectroscopy was used to precisely measure concentrations and stable carbon isotope signatures of exhaled methane in breath samples from 112 volunteers with an age range from 1 to 80 years. Here we provide analytical evidence that volunteers exhaled methane levels were significantly above background (inhaled) air. Furthermore, stable carbon isotope values of the exhaled methane unambiguously confirmed that this gas was produced by all of the human subjects studied. Based on the emission and stable carbon isotope patterns of various age groups we hypothesize that next to microbial sources in the gastrointestinal tracts there might be other, as yet unidentified, processes involved in methane formation supporting the idea that humans might also produce methane endogenously in cells. Finally we suggest that stable isotope measurements of volatile organic compounds such as methane might become a useful tool in future medical research diagnostic programs.

  15. Can we use high precision metal isotope analysis to improve our understanding of cancer?

    PubMed

    Larner, Fiona

    2016-01-01

    High precision natural isotope analyses are widely used in geosciences to trace elemental transport pathways. The use of this analytical tool is increasing in nutritional and disease-related research. In recent months, a number of groups have shown the potential this technique has in providing new observations for various cancers when applied to trace metal metabolism. The deconvolution of isotopic signatures, however, relies on mathematical models and geochemical data, which are not representative of the system under investigation. In addition to relevant biochemical studies of protein-metal isotopic interactions, technological development both in terms of sample throughput and detection sensitivity of these elements is now needed to translate this novel approach into a mainstream analytical tool. Following this, essential background healthy population studies must be performed, alongside observational, cross-sectional disease-based studies. Only then can the sensitivity and specificity of isotopic analyses be tested alongside currently employed methods, and important questions such as the influence of cancer heterogeneity and disease stage on isotopic signatures be addressed.

  16. High-precision branching-ratio measurement for the superallowed β+ emitter 74Rb

    NASA Astrophysics Data System (ADS)

    Dunlop, R.; Ball, G. C.; Leslie, J. R.; Svensson, C. E.; Towner, I. S.; Andreoiu, C.; Chagnon-Lessard, S.; Chester, A.; Cross, D. S.; Finlay, P.; Garnsworthy, A. B.; Garrett, P. E.; Glister, J.; Hackman, G.; Hadinia, B.; Leach, K. G.; Rand, E. T.; Starosta, K.; Tardiff, E. R.; Triambak, S.; Williams, S. J.; Wong, J.; Yates, S. W.; Zganjar, E. F.

    2013-10-01

    A high-precision branching-ratio measurement for the superallowed β+ decay of 74Rb was performed at the TRIUMF Isotope Separator and Accelerator (ISAC) radioactive ion-beam facility. The scintillating electron-positron tagging array (SCEPTAR), composed of 10 thin plastic scintillators, was used to detect the emitted β particles; the 8π spectrometer, an array of 20 Compton-suppressed HPGe detectors, was used for detecting γ rays that were emitted following Gamow-Teller and nonanalog Fermi β+ decays of 74Rb; and the Pentagonal Array of Conversion Electron Spectrometers (PACES), an array of 5 Si(Li) detectors, was employed for measuring β-delayed conversion electrons. Twenty-three excited states were identified in 74Kr following 8.241(4)×108 detected 74Rb β decays. A total of 58 γ-ray and electron transitions were placed in the decay scheme, allowing the superallowed branching ratio to be determined as B0=99.545(31)%. Combined with previous half-life and Q-value measurements, the superallowed branching ratio measured in this work leads to a superallowed ft value of 3082.8(65) s. Comparisons between this superallowed ft value and the world-average-corrected Ft¯ value, as well as the nonanalog Fermi branching ratios determined in this work, provide guidance for theoretical models of the isospin-symmetry-breaking corrections in this mass region.

