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Sample records for plate measuring machine

  1. The StarScan Plate Measuring Machine: Overview and Calibrations

    DTIC Science & Technology

    2008-05-28

    negligible, and we measure here the accuracy of the x, y-table coordinates of StarScan. In the following we refer to these sets of measures as m1c and m2c ...BETWEEN TWO SETS OF DATA, DCP IS CALIBRATION PLATE, M1C AND M2C ARE THE SETS 1 AND 2 OF MEASURES OF CENTRAL DOTS, AND 000 TO 270 INDICATE THE...ORIENTATION OF A MEASURE. SEE TEXT FOR MORE DETAILS. Result number Data set 1 Data set 2 Model rms x (μm) rms y (μm) 1 DCP m1c 000 DCP m2c 000 linear 0.31 0.20

  2. Shuttle plate braiding machine

    NASA Technical Reports Server (NTRS)

    Huey, Jr., Cecil O. (Inventor)

    1994-01-01

    A method and apparatus for moving yarn in a selected pattern to form a braided article. The apparatus includes a segmented grid of stationary support elements and a plurality of shuttles configured to carry yarn. The shuttles are supported for movement on the grid assembly and each shuttle includes a retractable plunger for engaging a reciprocating shuttle plate that moves below the grid assembly. Such engagement at selected times causes the shuttles to move about the grid assembly in a selected pattern to form a braided article of a particular geometry.

  3. Electrochemical Machining of Metal Plates

    SciTech Connect

    Cooper, J F; Evans, M C

    2005-03-04

    Electrochemical machining (ECM) with concentrated sodium chlorate electrolyte was used to rapidly cut a circular groove (13 cm diameter, 0.2 cm wide) through a 0.15 cm thick sheet of steel--thus opening a 5-inch porthole in as little as 10 minutes. The most favorable operating conditions were: T = 22 C; chlorate concentration 600 g NaClO{sub 3}/liter-solution; electric power of 100 A at 10 V; and flow of 0.5 l/s at a pressure drop of 10 kPa (1.5 psi). The porthole may be removed entirely by electrochemical means, or the electrochemical dissolution may continue until only thin membrane remains that is subsequently cut with a utility knife. An array of thermocouples was used to track temperature in the flowing solution and in the trough being machined; the maximum increase in temperature in the trough was 5 C over that of the flowing electrolyte which increased in temperature by 19 C because of power dissipation. ECM is shown feasible for rapid perforation of plates of ferrous and non-ferrous metals using portable equipment and commercial batteries. The technique can be extended to cut perforations of arbitrary shape through non-planar surfaces using a deformable ring cathode. Analysis of the power requirements for electrolyte flow and ECM indicate a total system weight of less than 45 kg (100 lb) using a commercial NiMH battery. The technique is recommended for reduction to practice and demonstration on full scale as an engineering prototype.

  4. KEY COMPARISON: Final report on CCL-K6: Calibration of coordinate measuring machine two-dimensional artifacts (ball & bore plates)

    NASA Astrophysics Data System (ADS)

    Viliesid, Miguel

    2009-01-01

    The Mutual Recognition Arrangement of the CIPM indicates that a metrological equivalence of national measurement standards and calibration certificates issued by national metrology institutes (NMIs) should be established by a set of key comparisons chosen and organized by the Consultative Committees of the Comité Internationale des Poids et Mesures on key techniques. The CCL (Comité Consultative de Longueur), identified several key comparisons in the field of dimensional metrology. In particular, it decided that a coordinate measuring machine (CMM) two-dimensional (2-D) artifact should be carried out. CENAM (Centro Nacional de Metrología) was designated as pilot laboratory and NMIs of signatories of the Metre Convention were invited to participate. The comparison is aimed to support the Calibration and Measurement Capabilities (CMCs) claims of NMIs for CMM 2-D standards calibration. Twelve NMIs from four Regional Metrology Organizations finished the comparison and one withdrew. The final participants were as follows: NMIA (CSIRO), Australia INMS-NRC, Canada NIM, China CMI, Czech Republic BNM-LNE, France PTB, Germany NMIJ (NRLM), Japan NMi, Netherlands VNIIM, Russia NPL, United Kingdom NIST, USA (1) CENAM, Mexico (1). A Draft B report was circulated among the participants and, after review and approval by all of the participants, it became the final report. It comprises all the information about the comparison: the measurement results, the choice of a Key Comparison Reference Value, the estimation of its uncertainty, the performance of each participant with respect to this value and the Birge ratio for each measurand of the two artifacts. It was decided afterwards at CCL that the exercise be classed as a supplementary comparison but the reference of CCL-K6 was kept. In an Appendix the equivalences of all measurands of each laboratory with respect to the reference value are reported for both artifacts, as well as the pairwise equivalences between laboratories for

  5. Armor Plate Surface Roughness Measurements

    DTIC Science & Technology

    2005-04-01

    Armor Plate Surface Roughness Measurements by Brian Stanton, William Coburn, and Thomas J. Pizzillo ARL-TR-3498 April 2005... Armor Plate Surface Roughness Measurements Brian Stanton, William Coburn and Thomas J. Pizzillo Sensors and Electron Devices Directorate...October 2004 5a. CONTRACT NUMBER 5b. GRANT NUMBER 4. TITLE AND SUBTITLE Armor Plate Surface Roughness Measurements 5c. PROGRAM ELEMENT NUMBER

  6. Incremental ECAP of thick continuous plates - machine and initial trials

    NASA Astrophysics Data System (ADS)

    Rosochowski, A.; Olejnik, L.

    2014-08-01

    Incremental ECAP (I-ECAP) can be used for SPD of continuous bars, plates and sheets. This paper describes design, construction and preliminary trials of a prototype machine capable of processing thick continuous plates. To increase productivity, a two-turn I-ECAP is used, which is equivalent to route C in conventional one-turn ECAP. The machine has a reciprocating punch inclined at 45°, a clamp holding the plate in the die during deformation and a feeder incrementally feeding the plate when it is not deformed; all these devices are driven by hydraulic actuators controlled by a PLC. The machine is capable of deforming materials at room temperature as well as elevated temperatures. The die is heated with electric heaters. The machine has also an integrated cooling system and a lubrication system. The material used for the initial trials was Al 1050 plate (10×50×1000) conversion coated with calcium aluminate and lubricated with dry soap. The process was carried out at room temperature using 1.6 mm feeding stroke and a low cycle frequency of approximately 0.2 Hz. The UFG structure after the first pass of the process revealed by STEM confirms process feasibility.

  7. 3. This machine in building #7 plated the hooks used ...

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

    3. This machine in building #7 plated the hooks used on the cross chains in tire chains, by the 'pean' or mechanical process. This process was replaced when coated wire was introduced. - American Chain & Cable Company, East Princess Street (400 Block), York, York County, PA

  8. Specimen coordinate automated measuring machine/fiducial automated measuring machine

    SciTech Connect

    Hedglen, Robert E.; Jacket, Howard S.; Schwartz, Allan I.

    1991-01-01

    The Specimen coordinate Automated Measuring Machine (SCAMM) and the Fiducial Automated Measuring Machine (FAMM) is a computer controlled metrology system capable of measuring length, width, and thickness, and of locating fiducial marks. SCAMM and FAMM have many similarities in their designs, and they can be converted from one to the other without taking them out of the hot cell. Both have means for: supporting a plurality of samples and a standard; controlling the movement of the samples in the +/- X and Y directions; determining the coordinates of the sample; compensating for temperature effects; and verifying the accuracy of the measurements and repeating as necessary. SCAMM and FAMM are designed to be used in hot cells.

  9. Coordinate measuring machine test standard apparatus and method

    DOEpatents

    Bieg, Lothar F.

    1994-08-30

    A coordinate measuring machine test standard apparatus and method which iudes a rotary spindle having an upper phase plate and an axis of rotation, a kinematic ball mount attached to the phase plate concentric with the axis of rotation of the phase plate, a groove mounted at the circumference of the phase plate, and an arm assembly which rests in the groove. The arm assembly has a small sphere at one end and a large sphere at the other end. The small sphere may be a coordinate measuring machine probe tip and may have variable diameters. The large sphere is secured in the kinematic ball mount and the arm is held in the groove. The kinematic ball mount includes at least three mounting spheres and the groove is an angular locating groove including at least two locking spheres. The arm may have a hollow inner core and an outer layer. The rotary spindle may be a ratio reducer. The device is used to evaluate the measuring performance of a coordinate measuring machine for periodic recertification, including 2 and 3 dimensional accuracy, squareness, straightness, and angular accuracy.

  10. Coordinate measuring machine test standard apparatus and method

    DOEpatents

    Bieg, L.F.

    1994-08-30

    A coordinate measuring machine test standard apparatus and method are disclosed which includes a rotary spindle having an upper phase plate and an axis of rotation, a kinematic ball mount attached to the phase plate concentric with the axis of rotation of the phase plate, a groove mounted at the circumference of the phase plate, and an arm assembly which rests in the groove. The arm assembly has a small sphere at one end and a large sphere at the other end. The small sphere may be a coordinate measuring machine probe tip and may have variable diameters. The large sphere is secured in the kinematic ball mount and the arm is held in the groove. The kinematic ball mount includes at least three mounting spheres and the groove is an angular locating groove including at least two locking spheres. The arm may have a hollow inner core and an outer layer. The rotary spindle may be a ratio reducer. The device is used to evaluate the measuring performance of a coordinate measuring machine for periodic recertification, including 2 and 3 dimensional accuracy, squareness, straightness, and angular accuracy. 5 figs.

  11. Machine learning for precise quantum measurement.

    PubMed

    Hentschel, Alexander; Sanders, Barry C

    2010-02-12

    Adaptive feedback schemes are promising for quantum-enhanced measurements yet are complicated to design. Machine learning can autonomously generate algorithms in a classical setting. Here we adapt machine learning for quantum information and use our framework to generate autonomous adaptive feedback schemes for quantum measurement. In particular, our approach replaces guesswork in quantum measurement by a logical, fully automatic, programable routine. We show that our method yields schemes that outperform the best known adaptive scheme for interferometric phase estimation.

  12. Heat transfer measurements for Stirling machine cylinders

    NASA Technical Reports Server (NTRS)

    Kornhauser, Alan A.; Kafka, B. C.; Finkbeiner, D. L.; Cantelmi, F. C.

    1994-01-01

    The primary purpose of this study was to measure the effects of inflow-produced heat turbulence on heat transfer in Stirling machine cylinders. A secondary purpose was to provide new experimental information on heat transfer in gas springs without inflow. The apparatus for the experiment consisted of a varying-volume piston-cylinder space connected to a fixed volume space by an orifice. The orifice size could be varied to adjust the level of inflow-produced turbulence, or the orifice plate could be removed completely so as to merge the two spaces into a single gas spring space. Speed, cycle mean pressure, overall volume ratio, and varying volume space clearance ratio could also be adjusted. Volume, pressure in both spaces, and local heat flux at two locations were measured. The pressure and volume measurements were used to calculate area averaged heat flux, heat transfer hysteresis loss, and other heat transfer-related effects. Experiments in the one space arrangement extended the range of previous gas spring tests to lower volume ratio and higher nondimensional speed. The tests corroborated previous results and showed that analytic models for heat transfer and loss based on volume ratio approaching 1 were valid for volume ratios ranging from 1 to 2, a range covering most gas springs in Stirling machines. Data from experiments in the two space arrangement were first analyzed based on lumping the two spaces together and examining total loss and averaged heat transfer as a function of overall nondimensional parameter. Heat transfer and loss were found to be significantly increased by inflow-produced turbulence. These increases could be modeled by appropriate adjustment of empirical coefficients in an existing semi-analytic model. An attempt was made to use an inverse, parameter optimization procedure to find the heat transfer in each of the two spaces. This procedure was successful in retrieving this information from simulated pressure-volume data with artificially

  13. Self-Calibrating Surface Measuring Machine

    NASA Astrophysics Data System (ADS)

    Greenleaf, Allen H.

    1983-04-01

    A new kind of surface-measuring machine has been developed under government contract at Itek Optical Systems, a Division of Itek Corporation, to assist in the fabrication of large, highly aspheric optical elements. The machine uses four steerable distance-measuring interferometers at the corners of a tetrahedron to measure the positions of a retroreflective target placed at various locations against the surface being measured. Using four interferometers gives redundant information so that, from a set of measurement data, the dimensions of the machine as well as the coordinates of the measurement points can be determined. The machine is, therefore, self-calibrating and does not require a structure made to high accuracy. A wood-structured prototype of this machine was made whose key components are a simple form of air bearing steering mirror, a wide-angle cat's eye retroreflector used as the movable target, and tracking sensors and servos to provide automatic tracking of the cat's eye by the four laser beams. The data are taken and analyzed by computer. The output is given in terms of error relative to an equation of the desired surface. In tests of this machine, measurements of a 0.7 m diameter mirror blank have been made with an accuracy on the order of 0.2µm rms.

  14. Programmable phase plate for tool modification in laser machining applications

    DOEpatents

    Thompson Jr., Charles A.; Kartz, Michael W.; Brase, James M.; Pennington, Deanna; Perry, Michael D.

    2004-04-06

    A system for laser machining includes a laser source for propagating a laser beam toward a target location, and a spatial light modulator having individual controllable elements capable of modifying a phase profile of the laser beam to produce a corresponding irradiance pattern on the target location. The system also includes a controller operably connected to the spatial light modulator for controlling the individual controllable elements. By controlling the individual controllable elements, the phase profile of the laser beam may be modified into a desired phase profile so as to produce a corresponding desired irradiance pattern on the target location capable of performing a machining operation on the target location.

  15. Drag Measurements of Porous Plate Acoustic Liners

    NASA Technical Reports Server (NTRS)

    Wolter, John D.

    2005-01-01

    This paper presents the results of direct drag measurements on a variety of porous plate acoustic liners. The existing literature describes numerous studies of drag on porous walls with injection or suction, but relatively few of drag on porous plates with neither injection nor suction. Furthermore, the porosity of the porous plate in existing studies is much lower than typically used in acoustic liners. In the present work, the acoustic liners consisted of a perforated face sheet covering a bulk acoustic absorber material. Factors that were varied in the experiment were hole diameter, hole pattern, face sheet thickness, bulk material type, and size of the gap (if any) between the face sheet and the absorber material.

  16. Laser measuring system for large machine tools

    NASA Astrophysics Data System (ADS)

    Wessel, L. E.; Brazys, D.

    1982-08-01

    With development of the Laser Interferometer, it was envisioned that older existing machine tools could be up-graded by retrofitting them with laser Interferometer Measuring Systems. The Laser Interferometer provides the machine tool industry with a high accuracy length standard. The accuracy of the Interferometer is determined by the laser wave length which is known within 0.5 parts per million. This degree of accuracy is more than adequate for most machine tool measuring, calibration and inspection requirements. In conclusion, the Laser Measuring System presently available is not recommended for general implementation at this time. Results of this work indicate that the equipment and installation cost are very high and pay back would be very slow. Also, the reliability of the electronic components is in need of improvement. The system requires frequent realignment and maintenance due to it's lack of toleration to "Shop Floor' conditions.

  17. Copper Conductivity Model Development and Validation Using Flyer Plate Experiments on the Z-machine

    NASA Astrophysics Data System (ADS)

    Riford, L.; Lemke, R. W.; Cochrane, K.

    2015-11-01

    Magnetically accelerated flyer plate experiments done on Sandia's Z-machine provide insight into a multitude of materials problems at high energies and densities including conductivity model development and validation. In an experiment with ten Cu flyer plates of thicknesses 500-1000 μm, VISAR measurements exhibit a characteristic jump in the velocity correlated with magnetic field burn-through and the expansion of melted material at the free surface. The experiment is modeled using Sandia's shock and multiphysics MHD code ALEGRA. Simulated free surface velocities are within 1% of the measured data early in time, but divergence occurs at the feature, where the simulation indicates a slower burn through time. The cause was found to be in the Cu conductivity model's compressed regime. The model was improved by lowering the conductivity in the region 12.5-16 g/cc and 350-16000 K with a novel parameter based optimization method using the velocity feature as a figure of merit. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U. S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  18. Fiber optic strain measurement for machine monitoring

    NASA Astrophysics Data System (ADS)

    Hoffmann, L.; Mueller, M. S.; Koch, A. W.

    2007-06-01

    Monitoring machines during operation is an important issue in measurement engineering. The usual approach to monitoring specific machine components is using strain gauges. Strain gauges, however, may sometimes not be used if conditions are harsh or installation space is limited. Fiber optic sensors seem to be an alternative here, but dynamic health monitoring has been dificult so far. The focus of this field study is to measure vibration characteristics of machine parts during operation using fiber optic sensors with the objective of early damage detection. If that was possible, downtime and maintenance costs could be minimized. Therefore a field test for dynamic fiber optic strain measurement on a roller bearing was carried out. The test setup consisted of the bearing built into a gear test stand and equipped with an array of fiber Bragg grating sensors. Fifteen fiber sensors were interrogated with a sample rate of 1 kHz and the vibration pattern was extracted. The radial load distribution was measured with high spatial resolution and a high degree of compliance with simulation data was found. The findings suggest that fiber optic health monitoring for machine components is feasible and reasonable. Especially with the help of distributed sensing on various components extensive health monitoring on complex technical systems is possible.

  19. The Automatic Measuring Machines and Ground-Based Astrometry

    NASA Astrophysics Data System (ADS)

    Sergeeva, T. P.

    The introduction of the automatic measuring machines into the astronomical investigations a little more then a quarter of the century ago has increased essentially the range and the scale of projects which the astronomers could capable to realize since then. During that time, there have been dozens photographic sky surveys, which have covered all of the sky more then once. Due to high accuracy and speed of automatic measuring machines the photographic astrometry has obtained the opportunity to create the high precision catalogs such as CpC2. Investigations of the structure and kinematics of the stellar components of our Galaxy has been revolutionized in the last decade by the advent of automated plate measuring machines. But in an age of rapidly evolving electronic detectors and space-based catalogs, expected soon, one could think that the twilight hours of astronomical photography have become. On opposite of that point of view such astronomers as D.Monet (U.S.N.O.), L.G.Taff (STScI), M.K.Tsvetkov (IA BAS) and some other have contended the several ways of the photographic astronomy evolution. One of them sounds as: "...special efforts must be taken to extract useful information from the photographic archives before the plates degrade and the technology required to measure them disappears". Another is the minimization of the systematic errors of ground-based star catalogs by employment of certain reduction technology and a dense enough and precise space-based star reference catalogs. In addition to that the using of the higher resolution and quantum efficiency emulsions such as Tech Pan and some of the new methods of processing of the digitized information hold great promise for future deep (B<25) surveys (Bland-Hawthorn et al. 1993, AJ, 106, 2154). Thus not only the hard working of all existing automatic measuring machines is apparently needed but the designing, development and employment of a new generation of portable, mobile scanners is very necessary. The

  20. Reflectometer distance measurement between parallel conductive plates

    NASA Technical Reports Server (NTRS)

    Hearn, Chase P.; Neece, Robert T.

    1995-01-01

    This report presents an analytic and experimental investigation of the measurement problem in which a reflectometer is used to determine the distance to a target that is a highly conductive surface parallel to the reflectometer antenna ground plane. These parallel surfaces constitute a waveguide (WG) which can contribute parasitic perturbations that seriously degrade the accuracy of the measurements. Two distinct parallel-plate-waveguide (PPWG) phenomena are described, and their effects on both frequency and time-domain reflectometers are considered. The time-domain processing approach was found to be superior to a representative frequency-domain phase-measurement approach because of less susceptibility to perturbations produced by edge reflections and immunity to phase capture. Experimental results are presented which show that a simple radiating system modification can suppress parallel-plate (PP) propagation. The addition of a thin layer of lossy mu-metal 'magnetic absorber' to the antenna ground plane allowed a measurement accuracy of 0.025 cm (0.01 in.) when a vector network analyzer (VNA) is used as a time-domain reflectometer.

  1. Measurement of Pinion Type Cutter Using Coordinate Measuring Machine

    NASA Astrophysics Data System (ADS)

    Liu, Zongxian; Tamura, Hisashi; Kawasaki, Kazumasa; Mitome, Ken-Ichi

    A method for measuring a pinion type cutter using a coordinate measuring machine is proposed. In this method, the cutting edge profile of the cutter is indirectly measured as the intersecting curve between the flank of tool and the cutting face. Left and right side flanks of the cutter are considered to be the tooth surfaces of two different involute helical gears. The coordinates of many points on the tooth surface and the face are measured using a coordinate measuring machine. The tooth surface and the face are estimated from the measured data by the method of least squares. The cutting edge profile is calculated from the estimated tooth surface and the face. The cutting edge is moved helically and it forms the tooth surface of the actual imaginary gear. A pressure angle of this gear can be calculated. Pressure angle error of the pinion type cutter is that of the imaginary gear.

  2. Measure Transformer Semantics for Bayesian Machine Learning

    NASA Astrophysics Data System (ADS)

    Borgström, Johannes; Gordon, Andrew D.; Greenberg, Michael; Margetson, James; van Gael, Jurgen

    The Bayesian approach to machine learning amounts to inferring posterior distributions of random variables from a probabilistic model of how the variables are related (that is, a prior distribution) and a set of observations of variables. There is a trend in machine learning towards expressing Bayesian models as probabilistic programs. As a foundation for this kind of programming, we propose a core functional calculus with primitives for sampling prior distributions and observing variables. We define combinators for measure transformers, based on theorems in measure theory, and use these to give a rigorous semantics to our core calculus. The original features of our semantics include its support for discrete, continuous, and hybrid measures, and, in particular, for observations of zero-probability events. We compile our core language to a small imperative language that has a straightforward semantics via factor graphs, data structures that enable many efficient inference algorithms. We use an existing inference engine for efficient approximate inference of posterior marginal distributions, treating thousands of observations per second for large instances of realistic models.

  3. A New Guarded Hot Plate Designed for Thermal-Conductivity Measurements at High Temperature

    NASA Astrophysics Data System (ADS)

    Scoarnec, V.; Hameury, J.; Hay, B.

    2015-03-01

    The Laboratoire National de Métrologie et d'Essais has developed a new guarded hot-plate apparatus operating from to in the thermal-conductivity range from to . This facility has been specifically designed for measuring medium thermal-conductivity materials at high temperature on square specimens (100 mm side), which are easier to machine than circular ones. The hot plate and cold plates are similar with a metering section independent from the guard ring. The specimens are laterally isolated by an air gap of 4 mm width and can be instrumented by temperature sensors in order to reduce effects of thermal contact resistances between the specimens and the heating plates. Measurements have been performed on certified reference materials and on "calibrated" materials. Relative deviations between thermal conductivities measured and reference values are less than 5 % in the operating range.

  4. Dynamometer for measuring machining forces in two perpendicular directions

    NASA Technical Reports Server (NTRS)

    Sutherland, I. A.

    1974-01-01

    Published report discusses development of two-component force dynamometer which is used for dynamic measurement of machining forces in cutting and thrust directions. Resulting data suggest that faster metal-cutting machines may be developed that have reduced vibrations.

  5. Compensation strategy for machining optical freeform surfaces by the combined on- and off-machine measurement.

    PubMed

    Zhang, Xiaodong; Zeng, Zhen; Liu, Xianlei; Fang, Fengzhou

    2015-09-21

    Freeform surface is promising to be the next generation optics, however it needs high form accuracy for excellent performance. The closed-loop of fabrication-measurement-compensation is necessary for the improvement of the form accuracy. It is difficult to do an off-machine measurement during the freeform machining because the remounting inaccuracy can result in significant form deviations. On the other side, on-machine measurement may hides the systematic errors of the machine because the measuring device is placed in situ on the machine. This study proposes a new compensation strategy based on the combination of on-machine and off-machine measurement. The freeform surface is measured in off-machine mode with nanometric accuracy, and the on-machine probe achieves accurate relative position between the workpiece and machine after remounting. The compensation cutting path is generated according to the calculated relative position and shape errors to avoid employing extra manual adjustment or highly accurate reference-feature fixture. Experimental results verified the effectiveness of the proposed method.

  6. Noncontact infrared temperature measurement using machine vision

    NASA Astrophysics Data System (ADS)

    Zhong, Fei; Shi, Tielin; He, Tao; Zhong, Yuning

    2006-11-01

    Temperature monitoring is a common requirement; the thermocouples can accurately control the temperature of rotating and moving heated object, without touching it. Uncoated metal heaters are difficult for infrared sensors to measure reliably, the reflected infrared signals can change after a heated object surface is clean, the smog is rareness after the clean heated object has been burnt, when the surface is dirty and smeary, the smog is so dense that the measurement result would be influenced. In order to measuring the metal heater accurately, the measurement noise can be reduced by the machine vision. The Self-Organizing Maps (SOM) is an efficient tool for image processing. It projects input space on prototypes of a low-dimensional regular grid. In this paper a new image process technique has been validated against U-matrix method based on Euclidean distances between input vectors and neurons weights combined with the distribution of the fixed lattices in the network. SOM, as an unsupervised neural networks, is applied to pattern recognition and image processing. By analyzing and processing of the noise signals of the image, the characteristic parameters which represent operating state of the heated object are extracted to construct characteristic vector and used to train SOM. The trained results can be used to modify the sensor testing value. A new image processing scheme based on the use of the organization property of Kohonen maps are presented in this paper, the image processing result can be correct the non-contact infrared temperature measurement.

  7. Highly accurate articulated coordinate measuring machine

    DOEpatents

    Bieg, Lothar F.; Jokiel, Jr., Bernhard; Ensz, Mark T.; Watson, Robert D.

    2003-12-30

    Disclosed is a highly accurate articulated coordinate measuring machine, comprising a revolute joint, comprising a circular encoder wheel, having an axis of rotation; a plurality of marks disposed around at least a portion of the circumference of the encoder wheel; bearing means for supporting the encoder wheel, while permitting free rotation of the encoder wheel about the wheel's axis of rotation; and a sensor, rigidly attached to the bearing means, for detecting the motion of at least some of the marks as the encoder wheel rotates; a probe arm, having a proximal end rigidly attached to the encoder wheel, and having a distal end with a probe tip attached thereto; and coordinate processing means, operatively connected to the sensor, for converting the output of the sensor into a set of cylindrical coordinates representing the position of the probe tip relative to a reference cylindrical coordinate system.

  8. Machining of micro-through-holes on glass plate by femtosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Yasui, Motohiro; Aoki, Hikoharu; Miyamoto, Isamu

    2003-02-01

    Lime-glass and silica-glass plates with thickness of 100 μm were drilled with a ultra-short pulse laser(780nm, 150fs pulses at 1kHz). The surface of the glass plate at front side and rear side were observed by SEM, and the transmitted laser power though the glass plate was measured for both of glass. The appearance of the drilled hole of lime-glass was compared with that of silica-glass. The drilling characteristics of lime-glass and silica-glass plates with thickness of 100 μm by femto-second laser pulse were studied. On rear side, the crack occurred before drilling through the plate. The crack on the rear side occurred in lime-glass at smaller shot number than in silica-glass. The transmitted laser power ratio was decreased with increasing laser intensity. Interesting phenomenon that the lower glass plate began to be drilled before the upper glass plate was drilled through, when two glass plates with air gap of 12 μm were drilled.

  9. Finite Element Analysis of Warpage in Laminated Aluminium Alloy Plates for Machining of Primary Aeronautic Parts

    SciTech Connect

    Reis, A. C.; Moreira Filho, L. A.; Menezes, M. A.

    2007-04-07

    The aim of this paper consists in presenting a method of simulating the warpage in 7xxx series aluminium alloy plates. To perform this simulation finite element software MSC.Patran and MSC.Marc were used. Another result of this analysis will be the influence on material residual stresses induced on the raw material during the rolling process upon the warpage of primary aeronautic parts, fabricated through machining (milling) at Embraer. The method used to determinate the aluminium plate residual stress was Layer Removal Test. The numerical algorithm Modified Flavenot Method was used to convert layer removal and beam deflection in stress level. With such information about the level and profile of residual stresses become possible, during the step that anticipate the manufacturing to incorporate these values in the finite-element approach for modelling warpage parts. Based on that warpage parameter surely the products are manufactured with low relative vulnerability propitiating competitiveness and price.

  10. Retardation Measurements of Infrared PVA Wave plate

    NASA Astrophysics Data System (ADS)

    Sun, Y.; Z, H.; W, D.; D, Y.; Z, Z.; S, J.

    The wave plate made of Polyvinyl Alcohol PVA plastic film has several advantages such as its lower cost and insensitivity to temperature and incidence angle so it has been used in the Solar Multi-Channel Telescope SMCT in China But the important parameter retardations of PVA wave plates in the near infrared wavelength have never been provided In this paper a convenient and high precise instrument to get the retardations of discrete wavelengths or a continuous function of wavelength in near infrared is developed In this method the retardations of wave plates have been determined through calculating the maximum and minimum of light intensity The instrument error has been shown Additionally we can get the continuous direction of wavelength retardations in the ultraviolet visible or infrared spectral in another way

  11. Development of a shear measurement sensor for measuring forces at human-machine interfaces.

    PubMed

    Cho, Young Kuen; Kim, Seong Guk; Kim, Donghyun; Kim, Hyung Joo; Ryu, Jeicheong; Lim, Dohyung; Ko, Chang-Yong; Kim, Han Sung

    2014-12-01

    Measuring shear force is crucial for investigating the pathology and treatment of pressure ulcers. In this study, we introduced a bi-axial shear transducer based on strain gauges as a new shear sensor. The sensor consisted of aluminum and polyvinyl chloride plates placed between quadrangular aluminum plates. On the middle plate, two strain gauges were placed orthogonal to one another. The shear sensor (54 mm × 54 mm × 4.1 mm), which was validated by using standard weights, displayed high accuracy and precision (measurement range, -50 to 50 N; sensitivity, 0.3N; linear relationship, R(2)=0.9625; crosstalk error, 0.635% ± 0.031%; equipment variation, 4.183). The shear force on the interface between the human body and a stand-up wheelchair was measured during sitting or standing movements, using two mats (44.8 cm × 44.8 cm per mat) that consisted of 24 shear sensors. Shear forces on the sacrum and ischium were almost five times higher (15.5 N at last posture) than those on other sites (3.5 N on average) during experiments periods. In conclusion, the proposed shear sensor may be reliable and useful for measuring the shear force on human-machine interfaces.

  12. Method for measuring the contour of a machined part

    DOEpatents

    Bieg, Lothar F.

    1995-05-30

    A method for measuring the contour of a machined part with a contour gage apparatus, having a probe assembly including a probe tip for providing a measure of linear displacement of the tip on the surface of the part. The contour gage apparatus may be moved into and out of position for measuring the part while the part is still carried on the machining apparatus. Relative positions between the part and the probe tip may be changed, and a scanning operation is performed on the machined part by sweeping the part with the probe tip, whereby data points representing linear positions of the probe tip at prescribed rotation intervals in the position changes between the part and the probe tip are recorded. The method further allows real-time adjustment of the apparatus machining the part, including real-time adjustment of the machining apparatus in response to wear of the tool that occurs during machining.

  13. Method for measuring the contour of a machined part

    DOEpatents

    Bieg, L.F.

    1995-05-30

    A method is disclosed for measuring the contour of a machined part with a contour gage apparatus, having a probe assembly including a probe tip for providing a measure of linear displacement of the tip on the surface of the part. The contour gage apparatus may be moved into and out of position for measuring the part while the part is still carried on the machining apparatus. Relative positions between the part and the probe tip may be changed, and a scanning operation is performed on the machined part by sweeping the part with the probe tip, whereby data points representing linear positions of the probe tip at prescribed rotation intervals in the position changes between the part and the probe tip are recorded. The method further allows real-time adjustment of the apparatus machining the part, including real-time adjustment of the machining apparatus in response to wear of the tool that occurs during machining. 5 figs.

  14. Are they animals or machines? Measuring dehumanization.

    PubMed

    Martínez, Rocío; Rodríguez-Bailón, Rosa; Moya, Miguel

    2012-11-01

    The present research deals with two forms of dehumanization: 1) denying uniquely human attributes to others (seeing them as animals); 2) denying human nature to others (seeing them as machines or automata). Studies 1 and 2 explored these two forms of dehumanization, analyzing whether people associated their ingroup more with human-related words (vs. animal- vs. machine-related words) than two different outgroups. A paper and pencil procedure was used to find out which words were associated with the surnames of the ingroup (Spaniards) or the outgroup (Germans, Gypsies). Results showed that participants were more ready to link ingroup than outgroup surnames to human words. They also linked more Gypsy surnames to animal-related words and German surnames with machine-related words. Studies 3 and 4 used the Implicit Association Test to analyze the same ideas and replicated the results of Studies 1 and 2.

  15. Absolute viscosity measured using instrumented parallel plate system

    NASA Technical Reports Server (NTRS)

    Broyles, H. H.

    1967-01-01

    An automatic system measures the true average shear viscosity of liquids and viscoelastic materials, using the parallel plate method and automatically displays the results on a graphic record. This eliminates apparatus setup and extensive calculations.

  16. Vision-based on-machine measurement for CNC machine tool

    NASA Astrophysics Data System (ADS)

    Xia, Ruixue; Han, Jiang; Lu, Rongsheng; Xia, Lian

    2015-02-01

    A vision-based on-machine measurement system (OMM) was developed to improve manufacturing effectiveness. It was based on a visual probe to enable the CNC machine tool itself to act as a coordinate measuring machine (CMM) to inspect a workpiece. The proposed OMM system was composed of a visual probe and two software modules: computer-aided inspection planning (CAIP) module and measurement data processing (MDP) module. The auto-focus function of the visual probe was realized by using astigmatic method. The CAIP module was developed based on a CAD development platform with Open CASCADE as its kernel. The MDP module includes some algorithms for determination of inspection parameters, for example, the chamfered hole was measured through focus variation. The entire system was consequently verified on a CNC milling machine.

  17. Grating pitch measurements with the molecular measuring machine

    NASA Astrophysics Data System (ADS)

    Kramar, John; Jun, Jau-Shi J.; Penzes, William B.; Scire, Fredric; Teague, E. Clayton; Villarrubia, John S.

    1999-11-01

    At the National Institute of Standards and Technology, we are building a metrology instrument called the Molecular Measuring Machine (M3) with the goal of performing nanometer- accuracy two-dimensional feature placement measurements over a 50 mm by 50 mm area. The instrument uses a scanning tunneling microscope to probe the surface and an interferometer system to measure the lateral probe movement, both having sub-nanometer resolution. The continuous vertical measurement range is 5 micrometer, and up to 2 mm can be covered by stitching overlapping ranges. The instrument includes temperature control with millikelvin stability, an ultra-high vacuum environment with a base pressure below 10-5 Pa, and seismic and acoustic vibration isolation. Pitch measurements were performed on gratings made by holographic exposure of photoresist and on gratings made by laser-focused atomic deposition of Cr. The line pitch for these gratings ranged from 200 nm to 400 nm with an estimated standard uncertainty of the average pitch of 25 X 10-6. This fractional uncertainty is derived from an analysis of the sources of uncertainty for a 1 mm point-to- point measurement, including the effects of alignment, Abbe offset, motion cross-coupling, and temperature variations. These grating pitch measurements are uniquely accomplished on M3 because of the combination of probe resolution and long-range interferometer-controlled stage. This instrument could uniquely address certain dimensional metrology needs in the data storage industry.

  18. Automatic ball bar for a coordinate measuring machine

    DOEpatents

    Jostlein, H.

    1997-07-15

    An automatic ball bar for a coordinate measuring machine determines the accuracy of a coordinate measuring machine having at least one servo drive. The apparatus comprises a first and second gauge ball connected by a telescoping rigid member. The rigid member includes a switch such that inward radial movement of the second gauge ball relative to the first gauge ball causes activation of the switch. The first gauge ball is secured in a first magnetic socket assembly in order to maintain the first gauge ball at a fixed location with respect to the coordinate measuring machine. A second magnetic socket assembly secures the second gauge ball to the arm or probe holder of the coordinate measuring machine. The second gauge ball is then directed by the coordinate measuring machine to move radially inward from a point just beyond the length of the ball bar until the switch is activated. Upon switch activation, the position of the coordinate measuring machine is determined and compared to known ball bar length such that the accuracy of the coordinate measuring machine can be determined. 5 figs.

  19. Automatic ball bar for a coordinate measuring machine

    DOEpatents

    Jostlein, Hans

    1997-01-01

    An automatic ball bar for a coordinate measuring machine determines the accuracy of a coordinate measuring machine having at least one servo drive. The apparatus comprises a first and second gauge ball connected by a telescoping rigid member. The rigid member includes a switch such that inward radial movement of the second gauge ball relative to the first gauge ball causes activation of the switch. The first gauge ball is secured in a first magnetic socket assembly in order to maintain the first gauge ball at a fixed location with respect to the coordinate measuring machine. A second magnetic socket assembly secures the second gauge ball to the arm or probe holder of the coordinate measuring machine. The second gauge ball is then directed by the coordinate measuring machine to move radially inward from a point just beyond the length of the ball bar until the switch is activated. Upon switch activation, the position of the coordinate measuring machine is determined and compared to known ball bar length such that the accuracy of the coordinate measuring machine can be determined.

  20. A prediction method for separating and quantifying noise contributions from casings and other plate like components in complex machines

    NASA Astrophysics Data System (ADS)

    Nejade, A.

    2012-11-01

    In the context of noise source identification in machines, sound intensity, pressure or velocity distributions on a plane in space are commonly provided by intensity or holography maps. These maps, however, are not capable of separating the sources that are located on different planes, e.g. machines' radiating casings versus internal noise sources. The method discussed in this paper has been developed to analyze such situations. It consists of multiple partially coherent inputs-single output modeling to predict the radiations generated by machine casings or other plate like components. A parallel analysis with intensity will then enable to separate the casing or plate contribution from those of the internal sources. The application of this technique must, however, be accompanied by tools that allow to check its validity. Several of such tools are suggested. The method applications and validity checks have been discussed for a grinder wheel guard and a panel saw's blade casing.

  1. Machine Shop. Module 2: Measurement and Blueprint Reading. Instructor's Guide.

    ERIC Educational Resources Information Center

    Missouri Univ., Columbia. Instructional Materials Lab.

    This document consists of materials for a 12-unit course on the following topics: (1) introduction to precision measurement; (2) semiprecision linear measurement; (3) simple layout techniques; (4) measurement with vernier and dial calipers; (5) measuring with micrometers; (6) measurement and layout on a surface plate; (7) go/no-go inspection…

  2. Stress measurement in thick plates using nonlinear ultrasonics

    NASA Astrophysics Data System (ADS)

    Abbasi, Zeynab; Ozevin, Didem

    2015-03-01

    In this paper the interaction between nonlinear ultrasonic characteristics and stress state of complex loaded thick steel plates using fundamental theory of nonlinear ultrasonics is investigated in order to measure the stress state at a given cross section. The measurement concept is based on phased array placement of ultrasonic transmitter-receiver to scan three angles of a given cross section using Rayleigh waves. The change in the ultrasonic data in thick steel plates is influenced by normal and shear stresses; therefore, three measurements are needed to solve the equations simultaneously. Different thickness plates are studied in order to understand the interaction of Rayleigh wave penetration depth and shear stress. The purpose is that as the thickness becomes smaller, the shear stress becomes negligible at the angled measurement. For thicker cross section, shear stress becomes influential if the depth of penetration of Rayleigh wave is greater than the half of the thickness. The influences of plate thickness and ultrasonic frequency on the identification of stress tensor are numerically studied in 3D structural geometry and Murnaghan material model. The experimental component of this study includes uniaxial loading of the plate while measuring ultrasonic wave at three directions (perpendicular, parallel and angled to the loading direction). Instead of rotating transmitter-receiver pair for each test, a device capable of measuring the three angles is designed.

  3. Stress measurement in thick plates using nonlinear ultrasonics

    SciTech Connect

    Abbasi, Zeynab E-mail: dozevin@uic.edu; Ozevin, Didem E-mail: dozevin@uic.edu

    2015-03-31

    In this paper the interaction between nonlinear ultrasonic characteristics and stress state of complex loaded thick steel plates using fundamental theory of nonlinear ultrasonics is investigated in order to measure the stress state at a given cross section. The measurement concept is based on phased array placement of ultrasonic transmitter-receiver to scan three angles of a given cross section using Rayleigh waves. The change in the ultrasonic data in thick steel plates is influenced by normal and shear stresses; therefore, three measurements are needed to solve the equations simultaneously. Different thickness plates are studied in order to understand the interaction of Rayleigh wave penetration depth and shear stress. The purpose is that as the thickness becomes smaller, the shear stress becomes negligible at the angled measurement. For thicker cross section, shear stress becomes influential if the depth of penetration of Rayleigh wave is greater than the half of the thickness. The influences of plate thickness and ultrasonic frequency on the identification of stress tensor are numerically studied in 3D structural geometry and Murnaghan material model. The experimental component of this study includes uniaxial loading of the plate while measuring ultrasonic wave at three directions (perpendicular, parallel and angled to the loading direction). Instead of rotating transmitter-receiver pair for each test, a device capable of measuring the three angles is designed.

  4. ESPY measurements of submerged composite plate vibrations

    SciTech Connect

    Pechersky, M.J.

    1990-12-31

    An Electronic Speckle pattern interferometer (ESPI) was constructed which performs full-field surface displacement measurements. This measurement technique when combined with a single-point measurement known as laser vibrometry, can completely determine the vibrational characteristics of complex structures. This information can, in turn, be used for nondestructive testing as well as for modal analysis. One NDT&E technique is to vibrationally excite the object and evaluate the time averaged interferograms from the ESPI and the vibration spectra from the vibrometer. Anomalies in the interferograms can be related to subsurface defects such as defective weld joints, internal cracks, voids, etc. All of this can be accomplished in a noncontacting and nonintrusive manor. In many instances, a finite element analysis in concert with this approach can be useful in interpreting the results. Since ESPI is analogous to optical holography, other methods equivalent to real-time and double-pulse holography may also be easily applied. As in holography, EXSPI is sensitive to out-of-plane surface displacements. Other optical arrangements can be implemented with the same equipment to give in-plane displacements which would give results similar to Moire interferometry without the need to apply gratings to the object under test. The advantage of this method over holographic interferometry is that the feedback from the measurements is for all practical purposes instantaneous. This has important positive ramifications with regard to the ease of performing measurements, relaxed stability requirements, and reliability.

  5. ESPY measurements of submerged composite plate vibrations

    SciTech Connect

    Pechersky, M.J.

    1990-01-01

    An Electronic Speckle pattern interferometer (ESPI) was constructed which performs full-field surface displacement measurements. This measurement technique when combined with a single-point measurement known as laser vibrometry, can completely determine the vibrational characteristics of complex structures. This information can, in turn, be used for nondestructive testing as well as for modal analysis. One NDT E technique is to vibrationally excite the object and evaluate the time averaged interferograms from the ESPI and the vibration spectra from the vibrometer. Anomalies in the interferograms can be related to subsurface defects such as defective weld joints, internal cracks, voids, etc. All of this can be accomplished in a noncontacting and nonintrusive manor. In many instances, a finite element analysis in concert with this approach can be useful in interpreting the results. Since ESPI is analogous to optical holography, other methods equivalent to real-time and double-pulse holography may also be easily applied. As in holography, EXSPI is sensitive to out-of-plane surface displacements. Other optical arrangements can be implemented with the same equipment to give in-plane displacements which would give results similar to Moire interferometry without the need to apply gratings to the object under test. The advantage of this method over holographic interferometry is that the feedback from the measurements is for all practical purposes instantaneous. This has important positive ramifications with regard to the ease of performing measurements, relaxed stability requirements, and reliability.

  6. Electronic measurement of microchannel plate pulse height distributions

    SciTech Connect

    Gamboa, E. J.; Huntington, C. M.; Harding, E. C.; Drake, R. P.

    2010-10-15

    Microchannel plates are a central component of the x-ray framing cameras used as analog imagers in many plasma experiment diagnostic systems. The microchannel plate serves as an amplifying element, increasing the electronic signal from incident radiation by factors of 10{sup 3}-10{sup 5}, with a broad pulse-height distribution. Seeking to optimize the photon-to-electron conversion efficiency and noise distribution of x-ray cameras, we will characterize the pulse-height distribution of the electron output from a single microchannel plate. Replacing the framing camera's phosphor-coated fiber optic screen with a charge-collection plate and coupling to a low-noise multichannel analyzer, we quantified the distribution in the total charge generated per photon event. The electronically measured pulse height distribution is used to estimate the signal-to-noise ratio of radiographic images from framing cameras.

  7. Measuring surfactant concentration in plating solutions

    DOEpatents

    Bonivert, William D.; Farmer, Joseph C.; Hachman, John T.

    1989-01-01

    An arrangement for measuring the concentration of surfactants in a electrolyte containing metal ions includes applying a DC bias voltage and a modulated voltage to a counter electrode. The phase angle between the modulated voltage and the current response to the modulated voltage at a working electrode is correlated to the surfactant concentration.

  8. Tool wear of a single-crystal diamond tool in nano-groove machining of a quartz glass plate

    NASA Astrophysics Data System (ADS)

    Yoshino, Masahiko; Nakajima, Satoshi; Terano, Motoki

    2015-12-01

    Tool wear characteristics of a diamond tool in ductile mode machining are presented in this paper. Nano-groove machining of a quartz glass plate was conducted to examine the tool wear rate of a single-crystal diamond tool. Effects of lubrication on the tool wear rate were also evaluated. A numerical simulation technique was developed to evaluate the tool temperature and normal stress acting on the wear surface. From the simulation results it was found that the tool temperature does not increase during the machining experiment. It is also demonstrated that tool wear is attributed to the abrasive wear mechanism, but the effect of the adhesion wear mechanism is minor in nano-groove machining. It is found that the tool wear rate is reduced by using water or kerosene as a lubricant.

  9. The wear properties of CFR-PEEK-OPTIMA articulating against ceramic assessed on a multidirectional pin-on-plate machine.

    PubMed

    Scholes, S C; Unsworth, A

    2007-04-01

    In an attempt to prolong the lives of rubbing implantable devices, several 'new' materials have been examined to determine their suitability as joint couplings. Tests were performed on a multidirectional pin-on-plate machine to determine the wear of both pitch and PAN (polyacrylonitrile)-based carbon fibre reinforced-polyetheretherketone (CFR-PEEK-OPTIMA) pins articulating against both BioLox Delta and BioLox Forte plates (ceramic materials). Both reciprocation and rotational motion were applied to the samples. The tests were conducted using 24.5 per cent bovine serum as the lubricant (protein concentration 15 g/l). Although all four material combinations gave similar low wear with no statistically significant difference (p > 0.25), the lowest average total wear of these pin-on-plate tests was provided by CFR-PEEK-OPTIMA pitch pins versus BioLox Forte plates. This was much lower than the wear produced by conventional joint materials (metal-on-polyethylene) and metal-on-metal combinations when tested on the pin-on-plate machine. This therefore indicates optimism that these PEEK-OPTIMA-based material combinations may perform well in joint applications.

  10. Application of an On-machine Gage for Diameter Measurements

    NASA Technical Reports Server (NTRS)

    Harding, Kevin G.

    1993-01-01

    This paper describes the design analysis and application of a laser based gage made specifically for measuring parts on the machine tool to a high accuracy. The tri-beam gage uses three beams of light to measure the local curvature of the part in a manner similar to a V-block gage. The properties of this design include: calibration that is independent of the machine tool scales, non-contact damage free operation, low cost of the gage, and the ability to measure parts in motion.

  11. Control systems improvements in a precision coordinate measuring machine

    NASA Astrophysics Data System (ADS)

    Douglass, S. S.; Babelay, E. F., Jr.; Igou, R. E.; Woodard, L. M.; Green, W. L.

    1981-09-01

    A conventional, manually driven Moore No. 3 coordinate measuring machine at the Oak Ridge Y-12 Plant is being upgraded to provide a continuous-path numerical control capability and simultaneously serve as a vehicle for testing new machine slide-control concepts. Besides new lead screw drive motors, an NC machine control unit, and a closed-loop servo system, the machine has also been equipped with vibration isolation, air-bearing slideways, and laser interferometric position feedback. The present conventional slide servo system will be replaced with a digital servo system wherein various feedback and compensation techniques can be realized through the use of a high speed, dedicated digital processor. The improvements to data are described with emphasis on identification and compensation of the slide control systems.

  12. Rapid mapping of volumetric machine errors using distance measurements

    SciTech Connect

    Krulewich, D.A.

    1998-04-01

    This paper describes a relatively inexpensive, fast, and easy to execute approach to maping the volumetric errors of a machine tool, coordinate measuring machine, or robot. An error map is used to characterize a machine or to improve its accuracy by compensating for the systematic errors. The method consists of three steps: (1) models the relationship between volumetric error and the current state of the machine, (2) acquiring error data based on distance measurements throughout the work volume; and (3)fitting the error model using the nonlinear equation for the distance. The error model is formulated from the kinematic relationship among the six degrees of freedom of error an each moving axis. Expressing each parametric error as function of position each is combined to predict the error between the functional point and workpiece, also as a function of position. A series of distances between several fixed base locations and various functional points in the work volume is measured using a Laser Ball Bar (LBB). Each measured distance is a non-linear function dependent on the commanded location of the machine, the machine error, and the location of the base locations. Using the error model, the non-linear equation is solved producing a fit for the error model Also note that, given approximate distances between each pair of base locations, the exact base locations in the machine coordinate system determined during the non-linear filling procedure. Furthermore, with the use of 2048 more than three base locations, bias error in the measuring instrument can be removed The volumetric errors of three-axis commercial machining center have been mapped using this procedure. In this study, only errors associated with the nominal position of the machine were considered Other errors such as thermally induced and load induced errors were not considered although the mathematical model has the ability to account for these errors. Due to the proprietary nature of the projects we are

  13. Modification of Moore measuring machine/Leitz microscope

    NASA Technical Reports Server (NTRS)

    Greth, H. A.; Brubaker, L.

    1976-01-01

    Quality assurance mechanical inspection, anticipating the need for improved measuring techniques for the various laboratory programs, has perfected a modification of the Leitz microscope for the Moore measuring machine that has the capability of significantly reducing inspection time with increased reliability.

  14. Coordinate Measuring Machine Pit Artifact Inspection Procedure

    SciTech Connect

    Montano, Joshua D.

    2012-07-31

    The goal of this document is to outline a procedure for dimensional measurement of Los Alamos National Laboratory's CMM Pit Artifact. This procedure will be used by the Manufacturing Practice's Inspection Technology Subgroup of the Interagency Manufacturing Operations Group and Joint Operations Weapon Operations Group (IMOG/JOWOG 39) round robin participants. The intent is to assess the state of industry within the Nuclear Weapons Complex for measurements made on this type of part and find which current measurement strategies and techniques produce the best results.

  15. Measurement of steel plate perforation tests with digital image correlation.

    SciTech Connect

    Cordova, Theresa Elena; Reu, Phillip L.; Vangoethem, Douglas J.

    2009-03-01

    The results of a series of punch-through tests performed on steel plates are presented. The geometry consisted of circular plates with welded boundary condition penetrated by a conical shaped punch with either a radiused or flat cylindrical end. After initial failure, the conical portion of the punch was driven through the plate to exercise tearing mechanics. Tests were performed quasi-statically with a hydraulic actuator and dynamically using a high-capacity drop table. Deformation and strain were measured with a stereo DIC system. The quasi-static tests utilized a conventional direct-view DIC technique while the dynamic tests required development of an indirect-view technique using a mirror. Experimental details used to conduct the test series will be presented along with test results. Methods of assessing test-to-test repeatability will be discussed. DIC results will also be synchronized and compared with transducer data (displacement and strain).

  16. Advancements in the Interferometric Measurements of Real Time Finishing Birefringent Filter's Crystal Plates

    NASA Astrophysics Data System (ADS)

    Gan, Ma; Mgan, Ya; Kushtal Skomorovsky, Gi, Vi; Domyshev, Gn; Sadokhin, Vp

    2006-10-01

    The finishing of birefringent plates consists of two processes: polishing and evaluation of a surface, which have been performed separately till now. The purpose of this work is achieving of high accuracy of the evaluation and machining of the plane-parallel plates from birefringent crystals, in particular of crystal plates of birefringent filters during their finishing. The developed process combines evaluation and polishing in an interactive way. We have found modes of treatment, shape of polisher, have designed interferometer, with a mirror arranged in polisher. Visual checking of optical thickness comparatively with reference plate was carried out using the interference fringes of equal birefringence, and checking of an optical wedge - by interference rings of an equal inclination. The automated processing of TV camera interference fringes was impossible, because of gaps of interference fringes on polishing cells above the mirror. Therefore a special software was developed for processing of a complex fringe pattern interferogram. Software FastInterf uses furrier analysis technique which allows to process an interferogram with multiply gaps. Interferograms are registered by a high resolution TV camera (1280 ×1024). Automatic processing of a fringe interferogram using FastInterf software takes less then one second. The influence of gaps is excluded, and the flat field is taken into account. Software provides full 3D surface and wavefront maps. Aberration analysis of a wavefront gives information on thickness of a plate comparatively with a reference one, optical wedge of plate and azimuth of an inclination of wave front. Moreover, software provides a control of surface quality. The measuring device, features of the software are described and process of interferometric evaluation during polishing is illustrated.

  17. Torsion effect of swing frame on the measurement of horizontal two-plane balancing machine

    NASA Astrophysics Data System (ADS)

    Wang, Qiuxiao; Wang, Dequan; He, Bin; Jiang, Pan; Wu, Zhaofu; Fu, Xiaoyan

    2017-03-01

    In this paper, the vibration model of swing frame of two-plane balancing machine is established to calculate the vibration center position of swing frame first. The torsional stiffness formula of spring plate twisting around the vibration center is then deduced by using superposition principle. Finally, the dynamic balancing experiments prove the irrationality of A-B-C algorithm which ignores the torsion effect, and show that the torsional stiffness deduced by experiments is consistent with the torsional stiffness calculated by theory. The experimental datas show the influence of the torsion effect of swing frame on the separation ratio of sided balancing machines, which reveals the sources of measurement error and assesses the application scope of A-B-C algorithm.

  18. Measurement of seedling growth rate by machine vision

    NASA Astrophysics Data System (ADS)

    Howarth, M. Scott; Stanwood, Phillip C.

    1993-05-01

    Seed vigor and germination tests have traditionally been used to determine deterioration of seed samples. Vigor tests describe the seed potential to emerge and produce a mature crop under certain field conditions and one measure is seedling growth rate. A machine vision system was developed to measure root growth rate over the entire germination period. The machine vision measurement technique was compared to the manual growth rate technique. The vision system provided similar growth rate measurements as compared to the manual growth rate technique. The average error between the system and a manual measurement was -0.13 for the lettuce test and -0.07 for the sorghum test. This technique also provided an accurate representation of the growth rate as well as percent germination.

  19. Diamagnetic loop measurement in Korea Superconducting Tokamak Advanced Research machine.

    PubMed

    Bak, J G; Lee, S G; Kim, H S

    2011-06-01

    Diamagnetic loop (DL), which consists of two poloidal loops inside the vacuum vessel, is used to measure the diamagnetic flux during a plasma discharge in the Korea Superconducting Tokamak Advanced Research (KSTAR) machine. The vacuum fluxes in the DL signal can be compensated up to 0.1 mWb by using the coefficients, which are obtained from experimental investigations, in the vacuum flux measurements during vacuum shots under same operational conditions of magnetic coils for plasma experiment in the KSTAR machine. The maximum error in the diamagnetic flux measurement due to the errors of the coefficients was estimated as ∼0.22 mWb. From the diamagnetic flux measurements for the ohmically heated circular plasmas in the KSTAR machine, the stored energy agrees well with the estimated kinetic energy within the discrepancy of 25%. When the electron cyclotron heating, the neutral beam injection, and the ion cyclotron resonance heating are added to the ohmically heated limiter plasmas, the additional heating effects can be clearly observed from the increase of the stored energy evaluated in the DL measurement.

  20. Diamagnetic loop measurement in Korea Superconducting Tokamak Advanced Research machine

    SciTech Connect

    Bak, J. G.; Lee, S. G.; Kim, H. S.

    2011-06-15

    Diamagnetic loop (DL), which consists of two poloidal loops inside the vacuum vessel, is used to measure the diamagnetic flux during a plasma discharge in the Korea Superconducting Tokamak Advanced Research (KSTAR) machine. The vacuum fluxes in the DL signal can be compensated up to 0.1 mWb by using the coefficients, which are obtained from experimental investigations, in the vacuum flux measurements during vacuum shots under same operational conditions of magnetic coils for plasma experiment in the KSTAR machine. The maximum error in the diamagnetic flux measurement due to the errors of the coefficients was estimated as {approx}0.22 mWb. From the diamagnetic flux measurements for the ohmically heated circular plasmas in the KSTAR machine, the stored energy agrees well with the estimated kinetic energy within the discrepancy of 25%. When the electron cyclotron heating, the neutral beam injection, and the ion cyclotron resonance heating are added to the ohmically heated limiter plasmas, the additional heating effects can be clearly observed from the increase of the stored energy evaluated in the DL measurement.

  1. Accurate measurement method for tube's endpoints based on machine vision

    NASA Astrophysics Data System (ADS)

    Liu, Shaoli; Jin, Peng; Liu, Jianhua; Wang, Xiao; Sun, Peng

    2017-01-01

    Tubes are used widely in aerospace vehicles, and their accurate assembly can directly affect the assembling reliability and the quality of products. It is important to measure the processed tube's endpoints and then fix any geometric errors correspondingly. However, the traditional tube inspection method is time-consuming and complex operations. Therefore, a new measurement method for a tube's endpoints based on machine vision is proposed. First, reflected light on tube's surface can be removed by using photometric linearization. Then, based on the optimization model for the tube's endpoint measurements and the principle of stereo matching, the global coordinates and the relative distance of the tube's endpoint are obtained. To confirm the feasibility, 11 tubes are processed to remove the reflected light and then the endpoint's positions of tubes are measured. The experiment results show that the measurement repeatability accuracy is 0.167 mm, and the absolute accuracy is 0.328 mm. The measurement takes less than 1 min. The proposed method based on machine vision can measure the tube's endpoints without any surface treatment or any tools and can realize on line measurement.

  2. Vibration measurement of electrical machines using integrated fibre Bragg gratings

    NASA Astrophysics Data System (ADS)

    Fabian, M.; Borg Bartolo, J.; Ams, M.; Gerada, C.; Sun, T.; Grattan, K. T. V.

    2015-09-01

    In this paper a method to track the rotating force vector set up within the air-gap of radial flux rotating electrical machines using fibre Bragg gratings is reported. The proposed technique offers the potential for simultaneous rotor speed and position monitoring. This specific sensor design, together with other FBG-based multi-parameter measurements, is aimed to create an all-optical sensor solution for electrical machines, reducing the component count of existing systems and addressing noise issues traditionally associated with electrical sensors used. In this work, an optical fibre sensor system has been successfully integrated into an off-the-shelf four-pole 11kW induction motor.

  3. On machine capacitance dimensional and surface profile measurement system

    NASA Astrophysics Data System (ADS)

    Resnick, Ralph

    1993-02-01

    A program was awarded under the Air Force Machine Tool Sensor Improvements Program Research and Development Announcement to develop and demonstrate the use of a Capacitance Sensor System including Capacitive Non-Contact Analog Probe and a Capacitive Array Dimensional Measurement System to check the dimensions of complex shapes and contours on a machine tool or in an automated inspection cell. The manufacturing of complex shapes and contours and the subsequent verification of those manufactured shapes is fundamental and widespread throughout industry. The critical profile of a gear tooth; the overall shape of a graphite EDM electrode; the contour of a turbine blade in a jet engine; and countless other components in varied applications possess complex shapes that require detailed and complex inspection procedures. Current inspection methods for complex shapes and contours are expensive, time-consuming, and labor intensive.

  4. On Machine Capacitance Dimensional and Surface Profile Measurement System

    NASA Technical Reports Server (NTRS)

    Resnick, Ralph

    1993-01-01

    A program was awarded under the Air Force Machine Tool Sensor Improvements Program Research and Development Announcement to develop and demonstrate the use of a Capacitance Sensor System including Capacitive Non-Contact Analog Probe and a Capacitive Array Dimensional Measurement System to check the dimensions of complex shapes and contours on a machine tool or in an automated inspection cell. The manufacturing of complex shapes and contours and the subsequent verification of those manufactured shapes is fundamental and widespread throughout industry. The critical profile of a gear tooth; the overall shape of a graphite EDM electrode; the contour of a turbine blade in a jet engine; and countless other components in varied applications possess complex shapes that require detailed and complex inspection procedures. Current inspection methods for complex shapes and contours are expensive, time-consuming, and labor intensive.

  5. Statistical process control (SPC) for coordinate measurement machines

    SciTech Connect

    Escher, R.N.

    2000-01-04

    The application of process capability analysis, using designed experiments, and gage capability studies as they apply to coordinate measurement machine (CMM) uncertainty analysis and control will be demonstrated. The use of control standards in designed experiments, and the use of range charts and moving range charts to separate measurement error into it's discrete components will be discussed. The method used to monitor and analyze the components of repeatability and reproducibility will be presented with specific emphasis on how to use control charts to determine and monitor CMM performance and capability, and stay within your uncertainty assumptions.