  17. PRECISE HIGH-CADENCE TIME SERIES OBSERVATIONS OF FIVE VARIABLE YOUNG STARS IN AURIGA WITH MOST

    SciTech Connect

    Cody, Ann Marie; Tayar, Jamie; Hillenbrand, Lynne A.; Matthews, Jaymie M.; Kallinger, Thomas

    2013-03-15

    To explore young star variability on a large range of timescales, we have used the MOST satellite to obtain 24 days of continuous, sub-minute cadence, high-precision optical photometry on a field of classical and weak-lined T Tauri stars (TTSs) in the Taurus-Auriga star formation complex. Observations of AB Aurigae, SU Aurigae, V396 Aurigae, V397 Aurigae, and HD 31305 reveal brightness fluctuations at the 1%-10% level on timescales of hours to weeks. We have further assessed the variability properties with Fourier, wavelet, and autocorrelation techniques, identifying one significant period per star. We present spot models in an attempt to fit the periodicities, but find that we cannot fully account for the observed variability. Rather, all stars exhibit a mixture of periodic and aperiodic behavior, with the latter dominating stochastically on timescales less than several days. After removal of the main periodicity, periodograms for each light curve display power-law trends consistent with those seen for other young accreting stars. Several of our targets exhibited unusual variability patterns not anticipated by prior studies, and we propose that this behavior originates with the circumstellar disks. The MOST observations underscore the need for investigation of TTS light variations on a wide range of timescales in order to elucidate the physical processes responsible; we provide guidelines for future time series observations.

  18. Precision multidimensional assay for high-throughput microRNA drug discovery.

    PubMed

    Haefliger, Benjamin; Prochazka, Laura; Angelici, Bartolomeo; Benenson, Yaakov

    2016-01-01

    Development of drug discovery assays that combine high content with throughput is challenging. Information-processing gene networks can address this challenge by integrating multiple potential targets of drug candidates' activities into a small number of informative readouts, reporting simultaneously on specific and non-specific effects. Here we show a family of networks implementing this concept in a cell-based drug discovery assay for miRNA drug targets. The networks comprise multiple modules reporting on specific effects towards an intended miRNA target, together with non-specific effects on gene expression, off-target miRNAs and RNA interference pathway. We validate the assays using known perturbations of on- and off-target miRNAs, and evaluate an ∼700 compound library in an automated screen with a follow-up on specific and non-specific hits. We further customize and validate assays for additional drug targets and non-specific inputs. Our study offers a novel framework for precision drug discovery assays applicable to diverse target families. PMID:26880188

  19. A polynomial phase-shift algorithm for high precision three-dimensional profilometry

    NASA Astrophysics Data System (ADS)

    Deng, Fuqin; Liu, Chang; Sze, Wuifung; Deng, Jiangwen; Fung, Kenneth S. M.; Lam, Edmund Y.

    2013-03-01

    The perspective effect is common in real optical systems using projected patterns for machine vision applications. In the past, the frequencies of these sinusoidal patterns are assumed to be uniform at different heights when reconstructing moving objects. Therefore, the error caused by a perspective projection system becomes pronounced in phase-measuring profilometry, especially for some high precision metrology applications such as measuring the surfaces of the semiconductor components at micrometer level. In this work, we investigate the perspective effect on phase-measuring profilometry when reconstructing the surfaces of moving objects. Using a polynomial to approximate the phase distribution under a perspective projection system, which we call a polynomial phase-measuring profilometry (P-PMP) model, we are able to generalize the phase-measuring profilometry model discussed in our previous work and solve the phase reconstruction problem effectively. Furthermore, we can characterize how the frequency of the projected pattern changes according to the height variations and how the phase of the projected pattern distributes in the measuring space. We also propose a polynomial phase-shift algorithm (P-PSA) to correct the phase-shift error due to perspective effect during phase reconstruction. Simulation experiments show that the proposed method can improve the reconstruction quality both visually and numerically.

  20. Recent developments for high-precision mass measurements of the heaviest elements at SHIPTRAP

    NASA Astrophysics Data System (ADS)

    Minaya Ramirez, E.; Ackermann, D.; Blaum, K.; Block, M.; Droese, C.; Düllmann, Ch. E.; Eibach, M.; Eliseev, S.; Haettner, E.; Herfurth, F.; Heßberger, F. P.; Hofmann, S.; Marx, G.; Nesterenko, D.; Novikov, Yu. N.; Plaß, W. R.; Rodríguez, D.; Scheidenberger, C.; Schweikhard, L.; Thirolf, P. G.; Weber, C.

    2013-12-01

    Atomic nuclei far from stability continue to challenge our understanding. For example, theoretical models have predicted an “island of stability” in the region of the superheavy elements due to the closure of spherical proton and neutron shells. Depending on the model, these are expected at Z = 114, 120 or even 126 and N = 172 or 184. Valuable information on the road to the island of stability is derived from high-precision mass measurements, which give direct access to binding energies of short-lived trans-uranium nuclei. Recently, direct mass measurements at SHIPTRAP have been extended to nobelium and lawrencium isotopes around the deformed shell gap N = 152. In order to further extend mass measurements to the region of superheavy elements, new technical developments are required to increase the performance of our setup. The sensitivity will increase through the implementation of a new detection method, where observation of one single ion is sufficient. Together with the use of a more efficient gas stopping cell, this will us allow to significantly enhance the overall efficiency of SHIPTRAP.

  1. High-precision measurement of satellite range and velocity using the EISCAT radar

    NASA Astrophysics Data System (ADS)

    Markkanen, J.; Nygrén, T.; Markkanen, M.; Voiculescu, M.; Aikio, A.

    2013-05-01

    This paper is a continuation of an earlier work by Nygrén et al. (2012), where the velocity of a hard target was determined from a set of echo pulses reflected by the target flying through the radar beam. Here the method is extended to include the determination of range at a high accuracy. The method is as follows. First, the flight time of the pulse from the transmitter to the target is determined at an accuracy essentially better than the accuracy given by the sampling interval. This method makes use of the fact that the receiver filtering creates slopes at the phase flips of the phase modulated echo pulse. A precise flight time is found by investigating the echo amplitude within this slope. A value of velocity is calculated from each echo pulse as explained in the earlier paper. Next, the ranges together with velocities from a single beam pass are combined to a measurement vector for a linear inversion problem. The solution of the inversion problem gives the time-dependent range and velocity from the time interval of satellite flight through the radar beam. The method is demonstrated using the EISCAT (European Incoherent Scatter) UHF radar and radio pulses reflected by a satellite. The achieved standard deviations of range are about 5-50 cm and those of velocity are about 3-25 mm s-1.

  2. Precision multidimensional assay for high-throughput microRNA drug discovery.

    PubMed

    Haefliger, Benjamin; Prochazka, Laura; Angelici, Bartolomeo; Benenson, Yaakov

    2016-01-01

    Development of drug discovery assays that combine high content with throughput is challenging. Information-processing gene networks can address this challenge by integrating multiple potential targets of drug candidates' activities into a small number of informative readouts, reporting simultaneously on specific and non-specific effects. Here we show a family of networks implementing this concept in a cell-based drug discovery assay for miRNA drug targets. The networks comprise multiple modules reporting on specific effects towards an intended miRNA target, together with non-specific effects on gene expression, off-target miRNAs and RNA interference pathway. We validate the assays using known perturbations of on- and off-target miRNAs, and evaluate an ∼700 compound library in an automated screen with a follow-up on specific and non-specific hits. We further customize and validate assays for additional drug targets and non-specific inputs. Our study offers a novel framework for precision drug discovery assays applicable to diverse target families.

  3. Research on the polishing technology of high-precision aspherical cylindrical lens

    NASA Astrophysics Data System (ADS)

    Fu, Xiu-hua; Wang, Zhe; Jia, Zong-he; Dong, Huan; Liu, Dan; Zhang, Chuan-xin

    2014-08-01

    Aspherical cylindrical lens compared with the cylindrical lens, they improved image quality and optical properties, simplified the system architecture. They applied in many fields, such as high power laser system, fax machines and typographical scan imaging system, as well as bar code scanning, lighting and other aspects of holography. Aspherical cylindrical lens are centrosymmetric. It is difficult to process. Parallel with the side line and bus bar line is difficult to ensure. Machining accuracy is low. It is usually about 15 μm, that not sufficient to meet the needs of modern highprecision laser systems. These have become a major problem restricting its development. Combining traditional and modern polishing techniques, a new technique for polishing aspherical cylindrical lens is proposed-- longitudinal feedback compensation technology. With dimensions of 15 × 5 × 5 mm quartz aspherical cylindrical lens as an example, the surface profilometer results of detection of the workpiece usually, modify the shape of the polishing surface of the mold, to control the size of the area of the polishing, the surface of the workpiece to achieve the effect of the type of compensation. After repeated testing and feedback compensation, gradually improve the accuracy of the workpiece surface type. The results show that this technique can effectively improve the precision aspherical cylindrical lens. After detection the workpiece surface accuracy is 0.8μm, the surface finish is Class II. It has the actual production of a certain application value.