  6. Measuring Transient Signals in Plate Boundary Faults Zones with Strainmeters

    NASA Astrophysics Data System (ADS)

    Hodgkinson, Kathleen; Mencin, Dave; Phillips, David; Henderson, Brent; Gottlieb, Mike; Gallaher, Warren; Johnson, Wade; Pyatt, Chad; Van Boskirk, Elizabeth; Fox, Otina; Mattioli, Glen; Meertens, Chuck

    2014-05-01

    One of the fundamental goals the U.S. National Science Foundation (NSF) funded Earthscope program was to provide a high-quality, continuous geodetic data set that would allow the scientific community to study the evolution of plate boundary zones. Of particular importance was enabling investigation of the role aseismic transient deformation plays in the release of accumulated stress. For example, to allow the comparison of the amount of strain released through Episodic Tremor and Slip (ETS) events to that released in subduction zone earthquakes or, provide the ability to geodetically illuminate the kinematics of fault creep in strike-slip fault zones. The ability to easily integrate these measurements with compatible geophysical data sets was also an essential objective. With goals such as these in mind NSF funded the Plate Boundary Observatory (PBO) to record the continuous deformation field across the western US Plate Boundary. PBO, built and operated by UNAVCO, now consists of over 1100 GPS stations, 76 co-located borehole strain and seismic sites, 6 long baseline strainmeters, Depending on the scientific questions being addressed sites may also have tiltmeter, meteorological, pore pressure and meteorological instrumentation. This presentation will focus on the transient deformation signals recorded by the PBO strainmeter network. PBO strainmeters, which excel in recording signals on the order of nanostrain over hours, have provided unprecedented temporal resolution of aseismic transients such as ETS events in the Cascadia subduction zone, creep signals along the central section of the San Andreas fault system and tsunami generated strain waves. UNAVCO is responsible not only for the ongoing operation of PBO but also the generation of data products associated with each instrument type. In this presentation we will highlight some of the transient signals these instruments have captured, outline the processing steps required to extract these signals data and

  7. Study on ultra-fine w-EDM with on-machine measurement-assisted

    SciTech Connect

    Chen Shuntong; Yang Hongye

    2011-01-17

    The purpose of this study was to develop the on-machine measurement techniques so as to precisely fabricate micro intricate part using ultra-fine w-EDM. The measurement-assisted approach which employs an automatic optical inspection (AOI) is incorporated to ultra-fine w-EDM process to on-machine detect the machining error for next re-machining. The AOI acquires the image through a high resolution CCD device from the contour of the workpiece after roughing in order to further process and recognize the image for determining the residual. This facilitates the on-machine error detection and compensation re-machining. The micro workpiece and electrode are not repositioned during machining. A fabrication for a micro probe of 30-{mu}m diameter is rapidly machined and verified successfully. Based on the proposed technique, on-machine measurement with AOI has been realized satisfactorily.

  8. 3-D measuring of engine camshaft based on machine vision

    NASA Astrophysics Data System (ADS)

    Qiu, Jianxin; Tan, Liang; Xu, Xiaodong

    2008-12-01

    The non-touch 3D measuring based on machine vision is introduced into camshaft precise measuring. Currently, because CCD 3-dimensional measuring can't meet requirements for camshaft's measuring precision, it's necessary to improve its measuring precision. In this paper, we put forward a method to improve the measuring method. A Multi-Character Match method based on the Polygonal Non-regular model is advanced with the theory of Corner Extraction and Corner Matching .This method has solved the problem of the matching difficulty and a low precision. In the measuring process, the use of the Coded marked Point method and Self-Character Match method can bring on this problem. The 3D measuring experiment on camshaft, which based on the Multi-Character Match method of the Polygonal Non-regular model, proves that the normal average measuring precision is increased to a new level less than 0.04mm in the point-clouds photo merge. This measuring method can effectively increase the 3D measuring precision of the binocular CCD.

  9. Measurement and modeling of pulsed microchannel plate operation (invited).

    PubMed

    Rochau, G A; Wu, M; Kruschwitz, C; Joseph, N; Moy, K; Bailey, J; Krane, M; Thomas, R; Nielsen, D; Tibbitts, A

    2008-10-01

    Microchannel plates (MCPs) are a standard detector for fast-framing x-ray imaging and spectroscopy of high-temperature plasmas. The MCP is coated with conductive striplines that carry short duration voltage pulses to control the timing and amplitude of the signal gain. This gain depends on the voltage to a large exponent so that small reflections or impedance losses along the striplines can have a significant impact on the position-dependent amplitude and pulse width of the gain. Understanding the pulsed gain response therefore requires careful measurements of the position- and time-dependent surface voltage coupled with detailed modeling of the resulting electron cascade. We present measurements and modeling of the time- and space-dependent gain response of MCP detectors designed for use at Sandia National Laboratories' Z facility. The pulsed gain response is understood through measurements using a high impedence probe to determine the voltage pulse propagating along the stripline surface. Coupling the surface voltage measurements with Monte Carlo calculations of the electron cascade in the MCP provides a prediction of the time- and position-dependent gain that agrees with measurements made on a subpicosecond UV laser source to within the 25% uncertainty in the simulations.

  10. Articulated Arm Coordinate Measuring Machine Calibration by Laser Tracker Multilateration

    PubMed Central

    Majarena, Ana C.; Brau, Agustín; Velázquez, Jesús

    2014-01-01

    A new procedure for the calibration of an articulated arm coordinate measuring machine (AACMM) is presented in this paper. First, a self-calibration algorithm of four laser trackers (LTs) is developed. The spatial localization of a retroreflector target, placed in different positions within the workspace, is determined by means of a geometric multilateration system constructed from the four LTs. Next, a nonlinear optimization algorithm for the identification procedure of the AACMM is explained. An objective function based on Euclidean distances and standard deviations is developed. This function is obtained from the captured nominal data (given by the LTs used as a gauge instrument) and the data obtained by the AACMM and compares the measured and calculated coordinates of the target to obtain the identified model parameters that minimize this difference. Finally, results show that the procedure presented, using the measurements of the LTs as a gauge instrument, is very effective by improving the AACMM precision. PMID:24688418

  11. Dynamical Mass Measurements of Contaminated Galaxy Clusters Using Machine Learning

    NASA Astrophysics Data System (ADS)

    Ntampaka, Michelle; Trac, Hy; Sutherland, Dougal; Fromenteau, Sebastien; Poczos, Barnabas; Schneider, Jeff

    2016-01-01

    Galaxy clusters are a rich source of information for examining fundamental astrophysical processes and cosmological parameters, however, employing clusters as cosmological probes requires accurate mass measurements derived from cluster observables. We study dynamical mass measurements of galaxy clusters contaminated by interlopers, and show that a modern machine learning (ML) algorithm can predict masses by better than a factor of two compared to a standard scaling relation approach. We create a mock catalog from Multidark's publicly-available N-body MDPL1 simulation where a simple cylindrical cut around the cluster center allows interlopers to contaminate the clusters. In the standard approach, we use a power law scaling relation to infer cluster mass from galaxy line of sight (LOS) velocity dispersion. The presence of interlopers in the catalog produces a wide, flat fractional mass error distribution, with width = 2.13. We employ the Support Distribution Machine (SDM) class of algorithms to learn from distributions of data to predict single values. Applied to distributions of galaxy observables such as LOS velocity and projected distance from the cluster center, SDM yields better than a factor-of-two improvement (width = 0.67). Remarkably, SDM applied to contaminated clusters is better able to recover masses than even a scaling relation approach applied to uncontaminated clusters. We show that the SDM method more accurately reproduces the cluster mass function, making it a valuable tool for employing cluster observations to evaluate cosmological models.

  12. Machine Learning for Discriminating Quantum Measurement Trajectories and Improving Readout.

    PubMed

    Magesan, Easwar; Gambetta, Jay M; Córcoles, A D; Chow, Jerry M

    2015-05-22

    Current methods for classifying measurement trajectories in superconducting qubit systems produce fidelities systematically lower than those predicted by experimental parameters. Here, we place current classification methods within the framework of machine learning (ML) algorithms and improve on them by investigating more sophisticated ML approaches. We find that nonlinear algorithms and clustering methods produce significantly higher assignment fidelities that help close the gap to the fidelity possible under ideal noise conditions. Clustering methods group trajectories into natural subsets within the data, which allows for the diagnosis of systematic errors. We find large clusters in the data associated with T1 processes and show these are the main source of discrepancy between our experimental and ideal fidelities. These error diagnosis techniques help provide a path forward to improve qubit measurements.

  13. Machine Learning for Discriminating Quantum Measurement Trajectories and Improving Readout

    NASA Astrophysics Data System (ADS)

    Magesan, Easwar; Gambetta, Jay M.; Córcoles, A. D.; Chow, Jerry M.

    2015-05-01

    Current methods for classifying measurement trajectories in superconducting qubit systems produce fidelities systematically lower than those predicted by experimental parameters. Here, we place current classification methods within the framework of machine learning (ML) algorithms and improve on them by investigating more sophisticated ML approaches. We find that nonlinear algorithms and clustering methods produce significantly higher assignment fidelities that help close the gap to the fidelity possible under ideal noise conditions. Clustering methods group trajectories into natural subsets within the data, which allows for the diagnosis of systematic errors. We find large clusters in the data associated with T1 processes and show these are the main source of discrepancy between our experimental and ideal fidelities. These error diagnosis techniques help provide a path forward to improve qubit measurements.

  14. Dynamical Mass Measurements of Contaminated Galaxy Clusters Using Machine Learning

    NASA Astrophysics Data System (ADS)

    Ntampaka, M.; Trac, H.; Sutherland, D. J.; Fromenteau, S.; Póczos, B.; Schneider, J.

    2016-11-01

    We study dynamical mass measurements of galaxy clusters contaminated by interlopers and show that a modern machine learning algorithm can predict masses by better than a factor of two compared to a standard scaling relation approach. We create two mock catalogs from Multidark’s publicly available N-body MDPL1 simulation, one with perfect galaxy cluster membership information and the other where a simple cylindrical cut around the cluster center allows interlopers to contaminate the clusters. In the standard approach, we use a power-law scaling relation to infer cluster mass from galaxy line-of-sight (LOS) velocity dispersion. Assuming perfect membership knowledge, this unrealistic case produces a wide fractional mass error distribution, with a width of {{Δ }}ε ≈ 0.87. Interlopers introduce additional scatter, significantly widening the error distribution further ({{Δ }}ε ≈ 2.13). We employ the support distribution machine (SDM) class of algorithms to learn from distributions of data to predict single values. Applied to distributions of galaxy observables such as LOS velocity and projected distance from the cluster center, SDM yields better than a factor-of-two improvement ({{Δ }}ε ≈ 0.67) for the contaminated case. Remarkably, SDM applied to contaminated clusters is better able to recover masses than even the scaling relation approach applied to uncontaminated clusters. We show that the SDM method more accurately reproduces the cluster mass function, making it a valuable tool for employing cluster observations to evaluate cosmological models.

  15. The multiphysics analysis of the metallic bipolar plate by the electrochemical micro-machining fabrication process

    NASA Astrophysics Data System (ADS)

    Lee, Yu-Ming; Lee, Shuo-Jen; Lee, Chi-Yuan; Chang, Dar-Yuan

    In this study, the flow channels of a PEM fuel cell are fabricated by the EMM process. The parametric effects of the process are studied by both numerical simulation and experimental tests. For the numerical simulation, the multiphysics model, consisting of electrical field, convection, and diffusion phenomena is applied using COMSOL software. COMSOL software is used to predict the parametric effects of the channel fabrication accuracy such as pulse rate, pulse duty cycle, inter-electrode gap and electrolytic inflow velocity. The proper experimental parameters and the relationship between the parameters and the distribution of metal removal are established from the simulated results. The experimental fabrication tests showed that a shorter pulse rate and a higher pulse current improved the fabrication accuracy, and is consistent with the numerical simulation results. The proposed simulation model could be employed as a predictive tool to provide optimal parameters for better machining accuracy and process stability of the EMM process.

  16. Measuring large aspherics using a commercially available 3D-coordinate measuring machine

    NASA Astrophysics Data System (ADS)

    Otto, Wolfgang; Matthes, Axel; Schiehle, Heinz

    2000-07-01

    A CNC-controlled precision measuring machine is a very powerful tool in the optical shop not only to determine the surface figure, but also to qualify the radius of curvature and conic constant of aspherics. We used a commercially available 3D-coordinate measuring machine (CMM, ZEISS UPMC 850 CARAT S-ACC) to measure the shape of the GEMINI 1-m convex secondary mirrors at different lapping and polishing stages. To determine the measuring accuracy we compared the mechanical measurements with the results achieved by means of an interferometrical test setup. The data obtained in an early stage of polishing were evaluated in Zernike polynomials which show a very good agreement. The deviation concerning long wave rotational symmetrical errors was 20 nm rms, whereas the accuracy measuring of mid spatial frequency deviations was limited to about 100 nm rms.

  17. Force plate for measuring small animal forces by digital speckle pattern interferometry

    NASA Astrophysics Data System (ADS)

    Arroyo, M. Pilar; Bea, José Antonio; Andrés, Nieves; Osta, Rosario; Doblaré, Manuel

    2007-06-01

    This paper presents a force plate specially designed for measuring ground reaction forces in small animals. Digital Speckle Pattern Interferometry (DSPI) is used to measure the plate deformation produced by the animal. Elasticity theory is used to obtain force magnitude and application position from the vertical displacement field measured with DSPI. The force plate has been tested with static weights of 5g and 10g at various locations on the plate. Some experiments with 20g body weight transgenic mice are also reported.

  18. A simple procedure to include a free-form measurement capability to standard coordinate measurement machines

    NASA Astrophysics Data System (ADS)

    Schneider, Florian; Rascher, Rolf; Stamp, Richard; Smith, Gordon

    2013-09-01

    The modern optical industry requires objects with complex topographical structures. Free-form shaped objects are of large interest in many branches, especially for size reduced, modern lifestyle products like digital cameras. State of the art multi-axes-coordinate measurement machines (CMM), like the topographical measurement machine TII-3D, are by principle suitable to measure free-form shaped objects. The only limitation is the software package. This paper may illustrate a simple way to enhance coordinate measurement machines in order to add a free-form function. Next to a coordinate measurement machine, only a state of the art CAD† system and a simple piece of software are necessary. For this paper, the CAD software CREO‡ had been used. CREO enables the user to develop a 3D object in two different ways. With the first method, the user might design the shape by drawing one or more 2D sketches and put an envelope around. Using the second method, the user could define one or more formulas in the editor to describe the favoured surface. Both procedures lead to the required three-dimensional shape. However, further features of CREO enable the user to export the XYZ-coordinates of the created surface. A special designed software tool, developed with Matlab§, converts the XYZ-file into a measurement matrix which can be used as a reference file. Finally the result of the free-form measurement, carried out with a CMM, has to be loaded into the software tool and both files will be computed. The result is an error profile which provides the deviation between the measurement and the target-geometry.

  19. Hold-computer vision for direct measurement of flexural strains in plates

    NASA Astrophysics Data System (ADS)

    Hung, Y. Y.

    Marriage of holographic interferometry and digital image processing technique allows direct measurement of flexural strains in plates. By digitally multiplying a holographic carrier fringe pattern of the deformed plate with the same but rotated 180 deg, a moire fringe pattern of an ellipse or hyperbola is produced. The principal axes measure directly the principal strain components at the point of rotation.

  20. An application of CCD read-out technique to neutron distribution measurement using the self-activation method with a CsI scintillator plate

    NASA Astrophysics Data System (ADS)

    Nohtomi, Akihiro; Kurihara, Ryosuke; Kinoshita, Hiroyuki; Honda, Soichiro; Tokunaga, Masaaki; Uno, Heita; Shinsho, Kiyomitsu; Wakabayashi, Genichiro; Koba, Yusuke; Fukunaga, Junichi; Umezu, Yoshiyuki; Nakamura, Yasuhiko; Ohga, Saiji

    2016-10-01

    In our previous paper, the self-activation of an NaI scintillator had been successfully utilized for detecting photo-neutrons around a high-energy X-ray radiotherapy machine; individual optical pulses from the self-activated scintillator are read-out by photo sensors such as a photomultiplier tube (PMT). In the present work, preliminary observations have been performed in order to apply a direct CCD read-out technique to the self-activation method with a CsI scintillator plate using a Pu-Be source and a 10-MV linac. In conclusion, it has been revealed that the CCD read-out technique is applicable to neutron measurement around a high-energy X-ray radiotherapy machine with the self-activation of a CsI plate. Such application may provide a possibility of novel method for simple neutron dose-distribution measurement.

  1. A new dual-plate slipometer for measuring slip between molten polymers and extrusion die materials.

    PubMed

    Schmalzer, A M; Giacomin, A J

    2014-04-01

    In this work, we study the slip behaviors common to plastics die extrusion metals or platings using a new instrument called a dual-plate slipometer. By dual-plate, we mean that whereas the stationary plate incorporates a local shear stress transducer, the moving plate does not. The stationary plate and transducer are made of one stainless steel, but the moving plate is made from, or plated with, different extrusion die materials under study. This new instrument allows slip velocity to be measured without having to build a new shear stress transducer from each extrusion metal or plating under study. We explore the effect of extrusion die composition and die metal surface morphology on the slip properties of polyolefins using a sliding plate rheometer. In this work, we studied the slip behaviors of polyolefins on four common plastics die extrusion metals or platings, without having to build a new shear stress transducer from each. Specifically, our new method replaces the moving plate; with each of the four die metals or platings under study without changing the stainless steel material of the shear stress transducer and its stationary plate. Our experiments include high-density polyethylene, low-density polyethylene, and polypropylene (PP) on four different die metals or platings. We use steady simple shear to obtain shear stress versus nominal shear rate for different gaps, from which we can then deduce the slip velocity using the Mooney analysis. We then fit four slip models to our experimental measurements, and we find the Hatzikiriakos hyperbolic sine model to be accurate, even for the measured inflections in the slip velocity as a function of shear stress curves. Our analysis includes detailed characterization of the die metal plating surfaces, including measurements of the composition of the sliding plates by energy dispersive spectroscopy, surface energy by contact angle goniometry, and surface roughness by both white light interference and stylus

  2. Application of a virtual coordinate measuring machine for measurement uncertainty estimation of aspherical lens parameters

    NASA Astrophysics Data System (ADS)

    Küng, Alain; Meli, Felix; Nicolet, Anaïs; Thalmann, Rudolf

    2014-09-01

    Tactile ultra-precise coordinate measuring machines (CMMs) are very attractive for accurately measuring optical components with high slopes, such as aspheres. The METAS µ-CMM, which exhibits a single point measurement repeatability of a few nanometres, is routinely used for measurement services of microparts, including optical lenses. However, estimating the measurement uncertainty is very demanding. Because of the many combined influencing factors, an analytic determination of the uncertainty of parameters that are obtained by numerical fitting of the measured surface points is almost impossible. The application of numerical simulation (Monte Carlo methods) using a parametric fitting algorithm coupled with a virtual CMM based on a realistic model of the machine errors offers an ideal solution to this complex problem: to each measurement data point, a simulated measurement variation calculated from the numerical model of the METAS µ-CMM is added. Repeated several hundred times, these virtual measurements deliver the statistical data for calculating the probability density function, and thus the measurement uncertainty for each parameter. Additionally, the eventual cross-correlation between parameters can be analyzed. This method can be applied for the calibration and uncertainty estimation of any parameter of the equation representing a geometric element. In this article, we present the numerical simulation model of the METAS µ-CMM and the application of a Monte Carlo method for the uncertainty estimation of measured asphere parameters.

  3. Imperfection and Thickness Measurement of Panels Using a Coordinate Measurement Machine

    NASA Technical Reports Server (NTRS)

    Thornburgh, Robert P.

    2006-01-01

    This paper summarizes the methodology used to measure imperfection and thickness variation for flat and curved panels using a Coordinate Measurement Machine (CMM) and the software program MeasPanel. The objective is to provide a reference document so that someone with a basic understanding of CMM operation can measure a panel with minimal training. Detailed information about both the measurement system setup and computer software is provided. Information is also provided about the format of the raw data, as well as how it is post-processed for use in finite-element analysis.

  4. Machine vision technique for measuring glass container thickness

    NASA Astrophysics Data System (ADS)

    Ford, Ralph M.; Mercier, Jeffrey A.

    2003-05-01

    The inspection of sidewall thickness provides important information about the production processes for glass container manufacture. By monitoring the thickness profile around the perimeter of bottles in real-time, the manufacturing process can be altered to produce higher quality products. This also provides the ability to identify and remove defective products. In order to improve the speed and accuracy of inspections, a new non-contact method for acquiring thickness profiles of glass bottles that employs optical and machine vision techniques has been developed and tested. One of the fundamental laws of optics, Snell's Law, is the basic concept upon which the inspection technique relies. The thickness of a flat plane of transparent material can be determined from Snell"s Law with a single beam of light that passes through the medium, reflects off the secondary surface, and travels back to the initial surface and passes through it. Based upon this principle, a new non-contact glass thickness measurement technique has been developed and it has demonstrated good accuracy.

  5. High-accuracy thickness measurement of a transparent plate with the heterodyne central fringe identification technique

    SciTech Connect

    Wu, Wang-Tsung; Hsieh, Hung-Chih; Chang, Wei-Yao; Chen, Yen-Liang; Su, Der-Chin

    2011-07-20

    In a modified Twyman-Green interferometer, the optical path variation is measured with the heterodyne central fringe identification technique, as the light beam is focused by a displaced microscopic objective on the front/rear surface of the test transparent plate. The optical path length variation is then measured similarly after the test plate is removed. The geometrical thickness of the test plate can be calculated under the consideration of dispersion effect. This method has a wide measurable range and a high accuracy in the measurable range.

  6. High-accuracy thickness measurement of a transparent plate with the heterodyne central fringe identification technique.

    PubMed

    Wu, Wang-Tsung; Hsieh, Hung-Chih; Chang, Wei-Yao; Chen, Yen-Liang; Su, Der-Chin

    2011-07-20

    In a modified Twyman-Green interferometer, the optical path variation is measured with the heterodyne central fringe identification technique, as the light beam is focused by a displaced microscopic objective on the front/rear surface of the test transparent plate. The optical path length variation is then measured similarly after the test plate is removed. The geometrical thickness of the test plate can be calculated under the consideration of dispersion effect. This method has a wide measurable range and a high accuracy in the measurable range.

  7. High-accuracy thickness measurement of a transparent plate with the heterodyne central fringe identification technique

    NASA Astrophysics Data System (ADS)

    Wu, Wang-Tsung; Hsieh, Hung-Chih; Chang, Wei-Yao; Chen, Yen-Liang; Su, Der-Chin

    2011-07-01

    In a modified Twyman--Green interferometer, the optical path variation is measured with the heterodyne central fringe identification technique, as the light beam is focused by a displaced microscopic objective on the front/rear surface of the test transparent plate. The optical path length variation is then measured similarly after the test plate is removed. The geometrical thickness of the test plate can be calculated under the consideration of dispersion effect. This method has a wide measurable range and a high accuracy in the measurable range.

  8. Integration of Error Compensation of Coordinate Measuring Machines into Feature Measurement: Part I-Model Development.

    PubMed

    Calvo, Roque; D'Amato, Roberto; Gómez, Emilio; Domingo, Rosario

    2016-09-29

    The development of an error compensation model for coordinate measuring machines (CMMs) and its integration into feature measurement is presented. CMMs are widespread and dependable instruments in industry and laboratories for dimensional measurement. From the tip probe sensor to the machine display, there is a complex transformation of probed point coordinates through the geometrical feature model that makes the assessment of accuracy and uncertainty measurement results difficult. Therefore, error compensation is not standardized, conversely to other simpler instruments. Detailed coordinate error compensation models are generally based on CMM as a rigid-body and it requires a detailed mapping of the CMM's behavior. In this paper a new model type of error compensation is proposed. It evaluates the error from the vectorial composition of length error by axis and its integration into the geometrical measurement model. The non-explained variability by the model is incorporated into the uncertainty budget. Model parameters are analyzed and linked to the geometrical errors and uncertainty of CMM response. Next, the outstanding measurement models of flatness, angle, and roundness are developed. The proposed models are useful for measurement improvement with easy integration into CMM signal processing, in particular in industrial environments where built-in solutions are sought. A battery of implementation tests are presented in Part II, where the experimental endorsement of the model is included.

  9. Integration of Error Compensation of Coordinate Measuring Machines into Feature Measurement: Part I—Model Development

    PubMed Central

    Calvo, Roque; D’Amato, Roberto; Gómez, Emilio; Domingo, Rosario

    2016-01-01

    The development of an error compensation model for coordinate measuring machines (CMMs) and its integration into feature measurement is presented. CMMs are widespread and dependable instruments in industry and laboratories for dimensional measurement. From the tip probe sensor to the machine display, there is a complex transformation of probed point coordinates through the geometrical feature model that makes the assessment of accuracy and uncertainty measurement results difficult. Therefore, error compensation is not standardized, conversely to other simpler instruments. Detailed coordinate error compensation models are generally based on CMM as a rigid-body and it requires a detailed mapping of the CMM’s behavior. In this paper a new model type of error compensation is proposed. It evaluates the error from the vectorial composition of length error by axis and its integration into the geometrical measurement model. The non-explained variability by the model is incorporated into the uncertainty budget. Model parameters are analyzed and linked to the geometrical errors and uncertainty of CMM response. Next, the outstanding measurement models of flatness, angle, and roundness are developed. The proposed models are useful for measurement improvement with easy integration into CMM signal processing, in particular in industrial environments where built-in solutions are sought. A battery of implementation tests are presented in Part II, where the experimental endorsement of the model is included. PMID:27690052

  10. High-speed measurements of steel-plate deformations during laser surface processing.

    PubMed

    Jezersek, Matija; Gruden, Valter; Mozina, Janez

    2004-10-04

    In this paper we present a novel approach to monitoring the deformations of a steel plate's surface during various types of laser processing, e.g., engraving, marking, cutting, bending, and welding. The measuring system is based on a laser triangulation principle, where the laser projector generates multiple lines simultaneously. This enables us to measure the shape of the surface with a high sampling rate (80 Hz with our camera) and high accuracy (+/-7 microm). The measurements of steel-plate deformations for plates of different thickness and with different illumination patterns are presented graphically and in an animation.

  11. Study on technology of double parallel-joints coordinate measuring machine

    NASA Astrophysics Data System (ADS)

    Xia, Guisuo; Liao, Cheng; Yu, Runqiao; Fu, Yanjun

    2013-10-01

    The research of the high accuracy coordinate measuring machine is now playing a more and more considerable role in heightening the technical level of equipment manufacturing industry. With reference to the characteristics of foreign ScanMax coordinate measuring machine, this paper introduces the development of a double parallel-joint coordinate measuring machine with our own dependent intellectual property. This paper details the structural design, the calibration method and the evaluation for the uncertainty measurement of a prototype. The prototype has several advantages when compared with foreign instruments: first, decrease of Abbe error; second, enlargement of the measuring range; third, improvement of the rigidity of the instrument. The measurement test indicates that the measurement uncertainty (when K=2) of special random distance is 10.2 μm. The double parallel-joint coordinate measuring machine studied by this paper is of great academic value and the developed prototype is highly practical and worthy of being popularized.

  12. Plate boundary segmentation in the northeastern Caribbean from geodetic measurements and Neogene geological observations

    NASA Astrophysics Data System (ADS)

    Calais, Éric; Symithe, Steeve; Mercier de Lépinay, Bernard; Prépetit, Claude

    2016-01-01

    The Caribbean-North America plate boundary in the northeastern Caribbean shows a remarkable example of along-strike transition from plate boundary-normal subduction in the Lesser Antilles, oblique subduction with no strain partitioning in Puerto Rico, and oblique subduction/collision with strain partitioning further west in Hispaniola. We show that this segmentation is well marked in the interseismic strain, as measured using space geodetic data, and in the Neogene deformation regime, as derived from geological observations. Hence, interseismic segmentation, which reproduces the geological segmentation persistent over a long time interval, is inherited from the geological history and long-term properties of the plate boundary. This result is relevant to the assessment of seismic hazard at convergent plate boundaries, where geodetic measurements often show interseismic segmentation between fully-and partially-coupled plate interface regions.

  13. Theoretical analysis based on fundamental functions of thin plate and experimental measurement for vibration characteristics of a plate coupled with liquid

    NASA Astrophysics Data System (ADS)

    Liao, Chan-Yi; Wu, Yi-Chuang; Chang, Ching-Yuan; Ma, Chien-Ching

    2017-04-01

    This study combined theoretical, experimental, and numerical analysis to investigate the vibration characteristics of a thin rectangular plate positioned horizontally at the bottom of a rectangular container filled with liquid. Flow field pressure was derived using an equation governing the behavior of incompressible fluids. Analytic solutions to vibrations in a thin plate in air served as the fundamental function of the thin plate coupled with liquid. We then used liquid pressure, and the out-of-plane deflection of the thin plate for the construction of frequency response functions for the analysis of vibration characteristics in the liquid-plate coupling system. Two experimental methods were employed to measure the vibration characteristics of the thin plate immersed in water. The first involved using sensors of polyvinylidene difluoride (PVDF) to measure transient signals of fluid-plate system subjected an impact at the thin plate. These were then converted to the frequency domain in order to obtain the resonant frequencies of the fluid-plate coupling system. The second method was amplitude-fluctuation electronic speckle pattern interferometry (AF-ESPI), which was used to measure the dynamic characteristics of the thin plate in the flow field. This method was paired with the image processing techniques, temporal speckle pattern interferometry (TSPI) and temporal standard deviation (TSTD), to obtain clear mode shapes of the thin plate and resonant frequencies. Comparison of the results from theoretical analysis, finite element method, and experimental measurements confirmed the accuracy of our theoretical analysis, which was superior to the conventional approach based on beam mode shape functions. The experimental methods proposed in this study can be used to measure the resonant frequencies of underwater thin plates, and clear mode shapes can be obtained using AF-ESPI. Our results indicate that the resonant frequencies of thin plates underwater are lower than

  14. Aerodynamic Measurements on a Large Splitter Plate for the NASA Langley Transonic Dynamics Tunnel

    NASA Technical Reports Server (NTRS)

    Schuster, David M.

    2001-01-01

    Tests conducted in the NASA Langley Research Center Transonic Dynamics Tunnel (TDT) assess the aerodynamic characteristics of a splitter plate used to test some semispan models in this facility. Aerodynamic data are analyzed to determine the effect of the splitter plate on the operating characteristics of the TDT, as well as to define the range of conditions over which the plate can be reasonably used to obtain aerodynamic data. Static pressures measurements on the splitter plate surface and the equipment fairing between the wind tunnel wall and the splitter plate are evaluated to determine the flow quality around the apparatus over a range of operating conditions. Boundary layer rake data acquired near the plate surface define the viscous characteristics of the flow over the plate. Data were acquired over a range of subsonic, transonic and supersonic conditions at dynamic pressures typical for models tested on this apparatus. Data from this investigation should be used as a guide for the design of TDT models and tests using the splitter plate, as well as to guide future splitter plate design for this facility.

  15. Numerical and experimental demonstration of shear stress measurement at thick steel plates using acoustoelasticity

    NASA Astrophysics Data System (ADS)

    Abbasi, Zeynab; Ozevin, Didem

    2015-04-01

    The purpose of this article is to numerically quantify the stress state of complex loaded thick steel plates using the fundamental theory of acoustoelasticity, which is the relationship with stress and ultrasonic velocity in the nonlinear regime. The normal and shear stresses of a thick plate can be measured using a phased array placement of ultrasonic sensors and Rayleigh ultrasonic waves. Three measurement angles (i.e., 0 45 and 90 degrees) are selected since three measurements are needed to solve the stress tensor in an isotropic plate. The ultrasonic data is influenced significantly by the frequency of the Rayleigh waves as well as the thickness of the plate being examined; consequently the overall experimental process is influenced by the measurement parameters. In this study, a numerical demonstration is implemented to extract the nonlinearity coefficients using a 3D structural geometry and Murnaghan material model capable of examining the effects of various plate thicknesses and ultrasonic frequencies on the shear stress measurement. The purpose is that as the thickness becomes smaller, the shear stress becomes negligible at the angled measurement. For thicker cross section, shear stress becomes influential if the depth of penetration of Rayleigh wave is greater than the half of the thickness. The correlation between the depth of penetration and shear stress is then obtained. The numerical results are compared with 1 MHz ultrasonic frequency and a 3/8 inch thick steel plate loaded uniaxially while the measurement direction is angled to have the presence of shear stress in the measurement direction.

  16. Phishtest: Measuring the Impact of Email Headers on the Predictive Accuracy of Machine Learning Techniques

    ERIC Educational Resources Information Center

    Tout, Hicham

    2013-01-01

    The majority of documented phishing attacks have been carried by email, yet few studies have measured the impact of email headers on the predictive accuracy of machine learning techniques in detecting email phishing attacks. Research has shown that the inclusion of a limited subset of email headers as features in training machine learning…

  17. Multiplexed chemiluminescent assays in ArrayPlates for high-throughput measurement of gene expression

    NASA Astrophysics Data System (ADS)

    Martel, Ralph R.; Rounseville, Matthew P.; Botros, Ihab W.; Seligmann, Bruce E.

    2002-06-01

    Multiplexed Molecular Profiling (MMP) assays for drug discovery are performed in ArrayPlates. ArrayPlates are 96- well microtiter plates that contain a 16-element array at the bottom of each well. Each element within an array measures one analyte in a sample. A CCD imager records the quantitative chemiluminescent readout of all 1,536 elements in a 96-well plate simultaneously. Since array elements are reagent modifiable by the end-user, ArrayPlates can be adapted to a broad range of nucleic acid- and protein-based assays. Such multiplexed assays are rapidly established, flexible, robust, automation-friendly and cost-effective. Nucleic acid assays in ArrayPlates can detect DNA and RNA, including SNPs and ESTs. A multiplexed mRNA assay to measure the expression of 16 genes is described. The assay combines a homogeneous nuclease protection assay with subsequent probe immobilization to the array by means of a sandwich hybridization followed with chemiluminescent detection. This assay was used to examine cells grown and treated in microplates and avoided cloning, transfection, RNA insolation, reverse transcription, amplification and fluorochrome labeling. Standard deviations for the measurement of 16 genes ranged from 3 percent to 13 percent in samples of 30,000 cells. Such ArrayPlates transcription assays are useful in drug discovery and development for target validation, screening, lead optimization, metabolism and toxicity profiling. Chemiluminescent detection provides ArrayPlates assays with high signal-to-noise readout and simplifies imager requirements. Imaging a 2D surface that contains arrays simplifies lens requirements relative to imaging columns of liquid in microtiter plate wells. The Omix imager for ArrayPlates is described.

  18. Precision mechatronics based on high-precision measuring and positioning systems and machines

    NASA Astrophysics Data System (ADS)

    Jäger, Gerd; Manske, Eberhard; Hausotte, Tino; Mastylo, Rostyslav; Dorozhovets, Natalja; Hofmann, Norbert

    2007-06-01

    Precision mechatronics is defined in the paper as the science and engineering of a new generation of high precision systems and machines. Nanomeasuring and nanopositioning engineering represents important fields of precision mechatronics. The nanometrology is described as the today's limit of the precision engineering. The problem, how to design nanopositioning machines with uncertainties as small as possible will be discussed. The integration of several optical and tactile nanoprobes makes the 3D-nanopositioning machine suitable for various tasks, such as long range scanning probe microscopy, mask and wafer inspection, nanotribology, nanoindentation, free form surface measurement as well as measurement of microoptics, precision molds, microgears, ring gauges and small holes.

  19. Operational modal analysis of a rectangular plate using non-contact excitation and measurement

    NASA Astrophysics Data System (ADS)

    Xu, Y. F.; Zhu, W. D.

    2013-09-01

    Operational modal analysis (OMA), or output-only modal analysis, has been extensively developed in the past decades and widely used especially when the input is unknown and difficult to measure. This paper presents a non-contact experimental technique for measuring modal parameters of a rectangular aluminum plate with free boundaries using only the output data, with the intention to apply the technique to turbine blades. OMA is used to analyze both the out-of-plane and in-plane vibrations of the plate in the frequency range of up to 15,000 Hz, which can be an operation frequency range of a turbine blade, under white noise acoustic excitation in a direction of interest. It is shown that OMA can be performed when the types of measurement at the measurement and reference points are different, since the associated cross-correlation functions contain modal characteristics of the test structure. A single-point laser vibrometer and a free-field microphone are used to simultaneously measure the responses of the plate in a non-contact manner, with the microphone measurement serving as the reference. The pressure measured by the microphone near the reference point is shown to be proportional to the normal surface acceleration at the reference point, and the cross power spectral densities obtained by the current test method can be used for modal parameter estimation. A method for measuring the in-plane modes of the plate by shining the laser beam on the plate surface with an incident angle is developed. Experimental modal analysis (EMA) is also performed on the plate using an impact hammer and the laser vibrometer. The measured natural frequencies and mode shapes of the out-of-plane and in-plane modes of the plate using OMA and EMA are compared with those calculated using commercial finite element software. The maximum error between the measured and calculated natural frequencies of the plate is 1.53 percent for the first 18 elastic modes, including 16 out-of-plane and two in

  20. [Laser and vision measurement research on parameters of miniature quartz plate-sensitive glass part].

    PubMed

    Wang, Xin; Zhang, Xiao-Dong

    2014-06-01

    High-precision, rapid and non-contact geometry parameter measurements of plate glass parts has become a main problem in the field of testing-related production and processing and also an important applied direction for laser spectroscopy. Accurately detect the geometric parameters of plate glass parts can not only improve the processing technology and the precision of assembly, but also bring about sub-file management according to the parameters. This paper presents a novel multi-parameter measurement method based on the laser and vision image processing technology, which can be used to measure parameters of miniature quartz plate-sensitive glass part accurately. The testing system consisting of self-adaption coaxial visual detection unit and laser vision thickness inspection unit was designed. A constant power drive control system was set up to ensure the laser diode (LD) can provide a stable light source for the testing system. A modified sub-pixel edge position algorithm of conic features was proposed to implement the sub-pixel image processing, and the parameters can be extracted. According to the data detected from curve edge points and a new-defined error function, which was minimized, the parameters of miniature quartz plate-sensitive glass part can be calculated. The experiments show that the average deviation of the measurement results is less than 2 υm, and the method has good stability and high accuracy measurement, which can meet the precision requirement of parameter measurement for miniature plate glass part.

  1. A new deformation measurement method for heavy-duty machine tool base by multipoint distributed FBG sensors

    NASA Astrophysics Data System (ADS)

    Li, Ruiya; Tan, Yuegang; Liu, Yi; Zhou, Zude; Liu, Mingyao

    2015-10-01

    The deformation of machine tool base is one of main error elements of heavy-duty CNC machine tool. A new deformation measurement method for heavy-duty machine tool base by multipoint distributed FBG sensors is developed in this study. Experiment is implemented on a real moving beam gantry machine tool. 16 FBG strain sensors are installed on the side-surface of the machine tool base. Moving the machine tool column to different positions, varying strain signals are collected. The testing results show that this distributed measurement method based on FBG sensors can effectively detect the deformation of the machine tool base. The largest deflection in vertical direction (axis Z) can be 75μm. This work is of great significance to the structure optimizing of machine tool base and real-time error compensation of heavy-duty CNC machine tool.

  2. Temperature alters solute transport in growth plate cartilage measured by in vivo multiphoton microscopy

    PubMed Central

    Serrat, Maria A.; Williams, Rebecca M.; Farnum, Cornelia E.

    2009-01-01

    Solute delivery to avascular cartilaginous plates is critical to bone elongation, and impaired transport of nutrients and growth factors in cartilage matrix could underlie many skeletal abnormalities. Advances in imaging technology have revolutionized our ability to visualize growth plates in vivo, but quantitative methods are still needed. We developed analytical standards for measuring solute delivery, defined by amount and rate of intravenous tracer entry, in murine growth plates using multiphoton microscopy. We employed an acute temperature model because of its well-established impact on bone circulation and tested the hypothesis that solute delivery changes positively with limb temperature when body core and respiration are held constant (36°C, 120 breaths/min). Tibial growth plates were surgically exposed in anesthetized 5-wk-old mice, and their hindlimbs were immersed in warm (36°C) or cool (23°C) saline (n = 6/group). After 30 min of thermal equilibration, we administered an intracardiac injection of fluorescein (50 μl, 0.5%) and captured sequentially timed growth plate images spanning 10 min at standardized depth. Absolute growth plate fluorescence was normalized to vascular concentrations for interanimal comparisons. As predicted, more fluorescein infiltrated growth plates at 36°C, with standardized values nearly double those at 23°C. Changing initial limb temperature did not alter baseline values, suggesting a sustained response period. These data validate the sensitivity of our system and have relevance to strategies for enhancing localized delivery of therapeutic agents to growth plates of children. Applications of this technique include assessment of solute transport in models of growth plate dysfunction, particularly chondrodysplasias with matrix irregularities. PMID:19372302

  3. Integration of Error Compensation of Coordinate Measuring Machines into Feature Measurement: Part II—Experimental Implementation

    PubMed Central

    Calvo, Roque; D’Amato, Roberto; Gómez, Emilio; Domingo, Rosario

    2016-01-01

    Coordinate measuring machines (CMM) are main instruments of measurement in laboratories and in industrial quality control. A compensation error model has been formulated (Part I). It integrates error and uncertainty in the feature measurement model. Experimental implementation for the verification of this model is carried out based on the direct testing on a moving bridge CMM. The regression results by axis are quantified and compared to CMM indication with respect to the assigned values of the measurand. Next, testing of selected measurements of length, flatness, dihedral angle, and roundness features are accomplished. The measurement of calibrated gauge blocks for length or angle, flatness verification of the CMM granite table and roundness of a precision glass hemisphere are presented under a setup of repeatability conditions. The results are analysed and compared with alternative methods of estimation. The overall performance of the model is endorsed through experimental verification, as well as the practical use and the model capability to contribute in the improvement of current standard CMM measuring capabilities. PMID:27754441

  4. Measuring the usefulness of hidden units in Boltzmann machines with mutual information.

    PubMed

    Berglund, Mathias; Raiko, Tapani; Cho, Kyunghyun

    2015-04-01

    Restricted Boltzmann machines (RBMs) and deep Boltzmann machines (DBMs) are important models in deep learning, but it is often difficult to measure their performance in general, or measure the importance of individual hidden units in specific. We propose to use mutual information to measure the usefulness of individual hidden units in Boltzmann machines. The measure is fast to compute, and serves as an upper bound for the information the neuron can pass on, enabling detection of a particular kind of poor training results. We confirm experimentally that the proposed measure indicates how much the performance of the model drops when some of the units of an RBM are pruned away. We demonstrate the usefulness of the measure for early detection of poor training in DBMs.

  5. [Theoretical analysis and experimental measurement for secondary electron yield of microchannel plate in extreme ultraviolet region].

    PubMed

    Li, Min; Ni, Qi-liang; Dong, Ning-ning; Chen, Bo

    2010-08-01

    Photon counting detectors based on microchannel plate have widespread applications in astronomy. The present paper deeply studies secondary electron of microchannel plate in extreme ultraviolet. A theoretical model describing extreme ultraviolet-excited secondary electron yield is presented, and the factor affecting on the secondary electron yields of both electrode and lead glass which consist of microchannel plate is analyzed according to theoretical formula derived from the model. The result shows that the higher secondary electron yield is obtained under appropriate condition that the thickness of material is more than 20 nm and the grazing incidence angle is larger than the critical angle. Except for several wavelengths, the secondary electron yields of both electrode and lead glass decrease along with the increase in the wavelength And also the quantum efficiency of microchannel plate is measured using quantum efficiency test set-up with laser-produced plasmas source as an extreme ultraviolet radiation source, and the result of experiment agrees with theoretical analysis.

  6. Design and Development of ZigBee Based Instantaneous Flat-plate Collector Efficiency Measurement System

    NASA Astrophysics Data System (ADS)

    Vairamani, K.; Venkatesh, K. Arun; Mathivanan, N.

    2011-01-01

    Computing the efficiency of flat-plate collector is vital in solar thermal system testing. This paper presents the design of ZigBee enabled data acquisition system for instantaneous flat-plate collector efficiency calculation. It involves measurement of parameters like inlet and outlet fluid temperatures, ambient temperature and solar radiation intensity. The designed system has a base station and a sensor node. ZigBee wireless communication protocol is used for communication between the base station and the sensor node for wireless data acquisition. The wireless sensor node which is mounted over the collector plate includes the necessary sensors and associated signal-conditioners. An application program has been developed on LabVIEW platform for data acquisition, processing and analysis and is executed in base station PC. Instantaneous flat-plate collector efficiency is computed and reported.

  7. A rapid, valid and inexpensive assay for measuring epiphyseal plates in mouse tibia.

    PubMed

    Interlichia, Jillian P; Williams, Nolann G; Rodgers, Buel D

    2010-04-01

    One of the most accurate indices of changes in somatic tissue growth rate in rodents is the width of tibial epiphyseal plates as unlike most mammals, rodent growth plates never ossify. Unfortunately, the original procedure to measure tibial epiphyseal plate width (TEPW) was developed for rats and yields poor results with mice. This paper demonstrates a simple method for silver staining growth plates that can be used to inexpensively and quickly measure the TEPW of mice. Poor visualization due to overstaining and the shattering of growth plates necessitated several revisions to the original protocol. These include exposing the growth plate prior to acetone dehydration, reducing the silver nitrate concentration from 2% to 1.5% and staining time from 2 min to 10 s and finally, the use of reflective light rather than transmissive light when imaging. The optimized protocol was then validated by generating an age-dependent TEPW growth curve that matched changes in tibia length. A total of 120 tibias were processed in a combined time of less than one day and for less than $30. By contrast, histological processing in the university's core facility would have cost $1440 and taken approximately three weeks. Thus, the revised protocol is vastly more cost effective, reliable and can be performed considerably quicker with minimal training.

  8. A force plate system for measuring low-magnitude reaction forces in small laboratory animals.

    PubMed

    Handley, D E; Ross, J F; Carr, G J

    1998-07-01

    We present a force plate system which measures low-magnitude vertical reaction forces generated by small laboratory animals. The force plate mechanical design minimizes radiated transverse waves, acoustic reverberation, and standing waves caused by impacts on the force plate surface. A secondary force plate and PC-based software algorithm minimize floor vibrational artifact. The force plate was used to measure function of rats during two tests: forelimb/hindlimb hopping reaction and surface righting reaction. In control rats, forelimb hopping rate exceeded hindlimb hopping rate during 16 weeks of repeated testing. Subchronic intraperitoneal (i.p.) dosing of 10 mg/kg/day acrylamide produced a selective impairment of hindlimb hopping. In contrast, single doses of haloperidol (1-5 mg/kg, i.p.) slowed the righting reaction and produced a relatively selective impairment of forelimb hopping. The force plate system presents new opportunities for performing quantitative neurological assessments of small laboratory animals when previously such tests had been performed subjectively and qualitatively.

  9. Z-correction, a method for achieving ultraprecise self-calibration on large area coordinate measurement machines for photomasks

    NASA Astrophysics Data System (ADS)

    Ekberg, Peter; Stiblert, Lars; Mattsson, Lars

    2014-05-01

    High-quality photomasks are a prerequisite for the production of flat panel TVs, tablets and other kinds of high-resolution displays. During the past years, the resolution demand has become more and more accelerated, and today, the high-definition standard HD, 1920 × 1080 pixels2, is well established, and already the next-generation so-called ultra-high-definition UHD or 4K display is entering the market. Highly advanced mask writers are used to produce the photomasks needed for the production of such displays. The dimensional tolerance in X and Y on absolute pattern placement on these photomasks, with sizes of square meters, has been in the range of 200-300 nm (3σ), but is now on the way to be <150 nm (3σ). To verify these photomasks, 2D ultra-precision coordinate measurement machines are used with even tighter tolerance requirements. The metrology tool MMS15000 is today the world standard tool used for the verification of large area photomasks. This paper will present a method called Z-correction that has been developed for the purpose of improving the absolute X, Y placement accuracy of features on the photomask in the writing process. However, Z-correction is also a prerequisite for achieving X and Y uncertainty levels <90 nm (3σ) in the self-calibration process of the MMS15000 stage area of 1.4 × 1.5 m2. When talking of uncertainty specifications below 200 nm (3σ) of such a large area, the calibration object used, here an 8-16 mm thick quartz plate of size approximately a square meter, cannot be treated as a rigid body. The reason for this is that the absolute shape of the plate will be affected by gravity and will therefore not be the same at different places on the measurement machine stage when it is used in the self-calibration process. This mechanical deformation will stretch or compress the top surface (i.e. the image side) of the plate where the pattern resides, and therefore spatially deform the mask pattern in the X- and Y-directions. Errors due

  10. Using financial risk measures for analyzing generalization performance of machine learning models.

    PubMed

    Takeda, Akiko; Kanamori, Takafumi

    2014-09-01

    We propose a unified machine learning model (UMLM) for two-class classification, regression and outlier (or novelty) detection via a robust optimization approach. The model embraces various machine learning models such as support vector machine-based and minimax probability machine-based classification and regression models. The unified framework makes it possible to compare and contrast existing learning models and to explain their differences and similarities. In this paper, after relating existing learning models to UMLM, we show some theoretical properties for UMLM. Concretely, we show an interpretation of UMLM as minimizing a well-known financial risk measure (worst-case value-at risk (VaR) or conditional VaR), derive generalization bounds for UMLM using such a risk measure, and prove that solving problems of UMLM leads to estimators with the minimized generalization bounds. Those theoretical properties are applicable to related existing learning models.

  11. NONDESTRUCTIVE MEASUREMENT OF MOISTURE CONTENT USING A PARALLEL-PLATE CAPACITANCE SENSOR FOR GRAIN AND NUTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A simple, low cost instrument that measures impedance and phase angle was used along with a parallel-plate capacitance system to estimate the moisture content (MC) of in-shell peanuts and yellow field corn. Moisture content of the field crops is important and is measured at various stages of their ...

  12. Design of Stress-Strain Measuring System for Bulldozing Plate Based on Virtual Instrument Technology

    NASA Astrophysics Data System (ADS)

    Xu, S. C.; Li, J. Q.; Zhang, R.

    2006-10-01

    Soil is a kind of discrete, multiphase compound that is composed of soil particles, liquid and air. When soil is disturbed by bulldozing plate, the mechanical behavior of the soil will become very complex. Based on the law of action and reaction, the dynamic mechanical behavior of disturbed soil was indirectly analyzed by measuring and studying the forces on the bulldozing plate by soil currently, so a stress-strain virtual measuring system for bulldozing plate, which was designed by the graphical programming language DASYLab, was used to measure the horizontal force Fz acting on the bulldozing plate. In addition, during the course of design, the experimental complexities and the interferential factors influencing on signal logging were analyzed when bulldozing plate worked, so the anti-jamming methods of hardware and software technology were adopted correlatively. In the end, the horizontal force Fz was analyzed with Error Theory, the result shown that the quantificational analysis of Fz were identical to the qualitative results of soil well, and the error of the whole test system is under 5 percent, so the tress-strain virtual measuring system was stable and credible.

  13. Theory of probe measurements at the divertor plate

    SciTech Connect

    Porter, G.D.; Ryutov, D.D.

    1996-12-31

    Probe measurements represent a technically simple and inexpensive approach to the characterization of plasma parameters in the divertor region. On the other hand, the interpretation of the probe signals is sometimes not straightforward, with discrepancies between the results of probe measurements and Thomson scattering measurements often arising. The difficulty of interpretation of probe measurements stems predominantly from the unknown influence of a strong magnetic field on the probe current-voltage characteristics (CVC). There have been many studies of this issue, among the most recent ones papers. In our paper, we present analysis of the physics issues which determine the performance of so called {open_quotes}flush mounted probes{close_quotes}. We note that, in case of an infinitely strong magnetic field, the flux-tube whose footprint coincides with the probe surface, is completely isolated from the rest of the plasma, and the probe CVC becomes more similar to the CVC of a double probe. As a next step in the analysis, we consider classical cross-field transport processes and conclude that, for the flux tubes with dimensions of a few ion gyroradii (as is the case for the probes of the type used in DMD) the cross-field currents are dominated by the ion viscosity. We derive the probe CVC for this case and find that it has a remarkable similarity with the aforementioned characteristics of the double probe. We consider possible effects of plasma turbulence on the cross field transport through a thin flux tube leaning on the probe. We conclude that the character of this effect strongly depends on the spatial and temporal scale of the plasma fluctuations: the influence of fast short-wavelength fluctuations can be described in terms of enhanced diffusion across the flux tube, while the influence of the slow ones can not. As the SOL turbulence is usually slow, we consider in more detail the effect of slow fluctuations.

  14. Laboratory arrangement for soft x-ray zone plate efficiency measurements

    SciTech Connect

    Bertilson, Michael C.; Takman, Per A. C.; Holmberg, Anders; Vogt, Ulrich; Hertz, Hans M.

    2007-02-15

    We demonstrate a laboratory-scale arrangement for rapid and accurate measurements of the absolute and local efficiency of soft x-ray micro zone plates in the water window. This in-house instrument is based on a single-line {lambda}=2.88 nm liquid-jet laser-plasma source. Measurements are performed by a simultaneous comparison of first diffraction-order photon flux with the flux in a calibrated reference signal. This arrangement eliminates existing source emission fluctuations. The performance of the method is demonstrated by the result from measurements of two {approx}55 {mu}m diameter nickel micro zone plates, showing a groove efficiency of 12.9%{+-}1.1% and 11.7%{+-}1.0%. Furthermore, we show that spatially resolved efficiency mapping is an effective tool for a detailed characterization of local zone plate properties. Thus, this laboratory-scale instrument allows rapid feedback to the fabrication process which is important for future improvements.

  15. The Interpretation of Dynamic Contact Angles Measured by the Wilhelmy Plate Method

    PubMed

    Ramé

    1997-01-01

    We present an analysis for properly interpreting apparent dynamic contact angles measured using the Wilhelmy plate method at low capillary numbers, Ca. This analysis removes the ambiguity in current dynamic measurements which interpret data with the same formula as static measurements. We properly account for all forces, including viscous forces, acting on the plate as it moves into or out of a liquid bath. Our main result, valid at O(1) as Ca --> 0, relates the apparent dynamic contact angle to material-dependent, geometry-independent parameters necessary for describing dynamic wetting of a system. The special case of the apparent contact angle = pi/2 was solved to O(Ca). This O(Ca) solution can guide numerical work necessary for higher Ca's and arbitrary values of the apparent contact angle. These results make the Wilhelmy plate a viable method for determining material parameters for dynamic spreading.

  16. An automatic system for measurement of retardation of wave plates based on phase-shifted method

    NASA Astrophysics Data System (ADS)

    Gao, Zhishan; Yan, Ming

    2005-02-01

    A practical system is described to measure the retardation of wave plates with phase-shifted method. The tested wave plate is put in and the original angle between the axis of it and the analyzer is random, not 45 degree. For the measurement is made rapidly and automatically, a standard wave plate act as a compensator, the stepping motor is used to drive the analyzer to realize phase shifting and a grating encoder is used to measure its rotating angle. At the same time, while the beam comes out from the analyzer, the photoelectric detector gets its intensity, and then the signals is magnified, filtered and sent to computer through its serial port. The results show the system has the advantages of costing little time and high accuracy.

  17. Phase Velocity Method for Guided Wave Measurements in Composite Plates

    NASA Astrophysics Data System (ADS)

    Moreno, E.; Galarza, N.; Rubio, B.; Otero, J. A.

    Carbon Fiber Reinforced Polymer is a well-recognized material for aeronautic applications. Its plane structure has been widely used where anisotropic characteristics should be evaluated with flaw detection. A phase velocity method of ultrasonic guided waves based on a pitch-catch configuration is presented for this purpose. Both shear vertical (SV) and shear horizontal (SH) have been studied. For SV (Lamb waves) the measurements were done at different frequencies in order to evaluate the geometrical dispersion and elastic constants. The results for SV are discussed with an orthotropic elastic model. Finally experiments with lamination flaws are presented.

  18. Machine integrated optical measurement of honed surfaces in presence of cooling lubricant

    NASA Astrophysics Data System (ADS)

    Schmitt, R.; König, N.; Zheng, H.

    2011-08-01

    The measurement of honed surfaces is one of the most important tasks in tribology. Although many established techniques exist for texture characterization, such as SEM, tactile stylus or white-light interferometry, none of them is suited for a machine integrated measurement. Harsh conditions such as the presence of cooling lubricant or vibrations prohibit the use of commercial sensors inside a honing machine. Instead, machined engine blocks need time-consuming cleaning and preparation while taken out of the production line for inspection. A full inspection of all produced parts is hardly possible this way. Within this paper, an approach for a machine-integrated measurement is presented, which makes use of optical sensors for texture profiling. The cooling lubricant here serves as immersion medium. The results of test measurements with a chromatic-confocal sensor and a fiber-optical low-coherence interferometer show the potential of both measuring principles for our approach. Cooling lubricant temperature and flow, scanning speed and measurement frequency have been varied in the tests. The sensor with best performance will later be chosen for machine integration.

  19. Phase-locked loop based on machine surface topography measurement using lensed fibers.

    PubMed

    Kang, Jin-Ho; Lee, ChaBum; Joo, Jae-Young; Lee, Sun-Kyu

    2011-02-01

    We present the phase-locked loop (PLL)-based metrology concept using lensed fibers for on-machine surface topography measurement. The shape of a single-mode fiber at the endface was designed using an ABCD matrix method, and two designed lensed fibers-the ball type and the tapered type-were fabricated, and the performance was evaluated, respectively. As a result, the interferometric fringe was not found in the case of the ball lensed fiber, but the machined surface could be measured by utilization of autofocusing and intensity methods. On the other hand, a very clear Fizeau interferometric fringe was observed in the case of the tapered lensed fiber. Its performance was compared with the results of the capacitance sensor and a commercially available white-light interferometer. We confirmed that PLL-based surface profile measurement using the tapered and ball lensed fibers can be applied for on-machine surface topography measurement applications.

  20. Phase-locked loop based on machine surface topography measurement using lensed fibers

    SciTech Connect

    Kang, Jin-Ho; Lee, ChaBum; Joo, Jae-Young; Lee, Sun-Kyu

    2011-02-01

    We present the phase-locked loop (PLL)-based metrology concept using lensed fibers for on-machine surface topography measurement. The shape of a single-mode fiber at the endface was designed using an ABCD matrix method, and two designed lensed fibers--the ball type and the tapered type--were fabricated, and the performance was evaluated, respectively. As a result, the interferometric fringe was not found in the case of the ball lensed fiber, but the machined surface could be measured by utilization of autofocusing and intensity methods. On the other hand, a very clear Fizeau interferometric fringe was observed in the case of the tapered lensed fiber. Its performance was compared with the results of the capacitance sensor and a commercially available white-light interferometer. We confirmed that PLL-based surface profile measurement using the tapered and ball lensed fibers can be applied for on-machine surface topography measurement applications.

  1. A method of measuring the velocity of slit based on machine vision

    NASA Astrophysics Data System (ADS)

    Chen, Man; Liao, Zhijie

    2017-01-01

    In the lithography machine, there is a field diaphragm, which is a kind of edge structure. In the process of exposure, it is linearly synchronous movement with the die, so when developing the slit, it is necessary to measure its movement characteristics precisely. A method of velocity measurement based on machine vision is adopted, by detecting edge position in sequential images, and then through the transformation between image coordinate and world coordinate, the object displacement in real space is calculated and finally instantaneous velocity of the object is got. Firstly, through the simulation model in CODE V, correctness of the measurement principle is verified, Next, some error sources that affect the precision of the machine vision measurement system are analyzed, and corresponding solutions are given.

  2. Research on performance evaluation of non-arm coordinate measuring machine (NACMM)

    NASA Astrophysics Data System (ADS)

    Wang, Weinong; Wei, Hengzheng; Xia, Yang

    2010-11-01

    The methods for performance evaluation of Articulated Arm Coordinate Measuring Machine (AACMM) have been published. Non-arm Coordinate Measuring Machine (NACMM) is similar with AACMM in function, and then the performance evaluation methods should be also similar. The research based on comparing the principle and error resources of the both systems, set up a new combination of the position, orientation and test number, try to locate a more reasonable procedure in evaluate the performance of NACMMs which can be comparable with ASME B89.4.22-2004, but better for find the characteristic of accuracy changing in measurement volume. The procedure is confirmed by testing of different NACMMs.

  3. The simplest chronoscope II: reaction time measured by meterstick versus machine.

    PubMed

    Montare, Alberto

    2010-12-01

    Visual simple reaction time (SRT) scores measured in 31 college students of both sexes by use of the simplest chronoscope methodology (meterstick SRT) were compared to scores obtained by use of an electromechanical multi-choice reaction timer (machine SRT). Four hypotheses were tested. Results indicated that the previous mean value of meterstick SRT was replicated; meterstick SRT was significantly faster than long-standing population estimates of mean SRT; and machine SRT was significantly slower than the same long-standing mean SRT estimates for the population. Also, the mean meterstick SRT of 181 msec. was significantly faster than the mean machine SRT of 294 msec. It was theorized that differential visual information processing occurred such that the dorsal visual stream subserved meterstick SRT; whereas the ventral visual stream subserved machine SRT.