  4. High Precision Ranging and Range-Rate Measurements over Free-Space-Laser Communication Link

    NASA Technical Reports Server (NTRS)

    Yang, Guangning; Lu, Wei; Krainak, Michael; Sun, Xiaoli

    2016-01-01

    We present a high-precision ranging and range-rate measurement system via an optical-ranging or combined ranging-communication link. A complete bench-top optical communication system was built. It included a ground terminal and a space terminal. Ranging and range rate tests were conducted in two configurations. In the communication configuration with 622 data rate, we achieved a two-way range-rate error of 2 microns/s, or a modified Allan deviation of 9 x 10 (exp -15) with 10 second averaging time. Ranging and range-rate as a function of Bit Error Rate of the communication link is reported. They are not sensitive to the link error rate. In the single-frequency amplitude modulation mode, we report a two-way range rate error of 0.8 microns/s, or a modified Allan deviation of 2.6 x 10 (exp -15) with 10 second averaging time. We identified the major noise sources in the current system as the transmitter modulation injected noise and receiver electronics generated noise. A new improved system will be constructed to further improve the system performance for both operating modes.

  5. High-Precision Determination of the Pion-Nucleon σ Term from Roy-Steiner Equations.

    PubMed

    Hoferichter, Martin; Ruiz de Elvira, Jacobo; Kubis, Bastian; Meißner, Ulf-G

    2015-08-28

    We present a determination of the pion-nucleon (πN) σ term σ_{πN} based on the Cheng-Dashen low-energy theorem (LET), taking advantage of the recent high-precision data from pionic atoms to pin down the πN scattering lengths as well as of constraints from analyticity, unitarity, and crossing symmetry in the form of Roy-Steiner equations to perform the extrapolation to the Cheng-Dashen point in a reliable manner. With isospin-violating corrections included both in the scattering lengths and the LET, we obtain σ_{πN}=(59.1±1.9±3.0)  MeV=(59.1±3.5)  MeV, where the first error refers to uncertainties in the πN amplitude and the second to the LET. Consequences for the scalar nucleon couplings relevant for the direct detection of dark matter are discussed. PMID:26371645

  6. High-precision measurements of wetland sediment elevation. II The rod surface elevation table

    USGS Publications Warehouse

    Cahoon, D.R.; Lynch, J.C.; Perez, B.C.; Segura, B.; Holland, R.D.; Stelly, C.; Stephenson, G.; Hensel, P.

    2002-01-01

    A new high-precision device for measuring sediment elevation in emergent and shallow water wetland systems is described. The rod surface-elevation table (RSET) is a balanced, lightweight mechanical leveling device that attaches to both shallow ( 1 m in order to be stable. The pipe is driven to refusal but typically to a depth shallower than the rod bench mark because of greater surface resistance of the pipe. Thus, the RSET makes it possible to partition change in sediment elevation over shallower (e.g., the root zone) and deeper depths of the sediment profile than is possible with the SET. The confidence intervals for the height of an individual pin measured by two different operators with the RSET under laboratory conditions were A? 1.0 and A? 1.5 mm. Under field conditions, confidence intervals for the measured height of an individual pin ranged from A? 1.3 mm in a mangrove forest up to A? 4.3 mm in a salt marsh.

  7. High precision quantification of human plasma proteins using the automated SISCAPA Immuno-MS workflow.

    PubMed

    Razavi, Morteza; Leigh Anderson, N; Pope, Matthew E; Yip, Richard; Pearson, Terry W

    2016-09-25

    Efficient robotic workflows for trypsin digestion of human plasma and subsequent antibody-mediated peptide enrichment (the SISCAPA method) were developed with the goal of improving assay precision and throughput for multiplexed protein biomarker quantification. First, an 'addition only' tryptic digestion protocol was simplified from classical methods, eliminating the need for sample cleanup, while improving reproducibility, scalability and cost. Second, methods were developed to allow multiplexed enrichment and quantification of peptide surrogates of protein biomarkers representing a very broad range of concentrations and widely different molecular masses in human plasma. The total workflow coefficients of variation (including the 3 sequential steps of digestion, SISCAPA peptide enrichment and mass spectrometric analysis) for 5 proteotypic peptides measured in 6 replicates of each of 6 different samples repeated over 6 days averaged 3.4% within-run and 4.3% across all runs. An experiment to identify sources of variation in the workflow demonstrated that MRM measurement and tryptic digestion steps each had average CVs of ∼2.7%. Because of the high purity of the peptide analytes enriched by antibody capture, the liquid chromatography step is minimized and in some cases eliminated altogether, enabling throughput levels consistent with requirements of large biomarker and clinical studies.

  8. Influence of material removal programming on ion beam figuring of high-precision optical surfaces

    NASA Astrophysics Data System (ADS)

    Liao, Wenlin; Dai, Yifan; Xie, Xuhui

    2014-09-01

    Ion beam figuring (IBF) provides a nanometer/subnanometer precision fabrication technology for optical components, where the surface materials on highlands are gradually removed by the physical sputtering effect. In this deterministic method, the figuring process is usually divided into several iterations and the sum of the removed material in each iteration is expected to approach the ideally removed material as nearly as possible. However, we find that the material removal programming in each iteration would influence the surface error convergence of the figuring process. The influence of material removal programming on the surface error evolution is investigated through the comparative study of the contour removal method (CRM) and the geometric proportion removal method (PRM). The research results indicate that the PRM can maintenance the smoothness of the surface topography during the whole figuring process, which would benefit the stable operation of the machine tool and avoid the production of mid-to-high spatial frequency surface errors. Additionally, the CRM only has the corrective effect on the area above the contour line in each iteration, which would result in the nonuniform convergence of the surface errors in various areas. All these advantages distinguish PRM as an appropriate material removal method for ultraprecision optical surfaces.

  9. High-precision diode-laser-based temperature measurement for air refractive index compensation

    SciTech Connect

    Hieta, Tuomas; Merimaa, Mikko; Vainio, Markku; Seppae, Jeremias; Lassila, Antti

    2011-11-01

    We present a laser-based system to measure the refractive index of air over a long path length. In optical distance measurements, it is essential to know the refractive index of air with high accuracy. Commonly, the refractive index of air is calculated from the properties of the ambient air using either Ciddor or Edlen equations, where the dominant uncertainty component is in most cases the air temperature. The method developed in this work utilizes direct absorption spectroscopy of oxygen to measure the average temperature of air and of water vapor to measure relative humidity. The method allows measurement of temperature and humidity over the same beam path as in optical distance measurement, providing spatially well-matching data. Indoor and outdoor measurements demonstrate the effectiveness of the method. In particular, we demonstrate an effective compensation of the refractive index of air in an interferometric length measurement at a time-variant and spatially nonhomogeneous temperature over a long time period. Further, we were able to demonstrate 7 mK RMS noise over a 67 m path length using a 120 s sample time. To our knowledge, this is the best temperature precision reported for a spectroscopic temperature measurement.

  10. Precision multidimensional assay for high-throughput microRNA drug discovery

    PubMed Central

    Haefliger, Benjamin; Prochazka, Laura; Angelici, Bartolomeo; Benenson, Yaakov

    2016-01-01

    Development of drug discovery assays that combine high content with throughput is challenging. Information-processing gene networks can address this challenge by integrating multiple potential targets of drug candidates' activities into a small number of informative readouts, reporting simultaneously on specific and non-specific effects. Here we show a family of networks implementing this concept in a cell-based drug discovery assay for miRNA drug targets. The networks comprise multiple modules reporting on specific effects towards an intended miRNA target, together with non-specific effects on gene expression, off-target miRNAs and RNA interference pathway. We validate the assays using known perturbations of on- and off-target miRNAs, and evaluate an ∼700 compound library in an automated screen with a follow-up on specific and non-specific hits. We further customize and validate assays for additional drug targets and non-specific inputs. Our study offers a novel framework for precision drug discovery assays applicable to diverse target families. PMID:26880188

  11. High-precision isotopic characterization of USGS reference materials by TIMS and MC-ICP-MS

    NASA Astrophysics Data System (ADS)

    Weis, Dominique; Kieffer, Bruno; Maerschalk, Claude; Barling, Jane; de Jong, Jeroen; Williams, Gwen A.; Hanano, Diane; Pretorius, Wilma; Mattielli, Nadine; Scoates, James S.; Goolaerts, Arnaud; Friedman, Richard M.; Mahoney, J. Brian