  4. Measurements of displacement around holes in composite plates subjected to quasi-static compression

    NASA Technical Reports Server (NTRS)

    Duke, J. C., Jr.; Post, D.; Czarnek, R.; Asundi, A.

    1982-01-01

    Attempts to develop a whole-field, high sensitivity optical technque for measurement of load induced changes of thickness of composite plates are described. Graphite-epoxy plates of quasi-isotropic layup were used as test specimens. Changes of thickness of three plates, each with a central hole of different size, were measured as a function of applied compressive loads. The first test specimen showed localized zones where no holographic fringes were present, surrounded by zones of low fringe contrast. This was thought to be a result of localized motion or creep. Subsequent tests with an increased time interval between specimen loading and holographic exposure demonstrated no localized zones of absent fringes. No plausible explanation for radical differences in the quality of fringe patterns was found, although the use of specimens having a high quality mirrorized surface provided superior change of thickness patterns. Recommendations for further investigations and changes in test procedure are presented.

  5. Results of error correction techniques applied on two high accuracy coordinate measuring machines

    SciTech Connect

    Pace, C.; Doiron, T.; Stieren, D.; Borchardt, B.; Veale, R.; National Inst. of Standards and Technology, Gaithersburg, MD )

    1990-01-01

    The Primary Standards Laboratory at Sandia National Laboratories (SNL) and the Precision Engineering Division at the National Institute of Standards and Technology (NIST) are in the process of implementing software error correction on two nearly identical high-accuracy coordinate measuring machines (CMMs). Both machines are Moore Special Tool Company M-48 CMMs which are fitted with laser positioning transducers. Although both machines were manufactured to high tolerance levels, the overall volumetric accuracy was insufficient for calibrating standards to the levels both laboratories require. The error mapping procedure was developed at NIST in the mid 1970's on an earlier but similar model. The error mapping procedure was originally very complicated and did not make any assumptions about the rigidness of the machine as it moved, each of the possible error motions was measured at each point of the error map independently. A simpler mapping procedure was developed during the early 1980's which assumed rigid body motion of the machine. This method has been used to calibrate lower accuracy machines with a high degree of success and similar software correction schemes have been implemented by many CMM manufacturers. The rigid body model has not yet been used on highly repeatable CMMs such as the M48. In this report we present early mapping data for the two M48 CMMs. The SNL CMM was manufactured in 1985 and has been in service for approximately four years, whereas the NIST CMM was delivered in early 1989. 4 refs., 5 figs.

  6. Air-coupled ultrasonic through-transmission thickness measurements of steel plates.

    PubMed

    Waag, Grunde; Hoff, Lars; Norli, Petter

    2015-02-01

    Non-destructive ultrasonic testing of steel structures provide valuable information in e.g. inspection of pipes, ships and offshore structures. In many practical applications, contact measurements are cumbersome or not possible, and air-coupled ultrasound can provide a solution. This paper presents air-coupled ultrasonic through-transmission measurements on a steel plate with thicknesses 10.15 mm; 10.0 mm; 9.8 mm. Ultrasound pulses were transmitted from a piezoelectric transducer at normal incidence, through the steel plate, and were received at the opposite side. The S1, A2 and A3 modes of the plate are excited, with resonance frequencies that depend on the material properties and the thickness of the plate. The results show that the resonances could be clearly identified after transmission through the steel plate, and that the frequencies of the resonances could be used to distinguish between the three plate thicknesses. The S1-mode resonance was observed to be shifted 10% down compared to a simple plane wave half-wave resonance model, while the A2 and S2 modes were found approximately at the corresponding plane-wave resonance frequencies. A model based on the angular spectrum method was used to predict the response of the through-transmission setup. This model included the finite aperture of the transmitter and receiver, and compressional and shear waves in the solid. The model predicts the frequencies of the observed modes of the plate to within 1%, including the down-shift of the S1-mode.

  7. Double-layer PVDF transducer and V(z) measurement system for measuring leaky Lamb waves in a piezoelectric plate.

    PubMed

    Lee, Yung-Chun; Kuo, Shi Hoa

    2007-03-01

    This paper presents a new experimental measurement method for leaky Lamb waves propagating in a piezoelectric plate immersed in a conductive fluid. The measurement system is a low-frequency version of lens-less acoustic microscopy which has been developed based on a line-focus double-layer PVDF transducer. The transducer and its defocusing measurement system can perform V(z) measurements on a sample plate immersed in a fluid, and therefore can obtain the leaky Lamb wave velocities with high accuracy. An X-cut LiNbO(3) plate is investigated with this experimental measurement system to find out its fluid-loading effects, especially the conductive loading effects by water of various conductivities. Angular dependence of this conductive loading effect along different propagating directions on the X-cut LiNbO(3) plate is measured. It is found out the conductive loading effects are strongly dependent on the piezoelectric coupling factor. Theoretical calculations based on partial wave theory have also been carried out and compared with experimental data. Good agreements have been observed.

  8. Rigid two-axis MEMS force plate for measuring cellular traction force

    NASA Astrophysics Data System (ADS)

    Takahashi, Hidetoshi; Jung, Uijin G.; Kan, Tetsuo; Tsukagoshi, Takuya; Matsumoto, Kiyoshi; Shimoyama, Isao

    2016-10-01

    Cellular traction force is one of the important factors for understanding cell behaviors, such as spreading, migration and differentiation. Cells are known to change their behavior according to the mechanical stiffness of the environment. However, the measurement of cell traction forces on a rigid environment has remained difficult. This paper reports a micro-electromechanical systems (MEMS) force plate that provides a cellular traction force measurement on a rigid substrate. Both the high force sensitivity and high stiffness of the substrate were obtained using piezoresistive sensing elements. The proposed force plate consists of a 70 µm  ×  15 µm  ×  5 µm base as the substrate for cultivating a bovine aortic smooth muscle cell, and the supporting beams with piezoresistors on the sidewall and the surface were used to measure the forces in both the horizontal and vertical directions. The spring constant and force resolution of the fabricated force plate in the horizontal direction were 0.2 N m-1 and less than 0.05 µN, respectively. The cell traction force was measured, and the traction force increased by approximately 1 µN over 30 min. These results demonstrate that the proposed force plate is applicable as an effective traction force measurement.

  9. Equation of State Measurements of Liquid Deuterium Subject to Magnetically Driven Hypervelocity Plate Impact

    NASA Astrophysics Data System (ADS)

    Knudson, Marcus; Hanson, David; Bailey, Jim; Hall, Clint; Asay, Jim; Lemke, Ray; Oliver, Bryan

    2000-10-01

    Recently a new capability has been developed at Sandia National Laboratories to isentropically compress materials to high pressures using magnetic pressure produced by the Sandia Z accelerator. Along with this new capability comes the ability of using this technique to launch relatively large flyer plates (9-12 mm in diameter by 200-300 micron thickness) to velocities in excess of conventional gas gun and HVL technologies. This technique for performing shock wave experiments using the Z accelerator is particularly attractive for several reasons. First, the experiments are plate impact experiments, and thus produce a well defined pressure loading of the sample, with a finite duration of constant pressure and no pre-conditioning of the sample prior to shock arrival. Second, the relatively large flyer plates allow for large sample diameters (several mm) and thicknesses (on the order of 1 mm), thus increasing the accuracy of the measurements. Finally, the geometry of the experiment allows for up to 8 flyer plates to be launched in a single firing of the Z accelerator allowing for multiple experiments and redundant measurements to be made. Initial shock wave experiments using this magnetically driven hypervelocity flyer plate technique have been performed on liquid deuterium using an impedance matching technique. Results of initial experiments will be discussed. The possibility of using the flyer pate technique for generating warm, dense matter and well defined plasma states will also be discussed.

  10. Rigid and flexible endoscopes for three dimensional measurement of inside machine parts using fringe projection

    NASA Astrophysics Data System (ADS)

    Pösch, Andreas; Schlobohm, Jochen; Matthias, Steffen; Reithmeier, Eduard

    2017-02-01

    Routine maintenance is mandatory for safe and efficient operation of complex machines, such as airplane turbines. Occasional special events, like bird strike, entail extraordinary inspection works. Hereby, inside machine parts are hard to reach, oftentimes occluded by other parts and not directly accessible for visual inspection. Disassembly of machine parts is time-consuming and expensive and, therefore undesired. This leaves distal imaging, i.e. endoscopy, to be the only practical option for defect detection. Ordinary endoscopes, which provide two dimensional intensity image data, are insufficient to fully assess the risks caused by small three dimensional defects. As a solution to this issue, we have developed and implemented two different systems for three dimensional endoscopic measurement based on structured light projection which are capable of recording high resolution and high accuracy point cloud data. A measurement standard deviation of roughly 20 μm is achieved within a field of measurement of 20 × 30 × 30mm3 .

  11. Field and laboratory calibration of impact plates for measuring coarse bed load transport

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During 2008-2009, an array of impact plates instrumented with either accelerometers or geophones was installed over a channel spanning weir in the Elwha River in Washington, USA. The impact system is the first permanent installation of its kind in North America. The system was deployed to measure th...

  12. Installation of Impact Plates to Continuously Measure Bed Load: Elwha River, Washington, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2008 and 2009, a series of bed load impact plates was installed across a channel spanning weir on the Elwha River, Washington. This is the first permanent installation of its kind in North America and one of the largest anywhere. The purpose of this system is to measure coarse bed load during and...

  13. Skin friction and Reynolds stress measurements for a turbulent boundary layer following manipulation using flat plates

    NASA Technical Reports Server (NTRS)

    Westphal, R. V.

    1986-01-01

    Research has been undertaken to experimentally study the alterations in turbulent boundary-layer properties due to turbulence manipulation using thin flat plates. Plate geometry and placement within the boundary layer were selected to coincide with recent studies. Direct, local measurements of skin friction and Reynolds stresses were made within the boundary layer downstream of the manipulator devices for cases with an approach momentum thickness Reynolds number of 3700. A strong tendency for recovery of the Reynolds stresses was observed, accompanied by local skin-friction reductions of up to 15 percent. The mean velocity profile in the manipulated flow displayed the same similarity shape in the logarithmic region as a natural boundary layer, but had an enhanced wake component. The results indicate that the plate wake plays an important role in the boundary layer response to this sort of manipulation.

  14. Measurement of the Casimir force between Germanium plates using a torsion balance

    SciTech Connect

    Dalvit, Diego; Kim, W J; Sushkov, A O; Lamoreaux, S K

    2008-01-01

    We report the measurement of the Casimir force between Ge plates in a sphere-plane configuration using a torsion balance. We observe that the effective contact potential between the plates varies with their separation distance, resulting in a systematic force. In addition, an unexpected 1/d force is also found in our data that persists even when the electrostatic force between the plates is experimentally minimized by applying a compensating potential. After applying corrections due to these systematic forces, likely of electrostatic origin, our result can be described by the bare permittivity of Ge without conduction, the Drude and the diffusion models for electrical and optical properties of Ge, but not by the plasma model.

  15. Measurement of displacement using phase shifted wedge plate lateral shearing interferometry

    NASA Astrophysics Data System (ADS)

    Disawal, Reena; Prakash, Shashi

    2016-03-01

    In present communication, a simple technique for measurement of displacement using phase shifted wedge plate lateral shearing interferometry is described. The light beam from laser is expanded and illuminates a wedge plate of relatively large angle. Light transmitted through the wedge plate is converged onto a reflecting specimen using a focusing lens. Back-reflected wavefront from the specimen is incident on the wedge plate. Because of the tilt and shear of the wavefront reflected from the wedge plate, typical straight line fringes appear. These fringes are superimposed onto a sinusoidal grating forming a moiré pattern. The orientation of the moiré fringes is a function of specimen displacement. Four step phase shifting test procedure has been incorporated by translating the grating in phase steps of π/2. Necessary mathematical formulation to establish correlation between the 'difference phase' and the displacement of the specimen surface is undertaken. The technique is automatic and provides resolution and expanded uncertainty of 1 μm and 0.246 μm, respectively. Detailed uncertainty analysis is also reported.

  16. Indirect measurement of machine tool motion axis error with single laser tracker

    NASA Astrophysics Data System (ADS)

    Wu, Zhaoyong; Li, Liangliang; Du, Zhengchun

    2015-02-01

    For high-precision machining, a convenient and accurate detection of motion error for machine tools is significant. Among common detection methods such as the ball-bar method, the laser tracker approach has received much more attention. As a high-accuracy measurement device, laser tracker is capable of long-distance and dynamic measurement, which increases much flexibility during the measurement process. However, existing methods are not so satisfactory in measurement cost, operability or applicability. Currently, a plausible method is called the single-station and time-sharing method, but it needs a large working area all around the machine tool, thus leaving itself not suitable for the machine tools surrounded by a protective cover. In this paper, a novel and convenient positioning error measurement approach by utilizing a single laser tracker is proposed, followed by two corresponding mathematical models including a laser-tracker base-point-coordinate model and a target-mirror-coordinates model. Also, an auxiliary apparatus for target mirrors to be placed on is designed, for which sensitivity analysis and Monte-Carlo simulation are conducted to optimize the dimension. Based on the method proposed, a real experiment using single API TRACKER 3 assisted by the auxiliary apparatus is carried out and a verification experiment using a traditional RENISHAW XL-80 interferometer is conducted under the same condition for comparison. Both results demonstrate a great increase in the Y-axis positioning error of machine tool. Theoretical and experimental studies together verify the feasibility of this method which has a more convenient operation and wider application in various kinds of machine tools.

  17. Comparison of intra individual physiological sway complexity from force plate and inertial measurement unit - biomed 2013.

    PubMed

    Soangra, Rahul; Lockhart, Thurmon E

    2013-01-01

    Center of Pressure (COP) is a clinical measure to investigate the effect of sensory input disturbances on postural stability in the healthy, elderly population as well in people suffering from neuromuscular disease. Increased center of pressure velocity and sway area are interpreted as decreased stability or poor balance and are associated with fall risk. Body mounted inertial sensors have shown great promise as an easily implemented clinical measure of balance. The aim of the present study is to investigate if force-plate and accelerometer measurements provide similar physiological information when approximate entropy (ApEn) are evaluated from a time series. Seven young and thirteen older individuals (two with fall history and nine without any past fall) participated in this study. There were different complexity measures in healthy young and elderly participants when both force-plate and Inertial Measurement Unit (IMU) were assessed during the same time interval. Thus different control mechanisms are underlying to control trunk sway as measured by IMU than that of COP measured by force-plate.

  18. Thickness measurement system for transparent plates using dual digital versatile disc (DVD) pickups.

    PubMed

    Liu, Chien-Hung; Yeh, Shien-Chang; Huang, Hsueh-Liang

    2010-02-01

    A low-cost high-precision thickness measurement system for transparent plates that uses dual digital versatile disc (DVD) pickups is proposed. The two DVD pickups are used as the transmitter and the receiver in the measurement system, respectively. One of the DVD pickups emits a laser to the other DVD pickup (receiver) and projects on the photodiode integrated circuit of the receiver. The transparent plate is placed in the optical path to change the focused point that will affect the focusing error signal (FES) of the receiver. Using the FES, a mathematical model for thickness measurement based on the geometric optical method is developed. The experimental results show that the accuracy is 1.5 microm, and the uncertainty is estimated to be +/-1.37 microm for the measured thickness of 150 microm.

  19. Thickness measurement system for transparent plates using dual digital versatile disc (DVD) pickups

    SciTech Connect

    Liu, Chien-Hung; Yeh, Shien-Chang; Huang, Hsueh-Liang

    2010-02-01

    A low-cost high-precision thickness measurement system for transparent plates that uses dual digital versatile disc (DVD) pickups is proposed. The two DVD pickups are used as the transmitter and the receiver in the measurement system, respectively. One of the DVD pickups emits a laser to the other DVD pickup (receiver) and projects on the photodiode integrated circuit of the receiver. The transparent plate is placed in the optical path to change the focused point that will affect the focusing error signal (FES) of the receiver. Using the FES, a mathematical model for thickness measurement based on the geometric optical method is developed. The experimental results show that the accuracy is 1.5 {mu}m, and the uncertainty is estimated to be {+-}1.37 {mu}m for the measured thickness of 150{mu}m.

  20. Normal contour error measurement on-machine and compensation method for polishing complex surface by MRF

    NASA Astrophysics Data System (ADS)

    Chen, Hua; Chen, Jihong; Wang, Baorui; Zheng, Yongcheng

    2016-10-01

    The Magnetorheological finishing (MRF) process, based on the dwell time method with the constant normal spacing for flexible polishing, would bring out the normal contour error in the fine polishing complex surface such as aspheric surface. The normal contour error would change the ribbon's shape and removal characteristics of consistency for MRF. Based on continuously scanning the normal spacing between the workpiece and the finder by the laser range finder, the novel method was put forward to measure the normal contour errors while polishing complex surface on the machining track. The normal contour errors was measured dynamically, by which the workpiece's clamping precision, multi-axis machining NC program and the dynamic performance of the MRF machine were achieved for the verification and security check of the MRF process. The unit for measuring the normal contour errors of complex surface on-machine was designed. Based on the measurement unit's results as feedback to adjust the parameters of the feed forward control and the multi-axis machining, the optimized servo control method was presented to compensate the normal contour errors. The experiment for polishing 180mm × 180mm aspherical workpiece of fused silica by MRF was set up to validate the method. The results show that the normal contour error was controlled in less than 10um. And the PV value of the polished surface accuracy was improved from 0.95λ to 0.09λ under the conditions of the same process parameters. The technology in the paper has been being applied in the PKC600-Q1 MRF machine developed by the China Academe of Engineering Physics for engineering application since 2014. It is being used in the national huge optical engineering for processing the ultra-precision optical parts.

  1. Application of a positioning and measuring machine for metrological long-range scanning force microscopy

    NASA Astrophysics Data System (ADS)

    Hausotte, T.; Jaeger, G.; Manske, E.; Hofmann, N.; Dorozhovets, N.

    2005-08-01

    This article deals with a high-precision three-dimensional positioning and measuring machine and its application as a metrological long-range scanning force microscope. At the Institute of Process Measurement and Sensor Technology of the Technische Universitaet Ilmenau an interferometric nanopositioning and nanomeasuring machine has been developed. Which is able to achieve a resolution of less than 0.1 nm over the entire positioning and measurement range of 25 mm x 25 mm x 5 mm and is traceable to the length standard. The Abbe offset-free design in conjunction with a corner mirror as a reference coordinate system provides extraordinary accuracy. The integration of several probe systems and nanotools (AFM, STM, focus sensor, tactile probes) makes the nanopositioning and nanomeasuring machine suitable for various tasks in the micro- and nanotechnologies. Various probe systems have been integrated in the last few years. For example, a commercial piezo tube AFM was integrated and tested. Additionally, interferometeric measurement systems of the nanopositioning and nanomeasuring machine enables the calibration of probe systems. Also in order to achieve the best possible measurement results special probe systems have been developed and tested and are discussed briefly.

  2. Measurement of birefringence of optical materials using a wedged plate interferometer

    NASA Technical Reports Server (NTRS)

    Shukla, R. P.; Perera, G. M.; George, M. C.; Venkateswarlu, Putcha

    1990-01-01

    A nondestructive technique for measuring the birefringence of optical materials such as calcite using wedged plate interferometer is presented. The sample needed for measuring the refractive index must be polished in the form of a parallel plate. The method is based on the measurement of the longitudinal displacement of the focus when the parallel plate is inserted in a converging beam of light. The displacement of the focus is a measure of the refractive index of the optical material. In the case of a uniaxial crystal, the displacement of the focus for the extraordinary ray is different from the displacement of the focus for the ordinary ray. Hence the birefringence of the crystal is determined by measuring the difference between the two focii. It is possible to obtain an accuracy up to 0.0002 in the measurement of birefringence depending on the sample thickness. The method should find its application for the characterization of new crystals in various material research and crystal growth laboratories.

  3. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Control of laser machining of polycrystalline diamond plates by the method of low-coherence optical interferometry

    NASA Astrophysics Data System (ADS)

    Kononenko, Vitalii V.; Konov, Vitalii I.; Pimenov, S. M.; Volkov, P. V.; Goryunov, A. V.; Ivanov, V. V.; Novikov, M. A.; Markelov, V. A.; Tertyshnik, A. D.; Ustavshchikov, S. S.

    2005-07-01

    The possibility of applying low-coherence fibre optics interferometry for local contactless measurement of the optical thickness of polycrystalline diamond plates during high-power laser-pulse processing of their rough surface is demonstrated. A unique automated experimental system is developed to control the thickness of samples during ablation of their surface by a scanning 248-nm KrF excimer laser beam. It is shown that this technique is suitable for on-line control of laser polishing and for preparing plane-parallel plates.

  4. Laser damage measurement of thick silica plates using a new laser injection scheme

    NASA Astrophysics Data System (ADS)

    Penninckx, D.; Diaz, R.; Bonville, O.; Courchinoux, R.; Lamaignère, L.; Luce, J.

    2016-07-01

    Some silica plates of high power nanosecond lasers may be a few centimeter thick for instance because they should sustain vacuum. Measuring laser-induced damage thresholds at the output surface of these thick silica plates is a complex task because non-linear laser propagation effects may occur inside the plate which prevents knowing accurately the fluence at the output. Two non-linear effects have to be considered: stimulated Brillouin scattering (SBS) and Kerr effect. SBS is mainly driven by the spectral power density of the pulses: if the spectral power density is below a threshold, SBS is negligible. Thus, spectral broadening is required. Kerr effect depends on the instantaneous intensity. Hence, a smooth temporal shape without overshoots is required. However, both conditions (wide spectrum and no overshoots) are impossible to fulfill with standard lasers. As a matter of fact, an injected laser has a smooth temporal profile but is spectrally narrow. Without injection, the laser is multimode yielding a wide spectrum but a chaotic temporal profile. We solved the problem by phase-modulating a continuous-wave seeder of our laser (patent pending). The phasemodulation frequency is adjusted to a multiple of the inverse of the round-trip time of the laser cavity. The laser pulses have a wide spectrum to suppress SBS and do not exhibit temporal overshoots to reduce Kerr effects. During the presentation, we will show the features of the laser pulses and laser-induced damage measurements of thick silica plates using this scheme.

  5. 96-Well plate assays for measuring collagenase activity using (3)H-acetylated collagen.

    PubMed

    Koshy, P J; Rowan, A D; Life, P F; Cawston, T E

    1999-11-15

    We describe two alternative assays for measuring collagenolytic activity using (3)H-acetylated collagen. Both assays have been developed for the 96-well plate format and measure the amount of radiolabeled collagen fragments released into the supernatant from an insoluble (3)H-acetylated collagen fibril preparation. The first method separates digested solubilized fragments from the intact fibril by sedimentation of the undigested collagen by centrifugation. The second method achieves this separation by filtration of the supernatant through the membrane of a 96-well filtration plate which retains the undigested collagen fibril. Both methods give linear dose- and time-dependent responses of collagenase activity > or = 70% of total collagen lysis. In addition, both assays can be simply modified to measure tissue inhibitors of metalloproteinases (TIMPs) inhibitory activity, which is also linear between 20 and 75% of total collagen lysis with the amount of TIMP added.

  6. Installation and Implementation of an In-Process Coordinate Measuring Machine (CMM)

    SciTech Connect

    Johnston, Derek

    2008-06-16

    This report documents the work accomplished during the installation and implementation of the in-process Coordinate Measuring Machine (CMM) in Department A. A wealth of knowledge has been gained in solving the many technical issues that delayed the partial implementation of this CMM. The work completed thus far lead to the successfully calibrated in-process CMM workstation. A great deal of current and future work has been outlined in the following pages that shall be used as a guide for the full implementation of this CMM with machining processes in Department A.

  7. The inversion method in measuring noise emitted by machines in opencast mines of rock material.

    PubMed

    Pleban, Dariusz; Piechowicz, Janusz; Kosała, Krzysztof

    2013-01-01

    The inversion method was used to test vibroacoustic processes in large-size machines used in opencast mines of rock material. When this method is used, the tested machine is replaced with a set of substitute sources, whose acoustic parameters are determined on the basis of sound pressure levels and phase shift angles of acoustic signals, measured with an array of 24 microphones. This article presents test results of a combine unit comprising a crusher and a vibrating sieve, for which an acoustic model of 7 substitute sources was developed with the inversion method.

  8. Temperature of Heating and Cooling of Massive, Thin, and Wedge-Shaped Plates from Hard-to-Machine Steels During Their Grinding

    NASA Astrophysics Data System (ADS)

    Dement‧ev, V. B.; Ivanova, T. N.; Dolginov, A. M.

    2017-01-01

    Grinding of flat parts occurs by solid abrasive particles due to the physicomechanical process of deformation and to the action of a process liquid at high temperatures in a zone small in volume and difficult for observation. The rate of heating and cooling depends on the change in the intensity of the heat flux and in the velocity and time of action of the heat source. A study has been made of the regularities of the influence of each of these parameters on the depth and character of structural transformations during the grinding of flat parts from hard-to-machine steels. A procedure to calculate temperature in grinding massive, thin, and wedge-shaped parts has been developed with account taken of the geometric and thermophysical parameters of the tool and the treated part, and also of cutting regimes. The procedure can be used as a constituent part in developing a system for automatic design of the technological process of grinding of flat surfaces. A relationship between the temperature in the grinding zone and the regimes of treatment has been established which makes it possible to control the quality of the surface layer of massive, thin, and wedge-shaped plates from hard-to-machine steels. The rational boundaries of shift of cutting regimes have been determined.

  9. About one algorithm of the broken line approximation and a modeling of tool path for CNC plate cutting machines

    NASA Astrophysics Data System (ADS)

    Kurennov, D. V.; Petunin, A. A.; Repnitskii, V. B.; Shipacheva, E. N.

    2016-12-01

    The problem of approximating two-dimensional broken line with composite curve consisting of arc and line segments is considered. The resulting curve nodes have to coincide with source broken line nodes. This problem arises in the development of control programs for CNC (computer numerical control) cutting machines, permitting circular interpolation. An original algorithm is proposed minimizing the number of nodes for resulting composite curve. The algorithm is implemented in the environment of the Russian CAD system T-Flex CAD using its API (Application Program Interface). The algorithm optimality is investigated. The result of test calculation along with its geometrical visualization is given.

  10. Damage identification in plates using vibratory power estimated from measured accelerations

    NASA Astrophysics Data System (ADS)

    Huh, Young Cheol; Chung, Tae Young; Lee, Jong Won; Kim, Jae Kwan

    2015-02-01

    Vibratory power is defined as the rate of energy transmitted through a cross section of unit width in a vibrating structure. It is known that the vibratory power is a function of the source and travel path. Therefore the spatial distribution of the vibratory power may contain information on the state of a structure. Vibratory power can be estimated experimentally by measuring accelerations. By combining numerical predictions with experimental measurements the location and severity of damage can be identified. This method has been successfully applied to prismatic beam problems. In the present work, the idea is extended to identifying damage in thin plate problems. To identify damage in thin plates by the proposed vibratory power method, the two-dimensional damage index and damage index ratio are newly introduced. The plate is assumed to be of uniform thickness and damaged in the form of a crack simulated as a straight cut of finite length. The vibratory power of the plate is estimated from frequency response functions to random excitations. First, the proposed method is applied numerically and then verified experimentally. Both numerical and experimental results show the present method can identify not only the location of damage but also its direction. The location and direction can be identified by investigating the damage index, the damage index ratio, and local principal axes of the index peak in the vicinity of the damage. The spatial distribution of the damage index, newly introduced in beam problems, can be considered as a scalar field in plate problems. In the neighborhood of the damage, the damage index has the shape of a semi-ellipsoid or a semi-ovoid, and it is found that the major principal axis corresponds to the direction of the crack. It enables us to identify the damage direction correctly without ambiguity.

  11. Preliminary Measurements From A New Flat Plate Facility For Aerodynamic Research

    SciTech Connect

    D. M. McEligot; D. W. Nigg; E. J. Walsh; D. Hernon; M.R.D. Davies

    2005-03-01

    This paper details the design and preliminary measurements used in the characterisation of a new flat plate research facility. The facility is designed specifically to aid in the understanding of entropy generation throughout the boundary layer with special attention given to non-equilibrium flows. Hot-wire measurements were obtained downstream of two turbulence generating grids. The turbulence intensity, integral and dissipation length scale ranges measured are 1.6%-7%, 5mm-17mm and 0.7mm-7mm, respectively. These values compared well to existing correlations. The flow downstream of both grids was found to be homogenous and isotropic. Flow visualisation is employed to determine aerodynamic parameters such as flow 2-dimensionality and the effect of the flap angle on preventing separation at the leading edge. The flow was found to be 2-dimensional over all measurement planes. The non-dimensional pressure distribution of a modern turbine blade suction surface is simulated on the flat plate through the use of a variable upper wall. The Reynolds number range based on wetted plate length and inlet velocity is 70,000-4,000,000.

  12. Validating Machine Learning Algorithms for Twitter Data Against Established Measures of Suicidality

    PubMed Central

    2016-01-01

    Background One of the leading causes of death in the United States (US) is suicide and new methods of assessment are needed to track its risk in real time. Objective Our objective is to validate the use of machine learning algorithms for Twitter data against empirically validated measures of suicidality in the US population. Methods Using a machine learning algorithm, the Twitter feeds of 135 Mechanical Turk (MTurk) participants were compared with validated, self-report measures of suicide risk. Results Our findings show that people who are at high suicidal risk can be easily differentiated from those who are not by machine learning algorithms, which accurately identify the clinically significant suicidal rate in 92% of cases (sensitivity: 53%, specificity: 97%, positive predictive value: 75%, negative predictive value: 93%). Conclusions Machine learning algorithms are efficient in differentiating people who are at a suicidal risk from those who are not. Evidence for suicidality can be measured in nonclinical populations using social media data. PMID:27185366

  13. Transducer-actuator systems and methods for performing on-machine measurements and automatic part alignment

    DOEpatents

    Barkman, William E.; Dow, Thomas A.; Garrard, Kenneth P.; Marston, Zachary

    2016-07-12

    Systems and methods for performing on-machine measurements and automatic part alignment, including: a measurement component operable for determining the position of a part on a machine; and an actuation component operable for adjusting the position of the part by contacting the part with a predetermined force responsive to the determined position of the part. The measurement component consists of a transducer. The actuation component consists of a linear actuator. Optionally, the measurement component and the actuation component consist of a single linear actuator operable for contacting the part with a first lighter force for determining the position of the part and with a second harder force for adjusting the position of the part. The actuation component is utilized in a substantially horizontal configuration and the effects of gravitational drop of the part are accounted for in the force applied and the timing of the contact.

  14. HTS electrical machines with YBCO bulk and Ag-BSCCO plate-shape HTS elements: recent results and future development

    NASA Astrophysics Data System (ADS)

    Kovalev, L. K.; Ilushin, K. V.; Penkin, V. T.; Kovalev, K. L.; Koneev, S. M.-A.; Modestov, K. A.; Larionoff, S. A.; Gawalek, W.; Oswald, B.

    2001-05-01

    Novel types of electric HTS motors with the rotor containing bulk YBCO elements are presented. Different schematics of hysteresis, reluctance “trapped field” and composed HTS motors are discussed. The two-dimensional mathematical models describing the processes in such types of HTS machines were developed on the basis of the theoretical analysis of the electrodynamic and hysteresis processes in the multi-domain and single-domain YBCO ceramic samples. The test results of the series of these HTS motors with output power 1-20 kW and current frequency 50 and 400 Hz are given. These results show that in the media of liquid nitrogen the specific output power per one weight unit is four to five times better then for conventional electric machines. The design of a new high power HTS motor operating in the liquid nitrogen with output power 200 kW (and more) is discussed. Future applications of new types of HTS motors for airspace and on-land industry and transport systems are discussed.

  15. Luminance measurement to evaluate the damage of notched FRP plates in static load

    SciTech Connect

    Hyakutake, H.; Yamamoto, T.

    1995-11-01

    The validity of the damage criterion for notched FRP plates based on the concept of severity near the notch root is subjected to further experimental scrutiny. An experimental program is presented which examines the effect of notch geometry on the damage near the notch root of FRP plates. This is accomplished by obtaining experimental data on the notched specimens of a glass cloth/epoxy laminate for a wide range of notch geometries in tension and bending. The process of initiation and growth of damage near the notch root was measured by means of the luminance measurement technique with a CCD camera. The experiment shows that the growth of damage zone near the notch root was governed predominantly by both the notch-root radius and the maximum elastic stress at the notch root, while it was independent of notch depth and type of loading. On the basis of the concept of severity, the experimental results can be clearly elucidated.

  16. Frequency domain fluorescence lifetime microwell-plate platform for respirometry measurements

    NASA Astrophysics Data System (ADS)

    Chatni, M. R.; Yale, G.; Van Ryckeghem, A.; Porterfield, D. M.

    2010-04-01

    Traditionally micro-well plate based platforms used in biology utilize fluorescence intensity based methods to measure processes of biological relevance. However, fluorescence intensity measurements suffer from calibration drift due to a variety of factors. Photobleaching and self-quenching of the fluorescent dyes cause the intensity signal to drop over the lifetime of sensor immobilized inside the well. Variation in turbidity of the sample during the course of the measurement affects the measured fluorescence intensity. In comparison, fluorescence lifetime measurements are not significantly affected by these factors because fluorescence lifetime is a physico-chemical property of the fluorescent dye. Reliable and inexpensive frequency domain fluorescence lifetime instrumentation platforms are possible because the greater tolerance for optical alignment, and because they can be performed using inexpensive light sources such as LEDs. In this paper we report the development of a frequency domain fluorescence lifetime well-plate platform utilizing an oxygen sensitive transition-metal ligand complex fluorophore with a lifetime in the microsecond range. The fluorescence lifetime dye is incorporated in a polymer matrix and immobilized on the base of micro-well of a 60 well micro-well plate. Respiration measurements are performed in both aqueous and non-aqueous environment. Respirometry measurements were recorded from single Daphnia magna egg in hard water. Daphnia is an aquatic organism, important in environmental toxicology as a standard bioassay and early warning indicator for water quality monitoring. Also respirometry measurements were recorded from Tribolium castaneum eggs, which are common pests in the processed flour industry. These eggs were subjected to mitochondrial electron transport chain inhibitor such as potassium cyanide (KCN) and its effects on egg respiration were measured in real-time.

  17. Modeling and measurement of angle-beam wave propagation in a scatterer-free plate

    NASA Astrophysics Data System (ADS)

    Dawson, Alexander J.; Michaels, Jennifer E.; Michaels, Thomas E.

    2017-02-01

    Wavefield imaging has been shown to be a powerful tool for improving the understanding and characterization of wave propagation and scattering in plates. The complete measurement of surface displacement over a 2-D grid provided by wavefield imaging has the potential to serve as a useful means of validating ultrasonic models. Here, a preliminary study of ultrasonic angle-beam wave propagation in a scatterer-free plate using a combination of wavefield measurements and 2-D finite element models is described. Both wavefield imaging and finite element analysis are used to study the propagation of waves at a refracted angle of 56.8° propagating in a 6.35 mm thick aluminum plate. Wavefield imaging is performed using a laser vibrometer mounted on an XYZ scanning stage, which is programmed to move point-to-point on a rectilinear grid to acquire waveform data. The commercial finite element software package, PZFlex, which is specifically designed to handle large, complex ultrasonic problems, is used to create a 2-D cross-sectional model of the transducer and plate. For model validation, vertical surface displacements from both the wavefield measurements and the PZFlex finite element model are compared and found to be in excellent agreement. The validated PZFlex model is then used to explain the mechanism of Rayleigh wave generation by the angle-beam wedge. Since the wavefield measurements are restricted to the specimen surface, the cross-sectional PZFlex model is able to provide insights the wavefield data cannot. This study illustrates how information obtained from ultrasonic experiments and modeling results can be combined to improve understanding of angle-beam wave generation and propagation.

  18. Size and concentration measurements of particles produced in commercial chromium plating processes

    SciTech Connect

    Bonin, M.P.; Flower, W.L.; Renzi, R.F.; Peng, L.W.

    1995-11-01

    Optical measurements of particle size and concentration were made at the chromium plating tank and exhaust system at a commercial hexavalent chromium plating facility. Particles were examined at three locations in the exhaust system: (1) directly at the hexavalent chromium plating bath surface, (2) at the exit of a cyclone separator located in the exhaust system approximately three to four meters downstream of the bath, and (3) in the exhaust stack, downstream of the induced draft fan and all abatement devices. Particle diameters at the bath surface ranged from 0.3 to 25 {mu}m. Downstream of the cyclone exit and mesh pad filters, particle top sizes were approximately 5 and 0.7 mm, respectively. On a mass basis, the collection efficiency of all abatement devices was 99.997%. Assuming that droplets in the flow consist primarily of water and chromium, correcting the total particle mass flow against water content gives a chromium emission rate of 64,000 {mu}g/hr, which compares favorably with a value of 77,000 {mu}g/hr measured with EPA methods. This initial agreement, which should be validated through additional measurements over a broad range of flow conditions, raises the possibility of continuous monitoring for chromium metal emissions using particle size/mass as a surrogate. 6 refs., 7 figs.

  19. Measurement-induced operation of two-ion quantum heat machines

    NASA Astrophysics Data System (ADS)

    Chand, Suman; Biswas, Asoka

    2017-03-01

    We show how one can implement a quantum heat machine by using two interacting trapped ions, in presence of a thermal bath. The electronic states of the ions act like a working substance, while the vibrational mode is modelled as the cold bath. The heat exchange with the cold bath is mimicked by the projective measurement of the electronic states. We show how such measurement in a suitable basis can lead to either a quantum heat engine or a refrigerator, which undergoes a quantum Otto cycle. The local magnetic field is adiabatically changed during the heat cycle. The performance of the heat machine depends upon the interaction strength between the ions, the magnetic fields, and the measurement cost. In our model, the coupling to the hot and the cold baths is never switched off in an alternative fashion during the heat cycle, unlike other existing proposals of quantum heat engines. This makes our proposal experimentally realizable using current tapped-ion technology.

  20. A passive guard for low thermal conductivity measurement of small samples by the hot plate method

    NASA Astrophysics Data System (ADS)

    Jannot, Yves; Degiovanni, Alain; Grigorova-Moutiers, Veneta; Godefroy, Justine

    2017-01-01

    Hot plate methods under steady state conditions are based on a 1D model to estimate the thermal conductivity, using measurements of the temperatures T 0 and T 1 of the two sides of the sample and of the heat flux crossing it. To be consistent with the hypothesis of the 1D heat flux, either a hot plate guarded apparatus is used, or the temperature is measured at the centre of the sample. On one hand the latter method can be used only if the ratio thickness/width of the sample is sufficiently low and on the other hand the guarded hot plate method requires large width samples (typical cross section of 0.6  ×  0.6 m2). That is why both methods cannot be used for low width samples. The method presented in this paper is based on an optimal choice of the temperatures T 0 and T 1 compared to the ambient temperature T a, enabling the estimation of the thermal conductivity with a centered hot plate method, by applying the 1D heat flux model. It will be shown that these optimal values do not depend on the size or on the thermal conductivity of samples (in the range 0.015-0.2 W m-1 K-1), but only on T a. The experimental results obtained validate the method for several reference samples for values of the ratio thickness/width up to 0.3, thus enabling the measurement of the thermal conductivity of samples having a small cross-section, down to 0.045  ×  0.045 m2.

  1. Identification of thin elastic isotropic plate parameters applying Guided Wave Measurement and Artificial Neural Networks

    NASA Astrophysics Data System (ADS)

    Pabisek, Ewa; Waszczyszyn, Zenon

    2015-12-01

    A new hybrid computational system for material identification (HCSMI) is presented, developed for the identification of homogeneous, elastic, isotropic plate parameters. Attention is focused on the construction of dispersion curves, related to Lamb waves. The main idea of the system HCSMI lies in separation of two essential basic computational stages, corresponding to direct or inverse analyses. In the frame of the first stage an experimental dispersion curve DCexp is constructed, applying Guided Wave Measurement (GWM) technique. Then, in the other stage, corresponding to the inverse analysis, an Artificial Neural Network (ANN) is trained 'off line'. The substitution of results of the first stage, treated as inputs of the ANN, gives the values of identified plate parameters. In such a way no iteration is needed, unlike to the classical approach. In such an approach, the "distance" between the approximate experimental curves DCexp and dispersion curves DCnum obtained in the direct analysis, is iteratively minimized. Two case studies are presented, corresponding either to measurements in laboratory tests or those related to pseudo-experimental noisy data of computer simulations. The obtained results prove high numerical efficiency of HCSMI, applied to the identification of aluminum plate parameters.

  2. A method for measuring skin friction drag on a flat plate in contaminated gas flows

    NASA Technical Reports Server (NTRS)

    Oetting, R. B.; Patterson, G. K.

    1984-01-01

    A technique for measuring friction drag in turbulent gas and gas/particle flows over flat plates is presented, and preliminary results are reported. A 0.25-in.-thick 72 x 6-in. Al plate is suspended by six horizontal support air bearings and four vertical alignment air bearings between fixed dummy plates and leading-edge and trailing-edge fairings in the 32-in.-high 48-in.-wide 11-ft-long test section of a closed-circuit atmospheric wind tunnel operating at 50-150 ft/sec. Particles of Fe and Al oxides of diameter 20-150 microns and density up to 0.3 lb particles per lb air are injected via a 6 x 0.167-in. nozzle; turbulence is induced by a roughened section of the leading-edge fairing; and friction drag is measured using a load-cell pressure transducer. Sample results are shown in a graph, demonstrating good agreement with theoretical drag calculations.

  3. The Muenster Redshift Project - Automated redshift measurements from low-dispersion objective prism Schmidt plates

    NASA Astrophysics Data System (ADS)

    Schuecker, Peter

    A three-dimensional galaxy survey at faint magnitudes and over large volumes of space was carried out as part of the Muenster Redshift Project. Three different methods were used to enhance the reliability of the redshifts measured from objective prison plates: the correlation method, the least-squares method, and the break method where continuous breaks are identified directly. The redshift errors of the individual methods turn out to be 0.007 (correlation), 0.011 (direct identification), and 0.016 (least squares). Using the method described in the paper, it is possible to obtain about 6000 galaxy redshifts from one objective prism plate at high galactic latitudes for objects with m(J) less than 20.

  4. X-ray, K-edge measurement of uranium concentration in reactor fuel plates

    SciTech Connect

    Jensen, T.; Aljundi, T.; Whitmore, C.; Zhong, H.; Gray, J.N.

    1997-11-26

    Under the Characterization, Monitoring, and Sensor Technology Crosscutting Program, the authors have designed and built a K-edge heavy-metal detector that measures the level of heavy-metal content inside closed containers in a nondestructive, non-invasive way. They have applied this technique to measurement of the amount of uranium in stacks of reactor fuel plates containing nuclear materials of different enrichments and alloys. They have obtained good agreement with expected uranium concentrations ranging from 60 mg/cm{sup 2} to 3,000 mg/cm{sup 2}, and have demonstrated that the instrument can operate in a high radiation field (> 200 mR/hr).

  5. Quasi-continuous combined scattered light and fluorescence measurements: a novel measurement technique for shaken microtiter plates.

    PubMed

    Samorski, M; Müller-Newen, G; Büchs, J

    2005-10-05

    A novel quasi-continuous on-line measuring technique for shaken microtiter plates is presented. Light scattering as well as intracellular and/or protein fluorescence (e.g. NADH, YFP) is measured during the shaking procedure, thus allowing a process monitoring of 96 different simultaneous cultures in a microtiter plate. In contrast to existing measurement techniques, the shaking process does not have to be stopped to take the measurements, thus avoiding the corresponding interruption of the cultures' oxygen supply and any unpredictable effects on the cultures. Experiments were conducted with E. coli in LB, TB, and MOPS minimal medium and V. natriegens in modified LB and TB media. Intensity curves of scattered light and NADH fluorescence were used to distinguish different lag phases, growth velocities, or inoculation densities. Data from this new method corresponded well to the off-line measured optical densities and to the oxygen transfer rates of cultures run in simultaneously conducted shake flask experiments at equivalent oxygen transfer capacities. With the aid of yellow fluorescence protein fused to interleukin-6 the optimal induction time of an expressing E. coli strain could be determined by on-line monitoring of product formation. Thus, this measuring technique enables the researcher to evaluate and to discriminate different cultures on a screening level and to improve screening conditions, process development and scale-up.

  6. Photometric calibration of NGS/POSS and ESO/SRC plates using the NOAO PDS measuring engine. I - Stellar photometry

    NASA Technical Reports Server (NTRS)

    Cutri, Roc M.; Low, Frank J.; Marvel, Kevin B.

    1992-01-01

    The PDS/Monet measuring engine at the National Optical Astronomy Observatory was used to obtain photometry of nearly 10,000 stars on the NGS/POSS and 2000 stars on the ESO/SRC Survey glass plates. These measurements have been used to show that global transformation functions exist that allow calibration of stellar photometry from any blue or red plate to equivalent Johnson B and Cousins R photoelectric magnitudes. The four transformation functions appropriate for the POSS O and E and ESO/SRC J and R plates were characterized, and it was found that, within the measurement uncertainties, they vary from plate to plate only by photometric zero-point offsets. A method is described to correct for the zero-point shifts and to obtain calibrated B and R photometry of stellar sources to an average accuracy of 0.3-0.4 mag within the range R between values of 8 and 19.5 for red plates in both surveys, B between values of 9 and 20.5 on POSS blue plates, and B between values of 10 and 20.5 on ESO/SRC blue plates. This calibration procedure makes it possible to obtain rapid photometry of very large numbers of stellar sources.

  7. The thermal state of the Arabian plate derived from heat flow measurements in Oman and Yemen

    NASA Astrophysics Data System (ADS)

    Rolandone, Frederique; Lucazeau, Francis; Leroy, Sylvie; Mareschal, Jean-Claude; Jorand, Rachel; Goutorbe, Bruno; Bouquerel, Hélène

    2013-04-01

    The dynamics of the Afar plume and the rifting of the Red Sea and the Gulf of Aden affect the present-day thermal regime of the Arabian plate. However, the Arabian plate is a Precambrian shield covered on its eastern part by a Phanerozoic platform and its thermal regime, before the plume and rifting activities, should be similar to that of other Precambrian shields with a thick and stable lithosphere. The first heat flow measurements in the shield, in Saudi Arabia, yielded low values (35-44 mW/m2), similar to the typical shields values. Recent heat flow measurements in Jordan indicate higher values (56-66 mW/m2). As part of the YOCMAL project (YOung Conjugate MArgins Laboratory), we have conducted heat flow measurements in southern and northern Oman to obtain 10 new heat flux values in the eastern Arabian plate. We also derived 20 heat flux values in Yemen and Oman by processing thermal data from oil exploration wells. The surface heat flux in these different locations is uniformly low (45 mW/m2). The heat production in samples from the Dhofar and Socotra Precambrian basement is also low (0.7 µW/m3). Differences in heat flow between the eastern (60 mW/m2) and the western (45 mW/m2) parts of Arabia reflect differences in crustal heat production as well as a higher mantle heat flux in the west. We have calculated a steady state geotherm for the Arabian platform that intersects the isentropic temperature profile at a depth of about 150 km, consistent with the seismic observations. Seismic tomography studies of the mantle beneath Arabia also show this east-west contrast. Seismic studies have shown that the lithosphere is rather thin, 100 km or less below the shield and 150 km below the platform. The lithospheric thickness for the Arabian plate is 150 km, and the progressive thinning near the Red Sea, caused by the thermal erosion of the plume material, is too recent to be detected at the surface. The Afar plume mostly affects the base of the Arabian lithosphere along

  8. Leaf wetness duration measurement: comparison of cylindrical and flat plate sensors under different field conditions.

    PubMed

    Sentelhas, Paulo C; Gillespie, Terry J; Santos, Eduardo A

    2007-03-01

    In general, leaf wetness duration (LWD) is a key parameter influencing plant disease epidemiology, since it provides the free water required by pathogens to infect foliar tissue. LWD is used as an input in many disease warning systems, which help growers to decide the best time to spray their crops against diseases. Since there is no observation standard either for sensor or exposure, LWD measurement is often problematic. To assess the performance of electronic sensors, LWD measurements obtained with painted cylindrical and flat plate sensors were compared under different field conditions in Elora, Ontario, Canada, and in Piracicaba, São Paulo, Brazil. The sensors were tested in four different crop environments--mowed turfgrass, maize, soybean, and tomatoes--during the summer of 2003 and 2004 in Elora and during the winter of 2005 in Piracicaba. Flat plate sensors were deployed facing north and at 45 degrees to horizontal, and cylindrical sensors were deployed horizontally. At the turfgrass site, both sensors were installed 30 cm above the ground, while at the crop fields, the sensors were installed at the top and inside the canopy (except for maize, with a sensor only at the top). Considering the flat plate sensor as a reference (Sentelhas et al. Operational exposure of leaf wetness sensors. Agric For Meteorol 126:59-72, 2004a), the results in the more humid climate at Elora showed that the cylindrical sensor overestimated LWD by 1.1-4.2 h, depending on the crop and canopy position. The main cause of the overestimation was the accumulation of big water drops along the bottom of the cylindrical sensors, which required much more energy and, consequently, time to evaporate. The overall difference between sensors when evaporating wetness formed during the night was around 1.6 h. Cylindrical sensors also detected wetness earlier than did flat plates--around 0.6 h. Agreement between plate and cylinder sensors was much better in the drier climate at Piracicaba. These

  9. Information Contents of a Signal at Repeated Positioning Measurements of the Coordinate Measuring Machine (CMM) by Laser Interferometer

    NASA Astrophysics Data System (ADS)

    Stejskal, Tomáš; Kelemenová, Tatiana; Dovica, Miroslav; Demeč, Peter; Štofa, Miroslav

    2016-10-01

    The input of this paper lies in displaying possibilities how to determine the condition of a coordinate measuring machine (CMM) based on a large number of repeated measurements. The number of repeated measurements exceeds common requirements for determining positioning accuracy. The total offset in the accuracy of spatial positioning consists of partial inaccuracies of individual axes. 6 basic errors may be defined at each axis. In a triaxial set, that translates into 18 errors, to which an offset from the perpendicularity between the axial pairs must be added. Therefore, the combined number of errors in a single position is 21. These errors are systemic and stem from the machine's geometry. In addition, there are accidental errors to account for as well. Accidental errors can be attributed to vibrations, mass inertness, passive resistance, and in part to fluctuations in temperature. A peculiar set of systemic errors are time-varying errors. The nature of those errors may be reversible, for instance if they result from influence of temperature or elastic deformation. They can be also irreversible, for example as a result of wear and tear or line clogging, due to loosened connection or permanent deformation of a part post collision. A demonstration of thermal equalizing of the machine's parts may also be observed in case of failure to adhere to a sufficient time interval from the moment the air-conditioning is turned on. Repeated measurements done on a selected axis with linear interferometer can provide complex information on the CMM condition and also on the machine's interaction with the given technical environment.

  10. Focal length measurement based on Fresnel diffraction from a phase plate.

    PubMed

    Dashtdar, Masoomeh; Mohammad-Ali Hosseini-Saber, S

    2016-09-10

    A method based on the Fresnel diffraction of light from the phase step is introduced for measuring effective focal length (EFL) and back focal length (BFL) of optical imaging systems. It is shown that, as a transparent plane-parallel plate is illuminated at a boundary region by a monochromatic beam of light, Fresnel diffraction occurs because of the abrupt change in phase imposed by the finite change in refractive index at the plate boundary. Variation of the incident angle in a convergent (or divergent) beam of light causes the periodic intensity along the central fringe of the diffraction pattern. The measurement of the extrema position of the intensity distribution accurately provides the EFL and BFL. The technique is easy to apply and can measure a wide range of both positive and negative focal lengths. The measuring setup can be very compact with low mechanical and optical noises. As examples of this technique, the EFLs of five different lenses are experimentally obtained. The results are quite consistent with the values indicated by the lens manufacturer.

  11. A technique using a stellar spectrographic plate to measure terrestrial ozone column depth

    SciTech Connect

    Wong, Alec Y.

    1995-08-01

    This thesis examines the feasibility of a technique to extract ozone column depths from photographic stellar spectra in the 5000--7000 Angstrom spectral region. A stellar spectrographic plate is measured to yield the relative intensity distribution of a star`s radiation after transmission through the earth`s atmosphere. The amount of stellar radiation absorbed by the ozone Chappuis band is proportional to the ozone column depth. The measured column depth is within 10% the mean monthly value for latitude 36{degree}N, however the uncertainty is too large to make the measurement useful. This thesis shows that a 10% improvement to the photographic sensitivity uncertainty can decrease the column depth uncertainty to a level acceptable for climatic study use. This technique offers the possibility of measuring past ozone column depths.

  12. Combination of a vision system and a coordinate measuring machine for rapid coordinate metrology

    NASA Astrophysics Data System (ADS)

    Qu, Yufu; Pu, Zhaobang; Liu, Guodong

    2002-09-01

    This paper presents a novel methodology that integrates a vision system and a coordinate measuring machine for rapid coordinate metrology. Rapid acquisition of coordinate data from parts having tiny dimension, complex geometry and soft or fragile material has many applications. Typical examples include Large Scale Integrated circuit, glass or plastic part measurement, and reverse engineering in rapid product design and realization. In this paper, a novel approach to a measuring methodology for a vision integrated coordinate measuring system is developed and demonstrated. The vision coordinate measuring system is characterized by an integrated use of a high precision coordinate measuring machine (CMM), a vision system, advanced computational software, and the associated electronics. The vision system includes a charge-coupled device (CCD) camera, a self-adapt brightness power, and a graphics workstation with an image processing board. The vision system along with intelligent feature recognition and auto-focus algorithms provides the feature point space coordinate of global part profile after the system has been calibrated. The measured data may be fitted to geometry element of part profile. The obtained results are subsequently used to compute parameters consist of curvature radius, distance, shape error and surface reconstruction. By integrating the vision system with the CMM, a highly automated, high speed, 3D coordinate acquisition system is developed. It has potential applications in a whole spectrum of manufacturing problems with a major impact on metrology, inspection, and reverse engineering.

  13. On-machine sensors to measure paper mechanical properties. Final report

    SciTech Connect

    Hall, M.S.; Brodeur, P.H.; Jackson, T.G.

    1993-10-01

    The measurement of the velocity of ultrasound provides a nondestructive means to characterize the elastic stiffness properties of paper. The objective of this project is to develop sensors capable of measuring the velocity of ultrasound in the thickness and in-plane directions of moving paper webs. On-machine measurements would allow continuous monitoring of product quality as well as provide data for controlling the papermaking process. This final report first reviews the background and various technical approaches explored. Then the preferred configurations and examples of measurements on moving paper webs in the laboratory are presented and discussed. The report concludes with a summary of project results and recommendations for further developments. Transducers mounted in fluid-filled wheels are used to make thickness direction, ZD, ultrasound velocity measurements on paper webs moving in the nip between two such wheels. Comparisons of the arrival times of echo and transmitted pulses with and without the paper web in the nip provide a measure of the transit time and caliper. Bimorph transducers mounted in an aluminum cylinder are used for machine direction (MD) and cross direction (CD) in-plane measurements. These ZD and in-plane sensors are mounted on a web handler in the IPST laboratory.

  14. Plate convergence measured by GPS across the Sundaland/Philippine Sea Plate deformed boundary: the Philippines and eastern Indonesia

    NASA Astrophysics Data System (ADS)

    Rangin, C.; Le Pichon, X.; Mazzotti, S.; Pubellier, M.; Chamot-Rooke, N.; Aurelio, M.; Walpersdorf, Andrea; Quebral, R.

    1999-11-01

    The western boundary of the Philippine Sea (PH) Plate in the Philippines and eastern Indonesia corresponds to a wide deformation zone that includes the stretched continental margin of Sundaland, the Philippine Mobile Belt (PMB), extending from Luzon to the Molucca Sea, and a mosaic of continental blocks around the PH/Australia/Sunda triple junction. The GPS GEODYSSEA data are used to decipher the present kinematics of this complex area. In the Philippines, the overall scheme is quite simple: two opposing rotations on either side of the left-lateral Philippine Fault, clockwise to the southwest and counterclockwise to the northeast, transfer 55 per cent of the PH/Sundaland convergence from the Manila Trench to the northwest to the Philippine Trench to the southeast. Further south, 80 per cent of the PH/Sunda convergence is absorbed in the double subduction system of the Molucca Sea and less than 20 per cent along both continental margins of northern Borneo. Finally, within the triple junction area between the Sundaland, PH and Australia plates, from Sulawesi to Irian Jaya, preferential subduction of the Celebes Sea induces clockwise rotation of the Sulu block, which is escaping toward the diminishing Celebes Sea oceanic space from the eastward-advancing PH Plate. To the south, we identify an undeformed Banda block that rotates counterclockwise with respect to Australia and clockwise with respect to Sundaland. The kinematics of this block can be defined and enable us to compute the rates of southward subduction of the Banda block within the Flores Trench and of eastward convergence of the Makassar Straits with the Banda block. The analysis made in this paper confirms that this deformation is compatible with the eastward motion of Sundaland with respect to Eurasia determined by the GEODYSSEA programme but is not compatible with the assumption that Sundaland belongs to Eurasia, as was often assumed prior to this study.

  15. Enhancement of measurement sensitivity in the formation of shear interferograms of transparent plates with small residual wedging

    SciTech Connect

    But', A I; Lyalikov, A M

    2011-10-31

    We have proposed a method for increasing the sensitivity of measurements of the wedge angle in transparent plates. The method is based on formation of the holographic shear interferograms using a combination of 180 Degree-Sign rotation of the plate with byturn adjustment of interferograms in its images to an infinitely wide fringe. The sensitivity enhancement is due to the increased number of interference fringes in the observed images of the wedged plate, which favours the reduction of the measurement error during optical processing of the obtained interferograms. Data on the experimental validation of the proposed method are presented.

  16. Structure Model Index Does Not Measure Rods and Plates in Trabecular Bone

    PubMed Central

    Salmon, Phil L.; Ohlsson, Claes; Shefelbine, Sandra J.; Doube, Michael

    2015-01-01

    Structure model index (SMI) is widely used to measure rods and plates in trabecular bone. It exploits the change in surface curvature that occurs as a structure varies from spherical (SMI = 4), to cylindrical (SMI = 3) to planar (SMI = 0). The most important assumption underlying SMI is that the entire bone surface is convex and that the curvature differential is positive at all points on the surface. The intricate connections within the trabecular continuum suggest that a high proportion of the surface could be concave, violating the assumption of convexity and producing regions of negative differential. We implemented SMI in the BoneJ plugin and included the ability to measure the amounts of surface that increased or decreased in area after surface mesh dilation, and the ability to visualize concave and convex regions. We measured SMI and its positive (SMI+) and negative (SMI−) components, bone volume fraction (BV/TV), the fraction of the surface that is concave (CF), and mean ellipsoid factor (EF) in trabecular bone using 38 X-ray microtomography (XMT) images from a rat ovariectomy model of sex steroid rescue of bone loss, and 169 XMT images from a broad selection of 87 species’ femora (mammals, birds, and a crocodile). We simulated bone resorption by eroding an image of elephant trabeculae and recording SMI and BV/TV at each erosion step. Up to 70%, and rarely <20%, of the trabecular surface is concave (CF 0.155–0.700). SMI is unavoidably influenced by aberrations induced by SMI−, which is strongly correlated with BV/TV and CF. The plate-to-rod transition in bone loss is an erroneous observation resulting from the close and artifactual relationship between SMI and BV/TV. SMI cannot discern between the distinctive trabecular geometries typical of mammalian and avian bone, whereas EF clearly detects birds’ more plate-like trabeculae. EF is free from confounding relationships with BV/TV and CF. SMI results reported in the literature should be

  17. X-ray power and yield measurements at the refurbished Z machine

    SciTech Connect

    Jones, M. C.; Ampleford, D. J.; Cuneo, M. E.; Hohlfelder, R.; Jennings, C. A.; Johnson, D. W.; Jones, B.; Lopez, M. R.; MacArthur, J.; Mills, J. A.; Preston, T.; Rochau, G. A.; Savage, M.; Spencer, D.; Sinars, D. B.; Porter, J. L.

    2014-08-04

    Advancements have been made in the diagnostic techniques to measure accurately the total radiated x-ray yield and power from z-pinch loads at the Z Machine with high accuracy. The Z-accelerator is capable of outputting 2MJ and 330 TW of x-ray yield and power, and accurately measuring these quantities is imperative. We will describe work over the past several years which include the development of new diagnostics, improvements to existing diagnostics, and implementation of automated data analysis routines. A set of experiments were conducted on the Z machine where the load and machine configuration were held constant. During this shot series, it was observed that total z-pinch x-ray emission power determined from the two common techniques for inferring the x-ray power, Kimfol filtered x-ray diode diagnostic and the Total Power and Energy diagnostic gave 450 TW and 327 TW respectively. Our analysis shows the latter to be the more accurate interpretation. More broadly, the comparison demonstrates the necessity to consider spectral response and field of view when inferring xray powers from z-pinch sources.