    2006-08-01

    The Pacific Centre for Isotopic and Geochemical Research (PCIGR) at the University of British Columbia has undertaken a systematic analysis of the isotopic (Sr, Nd, and Pb) compositions and concentrations of a broad compositional range of U.S. Geological Survey (USGS) reference materials, including basalt (BCR-1, 2; BHVO-1, 2), andesite (AGV-1, 2), rhyolite (RGM-1, 2), syenite (STM-1, 2), granodiorite (GSP-2), and granite (G-2, 3). USGS rock reference materials are geochemically well characterized, but there is neither a systematic methodology nor a database for radiogenic isotopic compositions, even for the widely used BCR-1. This investigation represents the first comprehensive, systematic analysis of the isotopic composition and concentration of USGS reference materials and provides an important database for the isotopic community. In addition, the range of equipment at the PCIGR, including a Nu Instruments Plasma MC-ICP-MS, a Thermo Finnigan Triton TIMS, and a Thermo Finnigan Element2 HR-ICP-MS, permits an assessment and comparison of the precision and accuracy of isotopic analyses determined by both the TIMS and MC-ICP-MS methods (e.g., Nd isotopic compositions). For each of the reference materials, 5 to 10 complete replicate analyses provide coherent isotopic results, all with external precision below 30 ppm (2 SD) for Sr and Nd isotopic compositions (27 and 24 ppm for TIMS and MC-ICP-MS, respectively). Our results also show that the first- and second-generation USGS reference materials have homogeneous Sr and Nd isotopic compositions. Nd isotopic compositions by MC-ICP-MS and TIMS agree to within 15 ppm for all reference materials. Interlaboratory MC-ICP-MS comparisons show excellent agreement for Pb isotopic compositions; however, the reproducibility is not as good as for Sr and Nd. A careful, sequential leaching experiment of three first- and second-generation reference materials (BCR, BHVO, AGV) indicates that the heterogeneity in Pb isotopic compositions

  12. High-Precision Shape Control of In-Space Deployable Large Membrane/Thin-Shell Reflectors

    NASA Technical Reports Server (NTRS)

    Watkins, Ronald; Goebel, Dan; Hofer, Richard

    2010-01-01

    This innovation has been developed to improve the resolutions of future spacebased active and passive microwave antennas for earth-science remote sensing missions by maintaining surface figure precisions of large membrane/thin-shell reflectors during orbiting. The intention is for these sensing instruments to be deployable at orbit altitudes one or two orders of magnitude higher than Low Earth Orbit (LEO), but still being able to acquire measurements at spatial resolution and sensitivity similar to those of LEO. Because active and passive microwave remote sensors are able to penetrate through clouds to acquire vertical profile measurements of geophysical parameters, it is desirable to elevate them to the higher orbits to obtain orbital geometries that offer large spatial coverage and more frequent observations. This capability is essential for monitoring and for detailed understanding of the life cycles of natural hazards, such as hurricanes, tropical storms, flash floods, and tsunamis. Major components of this high-precision antenna-surface-control system include a membrane/thin shell reflector, a metrology sensor, a controller, actuators, and corresponding power amplifier and signal conditioning electronics (see figure). Actuators are attached to the back of the reflector to produce contraction/ expansion forces to adjust the shape of the thin-material reflector. The wavefront-sensing metrology system continuously measures the surface figure of the reflector, converts the surface figure to digital data and feeds the data to the controller. The controller determines the control parameters and generates commands to the actuator system. The flexible, piezoelectric polymer actuators are thus activated, providing the control forces needed to correct any distortions that exist in the reflector surface. Piezoelectric polymer actuators are very thin and flexible. They can be implemented on the back of the membrane/thin-shell reflector without introducing significant

  13. Telluric Line Effect on High Precision Radial Velocity Survey of K and M Dwarfs

    NASA Astrophysics Data System (ADS)

    Sithajan, Sirinrat; Ge, Jian; Wang, Ji

    2016-01-01

    better than the broad optical spectrograph in any cases with the same residual levels. These indicate the broad optical spectrograph can potentially be an optimal spectrograph for high precision RV surveys for low mass planets.

  14. High resolution and high precision on line isotopic analysis of Holocene and glacial ice performed in the field

    NASA Astrophysics Data System (ADS)

    Gkinis, V.; Popp, T. J.; Johnsen, S. J.; Blunier, T.; Bigler, M.; Stowasser, C.; Schüpbach, S.; Leuenberger, D.

    2010-12-01

    Ice core records as obtained from polar ice caps provide a wealth of paleoclimatic information. One of the main features of ice cores is their potential for high temporal resolution. The isotopic signature of the ice, expressed through the relative abundances of the two heavy isotopologues H218O and HD16O, is a widely used proxy for the reconstruction of past temperature and accumulation. One step further the combined information obtained from these two isotopologues, commonly referred to as the deuterium excess, can be utilized to infer additional information about the source of the precipitated moisture. Until very recently isotopic analysis of polar ice was performed with isotope Ratio Mass Spectrometry (IRMS) in a discrete fashion resulting in a high workload related to the preparation of samples. Most important though the available temporal resolution of the ice core was in many cases not fully exploited. In order to overcome these limitations we have developed a system that interfaces a commercially available IR laser cavity ring-down spectrometer tailored for water isotope analysis to a stream of liquid water as extracted from a continuously melted ice rod. The system offers the possibility for simultaneous δ18O and δD analysis with a sample requirement of approximately 0.1 ml/min. The system has been deployed in the field during the NEEM ice core drilling project on 2009 and 2010. In this study we present actual on line measurements of Holocene and glacial ice. We also discuss how parameters as the melt rate, acquisition rate and integration time affect the obtained precision and resolution and we describe data analysis techniques that can improve these last two parameters. By applying spectral methods we are able to quantify the smoothing effects imposed by diffusion of the sample in the sample transfer lines and the optical cavity of the instrument. We demonstrate that with an acquisition rate of 0.2 Hz we are able to obtain a precision of 0.5‰ and 0

  15. Trends in experimental high-energy physics

    SciTech Connect

    Sanford, T.W.L.

    1982-06-01

    Data from a scan of papers in Physical Review Letters and Physical Review are used to demonstrate that American high-energy physicists show a pattern of accelerator and instrumentation usage characteristic of that expected from the logistic-substitution model of Marchetti and of Fischer and Pry.

  16. A comprehensive filtering scheme for high-resolution estimation of the water balance components from high-precision lysimeters

    NASA Astrophysics Data System (ADS)

    Hannes, M.; Wollschlager, U.; Schrader, F.; Durner, W.; Gebler, S.; Putz, T.; Fank, J.; von Unold, G.; Vogel, H.-J.

    2015-08-01

    Large weighing lysimeters are currently the most precise method to directly measure all components of the terrestrial water balance in parallel via the built-in weighing system. As lysimeters are exposed to several external forces such as management practices or wind influencing the weighing data, the calculated fluxes of precipitation and evapotranspiration can be altered considerably without having applied appropriate corrections to the raw data. Therefore, adequate filtering schemes for obtaining most accurate estimates of the water balance components are required. In this study, we use data from the TERENO (TERrestrial ENvironmental Observatories) SoilCan research site in Bad Lauchstadt to develop a comprehensive filtering procedure for high-precision lysimeter data, which is designed to deal with various kinds of possible errors starting from the elimination of large disturbances in the raw data resulting e.g., from management practices all the way to the reduction of noise caused e.g., by moderate wind. Furthermore, we analyze the influence of averaging times and thresholds required by some of the filtering steps on the calculated water balance and investigate the ability of two adaptive filtering methods (the adaptive window and adaptive threshold filter (AWAT filter; Peters et al., 2014), and a new synchro filter applicable to the data from a set of several lysimeters) to further reduce the filtering error. Finally, we take advantage of the data sets of all 18 lysimeters running in parallel at the Bad Lauchstadt site to evaluate the performance and accuracy of the proposed filtering scheme. For the tested time interval of 2 months, we show that the estimation of the water balance with high temporal resolution and good accuracy is possible. The filtering code can be downloaded from the journal website as Supplement to this publication.