  18. Design and Analysis of a Sensor System for Cutting Force Measurement in Machining Processes.

    PubMed

    Liang, Qiaokang; Zhang, Dan; Coppola, Gianmarc; Mao, Jianxu; Sun, Wei; Wang, Yaonan; Ge, Yunjian

    2016-01-07

    Multi-component force sensors have infiltrated a wide variety of automation products since the 1970s. However, one seldom finds full-component sensor systems available in the market for cutting force measurement in machine processes. In this paper, a new six-component sensor system with a compact monolithic elastic element (EE) is designed and developed to detect the tangential cutting forces Fx, Fy and Fz (i.e., forces along x-, y-, and z-axis) as well as the cutting moments Mx, My and Mz (i.e., moments about x-, y-, and z-axis) simultaneously. Optimal structural parameters of the EE are carefully designed via simulation-driven optimization. Moreover, a prototype sensor system is fabricated, which is applied to a 5-axis parallel kinematic machining center. Calibration experimental results demonstrate that the system is capable of measuring cutting forces and moments with good linearity while minimizing coupling error. Both the Finite Element Analysis (FEA) and calibration experimental studies validate the high performance of the proposed sensor system that is expected to be adopted into machining processes.

  19. X-ray power and yield measurements at the refurbished Z machine

    DOE PAGES

    Jones, M. C.; Ampleford, D. J.; Cuneo, M. E.; ...

    2014-08-04

    Advancements have been made in the diagnostic techniques to measure accurately the total radiated x-ray yield and power from z-pinch loads at the Z Machine with high accuracy. The Z-accelerator is capable of outputting 2MJ and 330 TW of x-ray yield and power, and accurately measuring these quantities is imperative. We will describe work over the past several years which include the development of new diagnostics, improvements to existing diagnostics, and implementation of automated data analysis routines. A set of experiments were conducted on the Z machine where the load and machine configuration were held constant. During this shot series,more » it was observed that total z-pinch x-ray emission power determined from the two common techniques for inferring the x-ray power, Kimfol filtered x-ray diode diagnostic and the Total Power and Energy diagnostic gave 450 TW and 327 TW respectively. Our analysis shows the latter to be the more accurate interpretation. More broadly, the comparison demonstrates the necessity to consider spectral response and field of view when inferring xray powers from z-pinch sources.« less

  20. Design and Analysis of a Sensor System for Cutting Force Measurement in Machining Processes

    PubMed Central

    Liang, Qiaokang; Zhang, Dan; Coppola, Gianmarc; Mao, Jianxu; Sun, Wei; Wang, Yaonan; Ge, Yunjian

    2016-01-01

    Multi-component force sensors have infiltrated a wide variety of automation products since the 1970s. However, one seldom finds full-component sensor systems available in the market for cutting force measurement in machine processes. In this paper, a new six-component sensor system with a compact monolithic elastic element (EE) is designed and developed to detect the tangential cutting forces Fx, Fy and Fz (i.e., forces along x-, y-, and z-axis) as well as the cutting moments Mx, My and Mz (i.e., moments about x-, y-, and z-axis) simultaneously. Optimal structural parameters of the EE are carefully designed via simulation-driven optimization. Moreover, a prototype sensor system is fabricated, which is applied to a 5-axis parallel kinematic machining center. Calibration experimental results demonstrate that the system is capable of measuring cutting forces and moments with good linearity while minimizing coupling error. Both the Finite Element Analysis (FEA) and calibration experimental studies validate the high performance of the proposed sensor system that is expected to be adopted into machining processes. PMID:26751451

  1. Gap Measurement of Point Machine Using Adaptive Wavelet Threshold and Mathematical Morphology

    PubMed Central

    Xu, Tianhua; Wang, Guang; Wang, Haifeng; Yuan, Tangming; Zhong, Zhiwang

    2016-01-01

    A point machine’s gap is an important indication of its healthy status. An edge detection algorithm is proposed to measure and calculate a point machine’s gap from the gap image captured by CCD plane arrays. This algorithm integrates adaptive wavelet-based image denoising, locally adaptive image binarization, and mathematical morphology technologies. The adaptive wavelet-based image denoising obtains not only an optimal denoising threshold, but also unblurred edges. Locally adaptive image binarization has the advantage of overcoming the local intensity variation in gap images. Mathematical morphology may suppress speckle spots caused by reflective metal surfaces in point machines. The subjective and objective evaluations of the proposed method are presented by using point machine gap images from a railway corporation in China. The performance between the proposed method and conventional edge detection methods has also been compared, and the result shows that the former outperforms the latter. PMID:27898042

  2. The Deflection Plate Analyzer: A Technique for Space Plasma Measurements Under Highly Disturbed Conditions

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth H., Jr.; Dutton, Ken; Martinez, Nelson; Smith, Dennis; Stone, Nobie H.

    2004-01-01

    A technique has been developed to measure the characteristics of space plasmas under highly disturbed conditions; e.g., non-Maxwellian plasmas with strong drifting populations and plasmas contaminated by spacecraft outgassing. The present method is an extension of the capabilities of the Differential Ion Flux Probe (DIFP) to include a mass measurement that does not include either high voltage or contamination sensitive devices such as channeltron electron multipliers or microchannel plates. This reduces the complexity and expense of instrument fabrication, testing, and integration of flight hardware as compared to classical mass analyzers. The new instrument design is called the Deflection Plate Analyzer (DPA) and can deconvolve multiple ion streams and analyze each stream for ion flux intensity (density), velocity (including direction of motion), mass, and temperature (or energy distribution). The basic functionality of the DPA is discussed. The performance characteristics of a flight instrument as built for an electrodynamic tether mission, the Propulsive Small Expendable Deployer System (ProSEDS), and the instrument s role in measuring key experimental conditions are also discussed.

  3. Integrated calibration sphere and calibration step fixture for improved coordinate measurement machine calibration

    DOEpatents

    Clifford, Harry J [Los Alamos, NM

    2011-03-22

    A method and apparatus for mounting a calibration sphere to a calibration fixture for Coordinate Measurement Machine (CMM) calibration and qualification is described, decreasing the time required for such qualification, thus allowing the CMM to be used more productively. A number of embodiments are disclosed that allow for new and retrofit manufacture to perform as integrated calibration sphere and calibration fixture devices. This invention renders unnecessary the removal of a calibration sphere prior to CMM measurement of calibration features on calibration fixtures, thereby greatly reducing the time spent qualifying a CMM.

  4. A New Apparatus for Measuring the Temperature at Machine Parts Rotating at High Speeds

    NASA Technical Reports Server (NTRS)

    Gnam, E.

    1945-01-01

    After a brief survey of the available methods for measuring the temperatures of machine parts at high speed, in particular turbine blades and rotors, an apparatus is described which is constructed on the principle of induction. Transmission of the measuring current by sliding contacts therefore is avoided. Up-to-date experiments show that it is possible to give the apparatus a high degree of sensitivity and accuracy. In comparison with sliding contact types, the present apparatus shows the important advantage that it operates for any length of time without wear, and that the contact difficulties, particularly occurring at high sliding speeds,are avoided.

  5. Cavitation on a semicircular leading-edge plate and NACA0015 hydrofoil: Visualization and velocity measurement

    NASA Astrophysics Data System (ADS)

    Kravtsova, A. Yu.; Markovich, D. M.; Pervunin, K. S.; Timoshevskii, M. V.; Hanjalić, K.

    2014-12-01

    Using high-speed visualization and particle image velocimetry (PIV), cavitating flows near a plane plate with a rounded leading edge and NACA0015 hydrofoil at angles of attack from 0° to 9° are studied. In the experiments, several known types of cavitation, as well as some differences, were detected with variation of the cavitation number. In particular, at small angles of attack (up to 3°), cavitation on the plate appears in the form of a streak array; on the hydrofoil, it appears in the form of individual bubbles. For the NACA0015 hydrofoil, isolated and intermittent streaks are divided and grow in regimes with developed cavitation; then, however, they merge in bubble clouds and form an extremely regular cellular structure. With an increase in the angle of attack to 9°, the structure of the cavitation cavity on the hydrofoil is changed by the streak structure, like in the case with the plate. In this work, it is shown that PIV permits one to measure the velocity in cavitating flows, in particular, within the gas-vapor phase. It was established from the analysis of distributions of the average flow velocity and moments of velocity fluctuations that the cavitation generation is caused by the development of the carrier fluid flow near the leading edge of the hydrofoil. Down the stream, however, the flow structure strongly depends on the cavitation regime, which is seen from the comparison of the distributions with the case of a single-phase flow. The presented measurements qualitatively verify general trends and show some quantitative distinctions for the two considered flowpast bodies.

  6. Neutron Diffraction Residual Strain Tensor Measurements Within The Phase IA Weld Mock-up Plate P-5

    SciTech Connect

    Hubbard, Camden R

    2011-09-01

    Oak Ridge National Laboratory (ORNL) has worked with NRC and EPRI to apply neutron and X-ray diffraction methods to characterize the residual stresses in a number of dissimilar metal weld mockups and samples. The design of the Phase IA specimens aimed to enable stress measurements by several methods and computational modeling of the weld residual stresses. The partial groove in the 304L stainless steel plate was filled with weld beads of Alloy 82. A summary of the weld conditions for each plate is provided in Table 1. The plates were constrained along the long edges during and after welding by bolts with spring-loaded washers attached to the 1-inch thick Al backing plate. The purpose was to avoid stress relief due to bending of the welded stainless steel plate. The neutron diffraction method was one of the methods selected by EPRI for non-destructive through thickness strain and stress measurement. Four different plates (P-3 to P-6) were studied by neutron diffraction strain mapping, representing four different welding conditions. Through thickness neutron diffraction strain mappings at NRSF2 for the four plates and associated strain-free d-zero specimens involved measurement along seven lines across the weld and at six to seven depths. The mountings of each plate for neutron diffraction measurements were such that the diffraction vector was parallel to each of the three primary orthogonal directions of the plate: two in-plane directions, longitudinal and transverse, and the direction normal to the plate (shown in left figure within Table 1). From the three orthogonal strains for each location, the residual stresses along the three plate directions were calculated. The principal axes of the strain and stress tensors, however, need not necessarily align with the plate coordinate system. To explore this, plate P-5 was selected for examination of the possibility that the principal axes of strain are not along the sample coordinate system axes. If adequate data could

  7. In situ measured growth rates of bainite plates in an Fe-C-Mn-Si superbainitic steel

    NASA Astrophysics Data System (ADS)

    Hu, Zhang-wei; Xu, Guang; Hu, Hai-jiang; Wang, Li; Xue, Zheng-liang

    2014-04-01

    The growth rates of bainite plates in an Fe-C-Mn-Si superbainitic steel were investigated by in situ observation. The lengthening rates of ferrite bainite during both cooling and isothermal holding processes were observed and the growth rates of bainite plates nucleating at grain boundaries, within grains and on preformed bainite were measured. It is indicated that the lengthening rates of bainite plates during the cooling and isothermal processes were different, and that the growth rates of bainite plates nucleating at different types of sites also demonstrated diversity. The bainite plates initiating at grain boundaries during cooling grew the fastest, while the plates nucleating on preformed bainite did the slowest. However, the growth rate of the bainite plates nucleating at grain boundaries during isothermal transformation decreased the most, whereas the bainite plates initiating within grains grew the fastest. In addition, the growth rate of ferrite bainite in the study supported the diffusion transformation mechanism of bainite from the viewpoint of growth rate.

  8. Gene selection and classification for cancer microarray data based on machine learning and similarity measures

    PubMed Central

    2011-01-01

    Background Microarray data have a high dimension of variables and a small sample size. In microarray data analyses, two important issues are how to choose genes, which provide reliable and good prediction for disease status, and how to determine the final gene set that is best for classification. Associations among genetic markers mean one can exploit information redundancy to potentially reduce classification cost in terms of time and money. Results To deal with redundant information and improve classification, we propose a gene selection method, Recursive Feature Addition, which combines supervised learning and statistical similarity measures. To determine the final optimal gene set for prediction and classification, we propose an algorithm, Lagging Prediction Peephole Optimization. By using six benchmark microarray gene expression data sets, we compared Recursive Feature Addition with recently developed gene selection methods: Support Vector Machine Recursive Feature Elimination, Leave-One-Out Calculation Sequential Forward Selection and several others. Conclusions On average, with the use of popular learning machines including Nearest Mean Scaled Classifier, Support Vector Machine, Naive Bayes Classifier and Random Forest, Recursive Feature Addition outperformed other methods. Our studies also showed that Lagging Prediction Peephole Optimization is superior to random strategy; Recursive Feature Addition with Lagging Prediction Peephole Optimization obtained better testing accuracies than the gene selection method varSelRF. PMID:22369383

  9. In-situ roundness measurement and correction for pin journals in oscillating grinding machines

    NASA Astrophysics Data System (ADS)

    Yu, Hongxiang; Xu, Mengchen; Zhao, Jie

    2015-01-01

    In the mass production of vehicle-engine crankshafts, pin chasing grinding using oscillating grinding machines is a widely accepted method to achieve flexible and efficient performance. However, the eccentric movement of pin journals makes it difficult to develop an in-process roundness measurement scheme for the improvement of contour precision. Here, a new in-situ roundness measurement strategy is proposed with high scanning speed. The measuring mechanism is composed of a V-block and an adaptive telescopic support. The swing pattern of the telescopic support and the V-block is analysed for an equal angle-interval signal sampling. Hence roundness error signal is extracted in frequency domain using a small-signal model of the V-block roundness measurement method and the Fast Fourier Transformation. To implement the roundness data in the CNC coordinate system of an oscillating grinding machine, a transformation function is derived according to the motion model of pin chasing grinding methodology. Computer simulation reveals the relationship between the rotational position of the crankshaft component and the scanning angle of the displacement probe on the V-block, as well as the influence introduced by the rotation centre drift. Prototype investigation indicates the validity of the theoretical analysis and the feasibility of the new strategy.

  10. Electrical measurement system in milling balance machine based on embedded optimization

    NASA Astrophysics Data System (ADS)

    Wang, Yijun; Mei, Yushan

    2015-12-01

    Electrical measurement system in milling balance machine currently consists of micro-controller and peripheral devices. The structure has the problems which include low integration, single signal processing algorithms and great measurement error. Therefore, electrical measurement system in milling balance machine based on embedded optimization is presented in the paper. Firstly, the device control electrical measuring system by ARM subsystem of OMAP dual-core architecture and DSP subsystem realizes digital signal processing and unbalance computing. Also, the low-pass filtering circuit is designed for solving frequency interference. Secondly, the system implement digital band-pass tracking filter based on harmonic wavelet packet. Thirdly, the system extracts any period of weak signal characteristics using the unlimited segmentation features harmonic for wavelet packet signal in the frequency domain. Simulation results show that the system effectively inhibits nearly frequency signal interference, improves signal to noise ratio, and reduces the initial imbalance signal characteristics. And test results improve that precision indexes and technical specifications could meet the design goals.

  11. Measurements of Conversion Efficiency for a Flat Plate Thermophotovoltaic System Using a Photonic Cavity Test System

    SciTech Connect

    E.J. Brown; C.T. Ballinger; S.R. Burger; G.W. Charache; L.R. Danielson; D.M. DePoy; T.J. Donovan; M. LoCascio

    2000-05-30

    The performance of a 1 cm{sup 2} thermophotovoltaic (TPV) module was recently measured in a photonic cavity test system. A conversion efficiency of 11.7% was measured at a radiator temperature of 1076 C and a module temperature of 29.9 C. This experiment achieved the highest direct measurement of efficiency for an integrated TPV system. Efficiency was calculated from the ratio of the peak (load matched) electrical power output and the heat absorption rate. Measurements of these two parameters were made simultaneously to assure the validity of the measured efficiency value. This test was conducted in a photonic cavity which mimicked a typical flat-plate TPV system. The radiator was a large, flat graphite surface. The module was affixed to the top of a copper pedestal for heat absorption measurements. The heat absorption rate was proportional to the axial temperature gradient in the pedestal under steady-state conditions. The test was run in a vacuum to eliminate conductive and convective heat transfer mechanisms. The photonic cavity provides the optimal test environment for TPV efficiency measurements because it incorporates all important physical phenomena found in an integrated TPV system: high radiator emissivity and blackbody spectral shape, photon recycling, Lambertian distribution of incident radiation and complex geometric effects. Furthermore, the large aspect ratio between radiating surface area and radiator/module spacing produces a view factor approaching unity with minimal photon leakage.

  12. Projection Moire measurement of the deflection of composite plates subject to bird strike impact

    NASA Astrophysics Data System (ADS)

    Shulev, A.; Van Paepegem, W.; Harizanova, J.; Moentjens, A.; Degrieck, J.; Sainov, V.

    2007-06-01

    For the new generation aircraft families, the use of fibre-reinforced plastics is considered for the leading edge of the wings. However, this leading edge is very prone to bird strike impact. This paper presents the use of the projection moire technique to measure the out-of-plane deflections of composite plates subject to bird strike. Very strict constraints with regard to: (i) high speed image acquisition, (ii) vibrations of the impact chamber, and (iii) projection and observation angles - complicated substantially the development of the set-up. Moreover, the high frame rates (12000 fps) required a very intensive illumination. In the optimized configuration, a specially designed grating with gradually changing period is projected by means of special Metal Hydride lamps through one of the side windows of the impact chamber onto the composite plate riveted in a steel frame. The digital high speed camera is mounted on the roof of the impact chamber and records through a mirror the object surface with the projected fringe pattern on it. Numerical routines based on Local Fourier Transform were developed to process the digital images, to extract the phase and the out-of-plane displacements. The phase evaluation is possible due to the carrier frequency nature of the projected moire pattern. This carrier frequency allows separation of the unwanted additive and multiplicative fringe pattern components in the frequency domain via the application of a proper mask. The numerical calculations were calibrated for the bird strike of an aluminium plate, where the plastic deformation could be checked after the test.

  13. Ultraviolet absorption measurements of CF2 in the parallel plate pyrolytic chemical vapour deposition process

    NASA Astrophysics Data System (ADS)

    Cruden, Brett A.; Gleason, Karen K.; Sawin, Herbert H.

    2002-03-01

    Polytetrafluoroethylene films have been deposited for use as low dielectric constant materials. Deposition is performed through pyrolysis of hexafluoropropylene oxide (HFPO) to produce CF2, which can then polymerize and deposit as a thin film. The variation of CF2 concentration as a function of reactor conditions has been characterized by ultraviolet absorption spectroscopy. CF2 concentration is observed to go through a maximum with respect to both pressure and pyrolysis temperature when it is present in large amounts (~1014 cm-3). A one-dimensional model including known kinetic reactions for HFPO decomposition and CF2 recombination and multi-component diffusive transport has been applied to the parallel plate system. The result is seen to overestimate the measured concentration and does not capture the maxima observed versus pressure and temperature. An additional mechanism of particle formation, by CF2 insertion into (CF2)n oligomers, has been introduced to produce a kinetic model that explains the CF2 concentration measurements.

  14. Experimental determination of the self-absorption factor for MTR plates by passive gamma spectrometric measurement

    NASA Astrophysics Data System (ADS)

    Berndt, R.; Mortreau, P.

    2011-07-01

    The measurement of the absolute activity or the mass of radioactive substances by gamma spectrometry needs to include a correction for the radiation absorption inside the source volume, the so-called self-absorption factor. It depends on geometry and material composition of the source, the detector geometry and on the geometrical arrangement of source and gamma radiation detector; it can be calculated if full information about all that is available. This article however describes how to determine the self-absorption factor from measurements if the radiation sources are plates of uranium fuel with typical parameters of nuclear fuel for MTR reactors and without using detail information on the source geometry, thus allowing easy inspection without relying on - potentially falsified - declarations on the internal properties of the fuel objects and without calculation.

  15. Reflection zone plate wavelength-dispersive spectrometer for ultra-light elements measurements.

    PubMed

    Hafner, Aljoša; Anklamm, Lars; Firsov, Anatoly; Firsov, Alexander; Löchel, Heike; Sokolov, Andrey; Gubzhokov, Renat; Erko, Alexei

    2015-11-16

    We have developed an electron beam excitation ultra-soft X-ray add-on device for a scanning electron microscope with a reflective zone plate mulichannel spectrometer in order to analyse ultra-light elements such as Li and B. This spectrometer has high (λ/Δλ~100) resolving power in the energy range of 45 eV - 1120 eV. Metallic Li samples were examined and fluorescence spectra successfully measured. Energy resolution of 0.49 eV was measured in the ultra-low energy range using the Al L(2,3) line at 71 eV. High sensitivity of Boron detection was demonstrated on a B(4)C sample with layer thicknesses of 1-50 nm, detecting an amount of metallic Boron as small as ~0.57 fg.

  16. Constraints on Pacific plate kinematics and dynamics with global positioning system measurements

    NASA Technical Reports Server (NTRS)

    Dixon, T. H.; Golombek, M. P.; Thornton, C. L.

    1985-01-01

    A measurement program designed to investigate kinematic and dynamic aspects of plate tectonics in the Pacific region by means of satellite observations is proposed. Accuracy studies are summarized showing that for short baselines (less than 100 km), the measuring accuracy of global positioning system (GPS) receivers can be in the centimeter range. For longer baselines, uncertainty in the orbital ephemerides of the GPS satellites could be a major source of error. Simultaneous observations at widely (about 300 km) separated fiducial stations over the Pacific region, should permit an accuracy in the centimeter range for baselines of up to several thousand kilometers. The optimum performance level is based on the assumption of that fiducial baselines are known a priori to the centimeter range. An example fiducial network for a GPS study of the South Pacific region is described.

  17. Production and evaluation of measuring equipment for share viscosity of polymer melts included nanofiller with injection molding machine

    NASA Astrophysics Data System (ADS)

    Kameda, Takao; Sugino, Naoto; Takei, Satoshi

    2016-10-01

    Shear viscosity measurement device was produced to evaluate the injection molding workability for high-performance resins. Observation was possible in shear rate from 10 to 10000 [1/sec] that were higher than rotary rheometer by measuring with a plasticization cylinder of the injection molding machine. The result of measurements extrapolated result of a measurement of the rotary rheometer.

  18. Diagnostic measurements on the great machines conditions of lignite surface mines

    SciTech Connect

    Helebrant, F.; Jurman, J.; Fries, J.

    2005-07-01

    An analysis of the diagnosis of loading and service dependability of a rail-mounted excavator used in surface lignite mining is described. Wheel power vibrations in electric motor bearings and electric motor input bearings to the gearbox were measured in situ, in horizontal, vertical, and axial directions. The data were analyzed using a mathematical relationship. The results are presented in a loading diagram that shows the deterioration and the acceptable lower bound of machine conditions over time. Work is continuing. 5 refs., 1 fig.

  19. Transport of bromide measured by soil coring, suction plates, and lysimeters under transient flow conditions.

    NASA Astrophysics Data System (ADS)

    Kasteel, R.; Pütz, Th.; Vereecken, H.

    2003-04-01

    Lysimeter studies are one step within the registration procedure of pesticides. Flow and transport in these free-draining lysimeters do not reflect the field situation mainly because of the occurence of a zone of local saturation at the lower boundary (seepage face). The objective of this study is to evaluate the impact of flow and transport behaviour of bromide detected with different measuring devices (lysimeters, suction plates, and soil coring) by comparing experimental results with numerical simulations in heterogeneous flow domains. We applied bromide as a small pulse to the bare soil surface (Orthic Luvisol) of the three devices and the displacement of bromide was regurlarly sampled for three years under natural wheather conditions. Based on the mean breakthrough curves we observe experimentally that lysimeters have a lower effective pore-water velocity and exhibit more solute spreading resulting in a larger dispersivity than the suction plates. This can be ascribed to the artefact of the lower boundary. We performed numerical transport simulations in 2-D heterogeneous flow fields (scaling approach) choosing appropriate boundary conditions for the various devices. The simulations allow to follow the temporal evolution of flow and transport processes in the various devices and to gain additional process understanding. We conclude that the model is essentially capable to reproduce the main experimental findings only if we account for the spatial correlation structure of the hydraulic properties, i.e. soil heterogeneity.

  20. Measuring the Slot Machine Zone With Attentional Dual Tasks and Respiratory Sinus Arrhythmia.

    PubMed

    Murch, W Spencer; Chu, Stephanie W M; Clark, Luke

    2017-02-02

    Recent accounts of problematic electronic gaming machine (EGM) gambling have suggested attentional pathology among at-risk players. A putative slot machine zone is characterized by an intense immersion during game play, causing a neglect of outside events and competing goals. Prior studies of EGM immersion have relied heavily upon retrospective self-report scales. Here, the authors attempt to identify behavioral and psychophysiological correlates of the immersion experience. In samples of undergraduate students and experienced EGM users from the community, they tested 2 potential behavioral measures of immersion during EGM use: peripheral target detection and probe-caught mind wandering. During the EGM play sessions, electrocardiogram data were collected for analysis of respiratory sinus arrhythmia (RSA), a measure of calming self-regulation governed by the parasympathetic nervous system. Subjective measures of immersion during the EGM play session were consistently related to risk of problem gambling. Problem gambling score, in turn, significantly predicted decrements in peripheral target detection among experienced EGM users. Both samples showed robust RSA decreases during EGM play, indicating parasympathetic withdrawal, but neither immersion nor gambling risk were related to this change. This study identifies peripheral attention as a candidate for quantifying game immersion and its links with risk of problem gambling, with implications for responsible gambling interventions at both the game and venue levels. (PsycINFO Database Record

  1. Development of AN Optical Measuring System for Geometric Errors of a Miniaturized Machine Tool

    NASA Astrophysics Data System (ADS)

    Kweon, Sung-Hwan; Liu, Yu; Lee, Jae-Ha; Kim, Young-Suk; Yang, Seung-Han

    Recently, miniaturized machine tools (mMT) have become a promising micro/meso-mechanical manufacturing technique to overcome the material limitation and produce complex 3D meso-scale components with higher accuracy. To achieve sub-micron accuracy, geometric errors of a miniaturized machine tool should be identified and compensated. An optic multi-degree-of-freedom (DOF) measuring system, composed of one laser diode, two beam splitters and three position sensing detectors (PSDs), is proposed for simultaneous measurement of horizontal straightness, vertical straightness, pitch, yaw and roll errors along a moving axis of mMT. Homogeneous transformation matrix (HTM) is used to derive the relationship between the readings of PSDs and geometric errors, and an error estimation algorithm is presented to calculate the geometric errors. Simulation is carried out to prove the estimation accuracy of this algorithm. In theory, the measurement resolution of this proposed system can reach up to 0.03 μm and 0.06 arcsec for translational and rotational errors, respectively.

  2. Investigation of the applicability of a tensile testing machine for measuring mucoadhesive strength.

    PubMed

    Dyvik, K; Graffner, C

    1992-01-01

    The applicability of a tensile testing machine (M30K, JJ Lloyd Instruments Ltd, GB) is investigated for measuring mucoadhesive strengths. A sample of an aqueous dispersion of a polymer with expected mucoadhesive properties is placed between two homemade discs of polyoxymethylene. The upper disc is mounted on a movable part of the machine while the lower disc is fixed on the stationary frame. A tensile force is submitted and the maximum detachment force at fracture and the adhesion work are estimated from the force displacement curve recorded. In some experiments, native mucous tissue of the large intestine of pigs was glued to the upper disc. Four polymers polycarbophil (Carbopol EX-55), carboxypolymethylene (Carbopol 934P), hydroxypropylmethylcellulose (Methocel K4M), and sodium alginate, are used in five different concentrations. At least three measurements are made of each polymer and concentration. Viscosity and osmolality are determined. By standardizing the time of sample equilibration and the run rate before measurement, it is possible to get good reproducibility of the tensile values. Based on the maximum nominal breaking force and the work consumed, it is concluded that the tensile strength is dependent both on the concentration and the type of polymer. The conclusions are the same independent of whether mucous pig tissue is used, or not. The same rank order in adhesive properties of the polymers is achieved as from using modified surface tensiometers.

  3. Evaluation of a high-precision gear measuring machine for helix measurement using helix and wedge artifacts

    NASA Astrophysics Data System (ADS)

    Taguchi, Tetsuya; Kondo, Yohan

    2016-08-01

    High-precision gears are required for advanced motion and power transmission. The reliability of the measured value becomes important as the gear accuracy increases, and the establishment of a traceability system is needed. Therefore, a high-precision gear measuring machine (GMM) with a smaller uncertainty is expected to improve the gear calibration uncertainty. For this purpose, we developed a prototype of a high-precision GMM that adopts a direct drive mechanism and other features. Then, the high measurement capability of the developed GMM was verified using gear artifacts. Recently, some new measurement methods using simple shapes such as spheres and planes have been proposed as standards. We have verified the tooth profile measurement using a sphere artifact and reported the results that the developed GMM had a high capability in tooth profile measurement. Therefore, we attempted to devise a new evaluation method for helix measurement using a wedge artifact (WA) whose plane was treated as the tooth flank, and the high measurement capability of the developed GMM was verified. The results will provide a part of information to fully assess measurement uncertainty as our future work. This paper describes the evaluation results of the developed GMM for helix measurement using both a helix artifact and the WA, and discusses the effectiveness of the WA as a new artifact to evaluate the GMMs.

  4. Extending the measuring range of fiber optic displacement sensor with differential evolution optimized extreme learning machine

    NASA Astrophysics Data System (ADS)

    Wang, Xiaodong; Ye, Meiying; Jiang, Minlan

    2013-10-01

    A signal processing method for reflective fiber optic displacement sensor is presented by means of a differential evolution optimized extreme learning machine (DE-ELM). The sensing head of the sensor is a combination of an illuminating fiber bundle transmitting incoming light beam and two receiving fiber bundles employed to collect the reflected beam from the reflector. Three fiber bundles with same type are put together and arranged side by side, but the two receiving fiber bundles enfaces have different distances from the reflector surface. The DE-ELM is used for extending the measuring the range of reflective fiber optic displacement sensor. A simulation experiment has been illustrated. The experimental results show that the measuring range can be extended to the whole response characteristics of the fiber optic displacement sensor and a high measuring accuracy can be obtained by the proposed method.

  5. Error correction with machine learning: one man's syndrome measurement is another man's treasure

    NASA Astrophysics Data System (ADS)

    Combes, Joshua; Briegel, Hans; Caves, Carlton; Cesare, Christopher; Ferrie, Christopher; Milburn, Gerard; Tiersch, Markus

    2014-03-01

    Syndrome measurements that are made in quantum error correction contains more information than is typically used. We show using the data from syndrome measurements (that one has to do anyway) the following: (1) a channel can be dynamically estimated; (2) in some situations the information gathered from the estimation can be used to permanently correct away part of the channel; and (3) can allow us to perform hypothesis testing to determine if the errors are correlated or if the error rate exceeds the ``expected worst case''. The unifying theme to these topics is making use of all of the information in the data collected from syndrome measurements with a machine learning and control algorithms.

  6. Machine learning aided diagnosis of hepatic malignancies through in vivo dielectric measurements with microwaves.

    PubMed

    Yilmaz, Tuba; Kılıç, Mahmut Alp; Erdoğan, Melike; Çayören, Mehmet; Tunaoğlu, Doruk; Kurtoğlu, İsmail; Yaslan, Yusuf; Çayören, Hüseyin; Arkan, Akif Enes; Teksöz, Serkan; Cancan, Gülden; Kepil, Nuray; Erdamar, Sibel; Özcan, Murat; Akduman, İbrahim; Kalkan, Tunaya

    2016-06-20

    In the past decade, extensive research on dielectric properties of biological tissues led to characterization of dielectric property discrepancy between the malignant and healthy tissues. Such discrepancy enabled the development of microwave therapeutic and diagnostic technologies. Traditionally, dielectric property measurements of biological tissues is performed with the well-known contact probe (open-ended coaxial probe) technique. However, the technique suffers from limited accuracy and low loss resolution for permittivity and conductivity measurements, respectively. Therefore, despite the inherent dielectric property discrepancy, a rigorous measurement routine with open-ended coaxial probes is required for accurate differentiation of malignant and healthy tissues. In this paper, we propose to eliminate the need for multiple measurements with open-ended coaxial probe for malignant and healthy tissue differentiation by applying support vector machine (SVM) classification algorithm to the dielectric measurement data. To do so, first, in vivo malignant and healthy rat liver tissue dielectric property measurements are collected with open-ended coaxial probe technique between 500 MHz to 6 GHz. Cole-Cole functions are fitted to the measured dielectric properties and measurement data is verified with the literature. Malign tissue classification is realized by applying SVM to the open-ended coaxial probe measurements where as high as 99.2% accuracy (F1 Score) is obtained.

  7. Machine learning aided diagnosis of hepatic malignancies through in vivo dielectric measurements with microwaves

    NASA Astrophysics Data System (ADS)

    Yilmaz, Tuba; Alp Kılıç, Mahmut; Erdoğan, Melike; Çayören, Mehmet; Tunaoğlu, Doruk; Kurtoğlu, İsmail; Yaslan, Yusuf; Çayören, Hüseyin; Enes Arıkan, Akif; Teksöz, Serkan; Cancan, Gülden; Kepil, Nuray; Erdamar, Sibel; Özcan, Murat; Akduman, İbrahim; Kalkan, Tunaya

    2016-07-01

    In the past decade, extensive research on dielectric properties of biological tissues led to characterization of dielectric property discrepancy between the malignant and healthy tissues. Such discrepancy enabled the development of microwave therapeutic and diagnostic technologies. Traditionally, dielectric property measurements of biological tissues is performed with the well-known contact probe (open-ended coaxial probe) technique. However, the technique suffers from limited accuracy and low loss resolution for permittivity and conductivity measurements, respectively. Therefore, despite the inherent dielectric property discrepancy, a rigorous measurement routine with open-ended coaxial probes is required for accurate differentiation of malignant and healthy tissues. In this paper, we propose to eliminate the need for multiple measurements with open-ended coaxial probe for malignant and healthy tissue differentiation by applying support vector machine (SVM) classification algorithm to the dielectric measurement data. To do so, first, in vivo malignant and healthy rat liver tissue dielectric property measurements are collected with open-ended coaxial probe technique between 500 MHz to 6 GHz. Cole-Cole functions are fitted to the measured dielectric properties and measurement data is verified with the literature. Malign tissue classification is realized by applying SVM to the open-ended coaxial probe measurements where as high as 99.2% accuracy (F1 Score) is obtained.

  8. Flat-plate techniques for measuring reflectance of macro-algae (Ulva curvata)

    USGS Publications Warehouse

    Ramsey, Elijah W.; Rangoonwala, Amina; Thomsen, Mads Solgaard; Schwarzschild, Arthur

    2012-01-01

    We tested the consistency and accuracy of flat-plate spectral measurements (400–1000 nm) of the marine macrophyte Ulva curvata. With sequential addition of Ulva thallus layers, the reflectance progressively increased from 6% to 9% with six thalli in the visible (VIS) and from 5% to 19% with ten thalli in the near infrared (NIR). This progressive increase was simulated by a mathematical calculation based on an Ulva thallus diffuse reflectance weighted by a transmittance power series. Experimental and simulated reflectance differences that were particularly high in the NIR most likely resulted from residual water and layering structure unevenness in the experimental progression. High spectral overlap existed between fouled and non-fouled Ulva mats and the coexistent lagoon mud in the VIS, whereas in the NIR, spectral contrast was retained but substantially dampened by fouling.

  9. Measurement-device-independent quantum key distribution with q-plate

    NASA Astrophysics Data System (ADS)

    Chen, Dong; Shang-Hong, Zhao; Ying, Sun

    2015-12-01

    The original measurement-device-independent quantum key distribution is reviewed and a modified protocol using rotation invariant photonic state is proposed. A hybrid encoding approach combined polarization qubit with orbit angular momentum qubit is adopted to overcome the polarization misalignment associated with random rotations in long-distance quantum key distribution. The initial encoding and final decoding of information in our MDI-QKD implementation protocol can be conveniently performed in the polarization space, while the transmission is done in the rotation invariant hybrid space. Our analysis indicates that both the secure key rate and transmission distance can be improved with our modified protocol owing to the lower quantum bit error rate. Furthermore, our hybrid encoding approach only needs to insert four q-plates in practical experiment and to overcome the polarization misalignment problem mentioned above without including any feedback control.

  10. High Frequency Transducer Dedicated to the High-resolution in Situ Measurement of the Distance between Two Nuclear Fuel Plates

    NASA Astrophysics Data System (ADS)

    Zaz, G.; Dekkious, A.; Meignen, P. A.; Calzavara, Y.; Le Clézio, E.; Despaux, G.

    Most high flux reactors for research purposes have fuel elements composed of plates and not pencils. The measure of inter-plate distance of a fuel element is tricky since a resolution of a micron is searched to measure plate swellings of about ten microns while the dimension between the plates is close to the millimeter. This measure should provide information about the fuel and particularly its history of irradiation. That is the reason why a solution has been considered: a robust device based upon high frequency ultrasonic probes adapted to the high radiation environment and thinned to 1 mm to be inserted into a 1.8 mm width water channel between two fuel plates. To achieve the expected resolution, the system is excited with frequencies up to 150 MHz. Thanks to a specific signal processing, this device allows the distance measurement through an ultrasonic wave's time of flight. The feasibility of such challenging distance measurement has already been proved with success on a full size irradiated fuel element of the RHF.

  11. Prediction and measurement of heat transfer rates for the shock-induced unsteady laminar boundary layer on a flat plate

    NASA Technical Reports Server (NTRS)

    Cook, W. J.

    1972-01-01

    The unsteady laminar boundary layer induced by the flow-initiating shock wave passing over a flat plate mounted in a shock tube was theoretically and experimentally studied in terms of heat transfer rates to the plate for shock speeds ranging from 1.695 to 7.34 km/sec. The theory presented by Cook and Chapman for the shock-induced unsteady boundary layer on a plate is reviewed with emphasis on unsteady heat transfer. A method of measuring time-dependent heat-transfer rates using thin-film heat-flux gages and an associated data reduction technique are outlined in detail. Particular consideration is given to heat-flux measurement in short-duration ionized shocktube flows. Experimental unsteady plate heat transfer rates obtained in both air and nitrogen using thin-film heat-flux gages generally agree well with theoretical predictions. The experimental results indicate that the theory continues to predict the unsteady boundary layer behavior after the shock wave leaves the trailing edge of the plate even though the theory is strictly applicable only for the time interval in which the shock remains on the plate.

  12. Laser-machined microcavities for simultaneous measurement of high-temperature and high-pressure.

    PubMed

    Ran, Zengling; Liu, Shan; Liu, Qin; Huang, Ya; Bao, Haihong; Wang, Yanjun; Luo, Shucheng; Yang, Huiqin; Rao, Yunjiang

    2014-08-07

    Laser-machined microcavities for simultaneous measurement of high-temperature and high-pressure are demonstrated. These two cascaded microcavities are an air cavity and a composite cavity including a section of fiber and an air cavity. They are both placed into a pressure chamber inside a furnace to perform simultaneous pressure and high-temperature tests. The thermal and pressure coefficients of the short air cavity are ~0.0779 nm/°C and ~1.14 nm/MPa, respectively. The thermal and pressure coefficients of the composite cavity are ~32.3 nm/°C and ~24.4 nm/MPa, respectively. The sensor could be used to separate temperature and pressure due to their different thermal and pressure coefficients. The excellent feature of such a sensor head is that it can withstand high temperatures of up to 400 °C and achieve precise measurement of high-pressure under high temperature conditions.

  13. Precision Measurement of Cylinder Surface Profile on an Ultra-Precision Machine Tool

    NASA Astrophysics Data System (ADS)

    Lee, J. C.; Noh, Y. J.; Arai, Y.; Gao, W.; Park, C. H.

    2009-01-01

    This paper describes the measurement of the surface straightness profile of a cylinder workpiece on an ultra-precision machine tool which has a T-base design with a spindle, an X-slide and a Z-slide. The movement range of the X-slide is 220 mm and that of the Z-slide is 150 mm, which have roller bearings in common. Two capacitive sensors are employed to scan a cylinder workpiece mounted on the spindle along the Z-axis. The straightness error motion of the Z-slide is measured to be approximately 100 nm by the reversal method. The straightness profile of the cylinder workpiece is evaluated to be approximately 400 nm by separation of the motion error, simultaneously.

  14. A simple machine vision-driven system for measuring optokinetic reflex in small animals.

    PubMed

    Shirai, Yoshihiro; Asano, Kenta; Takegoshi, Yoshihiro; Uchiyama, Shu; Nonobe, Yuki; Tabata, Toshihide

    2013-09-01

    The optokinetic reflex (OKR) is useful to monitor the function of the visual and motor nervous systems. However, OKR measurement is not open to all because dedicated commercial equipment or detailed instructions for building in-house equipment is rarely offered. Here we describe the design of an easy-to-install/use yet reliable OKR measuring system including a computer program to visually locate the pupil and a mathematical procedure to estimate the pupil azimuth from the location data. The pupil locating program was created on a low-cost machine vision development platform, whose graphical user interface allows one to compose and operate the program without programming expertise. Our system located mouse pupils at a high success rate (~90 %), estimated their azimuth precisely (~94 %), and detected changes in OKR gain due to the pharmacological modulation of the cerebellar flocculi. The system would promote behavioral assessment in physiology, pharmacology, and genetics.

  15. Apparatus for in-situ nondestructive measurement of Young's modulus of plate structures

    NASA Technical Reports Server (NTRS)

    Huang, Jerry Qixin (Inventor); Perez, Robert J. (Inventor); DeLangis, Leo M. (Inventor)

    2005-01-01

    A method and apparatus for determining stiffness of a plate-like structure including a monolithic or composite laminate plate entails disposing a device for generating an acoustical pulse against a surface of the plate and disposing a detecting device against the same surface spaced a known distance from the pulse-generating device, and using the pulse-generating device to emit a pulse so as to create an extensional wave in the plate. The detecting device is used to determine a time of flight of the wave over the known distance, and the wave velocity is calculated. A Young's modulus of the plate is determined by a processor based on the wave velocity. Methods and apparatus for evaluating both isotropic plates and anisotropic laminates are disclosed.

  16. Instrumentation and Methods to Measure Dynamic Forces During Exercise Using the Horizontal Exercise Machine

    NASA Technical Reports Server (NTRS)

    Figueroa, Fernando

    1999-01-01

    It is hypothesized that bone loss experienced by astronauts in zero gravity conditions may be curtailed by appropriate exercise. According to Wolf's law, bone regenerates when muscles produce stresses by pulling on the bone during daily activity and/or exercise on Earth. To use this theory to prevent or decrease bone loss, one needs to quantify musculoskeletal loads and relate them to bone density changes. In the context of the space program, it is desirable to determine musculoskeletal loads during exercise so that one may make similar measurements on Earth and in space. In this manner, load measurements on Earth may be used as reference to generate similar loads during exercise in space. A research project to investigate the effects of high-resistive exercise to decrease bone density loss underzero-gravity conditions is being carried out in Life Sciences Research Laboratories at NASA JSC. The project consists of a bed-rest study whereby subjects remain in horizontal position for seventeen weeks. During the study, a subset of those subjects executes a regime of resistive exercises in the horizontal exercise machine (HEM). The HEM was designed so that subjects remain horizontal while exercising to minimize gravity loading even during exercise. Bone density of each subject is measured throughout the duration of their participation. The objective of the study is to determine if the resistive exercises are effective in diminishing or eliminating bone loss. My participation in this project relates to instrumentation, measurement, and processing of signals from displacement sensors (optical encoders) and load-cells. Measurement of displacements will be used to determine the motion of the body during exercise, and load measurements will be used (along with displacement data) to determine forces and torques exerted on each section of the body during exercise. Further, I have assisted in specifying new sensors to be added to the HEM and to a new prototype resistive

  17. Measurement of velocity variations along a wave path in the through-thickness direction in a plate.

    PubMed

    Kawashima, Katsuhiro

    2005-01-01

    In this paper there is given a method to predict ultrasonic wave velocity variations along a wave path in the through-thickness direction in a plate from thickness resonance spectra. Thickness resonance spectra are numerically calculated and two simple rules used to predict the entire ultrasonic wave velocity variation are derived. In the calculation, the wave path is assumed to be straight along the thickness direction and the velocity variation is assumed to be either as a parabolic curve dependence or a linear dependence with respect to the distance from the surface and to be symmetric with respect to the plate center. To see if the numerical calculation method is reliable, thickness resonance frequencies of a sample with three-layers were measured by EMAT (electromagnetic acoustic transducer) with a good agreement between the measured and the calculated frequencies. This method can be applied to the ultrasonic measurement of material characteristics, internal stress or various other properties of plate materials.

  18. Photometric calibration of NGS/POSS and ESO/SRC plates using the NOAO PDS measuring engine. II - Surface photometry

    NASA Technical Reports Server (NTRS)

    Cutri, Roc M.; Low, Frank J.; Guhathakurta, Puragra

    1993-01-01

    In this paper we present a method to calibrate surface photometry of faint sources measured from direct photographic plates, such as those of the NGS/POSS and ESO/SRC Sky Survey. This calibration procedure does not require scanning sensitometer spots on the plates, but instead uses measurements of the brightness profiles of many faint stars of known brightness to fit a linearized approximation to the characteristic curve. The approximation is valid for only low- to medium-density emulsions, so this technique is appropriate only for relatively faint emission. Comparison between measurements of representative extended sources on the NGS/POSS and CCD images indicates that surface photometry can be obtained from the Sky Survey plates accurate to 0.1-0.3 mag in the range mu(B) between 23 and 27 and mu(R) between 22 and 26 mag/sq arcsec.

  19. Composite tube and plate manufacturing repeatability as determined by precision measurements of thermal strain

    NASA Astrophysics Data System (ADS)

    Riddle, Lenn A.; Tucker, James R.; Bluth, A. Marcel

    2013-09-01

    Composite materials often carry the reputation of demonstrating high variability in critical material properties. The JWST telescope metering structure is fabricated of several thousand separate composite piece parts. The stringent dimensional stability requirements on the metering structure require the critical thermal strain response of every composite piece be verified either at the billet or piece part level. JWST is a unique composite space structure in that it has required the manufacturing of several hundred composite billets that cover many lots of prepreg and many years of fabrication. The flight billet thermal expansion acceptance criteria limits the coefficient of thermal expansion (CTE) to a tolerance ranging between +/-0.014 ppm/K to +/-0.04 ppm/K around a prescribed nominal when measured from 293 K down to 40 K. The different tolerance values represent different material forms including flat plates and different tube cross-section dimensions. A precision measurement facility was developed that could measure at the required accuracy and at a pace that supported the composite part fabrication rate. The test method and facility is discussed and the results of a statistical process analysis of the flight composite billets are surveyed.

  20. A colorimetric method for the measurement of platelet adhesion in microtiter plates.

    PubMed

    Bellavite, P; Andrioli, G; Guzzo, P; Arigliano, P; Chirumbolo, S; Manzato, F; Santonastaso, C

    1994-02-01

    A procedure for the determination of the adhesion of human platelets to protein-coated culture microwells was developed. The number of platelets was quantitated by measuring the activity of acid phosphatase, a platelet enzyme whose activity is stable independently of platelet stimulation and is not released. Isolated and washed platelets were incubated in 96-well microtiter plates with flat-bottom wells that had been precoated with various compounds, including collagen, fibrinogen, human plasma, and human albumin. At the end of incubation (optimal time: 40-60 min), nonadherent platelets were washed out, adherent platelets were solubilized with Triton X-100, and the acid phosphatase activity was measured by using the substrate p-nitrophenyl phosphate. The p-nitrophenol produced was measured with a microplate reader at 405 nm and the percentage of adhesion was calculated with reference to known platelet standards. ADP and thrombin stimulated platelet adhesion in a dose-dependent manner to fibrinogen and human plasma, but not to human albumin. Platelets adhered to collagen even in the absence of stimulants. Simultaneous evaluation of adhesion and aggregation demonstrated that with ADP as stimulus, but not with thrombin, the two platelet responses were dissociated. Microscopic examination of culture wells showed that most of platelets adhered as single cells and not as aggregates. The sensitivity of this method allowed the assay of platelet adhesion by using only 2.5 x 10(5) platelets/well.

  1. Flowfield measurements in a separated and reattached flat plate turbulent boundary layer. Final report

    SciTech Connect

    Patrick, W.P.

    1987-03-01

    The separation and reattachment of a large-scale, two-dimensional turbulent boundary layer at low subsonic speed on a flat plate has been studied experimentally. The separation bubble was 55 cm long and had a maximum bubble thickness, measured to the height of the mean dividing streamline, of 17 cm, which was twice the thickness of the inlet boundary layer. A combination of laser velocimetry, hot-wire anemometry, pneumatic probing techniques, and flow visualization were used as diagnostics. Principal findings were that an outer inviscid rotational flow was defined which essentially convected over the blockage associated with the inner, viscously dominated bubble recirculation region. A strong backflow region in which the flow moved upstream 100 percent of the time was measured near the test surface over the central 35 percent of the bubble. A laminar backflow boundary layer having pseudo-turbulent characteristics including a log-linear velocity profile was generated under the highly turbulent backflow. Velocity profile shapes in the reversed flow region matched a previously developed universal backflow profile at the upstream edge of the separation region but not in the steady backflow region downstream. A smoke flow visualization movie and hot-film measurements revealed low frequency nonperiodic flapping at reattachment. However, forward flow fraction data at reattachment and mean velocity profiles in the redeveloping boundary layer downstream of reattachment correlated with backward-facing step data when the axial dimension was scaled by the distance from the maximum bubble thickness to reattachment.

  2. Method for in-situ nondestructive measurement of Young's modulus of plate structures

    NASA Technical Reports Server (NTRS)

    Huang, Jerry Qixin (Inventor); Perez, Robert J. (Inventor); DeLangis, Leo M. (Inventor)

    2003-01-01

    A method for determining stiffness of a composite laminate plate entails disposing a device for generating an acoustical pulse against a surface of the plate and disposing a detecting device against the same surface spaced a known distance from the pulse-generating device, and using the pulse-generating device to emit a pulse so as to create an extensional wave in the plate. The detecting device is used to determine a time of flight of the wave over the known distance, and the wave velocity is calculated. A Young's modulus of the plate is determined based on the wave velocity. Methods for both anisotropic and quasi-isotropic laminates are disclosed.

  3. Depth Measurement of Moving Slurry at the Wet End of a Paper Machine

    SciTech Connect

    Abidi, B.R.; Goddard, J.S., Jr.; Hunt, M.A.; Sari-Sarraf, H.; Turner, J.C.

    1999-01-24

    The paper industry has long had a need to better understand and control its papermaking process upstream, specifically at the wet end in the forming section of a paper machine. A vision-based system is under development that addresses this need by automatically measuring and interpreting the pertinent paper web parameters at the wet end in real time. The wet-end characterization of the paper web by a vision system involves a four-dimensional measurement of the slurry in real time. These measurements include the two-dimensional spatial information, the intensity profile, and the depth profile. This paper describes the real-time depth profile measurement system for the high-speed moving slurry. A laser line-based measurement method is used with a high-speed programmable camera to directly measure slurry height. The camera is programmed with a profile algorithm, producing depth data at fast sampling rates. Analysis and experimentation have been conducted to optimize the system for the characteristics of the slurry and laser line image. On-line experimental results are presented.

  4. Application of machine vision based measurement in precise assembly of miniature parts

    NASA Astrophysics Data System (ADS)

    Zhu, Cui; Wang, Xiaodong; Zhang, Xiwen; Wang, Lin; Luo, Yi

    2010-08-01

    In manufacturing of precise miniature devices, automatic assembly is the trend to replace manual work for better quality and higher yield. Precise measurement is a critical issue during assembly process because the parts are often complicated and quite different in size, shapes, surface condition, etc. The position and orientation error must be determined precisely before assembly. In the developed automatic assembly system, microscopic machine vision and precise linear stages were integrated in the measurement system for higher detection resolution and larger measurement range in working space. As to the extract of contour of parts with different surface condition, dynamic illumination control and different combination of feature detection algorithms were applied. The errors brought by non-perpendicularity among precision linear stages were compensated and the movement errors were reduced with effective measurement strategy. The measuring accuracy was validated with a special fabricated precise template. Assembly tests were done with the developed system and results indicate that the required position and orientation accuracy can be met successfully and consequently the assembly task can be fulfilled.

  5. Calibrators measurement system for headlamp tester of motor vehicle base on machine vision

    NASA Astrophysics Data System (ADS)

    Pan, Yue; Zhang, Fan; Xu, Xi-ping; Zheng, Zhe

    2014-09-01

    With the development of photoelectric detection technology, machine vision has a wider use in the field of industry. The paper mainly introduces auto lamps tester calibrator measuring system, of which CCD image sampling system is the core. Also, it shows the measuring principle of optical axial angle and light intensity, and proves the linear relationship between calibrator's facula illumination and image plane illumination. The paper provides an important specification of CCD imaging system. Image processing by MATLAB can get flare's geometric midpoint and average gray level. By fitting the statistics via the method of the least square, we can get regression equation of illumination and gray level. It analyzes the error of experimental result of measurement system, and gives the standard uncertainty of synthesis and the resource of optical axial angle. Optical axial angle's average measuring accuracy is controlled within 40''. The whole testing process uses digital means instead of artificial factors, which has higher accuracy, more repeatability and better mentality than any other measuring systems.

  6. A refractive tilting-plate technique for measurement of dynamic contact angles.

    PubMed

    Smedley, Gregory T; Coles, Donald E

    2005-06-01

    The contact angle is a critical parameter in liquid interface dynamics ranging from liquid spreading on a solid surface on earth to liquid motion in partially filled containers in space. A refractive tilting-plate technique employing a scanning laser beam is developed to conduct an experimental study of a moving contact line, with the intention of making accurate measurements of the contact angle. The technique shows promise as an accurate and potentially fully automated means to determine the velocity dependence of the contact angle at the intersection of the interface between two transparent fluids with a transparent solid surface. Ray tracing calculations are included to reinforce the measurement concept. The principal experiments were conducted at speeds ranging from 0.05 to 1.00 mm/s, both advancing and receding, using an immiscible liquid pair (nonane/formamide) in contact with glass. The contact angle was found to depend for practical purposes only on the sign of the velocity and not on its magnitude for the range of velocities studied. Other observations revealed a bimodal behavior of the contact line that depends on which liquid first contacts the glass, with resulting drift in the dynamic contact angle with time.

  7. Heuristic planning in feature-based inspection for coordinate measuring machines

    NASA Astrophysics Data System (ADS)

    Delvalle, Robert B.; Merat, Francis L.; Ruegsegger, Steve; Roumina, Kavous

    1993-03-01

    This system is a practical application of intelligent reasoning about the planning and sequencing of inspection tasks performed by a coordinate measuring machine (CMM). This research is part of an Air Force supported effort to develop a feature-based concurrent engineering system using an object-oriented development platform. Manipulation of design, manufacturing, and inspection features (in this system) is unique in that features are transformed into domain specific objects rather than degraded into elementary geometry. The object-oriented platform provides a means for transformation through built-in qualities such as inheritance, tree-search, and a cohesive part/sub-part organization. Inspection features represent not only geometry, but references to a world coordinate system, proper probe approach, and preferred evaluation method. Reasoning through inspection rules forms a single data object which can then be transformed into CMM executable code.

  8. How to measure metallicity from five-band photometry with supervised machine learning algorithms

    NASA Astrophysics Data System (ADS)

    Acquaviva, Viviana

    2016-02-01

    We demonstrate that it is possible to measure metallicity from the SDSS five-band photometry to better than 0.1 dex using supervised machine learning algorithms. Using spectroscopic estimates of metallicity as ground truth, we build, optimize and train several estimators to predict metallicity. We use the observed photometry, as well as derived quantities such as stellar mass and photometric redshift, as features, and we build two sample data sets at median redshifts of 0.103 and 0.218 and median r-band magnitude of 17.5 and 18.3, respectively. We find that ensemble methods, such as random forests of trees and extremely randomized trees and support vector machines all perform comparably well and can measure metallicity with a Root Mean Square Error (RMSE) of 0.081 and 0.090 for the two data sets when all objects are included. The fraction of outliers (objects for which |Ztrue - Zpred| > 0.2 dex) is 2.2 and 3.9 per cent, respectively and the RMSE decreases to 0.068 and 0.069 if those objects are excluded. Because of the ability of these algorithms to capture complex relationships between data and target, our technique performs better than previously proposed methods that sought to fit metallicity using an analytic fitting formula, and has 3× more constraining power than SED fitting-based methods. Additionally, this method is extremely forgiving of contamination in the training set, and can be used with very satisfactory results for sample sizes of a few hundred objects. We distribute all the routines to reproduce our results and apply them to other data sets.

  9. A Machine Learning Approach for Dynamical Mass Measurements of Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Ntampaka, M.; Trac, H.; Sutherland, D. J.; Battaglia, N.; Póczos, B.; Schneider, J.

    2015-04-01

    We present a modern machine learning (ML) approach for cluster dynamical mass measurements that is a factor-of-two improvement over using a conventional scaling relation. Different methods are tested against a mock cluster catalog constructed using halos with mass ≥slant {{10}14} {{M}⊙ }{{\\text{h}}-1} from Multidark’s publicly available N-body MDPL halo catalog. In the conventional method, we use a standard M(σv) power-law scaling relation to infer cluster mass, M, from line of sight (LOS) galaxy velocity dispersion, σv. The resulting fractional mass error distribution is broad, with width Δɛ ≈ 0.87 (68% scatter), and has extended high-error tails. The standard scaling relation can be simply enhanced by including higher-order moments of the LOS velocity distribution. Applying the kurtosis as a correction term to log ({σ }v}) reduces the width of the error distribution to {Δɛ ≈ 0.74 (16% improvement). ML can be used to take full advantage of all the information in the velocity distribution. We employ the Support Distribution Machines (SDMs) algorithm that learns from distributions of data to predict single values. SDMs trained and tested on the distribution of LOS velocities yield Δɛ ≈ 0.46 (47% improvement). Furthermore, the problematic tails of the mass error distribution are effectively eliminated. Decreasing cluster mass errors will improve measurements of the growth of structure and lead to tighter constraints on cosmological parameters.

  10. Two Capacitive Micro-Machined Ultrasonic Transducers for Wind Speed Measurement.

    PubMed

    Bui, Gia Thinh; Jiang, Yu-Tsung; Pang, Da-Chen

    2016-06-02

    This paper presents a new wind speed measurement method using a single capacitive micro-machined ultrasonic transducer (CMUT). The CMUT was arranged perpendicular to the direction of the wind flow, and a reflector was set up a short distance away, facing the CMUT. To reduce the size, weight, cost, and power consumption of conventional ultrasonic anemometers this study proposes two CMUT designs for the measurement of wind speed using either the amplitude of the signal or the time of flight (TOF). Each CMUT with a double array element design can transmit and receive signals in five different operation modes. Experiments showed that the two CMUT designs utilizing the TOF were better than those utilizing the amplitude of the signal for wind speed measurements ranging from 1 m/s to 10 m/s, providing a measurement error of less than 0.2 m/s. These results indicate that the sensitivity of the TOF is independent of the five operation modes.

  11. Two Capacitive Micro-Machined Ultrasonic Transducers for Wind Speed Measurement

    PubMed Central

    Bui, Gia Thinh; Jiang, Yu-Tsung; Pang, Da-Chen

    2016-01-01

    This paper presents a new wind speed measurement method using a single capacitive micro-machined ultrasonic transducer (CMUT). The CMUT was arranged perpendicular to the direction of the wind flow, and a reflector was set up a short distance away, facing the CMUT. To reduce the size, weight, cost, and power consumption of conventional ultrasonic anemometers this study proposes two CMUT designs for the measurement of wind speed using either the amplitude of the signal or the time of flight (TOF). Each CMUT with a double array element design can transmit and receive signals in five different operation modes. Experiments showed that the two CMUT designs utilizing the TOF were better than those utilizing the amplitude of the signal for wind speed measurements ranging from 1 m/s to 10 m/s, providing a measurement error of less than 0.2 m/s. These results indicate that the sensitivity of the TOF is independent of the five operation modes. PMID:27271625

  12. Unsteady heat-flux measurements of second-mode instability waves in a hypersonic flat-plate boundary layer

    NASA Astrophysics Data System (ADS)

    Kegerise, Michael A.; Rufer, Shann J.

    2016-08-01

    In this paper, we report on the application of the atomic layer thermopile (ALTP) heat-flux sensor to the measurement of laminar-to-turbulent transition in a hypersonic flat-plate boundary layer. The centerline of the flat-plate model was instrumented with a streamwise array of ALTP sensors, and the flat-plate model was exposed to a Mach 6 freestream over a range of unit Reynolds numbers. Here, we observed an unstable band of frequencies that are associated with second-mode instability waves in the laminar boundary layer that forms on the flat-plate surface. The measured frequencies, group velocities, phase speeds, and wavelengths of these instability waves are consistent with data previously reported in the literature. Heat flux time series, and the Morlet wavelet transforms of them, revealed the wave-packet nature of the second-mode instability waves. In addition, a laser-based radiative heating system was used to measure the frequency response functions (FRF) of the ALTP sensors used in the wind tunnel test. These measurements were used to assess the stability of the sensor FRFs over time and to correct spectral estimates for any attenuation caused by the finite sensor bandwidth.