  17. High-precision Non-Contact Measurement of Creep of Ultra-High Temperature Materials for Aerospace

    NASA Technical Reports Server (NTRS)

    Rogers, Jan R.; Hyers, Robert

    2008-01-01

    For high-temperature applications (greater than 2,000 C) such as solid rocket motors, hypersonic aircraft, nuclear electric/thermal propulsion for spacecraft, and more efficient jet engines, creep becomes one of the most important design factors to be considered. Conventional creep-testing methods, where the specimen and test apparatus are in contact with each other, are limited to temperatures approximately 1,700 C. Development of alloys for higher-temperature applications is limited by the availability of testing methods at temperatures above 2000 C. Development of alloys for applications requiring a long service life at temperatures as low as 1500 C, such as the next generation of jet turbine superalloys, is limited by the difficulty of accelerated testing at temperatures above 1700 C. For these reasons, a new, non-contact creep-measurement technique is needed for higher temperature applications. A new non-contact method for creep measurements of ultra-high-temperature metals and ceramics has been developed and validated. Using the electrostatic levitation (ESL) facility at NASA Marshall Space Flight Center, a spherical sample is rotated quickly enough to cause creep deformation due to centrifugal acceleration. Very accurate measurement of the deformed shape through digital image analysis allows the stress exponent n to be determined very precisely from a single test, rather than from numerous conventional tests. Validation tests on single-crystal niobium spheres showed excellent agreement with conventional tests at 1985 C; however the non-contact method provides much greater precision while using only about 40 milligrams of material. This method is being applied to materials including metals and ceramics for non-eroding throats in solid rockets and next-generation superalloys for turbine engines. Recent advances in the method and the current state of these new measurements will be presented.

  18. Using optical trap to measure the refractive index of a single animal virus in culture fluid with high precision

    PubMed Central

    Pang, Yuanjie; Song, Hanna; Cheng, Wei

    2016-01-01

    The refractive index (RI) is a fundamental parameter of materials that can be used to distinguish and sort materials of different nature. Although the RI of a virus is required for many optics-based biosensing applications, RIs of animal viruses have never been measured. Here we have developed a technique that can measure the RI of individual viruses in aqueous media with high precision. This technique is based on optical trapping of single virions and works by relating the size and RI of a single virus to the stiffness of an optical trap. We have derived an analytic expression to quantitatively describe the optical trapping of these particles. We have validated this equation using nanoparticles of known RI, and measured the RI of individual human immunodeficiency viruses type-1, which yielded a value of 1.42 at 830 nm with less than 2% coefficient of variation. This value is much lower than the RI typically assumed for viruses, but very close to that of 2.0 M sucrose solution in water. To the best of our knowledge, this is the first report on the experimental measurement of the RI for a single animal virus in aqueous media. This technique does not require prior knowledge on the diameter of the nanoparticles, and can be applied to other viruses or nanoparticles for accurate measurement of RI that is critical for the label-free detection of these particles in various settings. PMID:27231613

  19. Spatial dependent diffusion of cosmic rays and the excess of primary electrons derived from high precision measurements by AMS-02

    NASA Astrophysics Data System (ADS)

    Jin, Chao; Guo, Yi-Qing; Hu, Hong-Bo

    2016-01-01

    The precise spectra of Cosmic Ray (CR) electrons and positrons have been published by the measurement of AMS-02. It is reasonable to regard the difference between the electron and positron spectra (ΔΦ = Φe- -Φe+) as being dominated by primary electrons. The resulting electron spectrum shows no sign of spectral softening above 20 GeV, which is in contrast with the prediction of the standard model of CR propagation. In this work, we generalize the analytic one-dimensional two-halo model of diffusion to a three-dimensional realistic calculation by implementing spatial variant diffusion coefficients in the DRAGON package. As a result, we can reproduce the spectral hardening of protons observed by several experiments, and predict an excess of high energy primary electrons which agrees with the measurement reasonably well. Unlike the break spectrum obtained for protons, the model calculation predicts a smooth electron excess and thus slightly over-predicts the flux from tens of GeV to 100 GeV. To understand this issue, further experimental and theoretical studies are necessary. Supported by Natural Sciences Foundation of China (11135010)

  20. Precision control of high temperature furnaces using an auxiliary power supply and charged particle current flow

    DOEpatents

    Pollock, G.G.

    1997-01-28

    Two power supplies are combined to control a furnace. A main power supply heats the furnace in the traditional manner, while the power from the auxiliary supply is introduced as a current flow through charged particles existing due to ionized gas or thermionic emission. The main power supply provides the bulk heating power and the auxiliary supply provides a precise and fast power source such that the precision of the total power delivered to the furnace is improved. 5 figs.