  13. Measuring the scatter in the cluster optical richness-mass relation with machine learning

    NASA Astrophysics Data System (ADS)

    Boada, Steven Alvaro

    The distribution of massive clusters of galaxies depends strongly on the total cosmic mass density, the mass variance, and the dark energy equation of state. As such, measures of galaxy clusters can provide constraints on these parameters and even test models of gravity, but only if observations of clusters can lead to accurate estimates of their total masses. Here, we carry out a study to investigate the ability of a blind spectroscopic survey to recover accurate galaxy cluster masses through their line-of- sight velocity dispersions (LOSVD) using probability based and machine learning methods. We focus on the Hobby Eberly Telescope Dark Energy Experiment (HETDEX), which will employ new Visible Integral-Field Replicable Unit Spectrographs (VIRUS), over 420 degree2 on the sky with a 1/4.5 fill factor. VIRUS covers the blue/optical portion of the spectrum (3500 - 5500 A), allowing surveys to measure redshifts for a large sample of galaxies out to z < 0.5 based on their absorption or emission (e.g., [O II], Mg II, Ne V) features. We use a detailed mock galaxy catalog from a semi-analytic model to simulate surveys observed with VIRUS, including: (1) Survey, a blind, HETDEX-like survey with an incomplete but uniform spectroscopic selection function; and (2) Targeted, a survey which targets clusters directly, obtaining spectra of all galaxies in a VIRUS-sized field. For both surveys, we include realistic uncertainties from galaxy magnitude and line-flux limits. We benchmark both surveys against spectroscopic observations with perfect" knowledge of galaxy line-of-sight velocities. With Survey observations, we can recover cluster masses to ˜ 0.1 dex which can be further improved to < 0.1 dex with Targeted observations. This level of cluster mass recovery provides important measurements of the intrinsic scatter in the optical richness-cluster mass relation, and enables constraints on the key cosmological parameter, sigma 8, to < 20%. As a demonstration of the methods

  14. Effect of skew angle on second harmonic guided wave measurement in composite plates

    NASA Astrophysics Data System (ADS)

    Cho, Hwanjeong; Choi, Sungho; Lissenden, Cliff J.

    2017-02-01

    Waves propagating in anisotropic media are subject to skewing effects due to the media having directional wave speed dependence, which is characterized by slowness curves. Likewise, the generation of second harmonics is sensitive to micro-scale damage that is generally not detectable from linear features of ultrasonic waves. Here, the effect of skew angle on second harmonic guided wave measurement in a transversely isotropic lamina and a quasi-isotropic laminate are numerically studied. The strain energy density function for a nonlinear transversely isotropic material is formulated in terms of the Green-Lagrange strain invariants. The guided wave mode pairs for cumulative second harmonic generation in the plate are selected in accordance with the internal resonance criteria - i.e., phase matching and non-zero power flux. Moreover, the skew angle dispersion curves for the mode pairs are obtained from the semi-analytical finite element method using the derivative of the slowness curve. The skew angles of the primary and secondary wave modes are calculated and wave propagation simulations are carried out using COMSOL. Numerical simulations revealed that the effect of skew angle mismatch can be significant for second harmonic generation in anisotropic media. The importance of skew angle matching on cumulative second harmonic generation is emphasized and the accompanying issue of the selection of internally resonant mode pairs for both a unidirectional transversely isotropic lamina and a quasi-isotropic laminate is demonstrated.

  15. Measurements of high frequency vibration using fiber Bragg grating sensors packaged on PZT plate

    NASA Astrophysics Data System (ADS)

    Fang, Qiaofeng; Chen, Wentao; Yin, Zhenyu; Liu, Yunqi

    2014-11-01

    We demonstrate the fiber Bragg grating (FBG) vibration sensors working at a frequency up to 900 kHz. The FBGs were surface-mounted on the piezoelectric (PZT) ceramic, which is used as the vibration sensor head. A nonlinear response was measured with a periodically strong response at the frequencies of 1 kHz, 5 kHz, 12 kHz, 40 kHz, 70 kHz and 400 kHz. Four kind of polymer were used to package the FBG on the PZT plate. The gratings have similar pattern of vibration response with different deviation on the output voltage. The FBGs packaged with the polymer 705B and EPO-TEK 353ND were found to have a better response at lower frequency, while the FBGs packaged with the polymer T120-023-C2 and TRA-BOND F112 have a better response at higher frequency. The sensors could be developed for the real-time monitoring of the large infrastructure.

  16. Results of the NIST National Ball Plate Round Robin.

    PubMed

    Caskey, G W; Phillips, S D; Borchardt, B R

    1997-01-01

    This report examines the results of the ball plate round robin administered by NIST. The round robin was part of an effort to assess the current state of industry practices for measurements made using coordinate measuring machines. Measurements of a two-dimensional ball plate (240 mm by 240 mm) on 41 coordinate measuring machines were collected and analyzed. Typically, the deviations of the reported X and Y coordinates from the calibrated values were within ± 5 μm, with some coordinate deviations exceeding 20.0 μm. One of the most significant observations from these data was that over 75 % of the participants failed to correctly estimate their measurement error on one or more of the ball plate spheres.

  17. Low coherent Linnik interferometer optimized for use in nano-measuring machines

    NASA Astrophysics Data System (ADS)

    Niehues, Jan; Lehmann, Peter; Xie, Weichang

    2012-12-01

    The precise acquisition of three-dimensional geometrical data in micro- and nanotechnologies plays a crucial role in advanced fabrication processes. Scanning white-light interferometry achieves nanometer resolution in the axial direction, but the lateral resolution is far more critical. The requirements for an area-based optical sensor in a nano-measuring machine are very high. The resolution in every dimension and the working distance have to be as high as possible. In contrast to a Mirau interferometer, a Linnik interferometer does not need any optical components in front of the objective lens. This benefit permits both a long working distance and a high lateral resolution. In the EC-funded project ‘NanoCMM’ we developed a Linnik interferometer providing a working distance of more than 5 mm and a lateral resolution of 0.44 µm. This is achieved by near-UV illumination. The interferometer measures the full modulation depth and the rectangular shape of a pitch standard with 0.6 µm pitch length. This article was presented at the 56th International Scientific Colloquium on ‘Precision Engineering and Precision Measurement Technology’ held at Ilmenau University of Technology, Germany, and submitted for publication in the July 2012 special issue of this journal devoted to papers from that meeting.

  18. A PLM-based automated inspection planning system for coordinate measuring machine

    NASA Astrophysics Data System (ADS)

    Zhao, Haibin; Wang, Junying; Wang, Boxiong; Wang, Jianmei; Chen, Huacheng

    2006-11-01

    With rapid progress of Product Lifecycle Management (PLM) in manufacturing industry, automatic generation of inspection planning of product and the integration with other activities in product lifecycle play important roles in quality control. But the techniques for these purposes are laggard comparing with techniques of CAD/CAM. Therefore, an automatic inspection planning system for Coordinate Measuring Machine (CMM) was developed to improve the automatization of measuring based on the integration of inspection system in PLM. Feature information representation is achieved based on a PLM canter database; measuring strategy is optimized through the integration of multi-sensors; reasonable number and distribution of inspection points are calculated and designed with the guidance of statistic theory and a synthesis distribution algorithm; a collision avoidance method is proposed to generate non-collision inspection path with high efficiency. Information mapping is performed between Neutral Interchange Files (NIFs), such as STEP, DML, DMIS, XML, etc., to realize information integration with other activities in the product lifecycle like design, manufacturing and inspection execution, etc. Simulation was carried out to demonstrate the feasibility of the proposed system. As a result, the inspection process is becoming simpler and good result can be got based on the integration in PLM.

  19. Identification of characteristic ELM evolution patterns with Alfven-scale measurements and unsupervised machine learning analysis

    NASA Astrophysics Data System (ADS)

    Smith, David R.; Fonck, R. J.; McKee, G. R.; Diallo, A.; Kaye, S. M.; Leblanc, B. P.; Sabbagh, S. A.

    2016-10-01

    Edge localized mode (ELM) saturation mechanisms, filament dynamics, and multi-mode interactions require nonlinear models, and validation of nonlinear ELM models requires fast, localized measurements on Alfven timescales. Recently, we investigated characteristic ELM evolution patterns with Alfven-scale measurements from the NSTX/NSTX-U beam emission spectroscopy (BES) system. We applied clustering algorithms from the machine learning domain to ELM time-series data. The algorithms identified two or three groups of ELM events with distinct evolution patterns. In addition, we found that the identified ELM groups correspond to distinct parameter regimes for plasma current, shape, magnetic balance, and density pedestal profile. The observed characteristic evolution patterns and corresponding parameter regimes suggest genuine variation in the underlying physical mechanisms that influence the evolution of ELM events and motivate nonlinear MHD simulations. Here, we review the previous results for characteristic ELM evolution patterns and parameter regimes, and we report on a new effort to explore the identified ELM groups with 2D BES measurements and nonlinear MHD simulations. Supported by U.S. Department of Energy Award Numbers DE-SC0001288 and DE-AC02-09CH11466.

  20. Feature measures for the segmentation of neuronal membrane using a machine learning algorithm

    NASA Astrophysics Data System (ADS)

    Iftikhar, Saadia; Godil, Afzal

    2013-12-01

    In this paper, we present a Support Vector Machine (SVM) based pixel classifier for a semi-automated segmentation algorithm to detect neuronal membrane structures in stacks of electron microscopy images of brain tissue samples. This algorithm uses high-dimensional feature spaces extracted from center-surrounded patches, and some distinct edge sensitive features for each pixel in the image, and a training dataset for the segmentation of neuronal membrane structures and background. Some threshold conditions are later applied to remove small regions, which are below a certain threshold criteria, and morphological operations, such as the filling of the detected objects, are done to get compactness in the objects. The performance of the segmentation method is calculated on the unseen data by using three distinct error measures: pixel error, wrapping error, and rand error, and also a pixel by pixel accuracy measure with their respective ground-truth. The trained SVM classifier achieves the best precision level in these three distinct errors at 0.23, 0.016 and 0.15, respectively; while the best accuracy using pixel by pixel measure reaches 77% on the given dataset. The results presented here are one step further towards exploring possible ways to solve these hard problems, such as segmentation in medical image analysis. In the future, we plan to extend it as a 3D segmentation approach for 3D datasets to not only retain the topological structures in the dataset but also for the ease of further analysis.

  1. A distortion-correction method for workshop machine vision measurement system

    NASA Astrophysics Data System (ADS)

    Chen, Ruwen; Huang, Ren; Zhang, Zhisheng; Shi, Jinfei; Chen, Zixin

    2008-12-01

    The application of machine vision measurement system is developing rapidly in industry for its non-contact, high speed, and automation characteristics. However, there are nonlinear distortions in the images which are vital to measuring precision, for the object dimensions are determined by the image properties. People are interested in this problem and put forward some physical model based correction methods which are widely applied in engineering. However, these methods are difficult to be realized in workshop for the images are non-repetitive interfered by the coupled dynamic factors, which means the real imaging is a stochastic process. A new nonlinear distortion correction method based on a VNAR model (Volterra series based nonlinear auto-regressive time series model) is proposed to describe the distorted image edge series. The model parameter vectors are achieved by the laws of data. The distortion-free edges are obtained after model filtering and the image dimensions are transformed to measuring dimensions. Experimental results show that the method is reliable and can be applied to engineering.

  2. Using a coordinate measuring machine to calibrate step gages at world class levels of uncertainty

    SciTech Connect

    Zurcher, N.

    1996-08-01

    The purpose of this paper is to relate some of the experiences of using a coordinate measuring machine (CMM) to calibrate long end standards and step gages at measurement uncertainties of less than 0. 5{mu}m. It is not the intent of this paper to suggest that everyone should return to his or her laboratory and change the way CMMs are operated nor to suggest that the methods discussed here are even the best methods. The intent is to provide some food for thought, based on real experiences, about the use of a CMM to measure at low levels of uncertainty. As will become apparent, a lot of the issues discussed really apply to any dimensional measuring technique operating at low levels of uncertainty, not just a CMM. The discussion in this paper is based on measuring one-dimensional end standards and step gages placed along the x-axis of the Moore M-60 CMM located at the Oak Ridge Metrology Center, which is part of the Oak Ridge Centers for Manufacturing Technology at the Y-12 Plant (formerly used in manufacturing nuclear weapons parts) in Oak Ridge, Tennessee. When the Cold War ended, the U.S. Department of Energy (DOE) pushed to make nuclear weapons technology available to U.S. industry. As part of this technology transfer effort, it was determined that the M-60 could be used by the National Institute of Standards and Technology (NIST) to provide a calibration service for step gages. Previously, U.S. industrialists had to go to Germany for step gage calibrations at the lowest levels of measurement uncertainty. Much of the discussion that follows is based on the process developed to use the M-60 for the NIST calibration.

  3. Nitrotyrosine Density of Rabbit Urinary Bladder Muscle and Mucosa Measured via Western Blotting and 96-Well Plate Analysis.

    PubMed

    Fitzpatrick, Brittany; Schuler, Catherine; Leggett, Robert E; Levin, Robert M

    2012-01-01

    Purpose. Nitrotyrosine was quantitated in rabbit bladder muscle and mucosa using two analytical systems: Western blotting analyses and a 96-well plate quantitative analysis kit. Materials and Methods. Rabbit bladder muscle and mucosa were obtained from control rabbits. For the Western analysis, the samples were loaded into a SDS page gel and then transferred to a PVDF membrane. The optical density was measured using a Kodak Scanner. Using the 96-well plate, the samples and standards were loaded, incubated with primary and secondary antibody, washed and vacuumed with 10x wash buffer three times between each incubation period. Stop buffer was added to the plate and the results were quantified via the plate reader. Results. For both muscle and mucosa tissue, the optical density readings were linear with tissue concentration; the concentration of nitrotyrosine in the mucosa was significantly higher than in the muscle. However, whereas the Western blot analysis is based on relative optical densities, the 96-well plate kit provides a truly quantitative analysis. Discussion. Mucosa tissue displayed a higher density of nitrotyrosine than did detrusor muscle tissue. This may well be due to the significantly higher metabolic activity of the mucosa compared to the muscle.

  4. On the use of the hole-drilling technique for residual stress measurements in thin plates

    NASA Technical Reports Server (NTRS)

    Hampton, R. W.; Nelson, D. V.

    1992-01-01

    The strain gage blind hole-drilling technique may be used to determine residual stresses at and below the surface of components. In this paper, the hole-drilling analysis methodology for thick plates is reviewed, and experimental data are used to evaluate the methodology and to assess its applicability to thin plates. Data on the effects of gage pattern, surface preparation, hole spacing, hole eccentricity, and stress level are also presented.

  5. Performance Assessment of a Plate Beam Splitter for Deep-Ultraviolet Raman Measurements with a Spatial Heterodyne Raman Spectrometer.

    PubMed

    Lamsal, Nirmal; Angel, S Michael

    2016-11-22

    In earlier works, we demonstrated a high-resolution spatial heterodyne Raman spectrometer (SHRS) for deep-ultraviolet (UV) Raman measurements, and showed its ability to measure UV light-sensitive compounds using a large laser spot size. We recently modified the SHRS by replacing the cube beam splitter (BS) with a custom plate beam splitter with higher light transmission, an optimized reflectance/transmission ratio, higher surface flatness, and better refractive index homogeneity than the cube beam splitter. Ultraviolet Raman measurements were performed using a SHRS modified to use the plate beam splitter and a matching compensator plate and compared to the previously described cube beam splitter setup. Raman spectra obtained using the modified SHRS exhibit much higher signals and signal-to-noise (S/N) ratio and show fewer spectral artifacts. In this paper, we discuss the plate beam splitter SHRS design features, the advantages over previous designs, and discuss some general SHRS issues such as spectral bandwidth, S/N ratio characteristics, and optical efficiency.

  6. The influence of cortical end-plate on broadband ultrasound attenuation measurements at the human calcaneus using scanning confocal ultrasound

    NASA Astrophysics Data System (ADS)

    Xia, Yi; Lin, Wei; Qin, Yi-Xian

    2005-09-01

    Quantitative ultrasound (QUS) assessment, including broadband ultrasound attenuation (BUA), is an efficient technique for assessing bone quality in various statuses, e.g., osteoporosis. While assessing trabecular bone loss is essential to bone quality, the existence of cortical bone can substantially reduce the accuracy of BUA measurement. In this study, we developed an approach to quantify the influence of the cortical end-plate in the QUS on 18 cadaver calcanei using both analytical and experimental analyses. A simplified cortical-trabecular-cortical sandwich model has been developed for simulation of wave propagations. Results show that the cortical end-plate has a significant effect on BUA (yielding 8.5+/-3.6 dB/MHz in cortical bone alone), approximately 15% of the BUA value over the whole bone BUA measurement (54.1+/-20.1 dB/MHz). The phenomenon has been predicted by the developed analytical model with a high correlation (r2=0.63,p<0.0001). The data have suggested that the mechanism of the BUA attributed to the cortical end-plate is primarily due to the ultrasonic wave transmission and reflection within the cortical layers. Therefore, the influence of the cortical end-plate in BUA can be quantified and incorporated into the QUS assessment for bone quality, which may provide insight into BUA measurement for accurate diagnosis of bone diseases.

  7. On-line diagnostics of washing machines: design issues for the optimization of the measurement set-up

    NASA Astrophysics Data System (ADS)

    Agostinelli, G.; Paone, N.; Cristalli, C.; Torcianti, B.

    2008-06-01

    This paper discusses some of the relevant aspects that a designer of an on-line test station for washing machine diagnostics based on a single-point laser Doppler vibrometer should consider. In particular, the paper presents a series of experiments useful to answer the two following questions: a) Where to locate the measurement point? b) Does the test need to be done with an external load to be inserted into the rotating drum? Tests have been done on a "good" washing machine and on a machine exhibiting the most frequent defects to be detected in production line. The study of the Operating Deflection Shapes (ODS) of the machine has been used to determine the best area of the machine cabinet where to position the single point laser vibrometer for on-line diagnostics. In order to support the decision whether or not to employ an artificial unbalance load inserted into the drum during the dynamic test, measurements have been repeated with and without load. Results have been analysed to highlight pros and cons of the use of an external load.

  8. Using Support Vector Machines to Detect Therapeutically Incorrect Measurements by the MiniMed CGMS®

    PubMed Central

    Bondia, Jorge; Tarín, Cristina; García-Gabin, Winston; Esteve, Eduardo; Fernández-Real, José Manuel; Ricart, Wifredo; Vehí, Josep

    2008-01-01

    Background Current continuous glucose monitors have limited accuracy mainly in the low range of glucose measurements. This lack of accuracy is a limiting factor in their clinical use and in the development of the so-called artificial pancreas. The ability to detect incorrect readings provided by continuous glucose monitors from raw data and other information supplied by the monitor itself is of utmost clinical importance. In this study, support vector machines (SVMs), a powerful statistical learning technique, were used to detect therapeutically incorrect measurements made by the Medtronic MiniMed CGMS®. Methods Twenty patients were monitored for three days (first day at the hospital and two days at home) using the MiniMed CGMS. After the third day, the monitor data were downloaded to the physician's computer. During the first 12 hours, the patients stayed in the hospital, and blood samples were taken every 15 minutes for two hours after meals and every 30 minutes otherwise. Plasma glucose measurements were interpolated using a cubic method for time synchronization with simultaneous MiniMed CGMS measurements every five minutes, obtaining a total of 2281 samples. A Gaussian SVM classifier trained on the monitor's electrical signal and glucose estimation was tuned and validated using multiple runs of k-fold cross-validation. The classes considered were Clarke error grid zones A+B and C+D+E. Results After ten runs of ten-fold cross-validation, an average specificity and sensitivity of 92.74% and 75.49%, respectively, were obtained (see Figure 4). The average correct rate was 91.67%. Conclusions Overall, the SVM performed well, in spite of the somewhat low sensitivity. The classifier was able to detect the time intervals when the monitor's glucose profile could not be trusted due to incorrect measurements. As a result, hypoglycemic episodes missed by the monitor were detected. PMID:19885238

  9. MEASUREMENT OF INDOOR AIR EMISSIONS FROM DRY-PROCESS PHOTOCOPY MACHINES

    EPA Science Inventory

    The article provides background information on indoor air emissions from office equipment, with emphasis on dry-process photocopy machines. The test method is described in detail along with results of a study to evaluate the test method using four dry-process photocopy machines. ...

  10. Changes in Late Cretaceous-Quaternary Caribbean plate motion directions inferred from paleostress measurements from striated fault planes

    NASA Astrophysics Data System (ADS)

    Batbayar, K.; Mann, P.; Hippolyte, J.

    2013-12-01

    We compiled paleostress analyses from previous research works collected at 591 localities of striated fault planes in rocks ranging in age from Late Cretaceous to Quaternary in the circum-Caribbean and Mexico. The purpose of the study is to quantify a progressive clockwise rotation of the Caribbean plate during its Late Cretaceous to recent subduction of the Proto-Caribbean seaway. Paleostress analysis is based on the assumption that slickenside lineations indicate both the direction and sense of maximum resolved shear stress on that fault plane. We have plotted directions of maximum horizontal stress onto plate tectonic reconstructions of the circum-Caribbean plate boundaries and infer that these directions are proxies for paleo-plate motion directions of the Caribbean plate. Plotting these stress directions onto reconstructions provided a better visualization of the relation of stress directions to blocks at their time of Late Cretaceous to recent deformation. Older, more deformed rocks of Late Cretaceous to Eocene ages yield a greater scatter in derived paleostress directions as these rocks have steeper dips, more pervasive faulting, and were likely affected by large rotations as known from previous paleomagnetic studies of Caribbean plate margins. Despite more scatter in measurements from older rock units, four major events that affected the Caribbean plate and the Great Arc of the Caribbean (GAC) are recognizable from changing orientations of stress directions: 1) Late Cretaceous collision of the GAC with southern Mexico and Colombia is consistent with NE directions of maximum compression in rocks of this age range in southern Mexico and EW directions in Colombia as the GAC approached the Proto-Caribbean seaway; 2) Paleocene-Eocene collision of the GAC with the Bahamas platform in Cuba and Hispaniola and with the South American plate in Venezuela is consistent with CW rotations of stress directions in rocks of these ages in the northern Caribbean and CCW

  11. Design and implementation of an x-ray strain measurement capability using a rotating anode machine

    SciTech Connect

    Roberts, J.A.; Rangaswamy, P.; Lujan, M. Jr.; Bourke, M.A.M.

    1998-12-31

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Residual stresses close to the surface can improve the reliability and lifetime of parts for technological applications. X-ray diffraction plays a significant role in gaining an exact knowledge of the stresses at the surface and their depth distribution. An x-ray capability at Los Alamos is key to developing and maintaining industrial collaborations in strain effects. To achieve this goal, the authors implemented a residual strain measuring station on the rotating anode x-ray instrument at the Lujan Center. This capability has been used to investigate residual strains in heat treated automotive components, machining effects on titanium alloys, resistance welded steel joints, titanium matrix fiber reinforced composites, ceramic matrix composites, thin films, and ceramic coatings. The overall objective is to combine both x-ray and neutron diffraction measurements with numerical models (e.g., finite element calculations).

  12. Laser-Machined Microcavities for Simultaneous Measurement of High-Temperature and High-Pressure

    PubMed Central

    Ran, Zengling; Liu, Shan; Liu, Qin; Huang, Ya; Bao, Haihong; Wang, Yanjun; Luo, Shucheng; Yang, Huiqin; Rao, Yunjiang

    2014-01-01

    Laser-machined microcavities for simultaneous measurement of high-temperature and high-pressure are demonstrated. These two cascaded microcavities are an air cavity and a composite cavity including a section of fiber and an air cavity. They are both placed into a pressure chamber inside a furnace to perform simultaneous pressure and high-temperature tests. The thermal and pressure coefficients of the short air cavity are ∼0.0779 nm/°C and ∼1.14 nm/MPa, respectively. The thermal and pressure coefficients of the composite cavity are ∼32.3 nm/°C and ∼24.4 nm/MPa, respectively. The sensor could be used to separate temperature and pressure due to their different thermal and pressure coefficients. The excellent feature of such a sensor head is that it can withstand high temperatures of up to 400 °C and achieve precise measurement of high-pressure under high temperature conditions. PMID:25106018

  13. Supercontinuum based absorption spectrometer for cycle-resolved multiparameter measurements in a rapid compression machine.

    PubMed

    Werblinski, Thomas; Kleindienst, Stefan; Engelbrecht, Rainer; Zigan, Lars; Will, Stefan

    2016-06-10

    A broadband supercontinuum (SC) based absorption spectrometer capable of cycle-resolved multiparameter measurements at internal combustion (IC) engine conditions is presented. Three parameters, temperature, pressure and water mole fraction, were extracted from broadband near-infrared H2O absorption spectra, spanning the wavelength-range from 1340 to 1405.5 nm, which exhibits a large number of specific H2O transitions. The spectrometer is based on spatial domain detection and features a near-infrared line scan camera as a detector. Measurements were performed during a compression cycle of a rapid compression machine comprising a pressure and temperature range from 2.5 to 65 bar and 300 to 900 K, respectively. With the new spectrometer, we are for the first time, based on the authors' knowledge, able to perform measurements based on SC radiation over a complete compression and expansion stroke at measurement rates up to 50 kHz. A detailed overview is provided about the best match algorithm between theory and experiments, including parameters from two different spectral databases, namely the Barber-Tennyson database (BT2) and HITRAN2012. The results indicate that spectral broadening effects are not properly described by theory, especially at pressure levels exceeding 20 bar, which culminates in a clear underestimation of the derived pressure data by SC absorption spectroscopy. Nevertheless, temperature can be determined accurately by performing a three-parameter fit based on water mole fraction, temperature, and pressure. In contrast, making use of pressure transducer data as look-up values and varying only temperature and H2O mole fraction to find the best match leads to a clear overestimation of temperature at elevated pressures.

  14. Machine learning based vesselness measurement for coronary artery segmentation in cardiac CT volumes

    NASA Astrophysics Data System (ADS)

    Zheng, Yefeng; Loziczonek, Maciej; Georgescu, Bogdan; Zhou, S. Kevin; Vega-Higuera, Fernando; Comaniciu, Dorin

    2011-03-01

    Automatic coronary centerline extraction and lumen segmentation facilitate the diagnosis of coronary artery disease (CAD), which is a leading cause of death in developed countries. Various coronary centerline extraction methods have been proposed and most of them are based on shortest path computation given one or two end points on the artery. The major variation of the shortest path based approaches is in the different vesselness measurements used for the path cost. An empirically designed measurement (e.g., the widely used Hessian vesselness) is by no means optimal in the use of image context information. In this paper, a machine learning based vesselness is proposed by exploiting the rich domain specific knowledge embedded in an expert-annotated dataset. For each voxel, we extract a set of geometric and image features. The probabilistic boosting tree (PBT) is then used to train a classifier, which assigns a high score to voxels inside the artery and a low score to those outside. The detection score can be treated as a vesselness measurement in the computation of the shortest path. Since the detection score measures the probability of a voxel to be inside the vessel lumen, it can also be used for the coronary lumen segmentation. To speed up the computation, we perform classification only for voxels around the heart surface, which is achieved by automatically segmenting the whole heart from the 3D volume in a preprocessing step. An efficient voxel-wise classification strategy is used to further improve the speed. Experiments demonstrate that the proposed learning based vesselness outperforms the conventional Hessian vesselness in both speed and accuracy. On average, it only takes approximately 2.3 seconds to process a large volume with a typical size of 512x512x200 voxels.

  15. Characterization of the volume and shape of quasi-spherical resonators using coordinate measurement machines

    NASA Astrophysics Data System (ADS)

    de Podesta, M.; May, E. F.; Mehl, J. B.; Pitre, L.; Gavioso, R. M.; Benedetto, G.; Giuliano Albo, P. A.; Truong, D.; Flack, D.

    2010-10-01

    Acoustic thermometry using a gas-filled quasi-spherical resonator (QSR) is one of the most promising techniques for measuring the Boltzmann constant kB with low uncertainty. Dimensional metrology with coordinate measurement machines (CMMs) can be used to determine the resonator's volume, either directly or in combination with measurements of the resonator's microwave spectra. We assessed the uncertainty achievable when using a CMM to characterize the shape and volume of three QSRs. The resonators differed significantly in their design and construction: their inner volumes ranged between 524 cm3 and 2225 cm3, while the QSR geometries ranged from a diamond-turned triaxial ellipsoid to the variable misalignment of spheroidal hemispheres. Comparative coordinate measurements of two solid spherical density standards were used to identify and estimate type B uncertainties. We tested the regression of the CMM data to spherical harmonic expansions and determined the volume of a QSR directly with a relative uncertainty uR < 30 parts in 106. Additionally, spherical harmonic regression of the CMM data can place uncertainty bounds on the eccentricity parameters, ε1 and ε2, typically with a relative uncertainty uR ≈ 0.02. This is sufficient to determine corrections to both the acoustic and the microwave resonance frequencies of the QSR with a relative uncertainty uR < 1 part in 106 for all resonances. These figures assume that the enclosed volume of an assembled QSR is equal to the sum of the volumes of its two component 'hemispheres'. In practice this cannot be strictly true and the additional uncertainties in the volume of the assembled QSR are discussed.

  16. Bibliography of papers, reports, and presentations related to point-sample dimensional measurement methods for machined part evaluation

    SciTech Connect

    Baldwin, J.M.

    1996-04-01

    The Dimensional Inspection Techniques Specification (DITS) Project is an ongoing effort to produce tools and guidelines for optimum sampling and data analysis of machined parts, when measured using point-sample methods of dimensional metrology. This report is a compilation of results of a literature survey, conducted in support of the DITS. Over 160 citations are included, with author abstracts where available.

  17. A new parallel plate shear cell for in situ real-space measurements of complex fluids under shear flow.

    PubMed

    Wu, Yu Ling; Brand, Joost H J; van Gemert, Josephus L A; Verkerk, Jaap; Wisman, Hans; van Blaaderen, Alfons; Imhof, Arnout

    2007-10-01

    We developed and tested a parallel plate shear cell that can be mounted on top of an inverted microscope to perform confocal real-space measurements on complex fluids under shear. To follow structural changes in time, a plane of zero velocity is created by letting the plates move in opposite directions. The location of this plane is varied by changing the relative velocities of the plates. The gap width is variable between 20 and 200 microm with parallelism better than 1 microm. Such a small gap width enables us to examine the total sample thickness using high numerical aperture objective lenses. The achieved shear rates cover the range of 0.02-10(3) s(-1). This shear cell can apply an oscillatory shear with adjustable amplitude and frequency. The maximum travel of each plate equals 1 cm, so that strains up to 500 can be applied. For most complex fluids, an oscillatory shear with such a large amplitude can be regarded as a continuous shear. We measured the flow profile of a suspension of silica colloids in this shear cell. It was linear except for a small deviation caused by sedimentation. To demonstrate the excellent performance and capabilities of this new setup we examined shear induced crystallization and melting of concentrated suspensions of 1 microm diameter silica colloids.

  18. Application of the HHT Method to the Non-contact Thickness Measurement of an Axially Moving Thin Plate

    NASA Astrophysics Data System (ADS)

    Wu, Yangfang; Lu, Qianqian; Xia, Chunlin; Ding, Fan

    2016-06-01

    Non-contact thickness measuring systems can be found in a wide spectrum of technologies. In this paper, Hilbert-Huang transform method is used to analyze the real time signals of a measuring system which includes two round conveyor strings carrying a thin plate, a solar wafer as a sample under test. The vibrations of moving strings and the plate, which are sensitive to moving speed and initial tension in the string, are introduced briefly; the relevant analyses should be helpful for the system design. Using EMD-based time-domain filtering and complementary method, thickness variations and error bands are estimated for different cases. The results show that HHT method as an adaptive time-frequency method, should be potential in measurement engineering applications.

  19. A correction method using a support vector machine to minimize hematocrit interference in blood glucose measurements.

    PubMed

    Shin, Jaeyeon; Park, Hodong; Cho, Sungpil; Nam, Hakhyun; Lee, Kyoung-Joung

    2014-09-01

    Point-of-care testing glucose meters are widely used, important tools for determining the blood glucose levels of people with diabetes, patients in intensive care units, pregnant women, and newborn infants. However, a number of studies have concluded that a change in hematocrit (Hct) levels can seriously affect the accuracy of glucose measurements. The aim of this study was to develop an algorithm for glucose calculation with improved accuracy using the Hct compensation method that minimizes the effects of Hct on glucose measurements. The glucose concentrations in this study were calculated with an adaptive calibration curve using linear fitting prediction and a support vector machine, which minimized the bias in the glucose concentrations caused by the Hct interference. This was followed by an evaluation of performance according to the international organization for standardization (ISO) 15197:2013 based on bias with respect to the reference method, the coefficient of variation, and the valid blood samples/total blood samples within the ±20% and 15% error grids. Chronoamperometry was performed to verify the effect of Hct variation and to compare the proposed method. As a result, the average coefficients of variation for chronoamperometry and the Hct compensation method were 2.43% and 3.71%, respectively, while the average biases (%) for these methods were 12.08% and 5.69%, respectively. The results of chronoamperometry demonstrated that a decrease in Hct levels increases glucose concentrations, whereas an increase in Hct levels reduces glucose concentrations. Finally, the proposed method has improved the accuracy of glucose measurements compared to existing chronoamperometry methods.

  20. 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.

  1. A machine learning approach to estimate Minimum Toe Clearance using Inertial Measurement Units.

    PubMed

    Santhiranayagam, Braveena K; Lai, Daniel T H; Sparrow, W A; Begg, Rezaul K

    2015-12-16

    Falls are the primary cause of accidental injuries (52%) and one of the leading causes of death in individuals aged 65 and above. More than 50% of falls in healthy older adults are due to tripping while walking. Minimum toe clearance (i.e., minimum height of the toe above the ground during the mid-swing phase - MTC) has been investigated as an indicator of tripping risk. There is increasing demand for practicable gait monitoring using wearable sensors such as Inertial Measurement Units (IMU) comprising accelerometers and gyroscopes due to their wearability, compactness and low cost. A major limitation however, is intrinsic noise making acceleration integration unreliable and inaccurate for estimating MTC height from IMU data. A machine learning approach to MTC height estimation was investigated in this paper incorporating features from both raw and integrated inertial signals to train Generalized Regression Neural Networks (GRNN) models using a hill-climbing feature-selection method. The GRNN based MTC height predictions demonstrated root-mean-square-error (RMSE) of 6.6mm with 9 optimum features for young adults and 7.1mm RMSE with 5 features for the older adults during treadmill walking. The GRNN based MTC height estimation method devised in this project represents approximately 68% less RMSE than other estimation techniques. The research findings show a strong potential for gait monitoring outside the laboratory to provide real-time MTC height information during everyday locomotion.

  2. Automated measurement of mouse social behaviors using depth sensing, video tracking, and machine learning

    PubMed Central

    Hong, Weizhe; Kennedy, Ann; Burgos-Artizzu, Xavier P.; Zelikowsky, Moriel; Navonne, Santiago G.; Perona, Pietro; Anderson, David J.

    2015-01-01

    A lack of automated, quantitative, and accurate assessment of social behaviors in mammalian animal models has limited progress toward understanding mechanisms underlying social interactions and their disorders such as autism. Here we present a new integrated hardware and software system that combines video tracking, depth sensing, and machine learning for automatic detection and quantification of social behaviors involving close and dynamic interactions between two mice of different coat colors in their home cage. We designed a hardware setup that integrates traditional video cameras with a depth camera, developed computer vision tools to extract the body “pose” of individual animals in a social context, and used a supervised learning algorithm to classify several well-described social behaviors. We validated the robustness of the automated classifiers in various experimental settings and used them to examine how genetic background, such as that of Black and Tan Brachyury (BTBR) mice (a previously reported autism model), influences social behavior. Our integrated approach allows for rapid, automated measurement of social behaviors across diverse experimental designs and also affords the ability to develop new, objective behavioral metrics. PMID:26354123

  3. Automated measurement of mouse social behaviors using depth sensing, video tracking, and machine learning.

    PubMed

    Hong, Weizhe; Kennedy, Ann; Burgos-Artizzu, Xavier P; Zelikowsky, Moriel; Navonne, Santiago G; Perona, Pietro; Anderson, David J

    2015-09-22

    A lack of automated, quantitative, and accurate assessment of social behaviors in mammalian animal models has limited progress toward understanding mechanisms underlying social interactions and their disorders such as autism. Here we present a new integrated hardware and software system that combines video tracking, depth sensing, and machine learning for automatic detection and quantification of social behaviors involving close and dynamic interactions between two mice of different coat colors in their home cage. We designed a hardware setup that integrates traditional video cameras with a depth camera, developed computer vision tools to extract the body "pose" of individual animals in a social context, and used a supervised learning algorithm to classify several well-described social behaviors. We validated the robustness of the automated classifiers in various experimental settings and used them to examine how genetic background, such as that of Black and Tan Brachyury (BTBR) mice (a previously reported autism model), influences social behavior. Our integrated approach allows for rapid, automated measurement of social behaviors across diverse experimental designs and also affords the ability to develop new, objective behavioral metrics.

  4. High angular accuracy manufacture method of micro v-grooves based on tool alignment by on-machine measurement.

    PubMed

    Zhang, Xiaodong; Jiang, Lili; Zeng, Zhen; Fang, Fengzhou; Liu, Xianlei

    2015-10-19

    Micro v-groove has found wide applications in optical areas as one of the most important structures. However, its performance is significantly affected by its angular geometry accuracy. The diamond cutting has been commonly used as the fabrication method of micro v-groove, but it is still difficult to guarantee the cutting tool angle, which is limited by the measurement accuracy in the manufacture and mounting of the diamond tool. A cutting tool alignment method based on the on-machine measurement is proposed to improve the fabricated quality of the v-groove angle. An on-machine probe is employed to scan the v-groove geometrical deviation precisely. The system errors model, data processing algorithm and tool alignment methods are analyzed in details. Experimental results show that the measurement standard deviation within 0.01° can be achieved. Retro-reflection mirrors are fabricated and measured finally by the proposed method for verification.

  5. Poster — Thur Eve — 02: Measurement of CT radiation profile width using Fuji CR imaging plate raw data

    SciTech Connect

    Bjarnason, T A; Yang, C J

    2014-08-15

    Measuring the CT collimation width and assessing the shape of the overall profile is a relatively straightforward quality control (QC) measure that impacts both image quality and patient dose, and is often required at acceptance and routine testing. Most CT facilities have access to computed radiography (CR) systems, so performing CT collimation profile assessments using CR plates requires no additional equipment. Previous studies have shown how to effectively use CR plates to measure the radiation profile width. However, a major limitation of the previous work is that the full dynamic range of CR detector plates are not used, since the CR processing technology reduces the dynamic range of the DICOM output to 2{sup 10}, requiring the sensitivity and latitude settings of CR reader to be adjusted to prevent clipping of the CT profile data. Such adjustments to CR readers unnecessarily complicate the QC procedure. These clipping artefacts hinder the ability to accurately assess CT collimation width because the full-width at half maximum value of the penumbras are not properly determined if the maximum dose of the profile is not available. Furthermore, any inconsistencies in the radiation profile shape are lost if the profile plateau is clipped off. In this work we developed an opensource Matlab script for straightforward CT profile width measurements using raw CR data that also allows assessment of the profile shape without clipping, and applied this approach during CT QC.

  6. Detailed measurements and shaping of gate profiles for microchannel-plate-based X-ray framing cameras

    SciTech Connect

    Landen, O.L.; Hammel, B.A.; Bell, P.M.; Abare, A. |; Bradley, D.K. |

    1994-10-03

    Gated, microchannel-plate-based (MCP) framing cameras are increasingly used worldwide for x-ray imaging of subnanosecond laser-plasma phenomena. Large dynamic range (> 1,000) measurements of gain profiles for gated microchannel plates (MCP) are presented. Temporal profiles are reconstructed for any point on the microstrip transmission line from data acquired over many shots with variable delay. No evidence for significant pulse distortion by voltage reflections at the ends of the microstrip is observed. The measured profiles compare well to predictions by a time-dependent discrete dynode model down to the 1% level. The calculations do overestimate the contrast further into the temporal wings. The role of electron transit time dispersion in limiting the minimum achievable gate duration is then investigated by using variable duration flattop gating pulses. A minimum gate duration of 50 ps is achieved with flattop gating, consistent with a fractional transit time spread of {approx} 15%.

  7. Determination of areal sedimentation rates in rivers by using plate sediment trap measurements and flow velocity-settling flux relationship.

    PubMed

    Kozerski, Hans-Peter

    2002-07-01

    Not much is known about sedimentation of organic particles in rivers. Plate sediment traps deployed in fast flowing River Spree and in a slowly flowing side arm yielded trapping rates between 0.7 and 52gDW m(-2) d(-1). A linear regression between flow velocity and trapping rates was used to extrapolate from point measurements to areal average trapping rates, which were 11 gDW m(-2) d(-1) in the side arm and 1.4 gDW m(-2) d(-1) in the free flowing river section. These rates are typical for the River Spree, but different from other rivers. The plate trap measurements provide the basic variables for the sedimentation rate sed = C x W*s(1-V/V(crit,sed)), i.e. concentration of particles (C), sinking velocity (Ws) flow velocity (V), and a threshold velocity (V(crit,sed)).

  8. Development of a System to Measure Austenite Grain Size of Plate Steel Using Laser-Based Ultrasonics

    SciTech Connect

    Lim, C. S.; Hong, S. T.; Yi, J. K.; Choi, S. G.; Oh, K. J.; Nagata, Y.; Yamada, H.; Hamada, N.

    2007-03-21

    A measurement system for austenite grain size of plate steel using laser-based ultrasonics has been developed. At first, the relationship between the ultrasonic attenuation coefficients using longitudinal waves and austenite grain size of samples was investigated in the laboratory experiments. According to the experimental results, the ultrasonic attenuation coefficients showed a good correlation with actual austenite grain sizes. For the next step, the system was installed in a hot rolling pilot plant of plate steel, and it was verified that the austenite grain size could be measured even in the environment of a hot rolling pilot plant. In the experiments, it was also confirmed that the fiber delivery system could deliver Nd:YAG laser beam of 810 mJ/pulse and ultrasonic signals could be obtained successfully.

  9. Direct Measurement of the Effect of Surface Roughness on the Colloidal Forces between a Particle and Flat Plate.

    PubMed

    Suresh; Walz

    1997-12-15

    The van der Waals and electrostatic interaction energies between a single particle and a flat plate were measured using the optical technique of total internal reflection microscopy (TIRM). The particles used were 15-µm-diameter polystyrene latex spheres and the flat plate was a polished BK-7 glass slide. The measurements were performed in aqueous solutions of ionic strength ranging from 3 to 7 mM, and the particle-plate separation distances ranged from approximately 25 to 300 nm. During measurement, the particle was trapped in a secondary energy well formed by the repulsive electrostatic and attractive van der Waals forces; however, the particle was free to undergo Brownian motion at all times. These measurements, which capitalize on the extreme sensitivity of the TIRM technique, are believed to be the first direct measurement of the van der Waals interaction energy in aqueous solutions at separation distances where retardation effects are substantial. Comparison of the measured energy wells with predictions made with traditional energy equations produced only fair agreement; specifically, the measured well depths were consistently lower than predicted. However, when the measured results were compared with predictions made using the recent model of L. Suresh and J. Y. Walz ([J. Colloid Interface Sci. 183, 199 (1996)] for rough surfaces, very good agreement was obtained. The asperity heights yielding the best agreement ranged between 14 and 33 nm, with an average height of 26 nm. This value is consistent with previous estimates of the roughness height obtained by measuring the particle sedimentation velocity [J. Y. Walz and L. Suresh, J. Chem. Phys. 103, 10714 (1995)]. Copyright 1997 Academic Press.

  10. Universal precautions and dedicated machines as cheap and effective measures to control HCV spread.

    PubMed

    Cerrai, T; Michelassi, S; Ierpi, C; Toti, G; Zignego, A L; Lombardi, M

    1998-01-01

    Haemodialysis patients are at great risk for HCV infection, and a strict relationship is clear between anti-HCV positivity and dialysis age or hospital dialysis, irrespective of previous blood transfusions. Notwithstanding that, the precise root of its nosocomial nontransfusional diffusion among haemodialysis patients is not clear yet. As isolation is a very expensive policy, we evaluated whether simpler measures such as the observance of the Universal Precautions (UP), and the use of anti-HCV positive patient dedicated monitors can stop the diffusion of HCV infection in a hospital haemodialysis centre. Since January 1990 to December 1991 (1st phase), the patients shared the monitors irrespective of their serological status for HCV, and training of the dialysis care staff was not performed with regard to the UP. Since January 1991 to June 1996 (2nd phase), according to the UP, strictly personal dialysis-tools were used for all patients, anti-HCV positive patients were assigned to dedicated monitors in defined (not separated) areas of the dialysis rooms and the dialysis care staff was trained to the strict observance of the UP. In the first phase of the follow-up 5 seroconversions occurred; none occurred in the second one. Our study shows that isolation is not required for such patients. We believe that measures such as the application of UP, dedicated machines and continuous training of the care staff, instead of the isolation of positive patients, result in the same efficacy and are cheaper than isolation of positive patients. Therefore they are mandatory for all haemodialysis centres.

  11. Determining the values of second-order surface nonlinearities by measurements with wave plates of different retardations.

    PubMed

    Valev, Ventsislav K; Foerier, Stijn; Verbiest, Thierry

    2009-06-01

    We measured the second harmonic generation response of a thin film consisting of chiral molecules with four wave plates having different retardation coefficients. By means of the fitting procedure described in a previously reported formalism, we demonstrated that a single set of tensor components of second order surface nonlinearities fits all the data. Our results provide clear experimental evidence for the validity of this method, which can find applications in the studies of chiral structures and achiral anisotropic materials.

  12. Application of Shear Plate Interferometry to Jet Diffusion Flame Temperature Measurements

    NASA Technical Reports Server (NTRS)

    VanDerWege, Brad A.; OBrien, Chris J.; Hochgreb, Simone

    1997-01-01

    diagnostics of flames are, however, necessarily limited to detection of radiative emission in the visible range, and offer only qualitative information about the nature of the processes in the flame. In particular, the study sought to understand the structure of the inhibitor-perturbed flames with regard to temperature and species concentration in the outer region of the flame. Whereas thermocouple measurements can be used in ground based studies, their implementation in drop-tower rigs is limited. A possible approach to determine the temperature field around the flame is to use interferometric techniques. The implementation and testing of a shear-plate interferometry technique is described below.

  13. Possibility of measuring the thermal Casimir interaction between a plate and a cylinder attached to a micromachined oscillator

    SciTech Connect

    Decca, R. S.; Fischbach, E.; Klimchitskaya, G. L.; Krause, D. E.; Lopez, D.; Mostepanenko, V. M.

    2010-11-15

    We investigate the possibility of measuring the thermal Casimir force and its gradient in the configuration of a plate and a microfabricated cylinder attached to a micromachined oscillator. The Lifshitz-type formulas in this configuration are derived using the proximity force approximation. The accuracy of the obtained expressions is determined from a comparison with exact results available in ideal metal case. Computations of the thermal correction to both the Casimir force and its gradient are performed in the framework of different theoretical approaches proposed in the literature. The correction to the Casimir force and its gradient due to lack of parallelism of the plate and cylinder is determined using the nonmultiplicative approach. The error introduced in the theory due to the finite length of the cylinder is estimated. We propose that both static and dynamic experiments measuring the thermal Casimir interaction between a cylinder and a plate using a micromachined oscillator can shed additional light on the thermal Casimir force problem. Specifically, it is shown that the static experiment is better adapted for the measurement of thermal effects.

  14. Measurement of the t$\\bar{t}$ cross section at the Run II Tevatron using Support Vector Machines

    SciTech Connect

    Whitehouse, Benjamin Eric

    2010-08-01

    This dissertation measures the t$\\bar{t}$ production cross section at the Run II CDF detector using data from early 2001 through March 2007. The Tevatron at Fermilab is a p$\\bar{p}$ collider with center of mass energy √s = 1.96 TeV. This data composes a sample with a time-integrated luminosity measured at 2.2 ± 0.1 fb-1. A system of learning machines is developed to recognize t$\\bar{t}$ events in the 'lepton plus jets' decay channel. Support Vector Machines are described, and their ability to cope with a multi-class discrimination problem is provided. The t$\\bar{t}$ production cross section is then measured in this framework, and found to be σt$\\bar{t}$ = 7.14 ± 0.25 (stat)-0.86+0.61(sys) pb.

  15. Alternative method for measuring effective focal length of lenses using the front and back surface reflections from a reference plate.

    PubMed

    Kim, Do-Hyun; Shi, Dexiu; Ilev, Ilko K

    2011-09-10

    We present a simple method for measuring the effective focal length without determining the location of principle plane of the lens. The method is based on the measurement of confocal backreflection axial responses from the front and back surfaces of a reference plate with known refractive index and thickness. We proved the concept by measuring the effective focal lengths of thin singlet lenses and complex microscope objectives. The theoretical limit of measurement precision varies depending on the numerical aperture of the lens. This method can provide an alternative focal length measurement method for complex lenses or lenses that are permanently attached to other structures. Measurement errors were analyzed theoretically and improvements in measurement accuracy were discussed.

  16. Measurements of strain at plate boundaries using space based geodetic techniques

    NASA Technical Reports Server (NTRS)

    Robaudo, Stefano; Harrison, Christopher G. A.

    1993-01-01

    We have used the space based geodetic techniques of Satellite Laser Ranging (SLR) and VLBI to study strain along subduction and transform plate boundaries and have interpreted the results using a simple elastic dislocation model. Six stations located behind island arcs were analyzed as representative of subduction zones while 13 sites located on either side of the San Andreas fault were used for the transcurrent zones. The length deformation scale was then calculated for both tectonic margins by fitting the relative strain to an exponentially decreasing function of distance from the plate boundary. Results show that space-based data for the transcurrent boundary along the San Andreas fault help to define better the deformation length scale in the area while fitting nicely the elastic half-space earth model. For subduction type bonndaries the analysis indicates that there is no single scale length which uniquely describes the deformation. This is mainly due to the difference in subduction characteristics for the different areas.

  17. Form-Profiling of Optics Using the Geometry Measuring Machine and the M-48 CMM at NIST

    PubMed Central

    Machkour-Deshayes, Nadia; Stoup, John; Lu, Z. Q. John; Soons, Johannes; Griesmann, Ulf; Polvani, Robert

    2006-01-01

    We are developing an instrument, the Geometry Measuring Machine (GEMM), to measure the profile errors of aspheric and free form optical surfaces, with measurement uncertainties near 1 nm. Using GEMM, an optical profile is reconstructed from local curvatures of a surface, which are measured at points on the optic’s surface. We will describe a prototype version of GEMM, its repeatability with time, a measurements registry practice, and the calibration practice needed to make nanometer resolution comparisons with other instruments. Over three months, the repeatability of GEMM is 3 nm rms, and is based on the constancy of the measured profile of an elliptical mirror with a radius of curvature of about 83 m. As a demonstration of GEMM’s capabilities for curvature measurement, profiles of that same mirror were measured with GEMM and the NIST Moore M-48 coordinate measuring machine. Although the methods are far different, two reconstructed profiles differ by 22 nm peak-to-valley, or 6 nm rms. This comparability clearly demonstrates that with appropriate calibration, our prototype of the GEMM can measure complex-shaped optics. PMID:27274939

  18. Plate Coupling and Transient Events Detection from Geodetic Measurements in Nicoya Peninsula, Costa Rica

    NASA Astrophysics Data System (ADS)

    Jiang, Y.; McCaffrey, R.; Wdowinski, S.; Dixon, T.; Protti, M.; Gonzalez, V. M.; Newman, A. V.; Feng, L.

    2011-12-01

    Aseismic tremor and slow slip events (SSE) are known to perturb the stress field at the plate subduction interface. Nicoya Peninsula in northern Costa Rica is located near the Middle America Trench (MAT), where the Cocos plate subducts underneath Caribbean plate. The subducting Cocos plate contains two types of subducting oceanic crust, East Pacific Rise (EPR) in the northern peninsula and Cocos-Nazca Spreading center (CNS) in the southern peninsula. The two crust types differ in subducting speed and orientation, topography, age and heat flow. This unique geological setting provides an opportunity to investigate the kinematics and dynamics of SSE and tremor. In the Nicoya peninsula SSE are found in high b-value regions and occur approximately every 20 months. However, the location and magnitude of SSE are still uncertain due to limited observations. Here we report additional geodetic observations and use a new GPS time-series inversion scheme to investigate simultaneously both SSE and interseismic locking patterns in the study area and their evolution with time. We solve for the steady inter-seismic velocity field and parameters characterizing SSE including slip amount and duration. A preliminary analysis of continuous and campaign GPS data using the time dependent geodetic inversion software TDefnode [McCaffrey 2009] reveals three slow-slipping patches for events in 2003, 2005, 2007 and 2009. Previous inversion analysis of Outerbridge et al. [2010] of the 2007 SSE identified the two of the three patches, a deep on at depth of ~25 km, and a shallower patch at depth of ~7 km. The third patch identified by our inversion at depth of ~15 km is similar in area and location to that reported by Protti et al. [2004] for the 2003 event.

  19. Fast characterization of aluminum plates with TV-holography measurements of the frequency spectrum of multimode, quasi- monochromatic Lamb waves.

    PubMed

    Deán-Ben, X Luís; Trillo, Cristina; Doval, Angel F; Fernández, José L

    2011-06-01

    We introduce a novel approach for measuring the frequency spectrum of Lamb waves and, subsequently, for obtaining the thickness and the bulk wave velocities of isotropic, homogeneous plates. It is based on Fourier transforming a set of spatial and temporal samples of the acoustic displacement but, in contrast to the traditional approach that employs dense temporal sampling and a reduced set of spatial sampling locations, our data set is a sequence of 2-D high-resolution maps of the instantaneous out-of-plane displacement obtained with TV holography. We have devised three variants to obtain a set of points of the wavenumber-frequency space, based, respectively, on the spatial (1-D or 2-D) and on the spatio-temporal (3-D) Fourier transforms. The whole process to obtain these points can be easily automated and substantial time savings can be achieved, compared with other full-field techniques that require human intervention or with pointwise scanned probes. Experimental demonstration of the three variants with quasimonochromatic multimode Lamb waves in aluminum plates is presented. The characteristic parameters of the plates are calculated by fitting the theoretical model to the experimental points of the frequency spectrum. The analysis of the uncertainties shows that the accuracy of the method is only slightly lower than the accuracy of a previously reported method based on measuring the wavelength of single-modes, for which the data acquisition procedure is much slower.

  20. Surface flatness measurement of quasi-parallel plates employing three-beam interference with strong reference beam

    NASA Astrophysics Data System (ADS)

    Sunderland, Zofia; Patorski, Krzysztof

    2016-12-01

    A big challenge for standard interferogram analysis methods such as Temporal Phase Shifting or Fourier Transform is a parasitic set of fringes which might occur in the analyzed fringe pattern intensity distribution. It is encountered, for example, when transparent glass plates with quasi-parallel surfaces are tested in Fizeau or Twyman-Green interferometers. Besides the beams reflected from the plate front surface and the interferometer reference the beam reflected from the plate rear surface also plays important role; its amplitude is comparable with the amplitude of other beams. In result we face three families of fringes of high contrast which cannot be easily separated. Earlier we proposed a competitive solution for flatness measurements which relies on eliminating one of those fringe sets from the three-beam interferogram and separating two remaining ones with the use of 2D Continuous Wavelet Transform. In this work we cover the case when the intensity of the reference beam is significantly higher than the intensities of two object beams. The main advantage of differentiating beam intensities is the change in contrast of individual fringe families. Processing of such three-beam interferograms is modified but also takes advantage of 2D CWT. We show how to implement this method in Twyman-Green and Fizeau setups and compare this processing path and measurement procedures with previously proposed solutions.

  1. Nonequilibrium Rotational Temperature Measurements over Flat Plates in Hypersonic Rarefied Gas Flow

    NASA Astrophysics Data System (ADS)

    Tsuboi, Nobuyuki; Matsumoto, Yoichiro

    2008-12-01

    An experimental study of the interaction between a shock wave and a boundary layer over a flat plate with a sharp leading edge in hypersonic rarefied gas flow is presented. Experiments in a low-density wind tunnel using an electron beam probe were conducted at the Shock Wave Laboratory, RWTH Aachen, Germany. Rotational temperatures for stagnation temperatures of T0 = 1000 K and Kn = 0.028 based on a reference length of 0.05 m were calculated using Robben and Talbot's method. The rotational temperature profiles at X = 3 mm for LE = 45 and 90 are 100 K larger than those for LE = 30. This means that a bow shock wave in front of the leading edge affects the rotational temperature profiles over the plate. The rotational energy distributions differ from the Maxwell-Boltzmann distributions and they are non-equilibrium distributions. The rotational temperature profiles for α = 12 deg are also 100 K larger than those for α = 0 deg. The feature of the rotational temperature over the plate for α = 12 deg is similar to that for LE = 45 and 90 deg.

  2. Damage assessment of composite plate structures with material and measurement uncertainty

    NASA Astrophysics Data System (ADS)

    Chandrashekhar, M.; Ganguli, Ranjan

    2016-06-01

    Composite materials are very useful in structural engineering particularly in weight sensitive applications. Two different test models of the same structure made from composite materials can display very different dynamic behavior due to large uncertainties associated with composite material properties. Also, composite structures can suffer from pre-existing imperfections like delaminations, voids or cracks during fabrication. In this paper, we show that modeling and material uncertainties in composite structures can cause considerable problem in damage assessment. A recently developed C0 shear deformable locking free refined composite plate element is employed in the numerical simulations to alleviate modeling uncertainty. A qualitative estimate of the impact of modeling uncertainty on the damage detection problem is made. A robust Fuzzy Logic System (FLS) with sliding window defuzzifier is used for delamination damage detection in composite plate type structures. The FLS is designed using variations in modal frequencies due to randomness in material properties. Probabilistic analysis is performed using Monte Carlo Simulation (MCS) on a composite plate finite element model. It is demonstrated that the FLS shows excellent robustness in delamination detection at very high levels of randomness in input data.

  3. Synchrotron measurements of the absolute x-ray quantum efficiency of CsI-coated microchannel plates

    NASA Astrophysics Data System (ADS)

    Rideout, Rob M.; Pearson, James F.; Fraser, George W.; Lees, John E.; Brunton, Adam N.; Bannister, N. P.; Kenter, Almus T.; Kraft, Ralph P.

    1998-11-01

    Two identical CsI-coated, low noise microchannel plate (MCP) detectors were taken to the Daresbury Synchrotron Radiation Source (SRS) to measure their quantum efficiencies over two different energy ranges - 450 eV to 1200 eV and 4.5 eV to 9.5 eV. The SRS was run in low ring current with the beam flux monitored using single wire gas proportional counters. We present accurate measurements of edge-related absolute quantum efficiency features due to the CsI photocathodes. This data will be incorporated into the calibration program of the Advanced X-ray Astrophysical Facility High Resolution Camera.

  4. Modelling and calibration technique of laser triangulation sensors for integration in robot arms and articulated arm coordinate measuring machines.

    PubMed

    Santolaria, Jorge; Guillomía, David; Cajal, Carlos; Albajez, José A; Aguilar, Juan J

    2009-01-01

    A technique for intrinsic and extrinsic calibration of a laser triangulation sensor (LTS) integrated in an articulated arm coordinate measuring machine (AACMM) is presented in this paper. After applying a novel approach to the AACMM kinematic parameter identification problem, by means of a single calibration gauge object, a one-step calibration method to obtain both intrinsic-laser plane, CCD sensor and camera geometry-and extrinsic parameters related to the AACMM main frame has been developed. This allows the integration of LTS and AACMM mathematical models without the need of additional optimization methods after the prior sensor calibration, usually done in a coordinate measuring machine (CMM) before the assembly of the sensor in the arm. The experimental tests results for accuracy and repeatability show the suitable performance of this technique, resulting in a reliable, quick and friendly calibration method for the AACMM final user. The presented method is also valid for sensor integration in robot arms and CMMs.

  5. Automatic River Bed Grain Size Measurement Using Image Processing and Support Vector Machines

    NASA Astrophysics Data System (ADS)

    Bellugi, D.; Nelson, P. A.; Dietrich, W. E.

    2010-12-01

    Gravel-bedded rivers cut through hilly and mountainous areas, driving landscape evolution and creating a diverse habitat upon which river food web ecosystems develop. Our understanding of the mechanics underlying important processes in fluvial geomorphology, hydrodynamics, and aquatic ecology inevitably requires knowledge about the grain size distribution of river bed material. Standard methods of sampling bed surface material may introduce errors due to biases and inadequate sample size. Alternative areal or volumetric sampling procedures are often impractical, particularly in coarse channel beds. Furthermore, all invasive sampling techniques can compromise laboratory flume experiments. These concerns suggest that there is a practical need for a reliable, automated, non-invasive procedure for obtaining the grain size distribution of bed surface material. Although considerable effort has been made to automatically generate grain size distributions using image processing and analysis techniques, the problem remains quite challenging: issues such as varying lighting conditions, partial immersion of particles in water, and heterogeneous mineralogy result in ambiguities that cannot be easily resolved. Feature extraction introduces further biases due to over- or under-segmentation of the image. Moreover, unless the grain distributions are fairly homogeneous between different locations, and images are collected in similar fashion, it is difficult to parametrize any such method in a transferable manner. In this study we present an image processing and machine learning procedure to automatically identify and measure grains from photographic images of gravel-bedded rivers. We apply the state-of-the-art of image segmentation techniques, making use of local cues such as brightness, color, and texture in a multi-scale approach. These cues are globalized using a graph partitioning method on the oriented contour signal. The resulting boundary probability signal is treated by a

  6. Machine Vision-Based Measurement Systems for Fruit and Vegetable Quality Control in Postharvest.

    PubMed

    Blasco, José; Munera, Sandra; Aleixos, Nuria; Cubero, Sergio; Molto, Enrique

    2017-03-14

    Individual items of any agricultural commodity are different from each other in terms of colour, shape or size. Furthermore, as they are living thing, they change their quality attributes over time, thereby making the development of accurate automatic inspection machines a challenging task. Machine vision-based systems and new optical technologies make it feasible to create non-destructive control and monitoring tools for quality assessment to ensure adequate accomplishment of food standards. Such systems are much faster than any manual non-destructive examination of fruit and vegetable quality, thus allowing the whole production to be inspected with objective and repeatable criteria. Moreover, current technology makes it possible to inspect the fruit in spectral ranges beyond the sensibility of the human eye, for instance in the ultraviolet and near-infrared regions. Machine vision-based applications require the use of multiple technologies and knowledge, ranging from those related to image acquisition (illumination, cameras, etc.) to the development of algorithms for spectral image analysis. Machine vision-based systems for inspecting fruit and vegetables are targeted towards different purposes, from in-line sorting into commercial categories to the detection of contaminants or the distribution of specific chemical compounds on the product's surface. This chapter summarises the current state of the art in these techniques, starting with systems based on colour images for the inspection of conventional colour, shape or external defects and then goes on to consider recent developments in spectral image analysis for internal quality assessment or contaminant detection.

  7. Drag measurements of an axisymmetric nacelle mounted on a flat plate at supersonic speeds

    NASA Technical Reports Server (NTRS)

    Flamm, Jeffrey D.; Wilcox, Floyd J., Jr.

    1995-01-01

    An experimental investigation was conducted to determine the effect of diverter wedge half-angle and nacelle lip height on the drag characteristics of an assembly consisting of a nacelle fore cowl from a typical high-speed civil transport (HSCT) and a diverter mounted on a flat plate. Data were obtained for diverter wedge half-angles of 4.0 deg, 6.0 deg, and 8.0 deg and ratios of the nacelle lip height above a flat plate to the boundary-layer thickness (h(sub n)/delta) of approximately 0.87 to 2.45. Limited drag data were also obtained on a complete nacelle/diverter configuration that included fore and aft cowls. Although the nacelle/diverter drag data were not corrected for base pressures or internal flow drag, the data are useful for comparing the relative drag of the configuration tested. The tests were conducted in the Langley Unitary Plan Wind Tunnel at Mach numbers of 1.50, 1.80, 2.10, and 2.40 and Reynolds numbers ranging from 2.00 x 10(exp 6) to 5.00 x 10(exp 6) per foot. The results of this investigation showed that the nacelle/diverter drag essentially increased linearly with increasing h(sub n)/delta except near 1.0 where the data showed a nonlinear behavior. This nonlinear behavior was probably caused by the interaction of the shock waves from the nacelle/diverter configuration with the flat-plate boundary layer. At the lowest h(sub n)/delta tested, the diverter wedge half-angle had virtually no effect on the nacelle/diverter drag. However, as h(sub n)/delta increased, the nacelle/diverter drag increased as diverter wedge half-angle increased.

  8. Measuring the Average Thickness of a Plate Using a Bayesian Method and Free Vibration Data

    DTIC Science & Technology

    2011-09-01

    form, the model is constructed with the implicit assumption that the corrosion is uniform. A more detailed model that included details of the pitting ...PROCEDURE The test specimen was a 0.76m by 0.60m (30” by 24”, 5:4 aspect ratio), 1.55mm (1/16”) thick 6061 -T6 aluminum plate. The density was...considering corrosion effect.” Marine Struc- tures, 21(4):402 – 419. [3] T. Nakai, H. Matsushita, N. Yamamoto, and H. Arai, 2004. “Effect of pitting

  9. Measurement of activity distribution using photostimulable phosphor imaging plates in decommissioned 10 MV medical linear accelerator.

    PubMed

    Fujibuchi, Toshioh; Yonai, Shunsuke; Yoshida, Masahiro; Sakae, Takeji; Watanabe, Hiroshi; Abe, Yoshihisa; Itami, Jun

    2014-08-01

    Photonuclear reactions generate neutrons in the head of the linear accelerator. Therefore, some parts of the linear accelerator can become activated. Such activated materials must be handled as radioactive waste. The authors attempted to investigate the distribution of induced radioactivity using photostimulable phosphor imaging plates. Autoradiographs were produced from some parts of the linear accelerator (the target, upper jaw, multileaf collimator and shielding). The levels of induced radioactivity were confirmed to be non-uniform within each part from the autoradiographs. The method was a simple and highly sensitive approach to evaluating the relative degree of activation of the linear accelerators, so that appropriate materials management procedures can be carried out.

  10. Flight measurements of hinged-plate wing-spoiler hinge moments. [dhc-6 Twin Otter series 100 aircraft

    NASA Technical Reports Server (NTRS)

    Fry, E. B.

    1983-01-01

    Hinge moment of hinged-plate wing spoilers were measured during flight of a twin turboprop airplane modified by the addition of upper and lower wing-surface spoilers. The spoiler-actuating hydraulic cylinders were instrumented to measure the forces required to extend the spoiler panels. Those measurements were converted to moment coefficient form, and are presented as a function of spoiler deployment angle. The hinge-moment data were collected at three flight conditions: with flaps extended at approach speed; with flaps retracted at a low speed; and with flaps retracted at a high speed (C sub L = 1.4, 1.0, and 0.5). In general, the magnitude of measured spoiler hinge moments were lower than predicted. Furthermore, for upper surface spoilers with flaps extended, the hinge moments increased in a discontinuous manner between spoiler deflection 10 and 10.

  11. Optical thickness measurement of mask blank glass plate by the excess fraction method using a wavelength-tuning interferometer

    NASA Astrophysics Data System (ADS)

    Kim, Yangjin; Hibino, Kenichi; Sugita, Naohiko; Mitsuishi, Mamoru

    2013-10-01

    The absolute optical thickness of a 140-mm2 mask blank glass plate 3.1 mm thickness was measured by three-surface interferometry using a wavelength-tuning Fizeau interferometer. The interference order was determined by the excess fraction method. The wavelength of a tunable laser diode was scanned linearly from 632 to 642 nm, and a CCD detector recorded 2000 interference images. Two kinds of optical thicknesses measured by discrete Fourier analysis and phase-shifting were synthesized to obtain the optical thickness with respect to the ordinary refractive index. The optical thickness defined by the group refractive index at the 637 nm central wavelength was measured by wavelength scanning. The optical thickness deviation defined by the ordinary refractive index was measured using tunable phase-shifting. The systematic errors caused by nonlinearity in the wavelength tuning were corrected through correlation analysis between the theoretical and observed interference fringes.

  12. Plating Tank Control Software

    SciTech Connect

    Krafcik, John

    1998-03-01

    The Plating Tank Control Software is a graphical user interface that controls and records plating process conditions for plating in high aspect ratio channels that require use of low current and long times. The software is written for a Pentium II PC with an 8 channel data acquisition card, and the necessary shunt resistors for measuring currents in the millampere range.

  13. Rotatable shear plate interferometer

    DOEpatents

    Duffus, Richard C.

    1988-01-01

    A rotatable shear plate interferometer comprises a transparent shear plate mounted obliquely in a tubular supporting member at 45.degree. with respect to its horizontal center axis. This tubular supporting member is supported rotatably around its center axis and a collimated laser beam is made incident on the shear plate along this center axis such that defocus in different directions can be easily measured.

  14. First measurement of the displacement rate of the Pacific Plate near the Japan Trench after the 2011 Tohoku-Oki earthquake using GPS/acoustic technique

    NASA Astrophysics Data System (ADS)

    Tomita, Fumiaki; Kido, Motoyuki; Osada, Yukihito; Hino, Ryota; Ohta, Yusaku; Iinuma, Takeshi

    2015-10-01

    The subduction rate of an oceanic plate may accelerate after large earthquakes rupture the interplate coupling between the oceanic and overriding continental plates. To better understand postseismic deformation processes in an incoming oceanic plate, we directly measured the displacement rate of the Pacific Plate near the Japan Trench after the 2011 Tohoku-Oki earthquake using a GPS/acoustic technique over a period of 2 years (September 2012 to September 2014). The displacement rate was measured to be 18.0 ± 4.5 cm yr-1 (N302.0°E) relative to the North American Plate, which is almost twice as fast as the predicted interseismic plate motion. Because the sum of steady plate motion and viscoelastic response to the Tohoku-Oki earthquake roughly accounts for the observed displacement rate, we conclude that viscoelastic relaxation is the primary mechanism responsible for postseismic deformation of the Pacific Plate and that significant subduction acceleration did not occur at least not during the observation period.

  15. Quantitative X-ray wavefront measurements of Fresnel zone plate and K-B mirrors using phase retrieval.

    PubMed

    Huang, Xiaojing; Wojcik, Michael; Burdet, Nicolas; Peterson, Isaac; Morrison, Graeme R; Vine, David J; Legnini, Daniel; Harder, Ross; Chu, Yong S; Robinson, Ian K

    2012-10-08

    A scanning coherent diffraction imaging method was used to reconstruct the X-ray wavefronts produced by a Fresnel zone plate (FZP) and by Kirkpatrick-Baez (KB) focusing mirrors. The ptychographical measurement was conducted repeatedly by placing a lithographed test sample at different defocused planes. The wavefronts, recovered by phase-retrieval at well-separated planes, show good consistency with numerical propagation results, which provides a self-verification. The validity of the obtained FZP wavefront was further confirmed with theoretical predictions.

  16. Pulsed ultrasonic comb filtering effect and its applications in the measurement of sound velocity and thickness of thin plates.

    PubMed

    Liu, Jingfei; Declercq, Nico F

    2017-03-01

    An analytical and experimental study of the pulsed ultrasonic comb filtering effect is presented in this work intending to provide a fundamental tool for data analysis and phenomenon understanding in pulsed ultrasonics. The basic types of comb filter, feedforward and feedback filters, are numerically simulated and demonstrated. The characteristic features of comb filters, which include the formula for determining the locations of the spectral peaks or notches and the relationship between its temporal characteristics (relative time delay between constituent pulses) and its spectral characteristics (frequency interval between peaks or notches), are theoretically derived. To demonstrate the applicability of the comb filtering effect, it is applied to measuring the sound velocities and thickness of a thin plate sample. It is proven that the comb filtering effect based method not only is capable of accurate measurements, but also has advantages over the conventional time-of-flight based method in thin plate measurements. Furthermore, the principles developed in this study have potential applications in any pulsed ultrasonic cases where the output signal shows comb filter features.

  17. Lack of correlation between Legionella colonization and microbial population quantification using heterotrophic plate count and adenosine triphosphate bioluminescence measurement.

    PubMed

    Duda, Scott; Baron, Julianne L; Wagener, Marilyn M; Vidic, Radisav D; Stout, Janet E

    2015-07-01

    This investigation compared biological quantification of potable and non-potable (cooling) water samples using pour plate heterotrophic plate count (HPC) methods and adenosine triphosphate (ATP) concentration measurement using bioluminescence. The relationship between these measurements and the presence of Legionella spp. was also examined. HPC for potable and non-potable water were cultured on R2A and PCA, respectively. Results indicated a strong correlation between HPC and ATP measurements in potable water (R = 0.90, p < 0.001). In the make-up water and two cooling towers, the correlations between ATP and HPC were much weaker but statistically significant (make-up water: R = 0.37, p = 0.005; cooling tower 1: R = 0.52, p < 0.001; cooling tower 2: R = 0.54, p < 0.001). For potable and non-potable samples, HPC exhibited higher measurement variability than ATP. However, ATP measurements showed higher microbial concentrations than HPC measurements. Following chlorination of the cooling towers, ATP measurements indicated very low bacterial concentrations (<10 colony-forming units (CFU)/mL) despite high HPC concentrations (>1000 CFU/mL) which consisted primarily of non-tuberculous mycobacteria. HPC concentrations have been suggested to be predictive of Legionella presence, although this has not been proven. Our evaluation showed that HPC or ATP demonstrated a fair predictive capacity for Legionella positivity in potable water (HPC: receiver operating characteristic (ROC) = 0.70; ATP: ROC = 0.78; p = 0.003). However, HPC or ATP correctly classified sites as positive only 64 and 62% of the time, respectively. No correlation between HPC or ATP and Legionella colonization in non-potable water samples was found (HPC: ROC = 0.28; ATP: ROC = 0.44; p = 0.193).

  18. Identification of geometric deviations inherent to multi-axis machine tools based on the pose measurement principle

    NASA Astrophysics Data System (ADS)

    Haitao, Li; Junjie, Guo; Yufen, Deng; Jindong, Wang; Xinrong, He

    2016-12-01

    The laser tracker is an effective instrument for measuring 3D relative displacement in a work volume because its attitude can be freely changed. This paper presents a novel principle to realize the precise calibration of a numerical control (NC) machine tool accurately and quickly; this is the ‘pose measurement principle’, for measuring errors. We also introduce an algorithm for identifying geometric deviations. A NC precise table mounted on a motion axis and a laser tracker are used for the coordinate determination of three fixed points to obtain the pose information of each motion axis, then calculate the pose deviations, and finally identify all the errors. For the error identification, first, according to the definition of geometric errors, we extend the concept of pose deviations, and represent the six geometric errors using a position deviation vector and attitude deviation vector. Next, we geometrically identify the three angular errors and linear errors in order; the error mathematical model for the linear axis and rotary axis are developed, respectively. Moreover, the validity of the calibration algorithm for the base station, measuring points and identification of errors are confirmed by simulations. In the end, the proposed method is applied to a three-axis NC milling machine tool and a rotary table, and then the geometric deviations are identified successfully in 3 h and 2.5 h, respectively. Comparative experiments by means of other instruments also agree well with the proposed method. Thus, the proposed method can be applied to the measurement of the multi-axis machine tool.

  19. Implications of very long baseline interferometry measurements on North American intra-plate crustal deformation

    NASA Technical Reports Server (NTRS)

    Allenby, R. J.

    1979-01-01

    Very Long Baseline Interferometry experiments over the last 1-3/4 years between Owens Valley, CA and Haystack, MA Radio Observatories suggest an upper limit of east-west crustal deformation between the two sites of about 1 cm/yr. In view of the fact that the baseline between the two sites traverses most of the major geological provinces of the United States, this low rate of crustal deformation has direct relevance to intra-plate crustal tectonics. The most active region traversed by this baseline is the Basin and Range province, which was estimated by various researchers to be expanding in an east-west direction at rates of .3 to 1.5 cm/yr. The Colorado Plateau and Rocky Mountain system also appear to be expanding, but at a somewhat lower rate, while east of the Rocky Mountains, the predominant stress appears to be compressional, nearly horizontal, and east to northeast trending.

  20. The direct measurement using an imaging plate for coincidence of radiation centre and laser position in external radiation therapy.

    PubMed

    Terunuma, Toshiyuki; Sakae, Takeji; Nohtomi, Akihiro; Tsunashima, Yoshikazu

    2003-02-21

    A new method of quality assurance has been studied to measure coincidence of the radiation centre and a patient-setup laser position on a transverse plane to the beam at the isocentre. This measurement is achieved by using an imaging plate (IP). When radiation is applied to an IP, the energy is stored as trapped electrons. The number of electrons is decreased by local laser exposure. As a result, the radiation field produced by external beam irradiation is recorded as 'positive' information and the position of the patient-setup laser is recorded as 'negative' on an IP. The advantages of this method are the direct measurement, short time and high resolution. These are required for daily and monthly quality checks. We confirmed the advantage of this method by an experiment using a proton beam.

  1. Enhancing the characterization of bedload transport in rivers using the analogy between the Hertz contact theory and plate hydrophone measurements

    NASA Astrophysics Data System (ADS)

    Barrière, Julien; Oth, Adrien; Schenkluhn, Reimar; Krein, Andreas

    2014-05-01

    Vibration measurements performed with plate or pipe geophone/hydrophone systems are of growing interest for bedload transport monitoring since they allow performing high temporal resolution and continuous records. Our set-up is constituted by a piezoelectric hydrophone acting as a "sediment vibration sensor" in contact with a steel plate located on the streambed. With such an apparatus, the signal processing is generally reduced to power spectral analysis or impact counting. However, a large amount of useful information is contained in the waveform of the impact signal, which conveys the force and the contact time that the bedload imposes on the plate. The wave amplitude is not well constrained because it varies a lot with changing impact location and velocity. The wave frequency is a more relevant parameter, less sensitive to these variables. According to the Hertz contact theory the frequency of the first signal arrival (flexural wave) is directly proportional to the bed-material grain size. Then, an appropriate analysis of the frequency attributes (central frequency, modulation) is needed to estimate the size of bedload particles. In this way, we have developed a complete processing algorithm based on a high dimensional decomposition method (chirplet transform) to get an accurate estimation of the first arrival frequency content. Results on summer flood events in a lowland river show that impacts are well separated by their central frequency and that most of transport occurs during larger peak flows. The portion of coarser sediment which is characterized by low frequencies is preferentially transported during the rising limb whereas the finer sand fraction identified by higher frequencies is transported during both rising and falling limb. Such a processing offers the opportunity to better understand the bedload signature of vibration measurements and is promising in view of quantifying processes of bedload transport and deposition. This final objective of

  2. A wearable force plate system for the continuous measurement of triaxial ground reaction force in biomechanical applications

    NASA Astrophysics Data System (ADS)

    Liu, Tao; Inoue, Yoshio; Shibata, Kyoko

    2010-08-01

    The ambulatory measurement of ground reaction force (GRF) and human motion under free-living conditions is convenient, inexpensive and never restricted to gait analysis in a laboratory environment and is therefore much desired by researchers and clinical doctors in biomedical applications. A wearable force plate system was developed by integrating small triaxial force sensors and three-dimensional (3D) inertial sensors for estimating dynamic triaxial GRF in biomechanical applications. The system, in comparison to existent systems, is characterized by being lightweight, thin and easy-to-wear. A six-axial force sensor (Nitta Co., Japan) was used as a verification measurement device to validate the static accuracy of the developed force plate. To evaluate the precision during dynamic gait measurements, we compared the measurements of the triaxial GRF and the center of pressure (CoP) by using the developed system with the reference measurements made using a stationary force plate and an optical motion analysis system. The root mean square (RMS) differences of the two transverse components (x- and y-axes) and the vertical component (z-axis) of the GRF were 4.3 ± 0.9 N, 6.0 ± 1.3 N and 12.1 ± 1.1 N, respectively, corresponding to 5.1 ± 1.1% and 6.5 ± 1% of the maximum of each transverse component and 1.3 ± 0.2% of the maximum vertical component of GRF. The RMS distance between the two systems' CoP traces was 3.2 ± 0.8 mm, corresponding to 1.2 ± 0.3% of the length of the shoe. Moreover, based on the results of the assessment of the influence of the system on natural gait, we found that gait was almost never affected. Therefore, the wearable system as an alternative device can be a potential solution for measuring CoP and triaxial GRF in non-laboratory environments.

  3. Thermal conductivity of a wide range of alternative refrigerants measured with an improved guarded hot-plate apparatus

    SciTech Connect

    Hammerschmidt, U.

    1995-09-01

    The thermal conductivity of the refrigerants R22, R123, R134a, R142b, R143a, and R152a has been determined as a function of temperature in the range from 300 to 460 K. Measurements were carried out at atmospheric pressure with an improved guarded hot-plate apparatus. The width of the instrument`s gas layer and the temperature difference across the metering section were varied to detect any stray heat transfer. Radiation correction factors were derived from IR absorption spectra. The uncertainty of the measurements is estimated to be 2% at a standard deviation of less than 0.1%. Our data sets are compared with corresponding hot wire results. In contrast to the generally preferred hot wire technique, with its possible electrical and chemical interactions between the wire and the polar refrigerant, there are no such difficulties using a guarded hot-plate apparatus. Our data sets may thus contribute to the discussions on discrepancies in thermal conductivity values from various authors using hot wire as one particular method.

  4. Measuring position in 2-dimensions using induced signals in a microchannel plate detector

    NASA Astrophysics Data System (ADS)

    Wiggins, Blake; Desouza, Romualdo

    2017-01-01

    Position-sensitive microchannel plate (MCP) detectors play an important role in the detection of photons, electrons, ions, and neutrons. Recently, a novel approach has been developed to provide position-sensitivity for an MCP detector. In this approach, namely the induced signal approach, the position of the incident particle is determined by sensing the electron cloud emanating from a MCP stack. The induced signals are inherently bipolar, where the negative lobe of the induced signal corresponds to the approach of the electron cloud to the sense wires and the positive lobe corresponds to the recession of the electron cloud from the sense wires. The zero-crossing point is the time at which the centroid of the charge cloud passes the wire plane. For a single incident electron, a spatial resolution of 103 μm (FWHM) has been achieved by utilizing the zero-crossing point of the induced signals. General considerations suggest that this spatial resolution can be improved by using the entire pulse shape information. The fundamentals of the induced signal approach as well as its implementation in slow neutron radiography will be presented. Supported by the US DOE NNSA under Award No. DE-NA0002012.

  5. Evaluation of a microchannel-plate PMT as a potential timing detector suitable for positron lifetime measurements

    NASA Astrophysics Data System (ADS)

    Kosev, K.; Butterling, M.; Anwand, W.; Cowan, T.; Hartmann, A.; Heidel, K.; Jungmann, M.; Krause-Rehberg, R.; Massarczyk, R.; Schilling, K. D.; Schwengner, R.; Wagner, A.

    2010-12-01

    This paper focuses on the evaluation of a microchannel-plate photomultiplier tube (MCP-PMT) as a candidate detector, suitable for positron lifetime studies. Several properties of MCP-PMTs, such as their fast time response, compact size, low susceptibility to magnetic fields, relatively high gain and the low power consumption make them attractive for positron lifetime spectroscopy. The preliminary tests were performed with a 85001-501 Burle Planacon TM photomultiplier tube assembly. Initial measurements were conducted with a pulsed Picosecond Injection Laser (PiLas) system. The engineering sample of the 85001 exhibits a transit-time-spread (TTS) of 110 ps (FWHM). Further timing experiments showing the suitability of the device as Cherenkov detector are presented. For the first time, a conventional positron lifetime spectrum of a Cz-Si probe measured with a spectrometer, where an MCP-PMT detector is included, has been demonstrated.

  6. Fluctuating pressures measured beneath a high-temperature, turbulent boundary layer on a flat plate at Mach number of 5

    NASA Technical Reports Server (NTRS)

    Parrott, Tony L.; Jones, Michael G.; Albertson, Cindy W.

    1989-01-01

    Fluctuating pressures were measured beneath a Mach 5, turbulent boundary layer on a flat plate with an array of piezoresistive sensors. The data were obtained with a digital signal acquisition system during a test run of 4 seconds. Data sampling rate was such that frequency analysis up to 62.5 kHz could be performed. To assess in situ frequency response of the sensors, a specially designed waveguide calibration system was employed to measure transfer functions of all sensors and related instrumentation. Pressure time histories were approximated well by a Gaussian prohibiting distribution. Pressure spectra were very repeatable over the array span of 76 mm. Total rms pressures ranged from 0.0017 to 0.0046 of the freestream dynamic pressure. Streamwise, space-time correlations exhibited expected decaying behavior of a turbulence generated pressure field. Average convection speed was 0.87 of freestream velocity. The trendless behavior with sensor separation indicated possible systematic errors.

  7. Unsteady boundary layers on a flat plate disturbed by periodic wakes. Part 2: Measurements of unsteady boundary layers and discussion

    SciTech Connect

    Funazaki, K.

    1996-04-01

    As the second part of the study, detailed hot-wire anemometry measurements of wake-affected boundary layers on the flat plate are made. These measurements are organized in order, first, to check the standpoint of the modeling of the wake-induced transition proposed in Part 1, and second, to observe wake-boundary layer interaction in detail from a viewpoint of direct and indirect effect of the wake passage upon turbulent spot generation within the boundary layer, as described by Walker (1993). The validity of the presumed state of the wake-affected boundary layer in the distance-time domain, which constitutes the basis of the transition model, is confirmed to great extent. However, it is also found that the criterion for the onset of the wake-induced transition adopted in Part 1 should be reconsidered. Some successful attempts are therefore made to specify the transition onset.

  8. Measurement of Acoustic Intensity Distribution and Radiation Power of Flat-Plate Phased-Array Sound Source

    NASA Astrophysics Data System (ADS)

    Yokoyama, Tomoki; Takahashi, Kumiko; Seki, Daizaburou; Hasegawa, Akio

    2002-05-01

    The acoustic intensity distribution and radiation power of a flat-plate phased-array sound source consisting of Tonpilz-type transducers were measured. This study shows that the active acoustic intensity is skewed in the direction of wave propagation. In addition, it clarifies that if the measurement is carried out in the immediate vicinity of the sound source, the reactive acoustic intensity distribution is effective for identifying the positions of the individual sound source elements. Experimental values of active radiation power agree well with theoretical values. Conversely, experimental values of reactive radiation power do not agree with theoretical values; it is clear that they fluctuate significantly with distance from the radiating surface. The reason for this is explained in the case of a point sound source.

  9. Digital Copy of the Pulkovo Plate Collection

    NASA Astrophysics Data System (ADS)

    Kanaev, I.; Kanaeva, N.; Poliakow, E.; Pugatch, T.

    Report is devoted to a problem of saving of the Pulkovo plate collection. In total more than 50 thousand astronegatives are stored in the observatory. First of them are dated back to 1893. A risk of emulsion corrupting raises with current of time. Since 1996 the operation on digitization and record of the images of plates on electronic media (HDD, CD) are carried out in the observatory. The database ECSIP - Electronic Collection of the Star Images of the Pulkovo is created. There are recorded in it both complete, and extracted (separate areas) images of astronegatives. The plates as a whole are scanned on the photoscanner with rather rough optical resolution 600-2400 dpi. The matrixes with the separate images are digitized on the precision measuring machine "Fantasy" with high (6000-25400 dpi) resolution. The DB ECSIP allows to accept and to store different types of data of a matrix structure, including, CCD-frames. Structure of the ECSIP's software includes systems of visualization, processing and manipulation by the images, and also programs for position and photometric measurements. To the present time more than 40% completed and 10% extracted images from its total amount are digitized and recorded in DB ECSIP. The project is fulfilled at financial support by the Ministry of Science of Russian Federation, grant 01-54 "The coordinate -measuring astrographic machine "Fantasy".

  10. Preliminary results of processing of Pulkovo series of photographic observations of double star 61 Cygni measured by automatic machine "Fantasy"

    NASA Astrophysics Data System (ADS)

    Gorshanov, D. L.; Shakht, N. A.; Kisselev, A. A.; Polyakov, E. V.; Bronnikova, A. A.; Kanaev, I. I.

    2003-11-01

    Two long-term series of photographic observations of one of the nearest double star 61 Cygni have been obtained at Pulkovo by means of normal astrograph in 1895-2000 (I) and by means of 26'' refractor in 1958-2000 (II). All these observations have been measured by means automatic machine "Fantasy" with mean error of yearly positions 0.016'' and 0.008'' for I and II series correspondly. The periodic deviations with period 6.4 +/- 0.5 yr in the residuals in relative distances between components are noticed for series II.

  11. Unmixing of fluorescence spectra to resolve quantitative time-series measurements of gene expression in plate readers

    PubMed Central

    2014-01-01

    Background To connect gene expression with cellular physiology, we need to follow levels of proteins over time. Experiments typically use variants of Green Fluorescent Protein (GFP), and time-series measurements require specialist expertise if single cells are to be followed. Fluorescence plate readers, however, a standard in many laboratories, can in principle provide similar data, albeit at a mean, population level. Nevertheless, extracting the average fluorescence per cell is challenging because autofluorescence can be substantial. Results Here we propose a general method for correcting plate reader measurements of fluorescent proteins that uses spectral unmixing and determines both the fluorescence per cell and the errors on that fluorescence. Combined with strain collections, such as the GFP fusion collection for budding yeast, our methodology allows quantitative measurements of protein levels of up to hundreds of genes and therefore provides complementary data to high throughput studies of transcription. We illustrate the method by following the induction of the GAL genes in Saccharomyces cerevisiae for over 20 hours in different sugars and argue that the order of appearance of the Leloir enzymes may be to reduce build-up of the toxic intermediate galactose-1-phosphate. Further, we quantify protein levels of over 40 genes, again over 20 hours, after cells experience a change in carbon source (from glycerol to glucose). Conclusions Our methodology is sensitive, scalable, and should be applicable to other organisms. By allowing quantitative measurements on a per cell basis over tens of hours and over hundreds of genes, it should increase our understanding of the dynamic changes that drive cellular behaviour. PMID:24495318

  12. Forming Weld Lands On Metal Plates

    NASA Technical Reports Server (NTRS)

    Weddendorf, Bruce

    1994-01-01

    Forming shoe pounds edge of newly inserted plate workpiece. After many passes of shoe and advances of plate, thick land builds up at edge. Workpiece heated to enable metal to flow without strain hardening. Proposed upset-forming process replaces relatively expensive, time-consuming, and wasteful process in which integral weld lands created by machining metal away from plates everywhere except at lands.

  13. Correlation Electron Temperature Fluctuation Measurements on Alcator C-Mod and ASDEX Upgrade: Cross Machine Comparisons and Transport Model Validation

    NASA Astrophysics Data System (ADS)

    White, A. E.; Creely, A. J.; Freethy, S.; Cao, N.; Conway, G. D.; Goerler, T.; Happel, T.; Howard, N. T.; Inman, C.; Rice, J. E.; Rodriguez Fernandez, P.; Sung, C.; C-Mod, Alcator; Upgrade, Asdex

    2016-10-01

    Correlation Electron Cyclotron Emission diagnostics have been developed for Alcator C-Mod and ASDEX Upgrade. Measurements of long wavelength (ktheta rhos <0.5) electron temperature fluctuations have been measured in the core plasma (0.5 machine comparisons, as well as multi-machine transport model validation, using nonlinear simulations with the GENE and GYRO codes and reduced models such as TGLF. Electron temperature fluctuations, and the correlation with density fluctuations, which can be measured with coupled radiometer / reflectometer diagnostics, provide valuable constraints on gyrokinetic models. Recent results in transport model validation at both C-Mod and AUG are presented. This work is supported by the US DOE under Grants DE-SC0006419 and DEFC02-99ER54512-CMOD.

  14. Development of site-specific locking plates for acetabular fractures.

    PubMed

    Xu, Meng; Zhang, Li-Hai; Zhang, Ying-Ze; He, Chun-Qing; Zhang, Li-Cheng; Wang, Yan; Tang, Pei-Fu

    2013-05-01

    Site-specific locking plates have gained popularity for the treatment of fractures. However, the clinical use of a site-specific locking plate for acetabular fractures remains untested due to production limits. To design a universal site-specific locking plate for acetabular fractures, the 3-dimensional (3D) photographic records of 171 pelvises were retrospectively studied to generate a universal posterior innominate bone surface. Using 3D photographical processing software, the 3D coordinate system was reset according to bony landmarks and was scaled based on the acetabular diameter to allow a direct comparison between surfaces. The measured surface was separated into measurement units. At each measurement unit, the authors calculated the average z-axis values in all samples and obtained the 3D coordinate values of the point cloud that could be reconstructed into the universal surface. A plate was subsequently designed in 3D photographical processing software, and the orientation and distribution of locking screws was included. To manufacture a plate, the data were entered into Unigraphics NX version 6.0 software (Siemens PLM Software, Co, Ltd, Plano, Texas) and a CNC digital milling machine (FANUC Co, Ltd, Yamanashi, Japan). The resulting locking plate fit excellently with the reduced bone surface intraoperatively. Plate contouring was avoided intraoperatively. Universal 3.5-mm locking screws locked successfully into the plate, and their orientations were consistent with the design. No screw yielded to acetabular penetration. This method of designing a site-specific acetabular locking plate is practical, and the plates are suitable for clinical use. These site-specific locking plates may be an option for the treatment of acetabular fractures, particularly in elderly patients.

  15. An analogue contact probe using a compact 3D optical sensor for micro/nano coordinate measuring machines

    NASA Astrophysics Data System (ADS)

    Li, Rui-Jun; Fan, Kuang-Chao; Miao, Jin-Wei; Huang, Qiang-Xian; Tao, Sheng; Gong, Er-min

    2014-09-01

    This paper presents a new analogue contact probe based on a compact 3D optical sensor with high precision. The sensor comprises an autocollimator and a polarizing Michelson interferometer, which can detect two angles and one displacement of the plane mirror at the same time. In this probe system, a tungsten stylus with a ruby tip-ball is attached to a floating plate, which is supported by four V-shape leaf springs fixed to the outer case. When a contact force is applied to the tip, the leaf springs will experience elastic deformation and the plane mirror mounted on the floating plate will be displaced. The force-motion characteristics of this probe were investigated and optimum parameters were obtained with the constraint of allowable physical size of the probe. Simulation results show that the probe is uniform in 3D and its contacting force gradient is within 1 mN µm - 1. Experimental results indicate that the probe has 1 nm resolution,  ± 10 µm measuring range in X - Y plane, 10 µm measuring range in Z direction and within 30 nm measuring standard deviation. The feasibility of the probe has been preliminarily verified by testing the flatness and step height of high precision gauge blocks.

  16. Temperature-stable parallel-plate dielectric cell for broadband liquid impedance measurements

    NASA Astrophysics Data System (ADS)

    Mazzeo, Brian A.; Chandra, Satyan; Mellor, Brett L.; Arellano, Jesus

    2010-12-01

    A liquid impedance cell for broadband impedance measurements up to 110 MHz is presented. The design incorporates temperature control and minimizes parasitic capacitance and inductance. The cell is simple to fabricate and uses chemically resistant materials, stainless steel, and Teflon. This dielectric cell can be used in a variety of liquid measurements, particularly those related to impedance measurements of biological objects in solution. Temperature control is illustrated in measurements of the permittivity of deionized water from 5 to 55 °C. Numerical fitting procedures employed on the relaxation curves indicate good agreement with previous studies on beta-lactoglobulin and hen lysozyme. Titration capability is demonstrated through dielectric titration of hen lysozyme and beta-lactoglobulin.

  17. On-machine measurement of the grinding wheels' 3D surface topography using a laser displacement sensor

    NASA Astrophysics Data System (ADS)

    Pan, Yongcheng; Zhao, Qingliang; Guo, Bing

    2014-08-01

    A method of non-contact, on-machine measurement of three dimensional surface topography of grinding wheels' whole surface was developed in this paper, focusing on an electroplated coarse-grained diamond grinding wheel. The measuring system consists of a Keyence laser displacement sensor, a Keyence controller and a NI PCI-6132 data acquisition card. A resolution of 0.1μm in vertical direction and 8μm in horizontal direction could be achieved. After processing the data by LabVIEW and MATLAB, the 3D topography of the grinding wheel's whole surface could be reconstructed. When comparing the reconstructed 3D topography of the grinding wheel's marked area to its real topography captured by a high-depth-field optical digital microscope (HDF-ODM) and scanning electron microscope (SEM), they were very similar to each other, proving that this method is accurate and effective. By a subsequent data processing, the topography of every grain could be extracted and then the active grain number, the active grain volume and the active grain's bearing ration could be calculated. These three parameters could serve as the criterion to evaluate the grinding performance of coarse-grained diamond grinding wheels. Then the performance of the grinding wheel could be evaluated on-machine accurately and quantitatively.

  18. Machine tool locator

    DOEpatents

    Hanlon, John A.; Gill, Timothy J.

    2001-01-01

    Machine tools can be accurately measured and positioned on manufacturing machines within very small tolerances by use of an autocollimator on a 3-axis mount on a manufacturing machine and positioned so as to focus on a reference tooling ball or a machine tool, a digital camera connected to the viewing end of the autocollimator, and a marker and measure generator for receiving digital images from the camera, then displaying or measuring distances between the projection reticle and the reference reticle on the monitoring screen, and relating the distances to the actual position of the autocollimator relative to the reference tooling ball. The images and measurements are used to set the position of the machine tool and to measure the size and shape of the machine tool tip, and examine cutting edge wear. patent

  19. Plate motion

    SciTech Connect

    Gordon, R.G. )

    1991-01-01

    The motion of tectonic plates on the earth is characterized in a critical review of U.S. research from the period 1987-1990. Topics addressed include the NUVEL-1 global model of current plate motions, diffuse plate boundaries and the oceanic lithosphere, the relation between plate motions and distributed deformations, accelerations and the steadiness of plate motions, the distribution of current Pacific-North America motion across western North America and its margin, plate reconstructions and their uncertainties, hotspots, and plate dynamics. A comprehensive bibliography is provided. 126 refs.

  20. Thickness measurement of transparent glass plates using a lateral shearing cyclic path optical configuration setup and polarization phase shifting interferometry.

    PubMed

    Kumar, Y Pavan; Chatterjee, Sanjib

    2010-11-20

    We present a measurement technique to determine the thickness of a transparent glass plate (GP) by using a lateral shearing cyclic path optical configuration (CPOC) setup and polarization phase shifting interferometry (PPSI). In the technique, the GP introduces a longitudinal shift in the focus of the beam and, as a result, a spherical wavefront emerges from the lens, which is otherwise set for producing a collimated beam. Using CPOC, two laterally sheared orthogonally polarized beams are generated from the incident spherical wavefront. By applying PPSI, the slope of the optical path difference variation between the laterally sheared interfering beams is evaluated, and the radius of the spherical wavefront and the longitudinal shift of the beam focus are calculated. The thickness of the GP is determined from the standard relation between the longitudinal shift of the focus introduced by the GP and the thickness of the GP. Results obtained for a GP of 9.810mm thickness are presented.

  1. Balanced Flow Measurement and Conditioning Technology (Balanced Orifice Plate 7,051,765 B1) for NASA Inventions and Contributions Board Invention of the Year Evaluation

    NASA Technical Reports Server (NTRS)

    Kelley, Anthony R.

    2008-01-01

    This viewgraph document reviews the Balanced Flow Measurement (BFM) and Conditioning Technology, and makes the case for this as the NASA Invention of the Year. The BFM technology makes use of a thin, multi-hole orifice plate with holes sized and placed per a unique set of equations. It produces mass flow, volumetric flow,kinelic energy,or momentum BALANCE across the face of the plate. The flow is proportional.to the square root of upstream to downstream differential pressure. Multiple holes lead to smoother pressure measurement. Measures and conditions or can limit fluid flow. This innovation has many uses in and out of NASA.

  2. Dynamic mode decomposition of separated flow over a finite blunt plate: time-resolved particle image velocimetry measurements

    NASA Astrophysics Data System (ADS)

    Liu, Yingzheng; Zhang, Qingshan

    2015-07-01

    events in the measurement region. The Karman vortex street was found to induce considerable localized movement of the fluid near the trailing edges of the plate. However, the leading-edge vortices near the trailing edge were found to detach away from the plate and fully decay around 0.5 D behind the trailing edge, where a well-ordered origination of the downstream large-scale vortical structures (the Karman vortex street) was established and might be locally energized by the decayed leading-edge vortex. In the longest system L/D = 9.0, the phase-dependent variations in the low-order flow disclosed a rapid decay of the leading-edge vortices beyond the reattachment zone, reaching the fully diffused state near the trailing edges. Accordingly, no clear signature of the interaction between the Karman vortex street and the leading-edge vortex could be found in the dynamic process of the leading-edge vortex.

  3. Strength of Rectangular Flat Plates Under Edge Compression

    NASA Technical Reports Server (NTRS)

    Schuman, Louis; Back, Goldie

    1931-01-01

    Flat rectangular plates of duralumin, stainless iron, monel metal, and nickel were tested under loads applied at two opposite edges and acting in the plane of the plate. The edges parallel to the direction of loading were supported in V grooves. The plates were all 24 inches long and varied in width from 4 to 24 inches by steps of 4 inches, and in thickness from 0.015 to 0.095 inch by steps of approximately 0.015 inch. There were also a few 1, 2, 3, and 6 inch wide specimens. The loads were applied in the testing machine at the center of a bar which rested along the top of the plate. Load was applied until the plate failed to take any more load. The tests show that the loads carried by the plates generally reached a maximum for the 8 or 12 inch width and that there was relatively small drop in load for the greater widths. Deflection and set measurement perpendicular to the plane of the plate were taken and the form of the buckle determined. The number of buckles were found to correspond in general to that predicted by the theory of buckling of a plate uniformly loaded at two opposite edges and simply supported at the edges.

  4. Experiment to Measure the Strength of Lead to ~ 1.5 Mbar by Compression and Release using the Z Machine

    NASA Astrophysics Data System (ADS)

    Rothman, Stephen; Brown, Justin; Davis, Jean-Paul

    2015-06-01

    We are planning an experiment to infer the strength of lead at ~ 1.5 Mbar by ramp compression and release using the Z machine. Longitudinal and bulk sound speeds may be calculated from the measurement of the velocity of the interface between thin lead samples and a LiF window by an iterative process using either a transfer-function or characteristics-based method to map in-situ velocity onto measured window velocity. The hydrostatic response comes from analysis of the compression; the strength at each iteration step from the difference between the longitudinal and (extrapolated) bulk sound speeds. As lead is expected to be soft, the effect of its strength on the expansion on release is thought to be small, and may be treated as an error on the results, contrary to similar results for, e.g., Ta. (c) British Crown Owned Copyright 2015/AWE.

  5. Compressive Sensing Based Machine Learning Strategy For Characterizing The Flow Around A Cylinder With Limited Pressure Measurements

    SciTech Connect

    Bright, Ido; Lin, Guang; Kutz, Nathan

    2013-12-05

    Compressive sensing is used to determine the flow characteristics around a cylinder (Reynolds number and pressure/flow field) from a sparse number of pressure measurements on the cylinder. Using a supervised machine learning strategy, library elements encoding the dimensionally reduced dynamics are computed for various Reynolds numbers. Convex L1 optimization is then used with a limited number of pressure measurements on the cylinder to reconstruct, or decode, the full pressure field and the resulting flow field around the cylinder. Aside from the highly turbulent regime (large Reynolds number) where only the Reynolds number can be identified, accurate reconstruction of the pressure field and Reynolds number is achieved. The proposed data-driven strategy thus achieves encoding of the fluid dynamics using the L2 norm, and robust decoding (flow field reconstruction) using the sparsity promoting L1 norm.

  6. Consistency of Field-Based Measures of Neuromuscular Control Using Force-Plate Diagnostics in Elite Male Youth Soccer Players.

    PubMed

    Read, Paul J; Oliver, Jon L; Croix, Mark Ba De Ste; Myer, Gregory D; Lloyd, Rhodri S

    2016-12-01

    Read, P, Oliver, JL, Croix, MD, Myer, GD, and Lloyd, RS. Consistency of field-based measures of neuromuscular control using force-plate diagnostics in elite male youth soccer players. J Strength Cond Res 30(12): 3304-3311, 2016-Deficits in neuromuscular control during movement patterns such as landing are suggested pathomechanics that underlie sport-related injury. A common mode of assessment is measurement of landing forces during jumping tasks; however, these measures have been used less frequently in male youth soccer players, and reliability data are sparse. The aim of this study was to examine the reliability of a field-based neuromuscular control screening battery using force-plate diagnostics in this cohort. Twenty-six pre-peak height velocity (PHV) and 25 post-PHV elite male youth soccer players completed a drop vertical jump (DVJ), single-leg 75% horizontal hop and stick (75%HOP), and single-leg countermovement jump (SLCMJ). Measures of peak landing vertical ground reaction force (pVGRF), time to stabilization, time to pVGRF, and pVGRF asymmetry were recorded. A test-retest design was used, and reliability statistics included change in mean, intraclass correlation coefficient, and coefficient of variation (CV). No significant differences in mean score were reported for any of the assessed variables between test sessions. In both groups, pVGRF and asymmetry during the 75%HOP and SLCMJ demonstrated largely acceptable reliability (CV ≤ 10%). Greater variability was evident in DVJ pVGRF and all other assessed variables, across the 3 protocols (CV range = 13.8-49.7%). Intraclass correlation coefficient values ranged from small to large and were generally higher in the post-PHV players. The results of this study suggest that pVGRF and asymmetry can be reliably assessed using a 75%HOP and SLCMJ in this cohort. These measures could be used to support a screening battery for elite male youth soccer players and for test-retest comparison.

  7. Nondestructive measurement of moisture content of different types of wheat using a single calibration with a parallel-plate capacitance sensor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A simple, low cost instrument that measures impedance and phase angle was used along with a parallel-plate capacitance system to estimate the moisture content (MC) of six types of wheat. Moisture content of grain is important and is measured at various stages of their processing and storage. A sampl...

  8. Measurements of the low wavenumber wall pressure spectral density during transition on a flat plate

    NASA Astrophysics Data System (ADS)

    Gedney, C. J.; Leehey, P.

    1984-04-01

    Experimental measurements of the low-Mach number wall pressure spectra density in the transition region are currently carried out in our laboratory. The six element (B&K Model No. 4144) microphone array used by Farabee and Geib was used as the wavenumber filtering apparatus and flush mounted on an open test section identical to that used by Jameson. A technique of conditional sampling on signals was used to determine the characteristics of the transitional flow. The frequency spectrum of the microphone array output was computed for uniform shading, Chebyshev shading and binomial shading. A detailed update on our progress is enclosed. The preliminary results indicate that there is no significant measurable difference in the low wavenumber wall pressure spectrum density for a transitional boundary layer as compared to a fully turbulent boundary layer.

  9. Validation of Multiple Tools for Flat Plate Photovoltaic Modeling Against Measured Data

    SciTech Connect

    Freeman, J.; Whitmore, J.; Blair, N.; Dobos, A. P.

    2014-08-01

    This report expands upon a previous work by the same authors, published in the 40th IEEE Photovoltaic Specialists conference. In this validation study, comprehensive analysis is performed on nine photovoltaic systems for which NREL could obtain detailed performance data and specifications, including three utility-scale systems and six commercial scale systems. Multiple photovoltaic performance modeling tools were used to model these nine systems, and the error of each tool was analyzed compared to quality-controlled measured performance data. This study shows that, excluding identified outliers, all tools achieve annual errors within +/-8% and hourly root mean squared errors less than 7% for all systems. It is further shown using SAM that module model and irradiance input choices can change the annual error with respect to measured data by as much as 6.6% for these nine systems, although all combinations examined still fall within an annual error range of +/-8.5%. Additionally, a seasonal variation in monthly error is shown for all tools. Finally, the effects of irradiance data uncertainty and the use of default loss assumptions on annual error are explored, and two approaches to reduce the error inherent in photovoltaic modeling are proposed.

  10. 1980 Volvo award in biomechanics. Measurement of the distribution of axial stress on the end-plate of the vertebral body.

    PubMed

    Horst, M; Brinckmann, P

    1981-01-01

    The distribution of axial stress on the end-plate of the vertebral body has been measured by the aid of miniature piezoelectric pressure transducers in specimens of motion segments of the human vertebral column. The results indicate that the stress distribution depends essentially on the state of degeneration of the intervertebral disc and on the relative position of the adjacent end-plates. Furthermore lumbar and thoracic motion segments show a different behaviour. The measured results relate to the problem of the stress dependent deformation of the growing vertebra, the codfish shape of the osteoporotic vertebra and to the mechanism of degeneration of the intervertebral disc.

  11. Inline Measurement of Particle Concentrations in Multicomponent Suspensions using Ultrasonic Sensor and Least Squares Support Vector Machines

    PubMed Central

    Zhan, Xiaobin; Jiang, Shulan; Yang, Yili; Liang, Jian; Shi, Tielin; Li, Xiwen

    2015-01-01

    This paper proposes an ultrasonic measurement system based on least squares support vector machines (LS-SVM) for inline measurement of particle concentrations in multicomponent suspensions. Firstly, the ultrasonic signals are analyzed and processed, and the optimal feature subset that contributes to the best model performance is selected based on the importance of features. Secondly, the LS-SVM model is tuned, trained and tested with different feature subsets to obtain the optimal model. In addition, a comparison is made between the partial least square (PLS) model and the LS-SVM model. Finally, the optimal LS-SVM model with the optimal feature subset is applied to inline measurement of particle concentrations in the mixing process. The results show that the proposed method is reliable and accurate for inline measuring the particle concentrations in multicomponent suspensions and the measurement accuracy is sufficiently high for industrial application. Furthermore, the proposed method is applicable to the modeling of the nonlinear system dynamically and provides a feasible way to monitor industrial processes. PMID:26393611

  12. An innovative method for coordinate measuring machine one-dimensional self-calibration with simplified experimental process.

    PubMed

    Fang, Cheng; Butler, David Lee

    2013-05-01

    In this paper, an innovative method for CMM (Coordinate Measuring Machine) self-calibration is proposed. In contrast to conventional CMM calibration that relies heavily on a high precision reference standard such as a laser interferometer, the proposed calibration method is based on a low-cost artefact which is fabricated with commercially available precision ball bearings. By optimizing the mathematical model and rearranging the data sampling positions, the experimental process and data analysis can be simplified. In mathematical expression, the samples can be minimized by eliminating the redundant equations among those configured by the experimental data array. The section lengths of the artefact are measured at arranged positions, with which an equation set can be configured to determine the measurement errors at the corresponding positions. With the proposed method, the equation set is short of one equation, which can be supplemented by either measuring the total length of the artefact with a higher-precision CMM or calibrating the single point error at the extreme position with a laser interferometer. In this paper, the latter is selected. With spline interpolation, the error compensation curve can be determined. To verify the proposed method, a simple calibration system was set up on a commercial CMM. Experimental results showed that with the error compensation curve uncertainty of the measurement can be reduced to 50%.

  13. 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.

  14. Advanced methodology for measuring the extensive elastic compliance and mechanical loss directly in k31 mode piezoelectric ceramic plates

    NASA Astrophysics Data System (ADS)

    Majzoubi, Maryam; Shekhani, Husain N.; Bansal, Anushka; Hennig, Eberhard; Scholehwar, Timo; Uchino, Kenji

    2016-12-01

    Dielectric, elastic, and piezoelectric constants, and their corresponding losses are defined under constant conditions of two categories; namely, intensive (i.e., E, electric field or T, stress), and extensive (i.e., D, dielectric displacement or x, strain) ones. So far, only the intensive parameters and losses could be measured directly in a k31 mode sample. Their corresponding extensive parameters could be calculated indirectly using the coupling factor and "K" matrix. However, the extensive loss parameters, calculated through this indirect method, could have large uncertainty, due to the error propagation in calculation. In order to overcome this issue, extensive losses should be measured separately from the measurable intensive ones in lead-zirconate-titanate (PZT) k31 mode rectangular plate ceramics. We propose a new mechanical-excitation methodology, using a non-destructive testing approach by means of a partial electrode configuration, instead of the conventional full electrode configuration. For this purpose, a non-electrode sample was prepared, where the electrode covered only 10% of the top and bottom surfaces at the center to actuate the whole sample, and also monitor the responding vibration. The admittance spectrum of this sample, corresponds to PZT properties under dielectric displacement D constant condition. Furthermore, ceramics with partial-electrodes were also prepared to create short and open circuit boundary conditions, attributing to resonance and anti-resonance modes. In the proposed way, we were able to measure both intensive and extensive elastic compliances and mechanical losses directly for the first time. The accuracy of this new method is compared with the conventional measurements by use of indirect calculations. The preliminary results (by neglecting the 10% actuator part difference at this point) were obtained, which were in good agreements (less than 3% difference) with the previous indirect method.

  15. Measurement of atmospheric air-earth current density from a tropical station using improvised Wilson's plate antenna

    NASA Astrophysics Data System (ADS)

    Anil Kumar, C. P.; Panneerselvam, C.; Nair, K. U.; Jeeva, K.; Selvaraj, C.; Johnson Jeyakumar, H.; Gurubaran, S.

    2009-07-01

    We have developed an experimental set-up to measure the atmospheric air-earth current (conduction current). Data obtained with the continuous measurements of Wilson's plate are used to study of air-earth current density, with the aim of gaining an understanding of the experimental set-up's response to different meteorological conditions, including fair-weather days. This paper is a part of the on-going Global Electric Circuit (GEC) studies from Tirunelveli (8.7°N, 77.8°E), a measurement site in the tropical and southern tip of the Indian peninsula. Attempts have been made in past few years to obtain the global signature in this region with this sensor, but on most of the occasions it has been impossible to obtain the global signature during fair-weather days. The data used for February-April, 2007 have the well-defined nature of this global signature, which is in agreement with the well-established classical Carnegie curve of GEC. This paper also deals with very important observations made at sunrise and during those hours when fog existed. It is noted that the resistivity of the atmosphere increased significantly with the onset of fog and later decreased as the fog disappeared, based on the measured value of conduction current density when compared with the electric field measured by horizontal passive wire antenna. Also, during fair-weather conditions, conduction current and electric field variations are similar because the conductivity during this period is more or less constant at this site. Observations made during different meteorological conditions, such as different wind speeds, humidities, and temperatures, are also discussed.

  16. A human CXCL13-induced actin polymerization assay measured by fluorescence plate reader.

    PubMed

    Alley, Jennifer; Bloom, Laird; Kasaian, Marion; Gao, Huilan; Berstein, Gabriel; Clark, James D; Miao, Wenyan

    2010-02-01

    The chemokine receptor CXCR5 is predominantly expressed on mature B cells and follicular T-helper cells. CXCR5 and its ligand CXCL13 participate in ectopic germinal center formation at the inflammatory sites of multiple immune diseases such as rheumatoid arthritis, multiple sclerosis, and Sjogren's syndrome. Therefore, disrupting CXCL13-induced chemotaxis may be a fruitful approach for developing therapeutics in treating these diseases. Cells undergo cytoskeletal rearrangement prior to chemotaxis, and therefore actin polymerization can be used as a surrogate readout more proximal to chemokine receptor activation than chemotaxis. Conventionally, actin polymerization is measured by fluorescence microscopy or flow cytometry, which are either of low throughput or in need of special instruments. We developed a 96-well actin polymerization assay that can process 1,000 to 1,500 samples a day. This assay uses a standard laboratory fluorescence microplate reader as the detection instrument and was optimized for various experimental conditions such as cell density, actin filament staining reagent, staining buffer, and cell culture conditions. We demonstrate that this actin polymerization assay in 96-well format exhibits the expected pharmacology for human CXCR5 and is suitable as a primary functional assay to screen neutralizing scFv in crude bacterial peri-preps and a secondary assay for small compound collections.

  17. Damage detection in plates using the electromechanical impedance technique based on decoupled measurements of piezoelectric transducers

    NASA Astrophysics Data System (ADS)

    Tinoco, Hector A.; Robledo-Callejas, Leonardo; Marulanda, Dairon J.; Serpa, Alberto L.

    2016-12-01

    Electromechanical impedance (EMI) technique plays an important role in the monitoring of structures with piezoelectric transducers (PT). According to the EMI technique, diagnosis and prognosis can be carried out to detect structural modifications in an operative state. However, to develop an efficient methodology for damage detection; damage metrics and patterns should be defined using indices to quantify changes in the signals. In this study, a new approach is proposed considering the electrical impedance (EI) of PT as an array of coupled electrical impedances. It means that when a PT is bonded to a structure, the EI is governed by an electrical circuit that is assumed to be parallel and composed by electrical contributions of both, the structure and the PT. In our perspective, each free PT presents unique mechanical characteristics and those differences may influence the measured electrical signals, therefore the electrical contributions generated by each piezo-transducer are taken into account. To evaluate the electrical decoupling, two methodologies of damage detection are proposed to identify and locate an induced damage. In these methodologies, the damage metrics are based on ellipses of Gaussian confidence. Four experimental tests were performed to evaluate the methodologies, applying two damage intensities. The results show that the partial process of identification of a damage type is a feasible and applicable procedure, moreover the proposed method was able to evidence the damage location..

  18. A Machine Learning Approach to Measurement of Text Readability for EFL Learners Using Various Linguistic Features

    ERIC Educational Resources Information Center

    Kotani, Katsunori; Yoshimi, Takehiko; Isahara, Hitoshi

    2011-01-01

    The present paper introduces and evaluates a readability measurement method designed for learners of EFL (English as a foreign language). The proposed readability measurement method (a regression model) estimates the text readability based on linguistic features, such as lexical, syntactic and discourse features. Text readability refers to the…

  19. Machine Shop Grinding Machines.

    ERIC Educational Resources Information Center

    Dunn, James

    This curriculum manual is one in a series of machine shop curriculum manuals intended for use in full-time secondary and postsecondary classes, as well as part-time adult classes. The curriculum can also be adapted to open-entry, open-exit programs. Its purpose is to equip students with basic knowledge and skills that will enable them to enter the…

  20. Evaluation of the efficiency and effectiveness of independent dose calculation followed by machine log file analysis against conventional measurement based IMRT QA.

    PubMed

    Sun, Baozhou; Rangaraj, Dharanipathy; Boddu, Sunita; Goddu, Murty; Yang, Deshan; Palaniswaamy, Geethpriya; Yaddanapudi, Sridhar; Wooten, Omar; Mutic, Sasa

    2012-09-06

    Experimental methods are commonly used for patient-specific IMRT delivery verification. There are a variety of IMRT QA techniques which have been proposed and clinically used with a common understanding that not one single method can detect all possible errors. The aim of this work was to compare the efficiency and effectiveness of independent dose calculation followed by machine log file analysis to conventional measurement-based methods in detecting errors in IMRT delivery. Sixteen IMRT treatment plans (5 head-and-neck, 3 rectum, 3 breast, and 5 prostate plans) created with a commercial treatment planning system (TPS) were recalculated on a QA phantom. All treatment plans underwent ion chamber (IC) and 2D diode array measurements. The same set of plans was also recomputed with another commercial treatment planning system and the two sets of calculations were compared. The deviations between dosimetric measurements and independent dose calculation were evaluated. The comparisons included evaluations of DVHs and point doses calculated by the two TPS systems. Machine log files were captured during pretreatment composite point dose measurements and analyzed to verify data transfer and performance of the delivery machine. Average deviation between IC measurements and point dose calculations with the two TPSs for head-and-neck plans were 1.2 ± 1.3% and 1.4 ± 1.6%, respectively. For 2D diode array measurements, the mean gamma value with 3% dose difference and 3 mm distance-to-agreement was within 1.5% for 13 of 16 plans. The mean 3D dose differences calculated from two TPSs were within 3% for head-and-neck cases and within 2% for other plans. The machine log file analysis showed that the gantry angle, jaw position, collimator angle, and MUs were consistent as planned, and maximal MLC position error was less than 0.5 mm. The independent dose calculation followed by the machine log analysis takes an average 47 ± 6 minutes, while the experimental approach (using IC and

  1. Flow-Field Measurement of Device-Induced Embedded Streamwise Vortex on a Flat Plate

    NASA Technical Reports Server (NTRS)

    Yao, Chung-Sheng; Lin, John C.; Allan, Brian G.

    2002-01-01

    Detailed flow-field measurements were performed downstream of a single vortex generator (VG) using an advanced Stereo Digital Particle Image Velocimetry system. Thc passive flow-control devices examined consisted of a low-profile VG with a device height, h, approximately equal to 20 percent of the boundary-layer thickness, sigma, and a conventional VG with h is approximately sigma. Flow-field data were taken at twelve cross-flow planes downstream of the VG to document and quantify the evolution of embedded streamwise vortex. The effects of device angle of attack on vortex development downstream were compared between the low-profile VG and the conventional VG. Key parameters including vorticity, circulation, trajectory, and half-life radius - describing concentration, strength, path, and size, respectively--of the device-induced streamwise vortex were extracted from the flow-field data. The magnitude of maximum vorticity increases as angle of attack increases for the low-profile VG, but the trend is reversed for the conventional VG, probably due to flow stalling around the larger device at higher angles of attack. Peak vorticity and circulation for the low-profile VG decays exponentially and inversely proportional to the distance downstream from the device. The device-height normalized vortex trajectories for the low-profile VG, especially in the lateral direction, follow the general trends of the conventional VG. The experimental database was used to validate the predictive capability of computational fluid dynamics (CFD). CFD accurately predicts the vortex circulation and path; however, improvements are needed for predicting the vorticity strength and vortex size.

  2. Machine vision approach for improving accuracy of focus-based depth measurements

    NASA Astrophysics Data System (ADS)

    Bryll, Robert

    2008-02-01

    Focus-based depth (Z) measurements are used extensively in industrial metrology and microscopy. Typically, a peak in the focus figure-of-merit of a region is found while moving the lens towards or away from the surface, allowing local recovery of depth. These focus-based measurements are susceptible to errors caused by: (1) Optical aberrations and characteristics of the lens (astigmatism, field curvature); (2) Optical and image sensor misalignments; (3) Image sensor shape errors. Depth measurements of the same artifact can therefore significantly vary depending on the prevailing orientation of the surface texture (due to lens astigmatism) or on the specific position in the field of view. We present a vision-based algorithm to reduce errors in focus-based depth measurements. The algorithm consists of two steps: 1. Offline calibration: We generate a calibration table for the optical system, consisting of a set of Z calibration curves for different locations in the field of view. 2. Run-time correction: During measurement, we determine the Z correction to the focus position using the stored Z calibration curves and a measurement of the local orientation of the surface texture. In our tests, the correction algorithm reduced the depth measurement errors by a factor of 2, on average, for a wide range of surfaces and conditions.

  3. Measurements of neutron distribution in neutrons-gamma-rays mixed field using imaging plate for neutron capture therapy.

    PubMed

    Tanaka, Kenichi; Endo, Satoru; Hoshi, Masaharu

    2010-01-01

    The imaging plate (IP) technique is tried to be used as a handy method to measure the spatial neutron distribution via the (157)Gd(n,gamma)(158)Gd reaction for neutron capture therapy (NCT). For this purpose, IP is set in a water phantom and irradiated in a mixed field of neutrons and gamma-rays. The Hiroshima University Radiobiological Research Accelerator is utilized for this experiment. The neutrons are moderated with 20-cm-thick D(2)O to obtain suitable neutron field for NCT. The signal for IP doped with Gd as a neutron-response enhancer is subtracted with its contribution by gamma-rays, which was estimated using IP without Gd. The gamma-ray response of Gd-doped IP to non-Gd IP is set at 1.34, the value measured for (60)Co gamma-rays, in estimating the gamma-ray contribution to Gd-doped IP signal. Then measured distribution of the (157)Gd(n,gamma)(158)Gd reaction rate agrees within 10% with the calculated value based on the method that has already been validated for its reproducibility of Au activation. However, the evaluated distribution of the (157)Gd(n,gamma)(158)Gd reaction rate is so sensitive to gamma-ray energy, e.g. the discrepancy of the (157)Gd(n,gamma)(158)Gd reaction rate between measurement and calculation becomes 30% for the photon energy change from 33keV to 1.253MeV.

  4. Grain-boundary sliding measurements in Al[sub 2]O[sub 3] by machine vision photogrammetry

    SciTech Connect

    Blanchard, C.R.; Page, R.A. )

    1991-01-01

    The nucleation, growth and coalescence of grain-boundary cavities is the primary damage mechanism observed during creep of structural ceramics. Furthermore, grain-boundary sliding (GBS) has been identified as the driving force process. Although the creep characteristics of structural ceramics have been extensively studied, very little is known about the details of GBS during creep and how GBS relates to cavitation kinetics. This paper presents the results of a study using a machine vision system to measure Mode 2 GBS displacements in a Lucalox Al[sub 2]O[sub 3]. Specifically, sliding displacements as large as 0.4 [mu]m were measured. The measured displacements indicate that some grain boundaries experienced shear strains and strain rates of 4,200% and 2.3 [times] 10[sup [minus]2]s[sup [minus]1], respectively. The techniques utilized for these measurements are described in detail, and data gathered during a 2 1/2 h compressive creep test under a stress of 138 MPa at 1,600 C are presented and discussed.

  5. Fabrication of electroless nickel plated aluminum freeform mirror for an infrared off-axis telescope.

    PubMed

    Kim, Sanghyuk; Chang, Seunghyuk; Pak, Soojong; Lee, Kwang Jo; Jeong, Byeongjoon; Lee, Gil-jae; Kim, Geon Hee; Shin, Sang Kyo; Yoo, Song Min

    2015-12-01

    Freeform mirrors can be readily fabricated by a single point diamond turning (SPDT) machine. However, this machining process often leaves mid-frequency errors (MFEs) that generate undesirable diffraction effects and stray light. In this work, we propose a novel thin electroless nickel plating procedure to remove MFE on freeform surfaces. The proposed procedure has a distinct advantage over a typical thick plating method in that the machining process can be endlessly repeated until the designed mirror surface is obtained. This is of great importance because the sophisticated surface of a freeform mirror cannot be optimized by a typical SPDT machining process, which can be repeated only several times before the limited thickness of the nickel plating is consumed. We will also describe the baking process of a plated mirror to improve the hardness of the mirror surface, which is crucial for minimizing the degradation of that mirror surface that occurs during the polishing process. During the whole proposed process, the changes in surface figures and textures are monitored and cross checked by two different types of measurements, as well as by an interference pattern test. The experimental results indicate that the proposed thin electroless nickel plating procedure is very simple but powerful for removing MFEs on freeform mirror surfaces.

  6. Experimental studies on the tripping behavior of narrow T-stiffened flat plates subjected to hydrostatic pressure and underwater shock

    NASA Technical Reports Server (NTRS)

    Budweg, H. L.; Shin, Y. S.

    1987-01-01

    An experimental investigation was conducted to determine the static and dynamic responses of a specific stiffened flat plate design. The air-backed rectangular flat plates of 6061-T6 aluminum with an externally machined longitudinal narrow-flanged T-stiffener and clamped boundary conditions were subjected to static loading by water hydropump pressure and shock loading from an eight pound TNT charge detonated underwater. The dynamic test plate was instrumented to measure transient strains and free field pressure. The static test plate was instrumented to measure transient strains, plate deflection, and pressure. Emphasis was placed upon forcing static and dynamic stiffener tripping, obtaining relevant strain and pressure data, and studying the associated plate-stiffener behavior.

  7. Macular pigment and lens optical density measurements-evaluating a flicker machine with novel features

    NASA Astrophysics Data System (ADS)

    Mukherjee, Anirbaan

    Age related macular degeneration (AMD) is one of the leading causes of blindness amongst the elderly. Macular pigment (MP) in the retina has been established to protect individuals against AMD. Improving levels of MP by diet or supplements is the constant quest of clinical practitioners and researchers, thus necessitating development of instruments capable of repeatable and reliable MP measurement. Cataract, a consequence of the rising opacity levels of the lens with age is one of the other major causes of blindness in the world. Mapcatsf, a LED-based microprocessor-controlled heterochromatic flicker photometer (HFP) using photopic vision is capable of measuring the levels of MP and the opacity of the lens in terms of optical density. Test-retest measurements conducted on 83 subjects were analyzed for repeatability in macular pigment optical density (MPOD) measurements. Reliability of the lens optical density (LOD) measurements were tested and compared with those obtained at absolute scotopic thresholds for 25 individuals. A supplement study with 32 individuals both in the young (50) age groups for 6 months further established Mapcatsf's capacity to monitor changing levels of MP in individuals. As an overall outcome, high levels of repeatability and reliability were obtained in MPOD and LOD measurements establishing Mapcatsf as an instrument for use in clinical settings in the future.

  8. Real-time electron density measurements from Cotton-Mouton effect in JET machine

    SciTech Connect

    Brombin, M.; Boboc, A.; Zabeo, L.

    2008-10-15

    Real-time density profile measurements are essential for advanced fusion tokamak operation and interferometry is a proven method for this task. Nevertheless, as a consequence of edge localized modes, pellet injections, fast density increases, or disruptions, the interferometer is subject to fringe jumps, which produce loss of the signal preventing reliable use of the measured density in a real-time feedback controller. An alternative method to measure the density is polarimetry based on the Cotton-Mouton effect, which is proportional to the line-integrated electron density. A new analysis approach has been implemented and tested to verify the reliability of the Cotton-Mouton measurements for a wide range of plasma parameters and to compare the density evaluated from polarimetry with that from interferometry. The density measurements based on polarimetry are going to be integrated in the real-time control system of JET since the difference with the interferometry is within one fringe for more than 90% of the cases.

  9. Real-time electron density measurements from Cotton-Mouton effect in JET machine.

    PubMed

    Brombin, M; Boboc, A; Zabeo, L; Murari, A

    2008-10-01

    Real-time density profile measurements are essential for advanced fusion tokamak operation and interferometry is a proven method for this task. Nevertheless, as a consequence of edge localized modes, pellet injections, fast density increases, or disruptions, the interferometer is subject to fringe jumps, which produce loss of the signal preventing reliable use of the measured density in a real-time feedback controller. An alternative method to measure the density is polarimetry based on the Cotton-Mouton effect, which is proportional to the line-integrated electron density. A new analysis approach has been implemented and tested to verify the reliability of the Cotton-Mouton measurements for a wide range of plasma parameters and to compare the density evaluated from polarimetry with that from interferometry. The density measurements based on polarimetry are going to be integrated in the real-time control system of JET since the difference with the interferometry is within one fringe for more than 90% of the cases.

  10. CAR MACHINE SHOP, SECOND FLOOR, LYE TANKS FOR CLEANING METAL ...

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

    CAR MACHINE SHOP, SECOND FLOOR, LYE TANKS FOR CLEANING METAL PRIOR TO PLATING, LOOKING SOUTH FROM ATTIC. - Southern Pacific, Sacramento Shops, Car Machine Shop, 111 I Street, Sacramento, Sacramento County, CA

  11. CAR MACHINE SHOP, SECOND FLOOR, LYE TANKS FOR CLEANING METAL ...

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

    CAR MACHINE SHOP, SECOND FLOOR, LYE TANKS FOR CLEANING METAL PRIOR TO PLATING, LOOKING SOUTHWEST FROM ATTIC. - Southern Pacific, Sacramento Shops, Car Machine Shop, 111 I Street, Sacramento, Sacramento County, CA

  12. A machine vision-based method of high-precision measurement of the size of workpiece

    NASA Astrophysics Data System (ADS)

    Jia, Xiyuan; Guo, Tiantai; Zhao, Jun; Kong, Ming; Lu, Shouchuang; Shen, Yong

    2016-01-01

    The posture and size of workpiece in pixel level can be determined through optimization of the internal parameters of the camera, utilizing the enclosing rectangle method based on rotation axis to position the workpiece. After selecting ROI of the object, the sub-pixel edge of workpiece is extracted using the bilinear interpolation algorithm and Hessian paradigm line fitting is utilized to find the object edge accurately. The industrial camera with 5 million pixels is used, and the sizes from 80mm to 150mm of the workpiece are measured under the condition of panorama shooting, with measurement repeatability reaching 0.015mm.

  13. Partially light-controlled imager based on liquid crystal plate and image intensifier for aurora and airglow measurement.

    PubMed

    Tang, Yuanhe; Cao, Xiangang; Liu, Hanchen; Shepherd, G G; Liu, Shulin; Gao, Haiyang; Yang, Xusan; Wu, Yong; Wang, Shuiwei

    2012-04-20

    In order to obtain information both of aurora and airglow in one image by the same detector, a PLCI based on liquid crystal plate LCP and super second-generation image intensifier SSGII is proposed in this research. The detection thresholds of the CCD for aurora and airglow are calculated. For the detectable illumination range of 10(4)-10(-2) lx, the corresponding electron count is 1.57×10(5) - 0.2 for every pixel of CCD. The structure and work principle of the PLCI are described. An LC is introduced in the front of CCD to decrease the intensities of aurora in overexposure areas by means of controlling transmittances pixel by pixel, while an image intensifier is set between the LC and CCD to increase the intensity of the weak airglow. The modulation transfer function MTF of this system is calculated as 0.391 at a Nyquist frequency of 15 lp/mm. The curve of transmittance with regard to gray level for the LC is obtained by calibration experiment. Based on the design principle, the prototype is made and used to take photos of objects under strong light greater than 2×10(5) lx. The clear details of [symbols: see text] presented in the image indicate that the PLCI can greatly improve the imaging quality. The theoretical calculations and experiment results prove that this device can extend the dynamic range and it provides a more effective method for upper atmospheric wind measurement.

  14. Stress and strain relaxation in magnesium AZ31 rolled plate: In-situ neutron measurement and elastic viscoplastic polycrystal modeling

    DOE PAGES

    Wang, Huamiao; Clausen, Bjorn; Capolungo, Laurent; ...

    2015-07-16

    Continuous mechanical tests with strain holds (stress relaxation) and with stress holds (strain relaxation) are performed simultaneously with in-situ neutron measurements to analyze the mechanisms of stress and strain relaxation in Mg AZ31 rolled plate. A dislocation activity based constitutive model, accounting for internal stress statistical distributions, is proposed and implemented into an elastic viscoplastic self-consistent (EVPSC) framework to simultaneously describe both stress and strain relaxation. The model captures the experimental data in terms of macroscopic stress strain curves, evolution of stress and strain during holding, as well as evolution of the internal elastic strains. Model results indicate that themore » magnitude of the stress relaxed during strain holding is dependent on both, the magnitude of the flow stress and the spread of the resolved shear stress distribution. The magnitude of strain accumulated during stress holding is, on the other hand, dependent on the magnitude of the hardening rate and on the spread of the resolved shear stress distribution. Furthermore, the internal elastic strains are directly correlated with the stress state, and hence the stress relaxation during strain holds has a greater influence on the lattice strains than strain relaxation during stress holds.« less

  15. Dose profile measurement using an imaging plate: Evaluation of filters using Monte Carlo simulation of 4 MV x-rays.

    PubMed

    Hashimoto, Masatoshi; Tomita, Tetsuya; Sawada, Koichi; Fujibuchi, Toshioh; Nishio, Teiji; Nakagawa, Keiichi

    2009-04-01

    Computed radiography (CR) is gradually replacing film. The application of CR for two-dimensional profiles and off-axis ratio (OAR) measurement using an imaging plate (IP) in a CR system is currently under discussion. However, a well known problem for IPs in dosimetry is that they use high atomic number (Z) materials, such as Ba, which have an energy dependency in a photon interaction. Although there are some reports that it is possible to compensate for the energy dependency with metal filters, the appropriate thicknesses of these filters and where they should be located have not been investigated. The purpose of this study is to find the most suitable filter for use with an IP as a dosimetric tool. Monte Carlo simulation (Geant4 8.1) was used to determine the filter to minimize the measurement error in OAR measurements of 4 MV x-rays. In this simulation, the material and thickness of the filter and distance between the IP and the filter were varied to determine most suitable filter conditions that gave the best fit to the MC calculated OAR in water. With regard to changing the filter material, we found that using higher Z and higher density material increased the effectiveness of the filter. Also, increasing the distance between the filter and the IP reduced the effectiveness, whereas increasing the thickness of the filter increased the effectiveness. The result of this study showed that the most appropriate filter conditions consistent with the calculated OAR in water were the ones with the IP sandwiched between two 2 mm thick lead filters at a distance of 5 mm from the IP or the IP sandwiched directly between two 1 mm lead filters. Using these filters, we measured the OAR at 10 cm depth with 100 cm source-to-surface distance and surface 10x10 cm(2) field size. The results of this measurement represented that it is possible to achieve measurements with less than within 2.0% and 2.0% in the field and with less than 1.1% and 0.6% out of the field by using 2 and 1

  16. Performance Measurement for Brain-Computer or Brain-Machine Interfaces: A Tutorial

    PubMed Central

    Thompson, David E.; Quitadamo, Lucia R.; Mainardi, Luca; Laghari, Khalil ur Rehman; Gao, Shangkai; Kindermans, Pieter-Jan; Simeral, John D.; Fazel-Rezai, Reza; Matteucci, Matteo; Falk, Tiago H.; Bianchi, Luigi; Chestek, Cynthia A.; Huggins, Jane E.

    2014-01-01

    Objective Brain-Computer Interfaces (BCIs) have the potential to be valuable clinical tools. However, the varied nature of BCIs, combined with the large number of laboratories participating in BCI research, makes uniform performance reporting difficult. To address this situation, we present a tutorial on performance measurement in BCI research. Approach A workshop on this topic was held at the 2013 International BCI Meeting at Asilomar Conference Center in Pacific Grove, California. This manuscript contains the consensus opinion of the workshop members, refined through discussion in the following months and the input of authors who were unable to attend the workshop. Main Results Checklists for methods reporting were developed for both discrete and continuous BCIs. Relevant metrics are reviewed for different types of BCI research, with notes on their application to encourage uniform application between laboratories. Significance Graduate students and other researchers new to BCI research may find this tutorial a helpful introduction to performance measurement in the field. PMID:24838070

  17. The propagation characteristics of the plate modes of acoustic emission waves in thin aluminum plates and thin graphite/epoxy composite plates and tubes. Ph.D. Thesis - Johns Hopkins Univ., 1991

    NASA Technical Reports Server (NTRS)

    Prosser, William H.

    1991-01-01

    Acoustic emission was interpreted as modes of vibration in plates. Classical plate theory was used to predict dispersion curves for the two fundamental modes and to calculate the shapes of flexural waveforms produced by vertical step function loading. There was good agreement between theoretical and experimental results for aluminum. Composite materials required the use of a higher order plate theory (Reissner-Mindlin) to get good agreement with the measured velocities. Four composite plates with different laminate stacking sequences were studied. The dispersion curves were determined from phase spectra of the time dependent waveforms. Plate modes were shown to be useful for determining the direction of source motion. Aluminum plates were loaded by breaking a pencil lead against their surface. By machining slots at angles to the plane of a plate, the direction in which the force acted was varied. Changing the source motion direction produced regular variations in the waveforms. To demonstrate applicability beyond simple plates, waveforms produced by lead breaks on a thin walled composite tube were also shown to be interpretable as plate modes. The tube design was based on the type of struts proposed for Space Station Freedom's trussed structures.

  18. Neutron diffraction measurement of residual stresses, dislocation density and texture in Zr-bonded U-10Mo "mini" fuel foils and plates

    NASA Astrophysics Data System (ADS)

    Brown, D. W.; Okuniewski, M. A.; Sisneros, T. A.; Clausen, B.; Moore, G. A.; Balogh, L.

    2016-12-01

    Al clad U-10Mo fuel plates are being considered for conversion of several research reactors from high-enriched to low-enriched U fuel. Neutron diffraction measurements of the textures, residual phase stresses, and dislocation densities in the individual phases of the mini-foils throughout several processing steps and following hot-isostatic pressing to the Al cladding, have been completed. Recovery and recrystallization of the bare U-10Mo fuel foil, as indicated by the dislocation density and texture, are observed depending on the state of the material prior to annealing and the duration and temperature of the annealing process. In general, the cladding procedure significantly reduces the dislocation density, but the final state of the clad plate, both texture and dislocation density, depends strongly on the final processing step of the fuel foil. In contrast, the residual stress state of the final plate is dominated by the thermal expansion mismatch of the constituent materials.

  19. Neutron diffraction measurement of residual stresses, dislocation density and texture in Zr-bonded U-10Mo “mini” fuel foils and plates

    SciTech Connect

    Brown, Donald William; Okuniewski, Maria A.; Sisneros, Thomas A.; Clausen, Bjorn; Moore, Glenn A.; Balogh, Levente

    2016-12-01

    Here, Al clad U-10Mo fuel plates are being considered for conversion of several research reactors from high-enriched to low-enriched U fuel. Neutron diffraction measurements of the textures, residual phase stresses, and dislocation densities in the individual phases of the mini-foils throughout several processing steps and following hot-isostatic pressing to the Al cladding, have been completed. Recovery and recrystallization of the bare U-10Mo fuel foil, as indicated by the dislocation density and texture, are observed depending on the state of the material prior to annealing and the duration and temperature of the annealing process. In general, the cladding procedure significantly reduces the dislocation density, but the final state of the clad plate, both texture and dislocation density, depends strongly on the final processing step of the fuel foil. In contrast, the residual stress state of the final plate is dominated by the thermal expansion mismatch of the constituent materials.

  20. Systematic measurements of whole-body dose distributions for various treatment machines and delivery techniques in radiation therapy

    SciTech Connect

    Haelg, Roger A.; Besserer, Juergen; Schneider, Uwe

    2012-12-15

    Purpose: Contemporary radiotherapy treatment techniques, such as intensity-modulated radiation therapy and volumetric modulated arc therapy, could increase the radiation-induced malignancies because of the increased beam-on time, i.e., number of monitor units needed to deliver the same dose to the target and the larger volume irradiated with low doses. In this study, whole-body dose distributions from typical radiotherapy patient plans using different treatment techniques and therapy machines were measured using the same measurement setup and irradiation intention. Methods: Individually calibrated thermoluminescent dosimeters were used to measure absorbed dose in an anthropomorphic phantom at 184 locations. The dose distributions from 6 MV beams were compared in terms of treatment technique (3D-conformal, intensity-modulated radiation therapy, volumetric modulated arc therapy, helical TomoTherapy, stereotactic radiotherapy, hard wedges, and flattening filter-free radiotherapy) and therapy machine (Elekta, Siemens and Varian linear accelerators, Accuray CyberKnife and TomoTherapy). Results: Close to the target, the doses from intensity-modulated treatments (including flattening filter-free) were below the dose from a static treatment plan, whereas the CyberKnife showed a larger dose by a factor of two. Far away from the treatment field, the dose from intensity-modulated treatments showed an increase in dose from stray radiation of about 50% compared to the 3D-conformal treatment. For the flattening filter-free photon beams, the dose from stray radiation far away from the target was slightly lower than the dose from a static treatment. The CyberKnife irradiation and the treatment using hard wedges increased the dose from stray radiation by nearly a factor of three compared to the 3D-conformal treatment. Conclusions: This study showed that the dose outside of the treated volume is influenced by several sources. Therefore, when comparing different treatment techniques

  1. A biomechanical comparison of three different lateral tibia locking plates.

    PubMed

    Lindeque, Bennie; Baldini, Todd

    2010-01-01

    The purpose of this study was to determine how well laterally placed modern tibia locking plates used in the treatment of Schatzker V tibial plateau fractures would uphold the medial plateau during axial loading. Fifteen third generation Sawbone tibias were obtained and an osteotomy was cut beneath the medial plateau to recreate Schatzker V type plateau fractures. Three groups were created (n=5 per group). Each group was plated with either a Synthes 4.5-mm LCP proximal tibial plate, a Zimmer NCB proximal tibia plate, or a DePuy Polyax tibial plate. A vertical load was applied over the medial plateau using an Instron servohydraulic test machine. Load measurements were analyzed at 2 and 3 mm of subsidence as well as load to failure. Failure was defined as closure of the wedge osteotomy or the medial condyle collapsing. A statistical difference was noted between the 2 plates from Synthes and DePuy and the plate from Zimmer with load carried at 2 and 3 mm of subsidence (Synthes 640.4 N & 943.7 N, Depuy 607.4 N & 891.0 N, Zimmer 459.7 N & 643.2 N). At failure, DePuy (2051.2 N) was statistically stronger than both Synthes (1724.8 N) and Zimmer (1724.8 N). The Synthes and DePuy plates both held up better than the Zimmer plate at 2 and 3 mm of subsidence. Despite this fact, all plates tested held up well above physiological forces of full and partial weight bearing and therefore would be appropriate for the treatment of Schatzker V type tibial plateau fractures.

  2. Design of divertor plate and measurements of double-null open divertor plasma in the JFT-2M tokamak

    NASA Astrophysics Data System (ADS)

    Yanagisawa, Ichiro; Shoji, Teruaki; Mori, Masahiro; Odajima, Kazuo; Ohtsuka, Hideo; Suzuki, Norio; Hasegawa, Mitsuru; Ohta, Kanji; Sugihara, Masayoshi; Uesugi, Yoshihiko

    1987-10-01

    The Design of the divertor plate, the results of the computational simulation and the experimental results on the compact diverter of the JFT-2 tokamak are described. Graphite divertor plates have showed a good performance as divertor target materials through divertor discharges. The H-mode plasma and low temperature, high density divertor plasma are obtained. From computational results, this is in the intermediate region between low and high recycling region.

  3. Measurement of LiNbO3 Rectangular Plate Under Large Vibration Velocity of the First Longitudinal and Second Flexural Modes

    NASA Astrophysics Data System (ADS)

    Tamura, Hideki; Iwase, Masashi; Hirose, Seiji; Aoyagi, Manabu; Takano, Takehiro; Tomikawa, Yoshiro

    2008-05-01

    We have studied a miniature ultrasonic motor using a piezoelectric single-crystal LiNbO3. The crystal vibrator retains superior characteristics even when the vibrational velocity is large. On the other hand, a vibrator using a resonance mode shows no signs of an operating limit and fractures itself when the vibrational velocity exceeds the limit. Such behavior causes a problem in controlling the achievement of a large output power from the motor. Therefore we must investigate the vibrational characteristics at a high vibration level and at the fracture limit. In this study, the samples were examined for their vibrational characteristics at a high driving level and at the fracture limit. First, the characteristics of the resonance vibration of the first longitudinal and second flexural modes in an X128°-rotated Y-cut rectangular plate were measured. Second, to evaluate the difference caused by the cut angle of the X-rotation, the characteristics for the first longitudinal mode of X128°-, X135°-, X140°- and X155°-rotated Y-plates were measured; additionally, for each rotation-angle plate, we measured the characteristics of the rectangular plates whose longer side was directed along the x- or z‧-axis. In this paper, we describe the experimental results for the high-power characteristics and the fracture limits.

  4. Improved Methods for Teaching Machine Transcription.

    ERIC Educational Resources Information Center

    Smith, Clara J.

    1980-01-01

    The increased use of machine transcription in business and industry demands that business educators attract and train more highly skilled machine transcriptionists. Realistic production measurement and appropriate vocabulary should be taught to link machine transcription to word processing. (Author)

  5. A Machine-learning Approach to Measuring the Escape of Ionizing Radiation from Galaxies in the Reionization Epoch

    NASA Astrophysics Data System (ADS)

    Jensen, Hannes; Zackrisson, Erik; Pelckmans, Kristiaan; Binggeli, Christian; Ausmees, Kristiina; Lundholm, Ulrika

    2016-08-01

    Recent observations of galaxies at z≳ 7, along with the low value of the electron scattering optical depth measured by the Planck mission, make galaxies plausible as dominant sources of ionizing photons during the epoch of reionization. However, scenarios of galaxy-driven reionization hinge on the assumption that the average escape fraction of ionizing photons is significantly higher for galaxies in the reionization epoch than in the local universe. The NIRSpec instrument on the James Webb Space Telescope (JWST) will enable spectroscopic observations of large samples of reionization-epoch galaxies. While the leakage of ionizing photons will not be directly measurable from these spectra, the leakage is predicted to have an indirect effect on the spectral slope and the strength of nebular emission lines in the rest-frame ultraviolet and optical. Here, we apply a machine learning technique known as lasso regression on mock JWST/NIRSpec observations of simulated z = 7 galaxies in order to obtain a model that can predict the escape fraction from JWST/NIRSpec data. Barring systematic biases in the simulated spectra, our method is able to retrieve the escape fraction with a mean absolute error of {{Δ }}{f}{esc}≈ 0.12 for spectra with signal-to-noise ratio ≈ 5 at a rest-frame wavelength of 1500 Å for our fiducial simulation. This prediction accuracy represents a significant improvement over previous similar approaches.

  6. High-speed scanning of critical structures in aviation using coordinate measurement machine and the laser ultrasonic.

    PubMed

    Swornowski, Pawel J

    2012-01-01

    Aviation is one of the know-how spheres containing a great deal of responsible sub-assemblies, in this case landing gear. The necessity for reducing production cycle times while achieving better quality compels metrologists to look for new and improved ways to perform inspection of critical structures. This article describes the ability to determine the shape deviation and location of defects in landing gear using coordinate measuring machines and laser ultrasonic with high-speed scanning. A nondestructive test is the basis for monitoring microcrack and corrosion propagation in the context of a damage-tolerant design approach. This article presents an overview of the basics and of the various metrological aspects of coordinate measurement and a nondestructive testing method in terms of high-speed scanning. The new test method (laser ultrasonic) promises to produce the necessary increase in inspection quality, but this is limited by the wide range of materials, geometries, and structure aeronautic parts used. A technique combining laser ultrasonic and F-SAFT (Fourier-Synthetic Aperture Focusing Technique) processing has been proposed for the detection of small defects buried in landing gear. The experimental results of landing gear inspection are also presented.

  7. A new test machine for measuring friction and wear in controlled atmospheres to 1200 C

    NASA Technical Reports Server (NTRS)

    Sliney, Harold E.; Dellacorte, Christopher

    1991-01-01

    This paper describes a new high-temperature friction and wear test apparatus (tribometer). The tribometer can be used as a pin-on-disk or pin-on-ring configuration and is specially designed to measure the tribological properties of ceramics and high temperature metallic alloys from room temperature to 1200 C. Sliding mode can be selected to be either unidirectional at velocities up to 22 m/sec or oscillating at frequencies up to 4.6 Hz and amplitudes up to + or - 60 deg. The test atmosphere is established by a controlled flow rate of a purge gas. All components within the test chamber are compatible with oxidizing, inert or reducing gases.

  8. A new test machine for measuring friction and wear in controlled atmospheres to 1200 C

    NASA Technical Reports Server (NTRS)

    Sliney, Harold E.; Dellacorte, Christopher

    1989-01-01

    This paper describes a new high temperature friction and wear test apparatus (tribometer) at NASA Lewis Research Center, Cleveland, Ohio. The tribometer can be used as a pin-on-disk or pin-on-ring configuration and is specially designed to measure the tribological properties of ceramics and high temperature metallic alloys from room temperature to 1200 C. Sliding mode can be selected to be either unidirectional at velocities up to 22 m/sec or oscillating at frequencies up 4.5 Hz and amplitudes up to + or - 60 deg. The test atmosphere is established by a controlled flow rate of a purge gas. All components within the test chamber are compatible with oxidizing, inert, or reducing gases.

  9. Measurements of the neutron dose equivalent for various radiation qualities, treatment machines and delivery techniques in radiation therapy

    NASA Astrophysics Data System (ADS)

    Hälg, R. A.; Besserer, J.; Boschung, M.; Mayer, S.; Lomax, A. J.; Schneider, U.

    2014-05-01

    In radiation therapy, high energy photon and proton beams cause the production of secondary neutrons. This leads to an unwanted dose contribution, which can be considerable for tissues outside of the target volume regarding the long term health of cancer patients. Due to the high biological effectiveness of neutrons in regards to cancer induction, small neutron doses can be important. This study quantified the neutron doses for different radiation therapy modalities. Most of the reports in the literature used neutron dose measurements free in air or on the surface of phantoms to estimate the amount of neutron dose to the patient. In this study, dose measurements were performed in terms of neutron dose equivalent inside an anthropomorphic phantom. The neutron dose equivalent was determined using track etch detectors as a function of the distance to the isocenter, as well as for radiation sensitive organs. The dose distributions were compared with respect to treatment techniques (3D-conformal, volumetric modulated arc therapy and intensity-modulated radiation therapy for photons; spot scanning and passive scattering for protons), therapy machines (Varian, Elekta and Siemens linear accelerators) and radiation quality (photons and protons). The neutron dose equivalent varied between 0.002 and 3 mSv per treatment gray over all measurements. Only small differences were found when comparing treatment techniques, but substantial differences were observed between the linear accelerator models. The neutron dose equivalent for proton therapy was higher than for photons in general and in particular for double-scattered protons. The overall neutron dose equivalent measured in this study was an order of magnitude lower than the stray dose of a treatment using 6 MV photons, suggesting that the contribution of the secondary neutron dose equivalent to the integral dose of a radiotherapy patient is small.

  10. Measurements of the neutron dose equivalent for various radiation qualities, treatment machines and delivery techniques in radiation therapy.

    PubMed

    Hälg, R A; Besserer, J; Boschung, M; Mayer, S; Lomax, A J; Schneider, U

    2014-05-21

    In radiation therapy, high energy photon and proton beams cause the production of secondary neutrons. This leads to an unwanted dose contribution, which can be considerable for tissues outside of the target volume regarding the long term health of cancer patients. Due to the high biological effectiveness of neutrons in regards to cancer induction, small neutron doses can be important. This study quantified the neutron doses for different radiation therapy modalities. Most of the reports in the literature used neutron dose measurements free in air or on the surface of phantoms to estimate the amount of neutron dose to the patient. In this study, dose measurements were performed in terms of neutron dose equivalent inside an anthropomorphic phantom. The neutron dose equivalent was determined using track etch detectors as a function of the distance to the isocenter, as well as for radiation sensitive organs. The dose distributions were compared with respect to treatment techniques (3D-conformal, volumetric modulated arc therapy and intensity-modulated radiation therapy for photons; spot scanning and passive scattering for protons), therapy machines (Varian, Elekta and Siemens linear accelerators) and radiation quality (photons and protons). The neutron dose equivalent varied between 0.002 and 3 mSv per treatment gray over all measurements. Only small differences were found when comparing treatment techniques, but substantial differences were observed between the linear accelerator models. The neutron dose equivalent for proton therapy was higher than for photons in general and in particular for double-scattered protons. The overall neutron dose equivalent measured in this study was an order of magnitude lower than the stray dose of a treatment using 6 MV photons, suggesting that the contribution of the secondary neutron dose equivalent to the integral dose of a radiotherapy patient is small.

  11. Retrieval of aerosol optical depth from surface solar radiation measurements using machine learning algorithms, non-linear regression and a radiative transfer-based look-up table

    NASA Astrophysics Data System (ADS)

    Huttunen, Jani; Kokkola, Harri; Mielonen, Tero; Esa Juhani Mononen, Mika; Lipponen, Antti; Reunanen, Juha; Vilhelm Lindfors, Anders; Mikkonen, Santtu; Erkki Juhani Lehtinen, Kari; Kouremeti, Natalia; Bais, Alkiviadis; Niska, Harri; Arola, Antti

    2016-07-01

    In order to have a good estimate of the current forcing by anthropogenic aerosols, knowledge on past aerosol levels is needed. Aerosol optical depth (AOD) is a good measure for aerosol loading. However, dedicated measurements of AOD are only available from the 1990s onward. One option to lengthen the AOD time series beyond the 1990s is to retrieve AOD from surface solar radiation (SSR) measurements taken with pyranometers. In this work, we have evaluated several inversion methods designed for this task. We compared a look-up table method based on radiative transfer modelling, a non-linear regression method and four machine learning methods (Gaussian process, neural network, random forest and support vector machine) with AOD observations carried out with a sun photometer at an Aerosol Robotic Network (AERONET) site in Thessaloniki, Greece. Our results show that most of the machine learning methods produce AOD estimates comparable to the look-up table and non-linear regression methods. All of the applied methods produced AOD values that corresponded well to the AERONET observations with the lowest correlation coefficient value being 0.87 for the random forest method. While many of the methods tended to slightly overestimate low AODs and underestimate high AODs, neural network and support vector machine showed overall better correspondence for the whole AOD range. The differences in producing both ends of the AOD range seem to be caused by differences in the aerosol composition. High AODs were in most cases those with high water vapour content which might affect the aerosol single scattering albedo (SSA) through uptake of water into aerosols. Our study indicates that machine learning methods benefit from the fact that they do not constrain the aerosol SSA in the retrieval, whereas the LUT method assumes a constant value for it. This would also mean that machine learning methods could have potential in reproducing AOD from SSR even though SSA would have changed during

  12. Verification of Entrance Dose Measurements with Thermoluminescent Dosimeters in Conventional Radiotherapy Procedures Delivered with Co-60 Teletherapy Machine

    PubMed Central

    Evwierhurhoma, OB; Ibitoye, ZA; Ojieh, CA; Duncan, JTK

    2015-01-01

    Background: The use of in vivo dosimetry with thermolumiscent dosimeters (TLDs) as a veritable means of quality control in conventional radiotherapy procedures was determined in this work. Aim: The objective of this study was to determine the role of in vivo dosimetry with thermoluminescent dosimeters (TLDs) as part of quality control and audit in conventional radiotherapy procedures delivered with Co-60 teletherapy machine. Subjects and Methods: Fifty-seven patients with cancers of the breast, pelvis, head and neck were admitted for this study. TLD system at the Radiation Monitoring and Protection Centre, Lagos State University, Ojo, Lagos-Nigeria was used for the in vivo entrance dose readings. All patients were treated with Co-60 (T780c) teletherapy machine at 80 cm source to surface distance located at Eko Hospitals, Lagos. Two TLDs were placed on the patient surface within 1 cm from the center of the field of treatment. Build-up material made of paraffin wax with a density of 0.939 g/cm3 and a thickness 0.5 cm was placed on top of the TLDs. A RADOS RE 200 TLD reader was used to read out the TLDs over 12 s and at a temperature of 300°C. Results: The results showed that there was no significant difference between the expected dose and measured dose of breast (P = 0.11), H and N (P = 0.52), and pelvis (P = 0.31) patients. Furthermore, percentage difference between expected dose and measured dose of the three treatment sites were not significantly different (P = 0.11). More so, 88.9% (16/18) treated breast, 91.3% (21/23) pelvis, and 86.7% (13/15) H and N patients had percentage deviation difference less than 5%. In general, 89.3% (50/56) patients admitted for this study had their percentage deviation difference below 5% recommended standard limit. Conclusion: The values obtained establish that there are no major differences from similar studies reported in literature. This study was also part of quality control and audit of the radiotherapy procedures in the

  13. Hindlimb heating increases vascular access of large molecules to murine tibial growth plates measured by in vivo multiphoton imaging.

    PubMed

    Serrat, Maria A; Efaw, Morgan L; Williams, Rebecca M

    2014-02-15

    Advances in understanding the molecular regulation of longitudinal growth have led to development of novel drug therapies for growth plate disorders. Despite progress, a major unmet challenge is delivering therapeutic agents to avascular-cartilage plates. Dense extracellular matrix and lack of penetrating blood vessels create a semipermeable "barrier," which hinders molecular transport at the vascular-cartilage interface. To overcome this obstacle, we used a hindlimb heating model to manipulate bone circulation in 5-wk-old female mice (n = 22). Temperatures represented a physiological range of normal human knee joints. We used in vivo multiphoton microscopy to quantify temperature-enhanced delivery of large molecules into tibial growth plates. We tested the hypothesis that increasing hindlimb temperature from 22°C to 34°C increases vascular access of large systemic molecules, modeled using 10, 40, and 70 kDa dextrans that approximate sizes of physiological regulators. Vascular access was quantified by vessel diameter, velocity, and dextran leakage from subperichondrial plexus vessels and accumulation in growth plate cartilage. Growth plate entry of 10 kDa dextrans increased >150% at 34°C. Entry of 40 and 70 kDa dextrans increased <50%, suggesting a size-dependent temperature enhancement. Total dextran levels in the plexus increased at 34°C, but relative leakage out of vessels was not temperature dependent. Blood velocity and vessel diameter increased 118% and 31%, respectively, at 34°C. These results demonstrate that heat enhances vascular carrying capacity and bioavailability of large molecules around growth plates, suggesting that temperature could be a noninvasive strategy for modulating delivery of therapeutics to impaired growth plates of children.

  14. A new optical flat surface measurement method based on machine vision and deflectometry

    NASA Astrophysics Data System (ADS)

    Kewei, E.; Li, Dahai; Yang, Lijie; Guo, Guangrao; Li, Mengyang; Wang, Xuemin; Zhang, Tao; Xiong, Zhao

    2016-10-01

    Phase Measuring Deflectometry(PMD) is a non-contact, high dynamic-range and full-field metrology which becomes a serious competitor to interferometry. However, the accuracy of deflectometry metrology is strongly influenced by the level of the calibrations. Our paper presents a calibration-based PMD method to test optical flat surface with a high accuracy. In our method, a pin-hole camera was set next to the LCD screen which is used to project sinusoidal fringes to the test flat. And the test flat was placed parallel to the direction of the LCD screen, which makes the geometry calibration process are simplified. The photogrammetric methods used in computer vision science was used to calibrate the pin-hole camera by using a checker pattern shown on another LCD display at six different orientations, the intrinsic parameters can be obtained by processing the obtained image of checker patterns. Further, by making the last orientation of checker pattern is aligned at the same position as the test optical flat, the algorithms used in this paper can obtain the mapping relationship between the CCD pixels and the subaperture coordinates on the test optical flat. We test a optical flat with a size of 50mm in diameter using our setup and algorithm. Our experimental results of optical flat figure from low to high order aberrations show a good agreement with that from the Fizeau interferometer.

  15. Sub-Plate Overlap Code Documentation

    NASA Technical Reports Server (NTRS)

    Taff, L. G.; Bucciarelli, B.; Zarate, N.

    1997-01-01

    An expansion of the plate overlap method of astrometric data reduction to a single plate has been proposed and successfully tested. Each plate is (artificially) divided into sub-plates which can then be overlapped. This reduces the area of a 'plate' over which a plate model needs to accurately represent the relationship between measured coordinates and standard coordinates. Application is made to non-astrographic plates such as Schmidt plates and to wide-field astrographic plates. Indeed, the method is completely general and can be applied to any type of recording media.

  16. Variation of seismic slip in the Gulf of California and the possible effect on geodetic measurements of Pacific-North American plate motion

    NASA Technical Reports Server (NTRS)

    Tajima, Fumiko; Tralli, David M.

    1992-01-01

    A simple dislocation model is used to evaluate the variation of seismic slip in the Gulf of California and the possible effect on geodetic measurements of Pacific-North American plate motion by means of an estimation of the surface displacements due to typical transform events in the gulf. The results of this numerical calculation suggest that if a large transform event (about 1.5 x 10 exp 26 dyne cm) were to occur within 100 to 200 km of a geodetic baseline, the relative distance measurements could be affected by up to 15 mm. This is marginally at the error level of a few millimeters plus 2 parts in 10 exp 8 of baseline length for GOMEX measurements, which thus are sensitive only to the far-field displacement along the plate boundary.

  17. Position and time resolution measurements with a microchannel plate image intensifier: A comparison of monolithic and pixelated CeBr3 scintillators

    NASA Astrophysics Data System (ADS)

    Ackermann, Ulrich; Eschbaumer, Stephan; Bergmaier, Andreas; Egger, Werner; Sperr, Peter; Greubel, Christoph; Löwe, Benjamin; Schotanus, Paul; Dollinger, Günther

    2016-07-01

    To perform Four Dimensional Age Momentum Correlation measurements in the near future, where one obtains the positron lifetime in coincidence with the three dimensional momentum of the electron annihilating with the positron, we have investigated the time and position resolution of two CeBr3 scintillators (monolithic and an array of pixels) using a Photek IPD340/Q/BI/RS microchannel plate image intensifier. The microchannel plate image intensifier has an active diameter of 40 mm and a stack of two microchannel plates in chevron configuration. The monolithic CeBr3 scintillator was cylindrically shaped with a diameter of 40 mm and a height of 5 mm. The pixelated scintillator array covered the whole active area of the microchannel plate image intensifier and the shape of each pixel was 2.5·2.5·8 mm3 with a pixel pitch of 3.3 mm. For the monolithic setup the measured mean single time resolution was 330 ps (FWHM) at a gamma energy of 511 keV. No significant dependence on the position was detected. The position resolution at the center of the monolithic scintillator was about 2.5 mm (FWHM) at a gamma energy of 662 keV. The single time resolution of the pixelated crystal setup reached 320 ps (FWHM) in the region of the center of the active area of the microchannel plate image intensifier. The position resolution was limited by the cross-section of the pixels. The gamma energy for the pixel setup measurements was 511 keV.

  18. Comprehensive property retrieval and measurement of concrete spalling using machine vision for post-earthquake safety assessments

    NASA Astrophysics Data System (ADS)

    German, Stephanie; Brilakis, Ioannis; DesRoches, Reginald

    2012-04-01

    Current procedures in post-earthquake safety and structural assessment are performed by a skilled triage team of structural engineers/certified inspectors. These procedures, in particular the physical measurement of the damage properties, are time-consuming and qualitative in nature. Spalling has been accepted as an important indicator of significant damage to structural elements during an earthquake, and thus provides a sound springboard for a model in machine vision automated assessment procedures as is proposed in this research. Thus, a novel method that automatically detects regions of spalling on reinforced concrete columns and measures their properties in image data is the specific focus of this work. According to this method, the region of spalling is first isolated by way of a local entropy-based thresholding algorithm. Following this, the properties of the spalled region are depicted by way of classification of the extent of spalling on the column. The region of spalling is sorted into one of three categories by way of a novel global entropy-based adaptive thresholding algorithm in conjunction with well-established image processing methods in template matching and morphological operations. These three categories are specified as the following: (1) No spalling; (2) Spalling of cover concrete; and (3) Spalling of the core concrete (exposing reinforcement). In addition, the extent of the spalling along the length of the column is quantified. The method was tested on a database of damaged RC column images collected after the 2010 Haiti Earthquake, and comparison of the results with manual measurements indicate the validity of the method.

  19. Layered Plating Specimens For Mechanical Tests

    NASA Technical Reports Server (NTRS)

    Thompson, Linda B.; Flowers, Cecil E.

    1991-01-01

    Layered specimens readily made in standard sizes for tensile and other tests of mechanical properties. Standard specimen of metal ordinarily difficult to plate to standard grip thickness or diameter made by augmentation with easier-to-plate material followed by machining to standard size and shape.

  20. Abdominal strengthening using the AbVice machine as measured by surface electromyographic activation levels.

    PubMed

    Avedisian, Lori; Kowalsky, Don S; Albro, Richard C; Goldner, Daniel; Gill, Robert C

    2005-08-01

    Twenty-four college students served as subjects in a study that examined the effect of a prototypical abdominal muscle strengthening device (AbVice) compared with other devices currently on the market. The purpose of the present study was to investigate a prototypical device (AbVice) that incorporates contraction of the hamstring and gluteal musculature in conjunction with the abdominals, which may assist in decreasing activation of the hip flexors by allowing greater activity levels of the abdominal musculature via the theory of reflex inhibition, compared with other devices currently available on the market (AbRoller and AbRocker). The repeated-measures study included 17 women and 7 men who ranged in age from 20-23 years (mean +/- SD age, 21.3 +/- 1.5 years). Each subject underwent a single session of data collection during which they completed 10 repetitions of abdominal crunches per device. Subjects completed 4 different crunch sets (AbRocker, AbRoller, standard crunch, AbVice). Counterbalancing of the device was used to negate the effect of fatigue. Speed of repetitions was ensured via use of a metronome set at 40 b.min(-1) to permit similar contraction times and rest periods between repetitions. Rest between conditions was 3 minutes. Mean activation levels of surface electromyography (EMG) were recorded for each condition at the following locations on the right side of the body: rectus abdominis 2.5 cm superior to the umbilicus, rectus abdominis 2.5 cm inferior to the umbilicus, external oblique abdominis 1.0 cm medial to the anterior superior iliac spine, and external oblique abdominis less than 1.0 cm superior to the inguinal ligament. Mean (SD) activation was 1,165.21 mV (634.60 mV) with the AbVice, 242.92 mV (263.03 mV) with the AbRocker, 753.29 mV (514.80 mV) with the standard crunch, and 757.67 mV (542.85 mV) with the AbRoller. Broken down by sex, women had the following mean (SD) EMG values: 1,079.76 mV (705.02 mV) with the AbVice, 680.35 mV (535.35 m

  1. Database machines

    NASA Technical Reports Server (NTRS)

    Stiefel, M. L.

    1983-01-01

    The functions and performance characteristics of data base machines (DBM), including machines currently being studied in research laboratories and those currently offered on a commerical basis are discussed. The cost/benefit considerations that must be recognized in selecting a DBM are discussed, as well as the future outlook for such machines.

  2. Advanced analytical methodologies for measuring healthy ageing and its determinants, using factor analysis and machine learning techniques: the ATHLOS project.

    PubMed

    Félix Caballero, Francisco; Soulis, George; Engchuan, Worrawat; Sánchez-Niubó, Albert; Arndt, Holger; Ayuso-Mateos, José Luis; Haro, Josep Maria; Chatterji, Somnath; Panagiotakos, Demosthenes B

    2017-03-10

    A most challenging task for scientists that are involved in the study of ageing is the development of a measure to quantify health status across populations and over time. In the present study, a Bayesian multilevel Item Response Theory approach is used to create a health score that can be compared across different waves in a longitudinal study, using anchor items and items that vary across waves. The same approach can be applied to compare health scores across different longitudinal studies, using items that vary across studies. Data from the English Longitudinal Study of Ageing (ELSA) are employed. Mixed-effects multilevel regression and Machine Learning methods were used to identify relationships between socio-demographics and the health score created. The metric of health was created for 17,886 subjects (54.6% of women) participating in at least one of the first six ELSA waves and correlated well with already known conditions that affect health. Future efforts will implement this approach in a harmonised data set comprising several longitudinal studies of ageing. This will enable valid comparisons between clinical and community dwelling populations and help to generate norms that could be useful in day-to-day clinical practice.

  3. Advanced analytical methodologies for measuring healthy ageing and its determinants, using factor analysis and machine learning techniques: the ATHLOS project

    PubMed Central

    Félix Caballero, Francisco; Soulis, George; Engchuan, Worrawat; Sánchez-Niubó, Albert; Arndt, Holger; Ayuso-Mateos, José Luis; Haro, Josep Maria; Chatterji, Somnath; Panagiotakos, Demosthenes B.

    2017-01-01

    A most challenging task for scientists that are involved in the study of ageing is the development of a measure to quantify health status across populations and over time. In the present study, a Bayesian multilevel Item Response Theory approach is used to create a health score that can be compared across different waves in a longitudinal study, using anchor items and items that vary across waves. The same approach can be applied to compare health scores across different longitudinal studies, using items that vary across studies. Data from the English Longitudinal Study of Ageing (ELSA) are employed. Mixed-effects multilevel regression and Machine Learning methods were used to identify relationships between socio-demographics and the health score created. The metric of health was created for 17,886 subjects (54.6% of women) participating in at least one of the first six ELSA waves and correlated well with already known conditions that affect health. Future efforts will implement this approach in a harmonised data set comprising several longitudinal studies of ageing. This will enable valid comparisons between clinical and community dwelling populations and help to generate norms that could be useful in day-to-day clinical practice. PMID:28281663

  4. Neutron Diffraction Measurement of Residual Stresses, Dislocation Density and Texture in Zr-bonded U-10Mo ''Mini'' Fuel Foils and Plates

    SciTech Connect

    Brown, Donald W.; Okuniewski, M. A.; Sisneros, Thomas A.; Clausen, Bjorn; Moore, G. A.; Balogh, L

    2014-08-07

    Aluminum clad monolithic uranium 10 weight percent molybdenum (U-10Mo) fuel plates are being considered for conversion of several research and test nuclear reactors from high-enriched to low-enriched uranium fuel due to the inherently high density of fissile material. Comprehensive neutron diffraction measurements of the evolution of the textures, residual phase stresses, and dislocation densities in the individual phases of the mini-foils throughout several processing steps and following hot-isostatic pressing to the Al cladding, have been completed. Recovery and recrystallization of the bare U-10Mo fuel foil, as indicated by the dislocation density and texture, are observed depending on the state of the material prior to annealing and the duration and temperature of the annealing process. In general, the HIP procedure significantly reduces the dislocation density, but the final state of the clad plate, both texture and dislocation density, depends strongly on the final processing step of the fuel foil. In contrast, the residual stresses in the clad fuel plate do not depend strongly on the final processing step of the bare foil prior to HIP bonding. Rather, the residual stresses are dominated by the thermal expansion mismatch of the constituent materials of the fuel plate.

  5. Machine Shop Fundamentals: Part I.

    ERIC Educational Resources Information Center

    Kelly, Michael G.; And Others

    These instructional materials were developed and designed for secondary and adult limited English proficient students enrolled in machine tool technology courses. Part 1 includes 24 lessons covering introduction, safety and shop rules, basic machine tools, basic machine operations, measurement, basic blueprint reading, layout, and bench tools.…

  6. TECHNICAL DESIGN NOTE: High-precision, low-coherence Fizeau interferometer using a pulsed laser diode for measurement of transparent plates

    NASA Astrophysics Data System (ADS)

    Bitou, Youichi; Ueki, Nobuaki

    2010-07-01

    A high-precision, low-coherence Fizeau interferometer system using a pulsed laser diode has been developed for the measurement of the flatness of transparent plates. A pulsed laser diode with a wavelength of around 633 nm was used as the low-coherence light source. A Twyman-Green interferometer with the pulsed laser diode was connected to the Fizeau interferometer. By adjusting the optical path differences in both interferometers, the interference fringe pattern due only to the reference and measurement surfaces could be observed. The accuracy of the measurements was found to be similar to that of a conventional Fizeau interferometer.

  7. Perforation of HY-100 steel plates with 4340 R{sub c} 38 and T-250 maraging steel rod projectiles

    SciTech Connect

    Forrestal, M.J.; Hanchak, S.J.

    1998-05-25

    The authors conducted perforation experiments with 4340 Rc 38 and T-250 maraging steel, long rod projectiles and HY-100 steel target plates at striking velocities between 80 and 370 m/s. Flat-end rod projectiles with lengths of 89 and 282 mm were machined to nominally 30-mm-diameter so they could be launched from a 30-mm-powder gun without sabots. The target plates were rigidly clamped at a 305-mm-diameter and had nominal thicknesses of 5.3 and 10.5 mm. Four sets of experiments were conducted to show the effects of rod length and plate thickness on the measured ballistic limit and residual velocities. In addition to measuring striking and residual projectile velocities, they obtained framing camera data on the back surfaces of several plates that showed clearly the plate deformation and plug ejection process. They also present a beam model that exhibits qualitatively the experimentally observed mechanisms.

  8. Effect of preheat on residual stress distributions in arc-welded mild steel plates

    SciTech Connect

    Adedayo, S.M.; Adeyemi, M.B.

    2000-02-01

    Residual stress distribution in the longitudinal and transverse directions on a 6-mm-thick arc-welded mild steel plate was experimentally examined with and without initial preheat. Stress measurements were completed by monitoring strain changes on mounted strain gauges resulting from successive milling of the welded plate specimens. Machining stresses were also compensated for by carrying out measurements of strain changes due to milling operation of a stress-free unwelded annealed mild steel plate. High tensile residual stresses exist close to the weld line in both longitudinal and transverse stresses. Maximum longitudinal residual stress values existing close to the weld line are reduced (between 50 and 75%) due to the effect of initial metal preheat of 200 C of the welded steel plate.

  9. S/Ka Dichroic Plate with Rounded Corners for NASA's 34-m Beam-Waveguide Antenna

    NASA Astrophysics Data System (ADS)

    Veruttipong, W.; Khayatian, B.; Imbriale, W.

    2016-02-01

    An S-/Ka-band frequency selective surface (FSS) or a dichroic plate is designed, manufactured, and tested for use in NASA's Deep Space Network (DSN) 34-m beam-waveguide (BWG) antennas. Due to its large size, the proposed dichroic incorporates a new design feature: waveguides with rounded corners to cut cost and allow ease of manufacturing the plate. The dichroic is designed using an analysis that combines the finite-element method (FEM) for arbitrarily shaped guides with the method of moments and Floquet mode theory for periodic structures. The software was verified by comparison with previously measured and computed dichroic plates. The large plate was manufactured with end-mill machining. The RF performance was measured and is in excellent agreement with the analytical results. The dichroic has been successfully installed and is operational at DSS-24, DSS-34, and DSS-54.

  10. [The study of selecting sample detecting position and lead plate inner material in thin film method X-ray fluorescence measurement].

    PubMed

    Gan, Ting-ting; Zhang, Yu-jun; Zhao, Nan-jing; Yin, Gao-fang; Dong, Xin-xin; Wang, Ya-ping; Liu Jian-guo; Liu, Wen-qing

    2015-01-01

    (1) In this paper type 316 stainless steel metal plate as the research object, the selection of sample detecting position was studied when thin film method X-ray fluorescence measurement was conducted. The study showed that the optimal location for the sample detection was sample distance X-ray tube and detector baseline 1cm with the baseline into a 16°angle. (2) Heavy metal pollutants of Pb, Cd and Cr in industrial ambient air as the main analysis object, when thin film method X-ray fluorescence conducted with lead plate protection, X-rays will penetrate the membrane and continuely stimulate the protective lead plate. Therefore there is lead spectral line interference in the filter membrane background spectrum, which will affect the detection of lead element in real samples. Studies show that when a layer of isolating material was applied between the thin sample and the protective lead plate, the interference of lead line can effectively be avoided. (3) Several rigid insulating material of type 316 stainless steel, brass, aluminum, red copper and PTEE as lead inner material were selected and studied. The study results showed that compared with X-ray fluorescence spectra of other lead inner materials, the X-ray fluorescence spectrum of red copper contained the least element spectral lines. There were not Cr, Cd and Pb spectrum peaks in the X-ray fluorescence spectrum of red copper. And the target timber scattering spectrum intensity in the high energy part was weaker compared to other X-ray fluorescence spectrum. The above analysis shows that red copper has the minimal disturbance to the actual measurement of heavy metals Cr, Cd and Pb. At the same time, red copper as lead inner materials can effectively avoid the interference of lead spectrum line in lead plate. So red copper is the best lead plate inner materials in thin film method X-ray fluorescence spectroscopy measurement. This study provides an important theoretical basis for the assembling and setting

  11. Mass flow rate measurements in gas-liquid flows by means of a venturi or orifice plate coupled to a void fraction sensor

    SciTech Connect

    Oliveira, Jorge Luiz Goes; Passos, Julio Cesar

    2009-01-15

    Two-phase flow measurements were carried out using a resistive void fraction meter coupled to a venturi or orifice plate. The measurement system used to estimate the liquid and gas mass flow rates was evaluated using an air-water experimental facility. Experiments included upward vertical and horizontal flow, annular, bubbly, churn and slug patterns, void fraction ranging from 2% to 85%, water flow rate up to 4000 kg/h, air flow rate up to 50 kg/h, and quality up to almost 10%. The fractional root mean square (RMS) deviation of the two-phase mass flow rate in upward vertical flow through a venturi plate is 6.8% using the correlation of Chisholm (D. Chisholm, Pressure gradients during the flow of incompressible two-phase mixtures through pipes, venturis and orifice plates, British Chemical Engineering 12 (9) (1967) 454-457). For the orifice plate, the RMS deviation of the vertical flow is 5.5% using the correlation of Zhang et al. (H.J. Zhang, W.T. Yue, Z.Y. Huang, Investigation of oil-air two-phase mass flow rate measurement using venturi and void fraction sensor, Journal of Zhejiang University Science 6A (6) (2005) 601-606). The results show that the flow direction has no significant influence on the meters in relation to the pressure drop in the experimental operation range. Quality and slip ratio analyses were also performed. The results show a mean slip ratio lower than 1.1, when bubbly and slug flow patterns are encountered for mean void fractions lower than 70%. (author)

  12. Plate Thickness Variation Effects on Crack Growth Rates in 7050-T7451 Alloy Thick Plate

    NASA Astrophysics Data System (ADS)

    Schubbe, Joel J.

    2011-02-01

    A study has been accomplished to characterize the fatigue crack growth rates and mechanisms in thick plate (16.51 cm) commercial grade 7050-T7451 aluminum plate in the L-S orientation. Examination of the effects of potential property gradients in the plate material was accomplished through hardness measurements along the short transverse direction and with compact tension tests. Tests exhibited a distinct trend of reduced center plane hardness in the plates. Compact tension specimens and the compliance method were used to determine crack growth rates for specimens machined from the t/4 and t/2 planar locations and oriented for L-S crack growth. Crack growth rate data (long crack) from the tests highlighted significant growth rate differences between the t/4 and t/2 locations. No significant effect of R-ratio was observed in the 0.05-0.3 range tested. Additionally, crack front splitting was noted in all specimens to differing degrees with data showing significant retardation of growth rate curves for the L-S orientation above 13 MPa √m in the center plane, and 10 MPa √m at quarter plane, where branching and splitting parallel to the load axis are dominant growth mechanisms.

  13. Estimates of Continental Plate Motions Derived From Continuous GPS Measurements of Station Coordinates and Velocities, 1996-2004

    NASA Astrophysics Data System (ADS)

    Hutchison, D. A.

    2004-05-01

    Analysis Centres of the International GPS Service (IGS) currently compute daily Earth Rotation Parameters (ERPs) and weekly precise coordinates for over 200 globally distributed tracking stations. These estimates are made available to the scientific community in the Solution Independent Exchange (SINEX) format, developed for exchange and analysis of position estimates from techniques such as SLR, LLR, VLBI, DORIS and GPS. On behalf of the IGS, National Resources Canada (NRCan) has been combining, officially since 1999, all weekly SINEX files from the ACs to form weekly and cumulative solutions. The weekly solution (named igsyyPwwww, yy = 2-digit year, wwww = 4-digit GPS week) contains estimates of station coordinates, ERPs and geocentre pertaining to the GPS week, and the cumulative solution (named IGSyyPWW, WW = 2-digit week number, 01 to 52, within the year) comprises station coordinates and velocities in a common reference epoch, Jan. 1, 1998. For example, two solutions produced for week 1253 (2nd week of year 2004) were igs04P1253 (weekly) and IGS04P02 (cumulative). Since week 1253, all IGS solutions have been aligned to IGb00, a realization of IGS's most recent International Terrestrial Reference Frame, ITRF2000. IGb00 was obtained from coordinates and velocities of 99 globally distributed reference stations by alignment to ITRF2000 at GPS week 1231 of cumulative solution IGS03P33. Before week 1143, a realization of IGS's previous reference frame, ITRF97, was used instead. Using the cumulative solution from any given week, the rotation components of any continental plate with at least two stations are estimated and compared with published results. These include three known plate models: NNR NUVEL 1, NNR NUVEL 1A and the most recent REVEL 2000 aligned to ITRF97. The findings can be summarized as follows: Continental rotations derived from IGS04P02 are shown to be significantly different at 99% confidence level from NNR NUVEL 1A's estimates for North American

  14. Dimensional metrology of bipolar fuel cell plates using laser spot triangulation probes

    NASA Astrophysics Data System (ADS)

    Muralikrishnan, Bala; Ren, Wei; Everett, Dennis; Stanfield, Eric; Doiron, Ted

    2011-07-01

    As in any engineering component, manufacturing a bipolar fuel cell plate for a polymer electrolyte membrane (PEM) hydrogen fuel cell power stack to within its stated design tolerances is critical in achieving the intended function. In a bipolar fuel cell plate, the dimensional features of interest include channel width, channel height, channel parallelism, side wall taper, straightness of the bottom or side walls, plate parallelism, etc. Such measurements can be performed on coordinate measuring machines (CMMs) with micro-probes that can access the narrow channels. While CMM measurements provide high accuracy (less than 1 µm), they are often very slow (taking several hours to measure a single plate) and unsuitable for the manufacturing environment. In this context, we describe a system for rapid dimensional measurement of bipolar fuel cell plates using two laser spot triangulation probes that can achieve comparable accuracies to those of a touch probe CMM, while offering manufacturers the possibility for 100% part inspection. We discuss the design of the system, present our approach to calibrating system parameters, present validation data, compare bipolar fuel cell plate measurement results with those obtained using a Mitutoyo UMAP (see footnote 1) fiber probe CMM, and finally describe the uncertainty in channel height and width measurements.

  15. Peen plating

    NASA Technical Reports Server (NTRS)

    Babecki, A. J. (Inventor); Haehner, C. L.

    1973-01-01

    A process for metal plating which comprises spraying a mixture of metallic powder and small peening particles at high velocity against a surface is described. The velocity must be sufficient to impact and bond metallic powder onto the surface. In the case of metal surfaces, the process has as one of its advantages providing mechanical working (hardening) of the surface simultaneously with the metal plating.

  16. Time-lapse 3-D measurements of a glucose biosensor in multicellular spheroids by light sheet fluorescence microscopy in commercial 96-well plates

    PubMed Central

    Maioli, Vincent; Chennell, George; Sparks, Hugh; Lana, Tobia; Kumar, Sunil; Carling, David; Sardini, Alessandro; Dunsby, Chris

    2016-01-01

    Light sheet fluorescence microscopy has previously been demonstrated on a commercially available inverted fluorescence microscope frame using the method of oblique plane microscopy (OPM). In this paper, OPM is adapted to allow time-lapse 3-D imaging of 3-D biological cultures in commercially available glass-bottomed 96-well plates using a stage-scanning OPM approach (ssOPM). Time-lapse 3-D imaging of multicellular spheroids expressing a glucose Förster resonance energy transfer (FRET) biosensor is demonstrated in 16 fields of view with image acquisition at 10 minute intervals. As a proof-of-principle, the ssOPM system is also used to acquire a dose response curve with the concentration of glucose in the culture medium being varied across 42 wells of a 96-well plate with the whole acquisition taking 9 min. The 3-D image data enable the FRET ratio to be measured as a function of distance from the surface of the spheroid. Overall, the results demonstrate the capability of the OPM system to measure spatio-temporal changes in FRET ratio in 3-D in multicellular spheroids over time in a multi-well plate format. PMID:27886235

  17. Time-lapse 3-D measurements of a glucose biosensor in multicellular spheroids by light sheet fluorescence microscopy in commercial 96-well plates

    NASA Astrophysics Data System (ADS)

    Maioli, Vincent; Chennell, George; Sparks, Hugh; Lana, Tobia; Kumar, Sunil; Carling, David; Sardini, Alessandro; Dunsby, Chris

    2016-11-01

    Light sheet fluorescence microscopy has previously been demonstrated on a commercially available inverted fluorescence microscope frame using the method of oblique plane microscopy (OPM). In this paper, OPM is adapted to allow time-lapse 3-D imaging of 3-D biological cultures in commercially available glass-bottomed 96-well plates using a stage-scanning OPM approach (ssOPM). Time-lapse 3-D imaging of multicellular spheroids expressing a glucose Förster resonance energy transfer (FRET) biosensor is demonstrated in 16 fields of view with image acquisition at 10 minute intervals. As a proof-of-principle, the ssOPM system is also used to acquire a dose response curve with the concentration of glucose in the culture medium being varied across 42 wells of a 96-well plate with the whole acquisition taking 9 min. The 3-D image data enable the FRET ratio to be measured as a function of distance from the surface of the spheroid. Overall, the results demonstrate the capability of the OPM system to measure spatio-temporal changes in FRET ratio in 3-D in multicellular spheroids over time in a multi-well plate format.

  18. Determination of thickness and elastic constants of aluminum plates from full-field wavelength measurements of single-mode narrowband Lamb waves.

    PubMed

    Deán, J Luis; Trillo, Cristina; Doval, Angel F; Fernández, José L

    2008-09-01

    A method based on fitting the theoretical dispersion curves of Lamb waves to experimental data is presented to determine the thickness and two independent elastic constants of aluminum plates a few millimeters thick. The waves are generated by means of the wedge method using a narrowband source, selecting the wedge angle and the acoustic frequency f so that mainly one mode is excited. A self-developed pulsed electronic speckle pattern interferometry system renders a two dimensional map of the out-of-plane acoustic displacement field at the plate surface, which allows an accurate measurement of the acoustic wavelength lambda(1). For any mode, the relation between lambda(1) and f depends on the three unknown parameters, so at least three experimental measurements (lambda(1i),f(i)) with different frequencies and/or different modes are required to calculate them. The suitability of different Lamb modes to determine each parameter when the others are known is studied, as well as the conditions that the experimental set of values must fulfill to calculate all three parameters. Numerous Lamb modes at different frequencies are generated in each plate, and a fitting is made based on the minimization of the error function, resulting in an accuracy better than 1%.

  19. Time-lapse 3-D measurements of a glucose biosensor in multicellular spheroids by light sheet fluorescence microscopy in commercial 96-well plates.

    PubMed

    Maioli, Vincent; Chennell, George; Sparks, Hugh; Lana, Tobia; Kumar, Sunil; Carling, David; Sardini, Alessandro; Dunsby, Chris

    2016-11-25

    Light sheet fluorescence microscopy has previously been demonstrated on a commercially available inverted fluorescence microscope frame using the method of oblique plane microscopy (OPM). In this paper, OPM is adapted to allow time-lapse 3-D imaging of 3-D biological cultures in commercially available glass-bottomed 96-well plates using a stage-scanning OPM approach (ssOPM). Time-lapse 3-D imaging of multicellular spheroids expressing a glucose Förster resonance energy transfer (FRET) biosensor is demonstrated in 16 fields of view with image acquisition at 10 minute intervals. As a proof-of-principle, the ssOPM system is also used to acquire a dose response curve with the concentration of glucose in the culture medium being varied across 42 wells of a 96-well plate with the whole acquisition taking 9 min. The 3-D image data enable the FRET ratio to be measured as a function of distance from the surface of the spheroid. Overall, the results demonstrate the capability of the OPM system to measure spatio-temporal changes in FRET ratio in 3-D in multicellular spheroids over time in a multi-well plate format.

  20. Pressure Measurements in a PBX 9501 Gauged Acceptor When Impacted by a Steel Plate that is Accelerated by a Thermally Cooked Off PBX 9501 Charge

    SciTech Connect

    Forbes, J W; Garcia, F; Urtiew, P A; Vandersall, K S; Greenwood, D W; Tarver, C M

    2002-03-11

    Measuring the violence of a thermal explosion of a cased explosive is important for evaluating safety issues of explosive devices in fires. A sympathetic initiation scenario was studied here where a 9.0 cm diameter by 2.5 cm thick disc of PBX 9501 donor charge encased in a 304 stainless steel assembly was heated on top and bottom flat surfaces until it thermally exploded. The initial heating rate at the metal/explosive interface was 5 C per minute until it reaches 170 C; then this temperature is held for 35 minutes to allow temperature equilibration to within a few degrees throughout the explosive. The heating resumed at a rate of 1 C per minute until the PBX 9501 donor thermally exploded. A PBX 9501 acceptor charge with carbon resistor and manganin foil pressure gauges inserted at various depths was placed at a 10 cm standoff distance from the donor charge's top steel cover plate. Piezoelectric arrival time pins were placed in front of the acceptor surface to measure the velocity and shape of the impacting plate. The stainless steel cover plate of the donor charge had a nominal velocity of 0.55 {+-} 0.04 mm/{micro}s upon impact and was non-symmetrically warped. The impact of the tilted curved plate induced a three-dimensional compression wave into the acceptor. The rise times of the pressure waves were nominally 1.5 {micro}s with the closest carbon resistor gauges giving peak pressure of 10 kb that decayed to 3 kb for a wave run distance of 2.4 cm.

  1. Electric machine

    DOEpatents

    El-Refaie, Ayman Mohamed Fawzi [Niskayuna, NY; Reddy, Patel Bhageerath [Madison, WI

    2012-07-17

    An interior permanent magnet electric machine is disclosed. The interior permanent magnet electric machine comprises a rotor comprising a plurality of radially placed magnets each having a proximal end and a distal end, wherein each magnet comprises a plurality of magnetic segments and at least one magnetic segment towards the distal end comprises a high resistivity magnetic material.

  2. Charge coupled devices vs. microchannel plates in the extreme and far ultraviolet - A comparison based on the latest laboratory measurements

    NASA Technical Reports Server (NTRS)

    Vallerga, J.; Lampton, M.

    1988-01-01

    While microchannel plates (MCPs) have been established as imaging photon counters in the EUV and FUV for some years, CCDs are associated with low light level sensing at visible and near-IR wavelengths. Attention is presently given to recent proposals for CCDs' use as EUV and FUV detectors with quantum efficiencies sometimes exceeding those of MCPs; quantum resolution, format size, dynamic range, and long-term stability are also used as bases of comparison, for the cases of both space-based astronomical and spectroscopic applications.

  3. Measurement of spatial distribution of neutrons and gamma rays for BNCT using multi-imaging plate system.

    PubMed

    Tanaka, Kenichi; Sakurai, Yoshinori; Tanaka, Hiroki; Kajimoto, Tsuyoshi; Takata, Takushi; Takada, Jun; Endo, Satoru

    2015-12-01

    Quality assurance of the spatial distributions of neutrons and gamma rays was tried using imaging plates (IPs) and converters to enhance the beam components in the epithermal neutron mode of the Kyoto University Reactor. The converters used were 4mm thick epoxy resin with B4C at 6.85 weight-percent (wt%) (10)B for epithermal neutrons, and 3mm thick carbon for gamma rays. Results suggested that the IP signal does not need a sensitivity correction regardless of the incident radiation that produces it.

  4. Uniqueness in the determination of vibration sources in rectangular Germain-Lagrange plates using displacement measurements over line segments with arbitrary small length

    NASA Astrophysics Data System (ADS)

    Kawano, Alexandre

    2013-08-01

    The theme of this work is related to the field of vibration and source detection, which is important in naval, aerospace and civil engineering industries. The detection of unexpected vibration sources, in general, signals malfunctioning, or even an undesired presence in the case of defense systems. The focus will be on thin plates, which are among the basic building blocks of large complex structures. Here, we consider loads acting on a rectangular plate R of the product form g(t)Q(x), where the function of time g has a continuous first derivative and the spatial load distribution Q is a square-integrable function over R. We prove that the observation of the displacement of a line segment with arbitrary length parallel to one of the sides of the plate is enough for the determination of Q, provided that the interval of time is long enough. We also prove that the normal derivative along a side of the rectangle measured for an arbitrarily small interval of time is sufficient to determine the spatial load distribution Q. The method used to obtain the results is based on the series decomposition of the dynamic response and an analysis of the almost periodic distribution that arises from it.

  5. Neutron diffraction measurement of residual stresses, dislocation density and texture in Zr-bonded U-10Mo “mini” fuel foils and plates

    DOE PAGES

    Brown, Donald William; Okuniewski, Maria A.; Sisneros, Thomas A.; ...

    2016-12-01

    Here, Al clad U-10Mo fuel plates are being considered for conversion of several research reactors from high-enriched to low-enriched U fuel. Neutron diffraction measurements of the textures, residual phase stresses, and dislocation densities in the individual phases of the mini-foils throughout several processing steps and following hot-isostatic pressing to the Al cladding, have been completed. Recovery and recrystallization of the bare U-10Mo fuel foil, as indicated by the dislocation density and texture, are observed depending on the state of the material prior to annealing and the duration and temperature of the annealing process. In general, the cladding procedure significantly reducesmore » the dislocation density, but the final state of the clad plate, both texture and dislocation density, depends strongly on the final processing step of the fuel foil. In contrast, the residual stress state of the final plate is dominated by the thermal expansion mismatch of the constituent materials.« less

  6. Application of the Pseudo Wigner-Ville Distribution to the Measurement of the Dispersion of Lamb Modes in Graphite/Epoxy Plates

    NASA Technical Reports Server (NTRS)

    Prosser, W. H.; Seale, M. D.; Smith, B. T.

    1997-01-01

    Acoustic waves propagate in thin plates as guided or Lamb modes. The velocities of these modes are dispersive in that they depend not only on the material elastic properties and density, but also on the frequency. Accurate characterization of Lamb wave dispersion is important in many acoustic based nondestructive evaluation techniques. It is necessary for ultrasonic measurements in thin plates to determine elastic properties and for flaw detection and localization. In acoustic emission (AE) testing, if not taken into account, highly dispersive Lamb mode propagation can lead to large errors in source location. In this study, the pseudo Wigner-Ville distribution (PWVD) was used for measurement of group velocity dispersion of Lamb waves in a unidirectional graphite/epoxy (AS4/3502) laminate. The PWVD is one of a number of transforms which provide a time-frequency representation of a digitized time series. Broad band acoustic waves were generated by a pencil lead fracture (Hsu-Neilsen source) and were detected with broad band ultrasonic transducers. The arrival times for the lowest order symmetric (S(sub 0)) and antisymmetric (A(sub 0)) Lamb modes were determined from measurements of the time at which the respective peak amplitudes occurred in the PWVD. Measurements were made at several source-to-detector distances and a least squares fit used to calculate the velocity. Results are presented for propagation along, and perpendicular to, the fiber direction. Theoretical dispersion curves were also calculated and a comparison between theory and experiment demonstrates good agreement.

  7. A 14-year-long Measurement of the Convergence Rate of the Juan de Fuca and North America Plates Offshore Central Oregon using GPS-Acoustics

    NASA Astrophysics Data System (ADS)

    Chadwell, C. D.; Webb, S. C.; Nooner, S. L.

    2015-12-01

    The motion of the sea floor was measured at a 3000-m-deep site approximately 120 km offshore Central Oregon using the GPS-Acoustic technique in 2000, 2001, 2002, 2003 and 2014. The GPS-Acoustic derived motion relative to the interior of North America agrees with the geomagnetically-derived value within their measurement uncertainties. The time series from the early 2000's was resurrected using two new innovations. The first innovation, a permanent benchmark that has locating channels and mating pins, allows reoccupation of an established benchmark at any later date using an ROV to replace the transponder on the benchmark. The second innovation: an autonomous platform based on a Waveglider that carries a GPS navigated acoustic transponder interrogation system that is wave and solar powered. This enables measurements to be obtained over a GPSA site without requiring a large ship, greatly reducing the cost of a GPSA measurement. Combining data at this site with data from two other GPS-Acoustic seafloor sites on the Juan de Fuca plate, makes it possible to determine a present-day Euler Pole for the Juan de Fuca - North America plates using GPS-Acoustics seafloor geodesy.

  8. Corrosion rates of stainless steel under shear stress measured by a novel parallel-plate flow chamber.

    PubMed

    Messer, Regina L W; Mickalonis, John; Adams, Yolanda; Tseng, Wan Y

    2006-02-01

    A unique parallel-plate flow chamber has been engineered to assess the corrosion properties of implant materials in biological environments under shear flow. This parallel-plate flow chamber provides a novel approach to investigate hypotheses regarding cellular-material-mechanical-force interactions that influence the success or failure of implant devices. The results of the current study demonstrated that physiological stresses (0.5-50 dynes/cm2) from laminar flow from cell culture media did not significantly alter corrosion rates of stainless steel, providing baseline information for an extensive study of the cellular-material-mechanical-force interactions. Furthermore, this study demonstrated that this device is electrochemically stable and provides reproducible results within test parameters. In addition, the results were not significantly different from corrosion tests on bulk samples. Therefore, this system will be useful for investigating cell-material interactions under shear stress for implant alloys or other opaque materials. This information is currently lacking. The results of the present study also support further development of this test system to assess cellular responses to these materials under shear stresses.

  9. The tabletting machine as an analytical instrument: qualification of the measurement devices for punch forces and validation of the calibration procedures.

    PubMed

    Belda, P M; Mielck, J B

    1998-11-01

    The quality of force measurement in an eccentric tabletting machine equipped with piezo-electric load washers mounted under pre-stress at the upper and lower punches, and the reliability of their calibration in situ and under working conditions were carefully investigated, since this tabletting machine is used as an 'analytical instrument' for the evaluation of the compression behaviour of pharmaceutical materials. For a quasistatic calibration procedure the repeatability under standard conditions and the robustness against variations in machine settings, installation conditions, equipment and handling were evaluated. Two differently constructed reference load cells equipped with strain gauges were used for the calibration of the upper punch sensor. The lower punch sensor was calibrated against the upper one. Except for a mechanical hysteresis, owing to uneven stress distribution over the piezo-electric sensors, the results of the quasistatic measurements are assessed to be satisfactory. In addition, dynamic calibrations were performed. One of the strain-gauged load cells was used in addition to two piezo-electric load washers installed without pre-stress. The dynamic behaviour of all the transducers used is deficient. While for the piezo-electric sensors a significant change in the slope of the calibration function with respect to the quasistatic behaviour was observed, for the strain-gauged load cell a pronounced hysteresis must be noted. Comparing the dynamic behaviour at different profiles of rates of force development generated by variations in machine speed and by maximum force setting, the variability in the sensitivity of the upper and lower punch piezo-electric load washers is comparatively small.

  10. True Shear Parallel Plate Viscometer

    NASA Technical Reports Server (NTRS)

    Ethridge, Edwin; Kaukler, William

    2010-01-01

    This viscometer (which can also be used as a rheometer) is designed for use with liquids over a large temperature range. The device consists of horizontally disposed, similarly sized, parallel plates with a precisely known gap. The lower plate is driven laterally with a motor to apply shear to the liquid in the gap. The upper plate is freely suspended from a double-arm pendulum with a sufficiently long radius to reduce height variations during the swing to negligible levels. A sensitive load cell measures the shear force applied by the liquid to the upper plate. Viscosity is measured by taking the ratio of shear stress to shear rate.

  11. Development and Demonstration of a Device to Determine Thrust by Measuring the Force on a Target Plate in the Exhaust of a Plasma Thruster

    NASA Technical Reports Server (NTRS)

    Chavers, Greg; Chang-Diaz, Franklin

    2004-01-01

    A device has been developed to measure the force on a target plate by an impacting beam of charged and neutral particles. This device, an impact thrust stand, was developed to allow thrusters at low TRL, levels to be easily tested without the expense of developing a flight prototype of the thruster to be placed on a conventional thrust stand. The impact thrust stand was developed for the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) but has been tested and calibrated using several devices including Hall thrusters. The calibration and comparison of the impact thrust stand against conventional thrust stands will be discussed in this paper.

  12. Development of a Highly Portable Plate Loading Device and In Situ Modulus Measurements in Weak Rock Masses

    NASA Astrophysics Data System (ADS)

    Kallu, Raj R.; Keffeler, Evan R.; Watters, Robert J.; Warren, Sean N.

    2016-02-01

    In recent years, underground mines in Nevada are increasingly exploiting in weak mineralized zones at greater depths that are intensely fractured and highly altered. The mechanical behavior of these rock masses ranges between weak rock and very stiff soil. A common limitation for design of underground mining excavations in these types of rock masses is absence of in situ geotechnical data. This limitation is generally overcome by estimating in situ mechanical behavior from empirical relationships so that the continuum-based numerical methods can be used to evaluate ground support designs. Because of the cost, time, and specialized equipment involved, historically in situ tests have not been performed in these underground mines. Predictive rock mass modulus relationships that are currently available in the literature are derived from field testing of predominantly good-quality rock masses. Consequently, there is limited confidence in using these models for rock masses with Rock Mass Ratings less than 45. In order to overcome some of these limitations, a portable plate loading device (PPLD) was designed and fabricated. The PPLD allows one to perform low cost and relatively quick in situ deformability tests to be performed on weak rock masses in underground mines. Test procedures and data reduction methods were developed to limit potential sources of error associated with the PPLD test. A total of fourteen plate loading tests were performed in weak rock masses at two different active underground mines in Nevada, USA. The resulting the test data were compared to eight published empirical rock mass modulus relationships to determine which, if any, of these relationships are sufficiently accurate for estimating modulus in similar geotechnical conditions. Only two of these relationships were found to be sufficient for first-order estimations of in situ modulus.

  13. [Application of infrared spectroscopy technique to protein content fast measurement in milk powder based on support vector machines].

    PubMed

    Wu, Di; Cao, Fang; Feng, Shui-Juan; He, Yong

    2008-05-01

    In the present study, the JASCO Model FTIR-4 000 fourier transform infrared spectrometer (Japan) was used, with a valid range of 7 800-350 cm(-1). Seven brands of milk powder were bought in a local supermarket. Milk powder was compressed into a uniform tablet with a diameter of 5 mm and a thickness of 2 mm, and then scanned by the spectrometer. Each sample was scanned 40 times and the data were averaged. About 60 samples were measured for each brand, and data for 409 samples were obtained. NIRS analysis was based on the range of 4 000 to 6 666 cm(-1), while MIRS analysis was between 400 and 4 000 cm(-1). The protein content was determined by kjeldahl method and the factor 6.38 was used to convert the nitrogen values to protein. The protein content value is the weight of protein per 100 g of milk powder. The NIR data of the milk powder exhibited slight differences. Univariate analysis was not really appropriate for analyzing the data sets. From NIRS region, it could be observed that the trend of different curves is similar. The one around 4 312 cm(-1) embodies the vibration of protein. From MIRS region, it could be determined that there are many differences between transmission value curves. Two troughs around 1 545 and 1 656 cm(-1) stand for the vibration of amide I and II bands of protein. The smoothing way of Savitzky-Golay with 3 segments and zero polynomials and multiplicative scatter correction (MSC) were applied for denoising. First 8 important principle components (PCs), which were obtained from principle component analysis (PCA), were the optimal input feature subset. Least-squares support vector machines was applied to build the protein prediction model based on infrared spectral transmission value. The prediction result was better than that of traditional PLS regression model as the determination coefficient for prediction (R(p)2) is 0.951 7 and root mean square error for prediction (RMSEP) is 0.520 201. These indicate that LS-SVM is a powerful tool for

  14. Rapidly Moving Divertor Plates In A Tokamak

    SciTech Connect

    S. Zweben

    2011-05-16

    It may be possible to replace conventional actively cooled tokamak divertor plates with a set of rapidly moving, passively cooled divertor plates on rails. These plates would absorb the plasma heat flux with their thermal inertia for ~10-30 sec, and would then be removed from the vessel for processing. When outside the tokamak, these plates could be cooled, cleaned, recoated, inspected, and then returned to the vessel in an automated loop. This scheme could provide nearoptimal divertor surfaces at all times, and avoid the need to stop machine operation for repair of damaged or eroded plates. We describe various possible divertor plate designs and access geometries, and discuss an initial design for a movable and removable divertor module for NSTX-U.

  15. Analysis of the coupling between shear horizontal plate waves and liquids: Application to the measurement of the shear rigidity modulus of glycerol solutions

    NASA Astrophysics Data System (ADS)

    Teston, F.; Feuillard, G.; Tessier, L.; Tran Hu Hue, L. P.; Lethiecq, M.

    2000-01-01

    This article presents an acoustic wave viscometer based on the shear horizontal acoustic plate mode excited by interdigital transducers on a ST-cut quartz substrate. A theoretical model, which is an extension of the plate effective permittivity function taking into account the presence of liquids, is developed in order to predict the phase and attenuation variations versus the viscosity of liquid. These results are discussed and compared to those of models from the literature such as variational or perturbation methods. The measured results for aqueous solutions of glycerol show linear dependence between the phase and attenuation variations and the square root of liquid viscosity, and are consistent with the theoretical results. The device can be used for viscosity measurements up to 1000 mPa s. For higher viscosities, the viscoelastic behavior of the solution appears and the shear rigidity modulus must be taken into account. The value of μ∞=2.5×109N m2 has been obtained for glycerol by fitting the theoretical curves to the experimental points.

  16. An undergraduate laboratory experiment for measuring ε 0, μ 0 and speed of light c with do-it-yourself catastrophe machines: electrostatic and magnetostatic pendula

    NASA Astrophysics Data System (ADS)

    Mishonov, Todor M.; Varonov, Albert M.; Maksimovski, Dejan D.; Manolev, Stojan G.; Gourev, Vassil N.; Yordanov, Vasil G.

    2017-03-01

    An experimental set-up for electrostatic measurement of {\\varepsilon }0, separate magnetostatic measurement of {μ }0 and determination of the speed of light c=1/\\sqrt{{\\varepsilon }0{μ }0} according to Maxwell’s theory with percent accuracy is described. No forces are measured with the experimental set-up, therefore there is no need for a scale, and the experiment cost of less than £20 is mainly due to the batteries used. Multiplied 137 times, this experimental set-up was given at the Fourth Open International Experimental Physics Olympiad (EPO4) and a dozen high school students performed successful experiments. The experimental set-up actually contains two different pendula for electric and magnetic measurements. In the magnetic experiment the pendulum is constituted by a magnetic coil attracted to a fixed one. In the electrostatic pendulum when the distance between the plates becomes shorter than a critical value the suspended plate catastrophically sticks to the fixed one, while in the magnetic pendulum the same occurs when the current in the coils becomes greater than a certain critical value. The basic idea of the methodology is to use the loss of stability as a tool for the determination of fundamental constants.

  17. Comparing measurement-derived (3DVH) and machine log file-derived dose reconstruction methods for VMAT QA in patient geometries.

    PubMed

    Tyagi, Neelam; Yang, Kai; Yan, Di

    2014-07-08

    The purpose of this study was to compare the measurement-derived (3DVH) dose reconstruction method with machine log file-derived dose reconstruction method in patient geometries for VMAT delivery. A total of ten patient plans were selected from a regular fractionation plan to complex SBRT plans. Treatment sites in the lung and abdomen were chosen to explore the effects of tissue heterogeneity on the respective dose reconstruction algorithms. Single- and multiple-arc VMAT plans were generated to achieve the desired target objectives. Delivered plan in the patient geometry was reconstructed by using ArcCHECK Planned Dose Perturbation (ACPDP) within 3DVH software, and by converting the machine log file to Pinnacle3 9.0 treatment plan format and recalculating dose with CVSP algorithm. In addition, delivered gantry angles between machine log file and 3DVH 4D measurement were also compared to evaluate the accuracy of the virtual inclinometer within the 3DVH. Measured ion chamber and 3DVH-derived isocenter dose agreed with planned dose within 0.4% ± 1.2% and -1.0% ± 1.6%, respectively. 3D gamma analysis showed greater than 98% between log files and 3DVH reconstructed dose. Machine log file reconstructed doses and TPS dose agreed to within 2% in PTV and OARs over the entire treatment. 3DVH reconstructed dose showed an average maximum dose difference of 3% ± 1.2% in PTV, and an average mean difference of -4.5% ± 10.5% in OAR doses. The average virtual inclinometer error (VIE) was -0.65° ± 1.6° for all patients, with a maximum error of -5.16° ± 4.54° for an SRS case. The time averaged VIE was within 1°-2°, and did not have a large impact on the overall accuracy of the estimated patient dose from ACPDP algorithm. In this study, we have compared two independent dose reconstruction methods for VMAT QA. Both methods are capable of taking into account the measurement and delivery parameter discrepancy, and display the delivered dose in CT patient geometry rather than

  18. Plate electronics

    NASA Astrophysics Data System (ADS)

    Carlowicz, Michael

    Using a Cray T3D supercomputer and a simple assumption about the physical character of Earth's mantle, a pair of researchers from the University of California at Berkeley have built a computer model that may help explain why the planet's tectonic plates look the way they do.In creating a three-dimensional numerical simulation of convection in the Earth's interior, UC researchers Hans-Peter Bunge and Mark Richards simplified their model to account for just one major physical effect: that the viscosity of the mantle increases with depth. Reviewing some recent—but not yet widely accepted—seismic data, Bunge and Richards assumed for the sake of the model that the viscosity of the mantle increases by a factor of 30 from the lithosphere to the core-mantle boundary. Relying on that assumption, the pair ran the model for nearly three weeks on a supercomputer at Los Alamos National Laboratory and found that the simulation produced an effect similar to what we see on the surface of Earth. The model produced a surface paralleling the actual width of plates and the geometry of the plate boundaries.

  19. Glass-bead peen plating

    NASA Technical Reports Server (NTRS)

    Graves, J. R.

    1974-01-01

    Peen plating of aluminum, copper, and nickel powders was investigated. Only aluminum was plated successfully within the range of peen plating conditions studied. Optimum plating conditions for aluminum were found to be: (1) bead/powder mixture containing 25 to 35% powder by weight, (2) peening intensity of 0.007A as measured by Almen strip, and (3) glass impact bead diameter of at least 297 microns (0.0117 inches) for depositing-100 mesh aluminum powder. No extensive cleaning or substrate preparation is required beyond removing loose dirt or heavy oil.

  20. Recent plate motions and crustal deformation

    SciTech Connect

    Lisowski, M. )

    1991-01-01

    Reports by U.S. workers on geodetic measurements of recent plate motions or crustal deformation published in 1987-1990 are reviewed. The review begins with global plate motions, proceeds through plate boundaries in California, Alaska, and the Pacific Northwest, and finishes with volcanic phenomena, monument stability and longevity, and GPS relative position measurements. 184 refs.

  1. Normal-Pressure Tests of Rectangular Plates

    NASA Technical Reports Server (NTRS)

    Ramberg, Walter; Mcpherson, Albert E; Levy, Samuel

    1942-01-01

    Report presents the results of normal-pressure tests made of 56 rectangular plates with clamped edges and of 5 plates with freely supported edges. Pressure was applied and the center deflection and the permanent set at the center were measured. For some of the plates, in addition, strains and contours were measured.

  2. Analysis of nanopore detector measurements using Machine-Learning methods, with application to single-molecule kinetic analysis

    PubMed Central

    Landry, Matthew; Winters-Hilt, Stephen

    2007-01-01

    Background A nanopore detector has a nanometer-scale trans-membrane channel across which a potential difference is established, resulting in an ionic current through the channel in the pA-nA range. A distinctive channel current blockade signal is created as individually "captured" DNA molecules interact with the channel and modulate the channel's ionic current. The nanopore detector is sensitive enough that nearly identical DNA molecules can be classified with very high accuracy using machine learning techniques such as Hidden Markov Models (HMMs) and Support Vector Machines (SVMs). Results A non-standard implementation of an HMM, emission inversion, is used for improved classification. Additional features are considered for the feature vector employed by the SVM for classification as well: The addition of a single feature representing spike density is shown to notably improve classification results. Another, much larger, feature set expansion was studied (2500 additional features instead of 1), deriving from including all the HMM's transition probabilities. The expanded features can introduce redundant, noisy information (as well as diagnostic information) into the current feature set, and thus degrade classification performance. A hybrid Adaptive Boosting approach was used for feature selection to alleviate this problem. Conclusion The methods shown here, for more informed feature extraction, improve both classification and provide biologists and chemists with tools for obtaining a better understanding of the kinetic properties of molecules of interest. PMID:18047711

  3. Use of projection moiré for measuring the instantaneous out-of-plane deflections of composite plates subject to bird strike

    NASA Astrophysics Data System (ADS)

    Van Paepegem, W.; Shulev, A.; Moentjens, A.; Harizanova, J.; Degrieck, J.; Sainov, V.

    2008-07-01

    For the new generation aircraft families, the use of fibre-reinforced plastics is considered for the leading edge of the wings. However, this leading edge is very prone to bird strike impact. This paper presents the use of the projection moiré technique to measure the instantaneous out-of-plane deflections of composite plates subject to bird strike. Very strict constraints with regard to (i) high-speed image acquisition, (ii) vibrations of the impact chamber, and (iii) projection and observation angles, complicated substantially the development of the set-up. Moreover, the high frame rates (12,000 fps) required a very intensive illumination. In the optimized configuration, a specially designed grating with gradually changing period is projected by means of special halide hydride lamps through one of the side windows of the impact chamber onto the composite plate riveted in a steel frame. The digital high-speed camera is mounted on the roof of the impact chamber and records through a mirror the object surface with the projected fringe pattern on it. Numerical routines based on local Fourier transform were developed to process the digital images to extract the phase and the out-of-plane displacements. The phase evaluation is possible due to the carrier frequency nature of the projected moiré pattern. This carrier frequency allows separation of the unwanted additive and multiplicative fringe pattern components in the frequency domain via the application of a proper mask. The numerical calculations were calibrated for the bird strike on an aluminum plate, where the plastic deformation could be checked after the test.

  4. Parallel Plate System for Collecting Data Used to Determine Viscosity

    NASA Technical Reports Server (NTRS)

    Kaukler, William (Inventor); Ethridge, Edwin C. (Inventor)

    2013-01-01

    A parallel-plate system collects data used to determine viscosity. A first plate is coupled to a translator so that the first plate can be moved along a first direction. A second plate has a pendulum device coupled thereto such that the second plate is suspended above and parallel to the first plate. The pendulum device constrains movement of the second plate to a second direction that is aligned with the first direction and is substantially parallel thereto. A force measuring device is coupled to the second plate for measuring force along the second direction caused by movement of the second plate.

  5. High energy X-ray diffraction measurement of residual stresses in a monolithic aluminum clad uranium–10 wt% molybdenum fuel plate assembly

    SciTech Connect

    D. W. Brown; M. A. Okuniewski; J. D. Almer; L. Balogh; B. Clausen; J. S. Okasinski; B. H. Rabin

    2013-10-01

    Residual stresses are expected in monolithic, aluminum clad uranium 10 wt% molybdenum (U–10Mo) nuclear fuel plates because of the large mismatch in thermal expansion between the two bonded materials. The full residual stress tensor of the U–10Mo foil in a fuel plate assembly was mapped with 0.1 mm resolution using high-energy (86 keV) X-ray diffraction. The in-plane stresses in the U–10Mo foil are strongly compressive, roughly -250 MPa in the longitudinal direction and -140 MPa in the transverse direction near the center of the fuel foil. The normal component of the stress is weakly compressive near the center of the foil and tensile near the corner. The disparity in the residual stress between the two in-plane directions far from the edges and the tensile normal stress suggest that plastic deformation in the aluminum cladding during fabrication by hot isostatic pressing also contributes to the residual stress field. A tensile in-plane residual stress is presumed to be present in the aluminum cladding to balance the large in-plane compressive stresses in the U–10Mo fuel foil, but cannot be directly measured with the current technique due to large grain size.

  6. SU-E-T-350: Effective Point of Measurement and Total Perturbation Correction P for Parallel-Plate Ion Chambers in High-Energy Photon Beams

    SciTech Connect

    Langner, N; Czarnecki, D; Voigts-Rhetz, P von; Zink, K

    2015-06-15

    Purpose: This paper aims to determine the effective point of measurement and the total perturbation correction p of parallel-plate chambers for clinical photon dosimetry. Methods: The effective point of measurement (EPOM) was calculated using the EGSnrc Monte Carlo code system with the EGSnrc user code egs- chamber. Depth dose curves of the ionization chambers were calculated in a water phantom for several high energy photon spectra (4, 6, 10, 15, 18 MV-X). Different normalization criterions (normalization to the maximum of the depth dose curve and normalization to the value in 10 cm depth) have been applied. The EPOM was determined by shifting the normalized depth dose curve of a small water voxel against the depth ionization curve until the disagreement (calculated by the root mean square deviation) reaches a minimum. In addition, the total perturbation correction p was calculated by the ratio of the dose to water and the product of the dose determined in the chamber and the water to air stopping power ratio. Results: The EPOM varied slightly depending on the chosen normalization criterion. For all chambers the necessary shift of the EPOM decreased linearly with increasing beam quality specifier TPR{sub 20/10}. For the Roos and NACP chamber, the results were positive suggesting that the chambers need to be shifted towards the focus. For the Markus chamber, the required shift was negative and for the Advanced Markus chamber partly negative and partly positive. The total perturbation correction p was almost independent of the depth. Only for regions below 1 cm the perturbation correction deviated significantly from unity. Conclusion: In the present study, the effective point of measurement and the total perturbation correction p was determined for four parallel-plate ionization chambers and five clinical relevant photon spectra. Applying the calculated EPOM, the residual perturbation correction p was mostly depth independent.

  7. Standardized Curriculum for Machine Tool Operation/Machine Shop.

    ERIC Educational Resources Information Center

    Mississippi State Dept. of Education, Jackson. Office of Vocational, Technical and Adult Education.

    Standardized vocational education course titles and core contents for two courses in Mississippi are provided: machine tool operation/machine shop I and II. The first course contains the following units: (1) orientation; (2) shop safety; (3) shop math; (4) measuring tools and instruments; (5) hand and bench tools; (6) blueprint reading; (7)…

  8. Workout Machine

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Orbotron is a tri-axle exercise machine patterned after a NASA training simulator for astronaut orientation in the microgravity of space. It has three orbiting rings corresponding to roll, pitch and yaw. The user is in the middle of the inner ring with the stomach remaining in the center of all axes, eliminating dizziness. Human power starts the rings spinning, unlike the NASA air-powered system. Marketed by Fantasy Factory (formerly Orbotron, Inc.), the machine can improve aerobic capacity, strength and endurance in five to seven minute workouts.

  9. Measurement of air kerma rates for 6- to 7-MeV high-energy gamma-ray field by ionisation chamber and build-up plate.

    PubMed

    Kowatari, Munehiko; Tanimura, Yoshihiko; Tsutsumi, Masahiro

    2014-12-01

    The 6- to 7-MeV high-energy gamma-ray calibration field by the (19)F(p, αγ)(16)O reaction is to be served at the Japan Atomic Energy Agency. For the determination of air kerma rates using an ionisation chamber in the 6- to 7-MeV high-energy gamma-ray field, the establishment of the charged particle equilibrium must be achieved during measurement. In addition to measurement of air kerma rates by the ionisation chamber with a thick build-up cap, measurement using the ionisation chamber and a build-up plate (BUP) was attempted, in order to directly determine air kerma rates under the condition of regular calibration for ordinary survey meters and personal dosemeters. Before measurements, Monte Carlo calculations were made to find the optimum arrangement of BUP in front of the ionisation chamber so that the charged particle equilibrium could be well established. Measured results imply that air kerma rates for the 6- to 7-MeV high-energy gamma-ray field could be directly determined under the appropriate condition using an ionisation chamber coupled with build-up materials.

  10. Using Direct Metal Deposition to Fabricate Mold Plates for an Injection Mold Machine Allowing for the Evaluation of Cost Effective Near-Sourcing Opportunities in Larger, High Volume Consumer Products

    SciTech Connect

    Duty, Chad E; Groh, Bill

    2014-10-31

    ORNL collaborated with Radio Systems Corporation to investigate additive manufacturing (AM) of mold plates for plastic injection molding by direct metal deposition. The team s modelling effort identified a 100% improvement in heat transfer through use of conformal cooling lines that could be built into the mold using a revolutionary design enabled by additive manufacturing. Using the newly installed laser deposition system at the ORNL Manufacturing Demonstration Facility (MDF) a stainless steel mold core was printed.

  11. A robust hybrid model integrating enhanced inputs based extreme learning machine with PLSR (PLSR-EIELM) and its application to intelligent measurement.

    PubMed

    He, Yan-Lin; Geng, Zhi-Qiang; Xu, Yuan; Zhu, Qun-Xiong

    2015-09-01

    In this paper, a robust hybrid model integrating an enhanced inputs based extreme learning machine with the partial least square regression (PLSR-EIELM) was proposed. The proposed PLSR-EIELM model can overcome two main flaws in the extreme learning machine (ELM), i.e. the intractable problem in determining the optimal number of the hidden layer neurons and the over-fitting phenomenon. First, a traditional extreme learning machine (ELM) is selected. Second, a method of randomly assigning is applied to the weights between the input layer and the hidden layer, and then the nonlinear transformation for independent variables can be obtained from the output of the hidden layer neurons. Especially, the original input variables are regarded as enhanced inputs; then the enhanced inputs and the nonlinear transformed variables are tied together as the whole independent variables. In this way, the PLSR can be carried out to identify the PLS components not only from the nonlinear transformed variables but also from the original input variables, which can remove the correlation among the whole independent variables and the expected outputs. Finally, the optimal relationship model of the whole independent variables with the expected outputs can be achieved by using PLSR. Thus, the PLSR-EIELM model is developed. Then the PLSR-EIELM model served as an intelligent measurement tool for the key variables of the Purified Terephthalic Acid (PTA) process and the High Density Polyethylene (HDPE) process. The experimental results show that the predictive accuracy of PLSR-EIELM is stable, which indicate that PLSR-EIELM has good robust character. Moreover, compared with ELM, PLSR, hierarchical ELM (HELM), and PLSR-ELM, PLSR-EIELM can achieve much smaller predicted relative errors in these two applications.

  12. The effect orientation of features in reconstructed atom probe data on the resolution and measured composition of T1 plates in an A2198 aluminium alloy.

    PubMed

    Mullin, Maria A; Araullo-Peters, Vicente J; Gault, Baptiste; Cairney, Julie M

    2015-12-01

    Artefacts in atom probe tomography can impact the compositional analysis of microstructure in atom probe studies. To determine the integrity of information obtained, it is essential to understand how the positioning of features influences compositional analysis. By investigating the influence of feature orientation within atom probe data on measured composition in microstructural features within an AA2198 Al alloy, this study shows differences in the composition of T1 (Al2CuLi) plates that indicates imperfections in atom probe reconstructions. The data fits a model of an exponentially-modified Gaussian that scales with the difference in evaporation field between solutes and matrix. This information provides a guide for obtaining the most accurate information possible.

  13. Wacky Machines

    ERIC Educational Resources Information Center

    Fendrich, Jean

    2002-01-01

    Collectors everywhere know that local antique shops and flea markets are treasure troves just waiting to be plundered. Science teachers might take a hint from these hobbyists, for the next community yard sale might be a repository of old, quirky items that are just the things to get students thinking about simple machines. By introducing some…

  14. Optimisation of output factor measurements using the Magic Plate 512 silicon dosimeter array in small megavoltage photon fields

    NASA Astrophysics Data System (ADS)

    Utitsarn, K.; Alrowaili, Z. A.; Stansook, N.; Lerch, M.; Petasecca, M.; Carolan, M.; Rosenfeld, A.

    2017-01-01

    We evaluate the impact of an air gap and optimization of this air gap for the MP512 silicon detector array when operated in dosimetry mode for small photon field measurements in solid water. We present output factor measurements for 6MV and 10 MV photon beams with the square field sizes ranging from 0.5 to 10 cm2. The size of the air gap above the MP512 detector was changed from 0.5, 1.0, 1.2, 2.0 and 2.6 mm. We compare the output factors measurements of the MP512 with EBT3 film and the MOSkin dosimeter. For the two photon energies investigated, we find that the output factor measured by the MP512 reduce with increasing air gap and reducing of field size. The reduction in output factor is most pronounced for the 0.5 and 1 cm2 field sizes. The air gap of 0.5 mm and 1.2 mm showed good agreement with the EBT3 film and MOSkin output factor for 6 and 10 MV photon fields, respectively. The negligible effect on dosimetry for the field sizes larger than 4x4 cm2 demonstrates that the electronic disequilibrium caused by small air gap only influences the dosimetry measurements for small fields. The study shows that the output factor reduction is enhanced by increasing of air gap and demonstrates that the optimal air gap for the MP512 at 6 and 10 MV photon fields is 0.5mm.

  15. Aerodynamic seals for rotary machine

    DOEpatents

    Bidkar, Rahul Anil; Cirri, Massimiliano; Thatte, Azam Mihir; Williams, John Robert

    2016-02-09

    An aerodynamic seal assembly for a rotary machine includes multiple sealing device segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the segments includes a shoe plate with a forward-shoe section and an aft-shoe section having multiple labyrinth teeth therebetween facing the rotor. The sealing device segment also includes multiple flexures connected to the shoe plate and to a top interface element, wherein the multiple flexures are configured to allow the high pressure fluid to occupy a forward cavity and the low pressure fluid to occupy an aft cavity. Further, the sealing device segments include a secondary seal attached to the top interface element at one first end and positioned about the flexures and the shoe plate at one second end.

  16. Machine characterization based on an abstract high-level language machine

    NASA Technical Reports Server (NTRS)

    Saavedra-Barrera, Rafael H.; Smith, Alan Jay; Miya, Eugene

    1989-01-01

    Measurements are presented for a large number of machines ranging from small workstations to supercomputers. The authors combine these measurements into groups of parameters which relate to specific aspects of the machine implementation, and use these groups to provide overall machine characterizations. The authors also define the concept of pershapes, which represent the level of performance of a machine for different types of computation. A metric based on pershapes is introduced that provides a quantitative way of measuring how similar two machines are in terms of their performance distributions. The metric is related to the extent to which pairs of machines have varying relative performance levels depending on which benchmark is used.

  17. Measurement of pH of rice wines using Vis/NIR spectroscopy and least squares-support vector machine

    NASA Astrophysics Data System (ADS)

    He, Yong; Liu, Fei; Wang, Li

    2007-12-01

    Visible and near infrared (Vis/NIR) transmission spectroscopy and a hybrid chemometrics method were applied to determine the pH of rice wines. A spectroradiometer with a wavelength region of 325-1075 nm was used for spectral scanning. The calibration set was composed of 240 samples and 60 samples were used in the validation set. The smoothing way of Savitzky-Golay and standard normal variate (SNV) were used as data pre-processing methods. Principal components analysis (PCA) was employed to extract the principal components (PCs) which were used as the inputs of Least squares-support vector machine (LS-SVM) model. Then LS-SVM with radial basis function (RBF) kernel function was applied to build the regression model with a comparison of partial least squares (PLS) regression. The correlation coefficient (r), root mean square error of prediction (RMSEP) and bias of LS-SVM were 0.964, 2.62x10 -4 and 8.83x10 -4, respectively. Significant wavelengths for pH were proposed according to x-loading weights. The results indicated that Vis/NIR spectroscopy with the combination of LS-SVM could be utilized as an alternative way for the determination pH of rice wines.

  18. Contact-spring forming machine for flat conductor cable receptacles

    NASA Technical Reports Server (NTRS)

    Angele, W.; Martineck, H. G.

    1968-01-01

    Machine tool produces beryllium-copper contact springs for FCC /flat conductor cable/ feed-through receptacles. The springs are heat-treated and plated to impart the required electrical contact properties.

  19. Machine Learning

    NASA Astrophysics Data System (ADS)

    Hoffmann, Achim; Mahidadia, Ashesh

    The purpose of this chapter is to present fundamental ideas and techniques of machine learning suitable for the field of this book, i.e., for automated scientific discovery. The chapter focuses on those symbolic machine learning methods, which produce results that are suitable to be interpreted and understood by humans. This is particularly important in the context of automated scientific discovery as the scientific theories to be produced by machines are usually meant to be interpreted by humans. This chapter contains some of the most influential ideas and concepts in machine learning research to give the reader a basic insight into the field. After the introduction in Sect. 1, general ideas of how learning problems can be framed are given in Sect. 2. The section provides useful perspectives to better understand what learning algorithms actually do. Section 3 presents the Version space model which is an early learning algorithm as well as a conceptual framework, that provides important insight into the general mechanisms behind most learning algorithms. In section 4, a family of learning algorithms, the AQ family for learning classification rules is presented. The AQ family belongs to the early approaches in machine learning. The next, Sect. 5 presents the basic principles of decision tree learners. Decision tree learners belong to the most influential class of inductive learning algorithms today. Finally, a more recent group of learning systems are presented in Sect. 6, which learn relational concepts within the framework of logic programming. This is a particularly interesting group of learning systems since the framework allows also to incorporate background knowledge which may assist in generalisation. Section 7 discusses Association Rules - a technique that comes from the related field of Data mining. Section 8 presents the basic idea of the Naive Bayesian Classifier. While this is a very popular learning technique, the learning result is not well suited for

  20. A new treadmill-type motorized walking belt machine for video recording of the rat's gait and sciatic functional index measurement. A comparative study with other methods.

    PubMed

    Monte-Raso, Vanessa Vilela; Barbieri, Giuliano; Mazzer, Nilton; Fonseca, Marisa de Cássia Registro; Barbieri, Cláudio Henrique

    2010-05-30

    The sciatic functional index (SFI) is a remarkable tool to assess dysfunction and functional recovery of the sciatic nerve of rats. Usually measured on hind foot imprints on paper, a new method is now being proposed, by direct analysis of video recorded foot sole images obtained with a treadmill-type walking belt machine functioning with gait speed control (G1). Results were compared with the SFI measured on imprints on paper (G2) and on video recorded foot sole images obtained with a static see-through runway (G3). The right sciatic nerve of 19 adult female Wistar rats was crushed by the application of a controlled load. Impressions/images obtained both preoperatively and at weekly intervals for eight consecutive postoperative weeks were digitized, stored and analyzed in a computer loaded with specific software, the SFI being automatically calculated after measuring the appropriate parameters. SFI differed significantly between G1 and G2 and G1 and G3 (p<0.05), but not between G2 and G3 (p>0.05) during the first and second postoperative weeks, nonsignificant differences (p>0.05) being observed for any comparison between groups during the third through eighth postoperative weeks. We conclude that the three methods yielded equivalent results from the third week onward, but both video recording methods (G2 and G3) permitted a more adequate early evaluation (first and second weeks), since the SFI parameters were more easily identifiable. Images obtained with the walking belt machine are more uniform and sharper, thus contributing to reduce the influence of biases observed with imprints on paper.

  1. Oxygen transfer phenomena in 48-well microtiter plates: determination by optical monitoring of sulfite oxidation and verification by real-time measurement during microbial growth.

    PubMed

    Kensy, Frank; Zimmermann, Hartmut F; Knabben, Ingo; Anderlei, Tibor; Trauthwein, Harald; Dingerdissen, Uwe; Büchs, Jochen

    2005-03-20

    Oxygen limitation is one of the most frequent problems associated with the application of shaking bioreactors. The gas-liquid oxygen transfer properties of shaken 48-well microtiter plates (MTPs) were analyzed at different filling volumes, shaking diameters, and shaking frequencies. On the one hand, an optical method based on sulfite oxidation was used as a chemical model system to determine the maximum oxygen transfer capacity (OTR(max)). On the other hand, the Respiration Activity Monitoring System (RAMOS) was applied for online measurement of the oxygen transfer rate (OTR) during growth of the methylotropic yeast Hansenula polymorpha. A proportionality constant between the OTR(max) of the biological system and the OTR(max) of the chemical system were indicated from these data, offering the possibility to transform the whole set of chemical data to biologically relevant conditions. The results exposed "out of phase" shaking conditions at a shaking diameter of 1 mm, which were confirmed by theoretical consideration with the phase number (Ph). At larger shaking diameters (2-50 mm) the oxygen transfer rate in MTPs shaken at high frequencies reached values of up to 0.28 mol/L/h, corresponding to a volumetric mass transfer coefficient (k(L)a) of 1,600 1/h. The specific mass transfer area (a) increases exponentially with the shaking frequency up to values of 2,400 1/m. On the contrary, the mass transfer coefficient (k(L)) is constant at a level of about 0.15 m/h over a wide range of shaking frequencies and shaking diameters. However, at high shaking frequencies, when the complete liquid volume forms a thin film on the cylindric wall of the well, the mass transfer coefficient (k(L)) increases linearly to values of up to 0.76 m/h. Essentially, the present investigation demonstrates that the 48-well plate outperforms the 96-well MTP and shake flasks at widely used operating conditions with respect to oxygen supply. The 48-well plates emerge, therefore, as an excellent

  2. Electrochemical Assay of Gold-Plating Solutions

    NASA Technical Reports Server (NTRS)

    Chiodo, R.

    1982-01-01

    Gold content of plating solution is assayed by simple method that required only ordinary electrochemical laboratory equipment and materials. Technique involves electrodeposition of gold from solution onto electrode, the weight gain of which is measured. Suitable fast assay methods are economically and practically necessary in electronics and decorative-plating industries. If gold content in plating bath is too low, poor plating may result, with consequent economic loss to user.

  3. Charging machine

    DOEpatents

    Medlin, John B.

    1976-05-25

    A charging machine for loading fuel slugs into the process tubes of a nuclear reactor includes a tubular housing connected to the process tube, a charging trough connected to the other end of the tubular housing, a device for loading the charging trough with a group of fuel slugs, means for equalizing the coolant pressure in the charging trough with the pressure in the process tubes, means for pushing the group of fuel slugs into the process tube and a latch and a seal engaging the last object in the group of fuel slugs to prevent the fuel slugs from being ejected from the process tube when the pusher is removed and to prevent pressure liquid from entering the charging machine.

  4. Induction machine

    DOEpatents

    Owen, Whitney H.

    1980-01-01

    A polyphase rotary induction machine for use as a motor or generator utilizing a single rotor assembly having two series connected sets of rotor windings, a first stator winding disposed around the first rotor winding and means for controlling the current induced in one set of the rotor windings compared to the current induced in the other set of the rotor windings. The rotor windings may be wound rotor windings or squirrel cage windings.

  5. Development and validation of capabilities to measure thermal properties of layered monolithic U-Mo alloy plate-type fuel

    SciTech Connect

    Burkes, Douglas; Casella, Andrew M.; Buck, Edgar C.; Casella, Amanda J.; Edwards, Matthew K.; MacFarlan, Paul J.; Pool, Karl N.; Smith, Frances N.; Steen, Franciska H.

    2014-07-19

    The uranium-molybdenum (U-Mo) alloy in a monolithic form has been proposed as one fuel design capable of converting some of the world’s highest power research reactors from the use of high enriched uranium (HEU) to low enriched uranium (LEU). One aspect of the fuel development and qualification process is to demonstrate appropriate understanding of thermal conductivity behavior of the fuel system as a function of temperature and expected irradiation conditions. The purpose of this paper is to verify and validate the functionality of equipment methods installed in hot cells for eventual measurements on irradiated uranium-molybdenum (U-Mo) monolithic fuel specimens, procedures to operate the equipment, and models to extract the desired thermal properties. The results presented here demonstrate the adequacy of the equipment, procedures and models that have been developed for this purpose based on measurements conducted on surrogate depleted uranium-molybdenum (DU-Mo) alloy samples containing a zirconium diffusion barrier and clad in aluminum alloy 6061 (AA6061). The results are in excellent agreement with thermal property data reported in the literature for similar U-Mo alloys as a function of temperature.

  6. Machine vision

    SciTech Connect

    Horn, D.

    1989-06-01

    To keep up with the speeds of modern production lines, most machine vision applications require very powerful computers (often parallel-processing machines), which process millions of points of data in real time. The human brain performs approximately 100 billion logical floating-point operations each second. That is 400 times the speed of a Cray-1 supercomputer. The right software must be developed for parallel-processing computers. The NSF has awarded Rensselaer Polytechnic Institute (Troy, N.Y.) a $2 million grant for parallel- and image-processing software research. Over the last 15 years, Rensselaer has been conducting image-processing research, including work with high-definition TV (HDTV) and image coding and understanding. A similar NSF grant has been awarded to Michigan State University (East Lansing, Mich.) Neural networks are supposed to emulate human learning patterns. These networks and their hardware implementations (neurocomputers) show a great deal of promise for machine vision systems because they allow the systems to understand the use sensory data input more effectively. Neurocomputers excel at pattern-recognition tasks when input data are fuzzy or the vision algorithm is not optimal and is difficult to ascertain.

  7. Second catalog of interferometric measurements of binary stars (McAlister and Hartkopf 1988): Documentation for the machine-readable version

    NASA Technical Reports Server (NTRS)

    Warren, Wayne H., Jr.

    1989-01-01

    The machine-readable version of the catalog, as it is currently being distributed from the Astronomical Data Center, is described. The catalog is a compilation of measurements of binary- and multiple-star systems obtained by speckle interferometric techniques; this version supersedes a previous edition of the catalog published in 1985. Stars that have been examined for multiplicity with negative results are included, in which case upper limits for the separation are given. The second version is expanded from the first in that a file of newly resolved systems and six cross-index files of alternate designations are included. The data file contains alternate identifications for the observed systems, epochs of observation, reported errors in position angles and separation, and bibliographical references.

  8. Development of flat - plate solar plate collector - evaporator. Summary report

    SciTech Connect

    Abramzon, B.; Yaron, I.

    1981-11-01

    In the present study the thermal performance of a flat plate solar collector is analyzed theoretically for the case in which the working fluid may undergo a phase change within the tubes of the collector. In addition to the common domestic applications, such a collector - evaporator may be used as a generator of vapors for the production of mechanical or electrical energy, e.g. solar water pumps, solar power stations, etc., as well as for solar - powered absorption refrigeration machines, distillation installations, etc.

  9. Computational work and time on finite machines.

    NASA Technical Reports Server (NTRS)

    Savage, J. E.

    1972-01-01

    Measures of the computational work and computational delay required by machines to compute functions are given. Exchange inequalities are developed for random access, tape, and drum machines to show that product inequalities between storage and time, number of drum tracks and time, number of bits in an address and time, etc., must be satisfied to compute finite functions on bounded machines.

  10. Joint measurement of the atmospheric muon flux through the Puy de Dome volcano with plastic scintillators and Resistive Plate Chambers detectors

    SciTech Connect

    Ambrosino, F.; Anastasio, A.; Bross, A.; Bene, S.; Bonechi, L.; Carloganu, C.; Cimmino, L.; Combaret, Ch.; Durand, S.; Fehr, F.; Gailler, L.; Labazuy, Ph.; Laktineh, I.; Masone, V.; Miallier, D.; Mori, N.; Niess, V.; Pla-Dalmau, A.; Portal, A.; Rubinov, P.; Saracino, G.; Scarlini, E.; Strolin, P.; Vulpescu, B.

    2015-11-14

    The muographic imaging of volcanoes relies on the measured transmittance of the atmospheric muon flux through the target. An important bias affecting the result comes from background contamination mimicking a higher transmittance. The MU-RAY and TOMUVOL collaborations measured independently in 2013 the atmospheric muon flux transmitted through the Puy de Dôme volcano using their early prototype detectors, based on plastic scintillators and on Glass Resistive Plate Chambers, respectively. These detectors had three (MU-RAY) or four (TOMUVOL) detection layers of 1 m2 each, tens (MU-RAY) or hundreds (TOMUVOL) of nanosecond time resolution, a few millimeter position resolution, an energy threshold of few hundreds MeV, and no particle identification capabilities. The prototypes were deployed about 1.3 km away from the summit, where they measured, behind rock depths larger than 1000 m, remnant fluxes of 1.83±0.50(syst)±0.07(stat) m–2 d–1 deg–2 (MU-RAY) and 1.95±0.16(syst)±0.05(stat) m–2 d–1 deg–2 (TOMUVOL), that roughly correspond to the expected flux of high-energy atmospheric muons crossing 600 meters water equivalent (mwe) at 18° elevation. This implies that imaging depths larger than 500 mwe from 1 km away using such prototype detectors suffer from an overwhelming background. These measurements confirm that a new generation of detectors with higher momentum threshold, time-of-flight measurement, and/or particle identification is needed. As a result, the MU-RAY and TOMUVOL collaborations expect shortly to operate improved detectors, suitable for a robust muographic imaging of kilometer-scale volcanoes.

  11. Joint measurement of the atmospheric muon flux through the Puy de Dome volcano with plastic scintillators and Resistive Plate Chambers detectors

    DOE PAGES

    Ambrosino, F.; Anastasio, A.; Bross, A.; ...

    2015-11-14

    The muographic imaging of volcanoes relies on the measured transmittance of the atmospheric muon flux through the target. An important bias affecting the result comes from background contamination mimicking a higher transmittance. The MU-RAY and TOMUVOL collaborations measured independently in 2013 the atmospheric muon flux transmitted through the Puy de Dôme volcano using their early prototype detectors, based on plastic scintillators and on Glass Resistive Plate Chambers, respectively. These detectors had three (MU-RAY) or four (TOMUVOL) detection layers of 1 m2 each, tens (MU-RAY) or hundreds (TOMUVOL) of nanosecond time resolution, a few millimeter position resolution, an energy threshold ofmore » few hundreds MeV, and no particle identification capabilities. The prototypes were deployed about 1.3 km away from the summit, where they measured, behind rock depths larger than 1000 m, remnant fluxes of 1.83±0.50(syst)±0.07(stat) m–2 d–1 deg–2 (MU-RAY) and 1.95±0.16(syst)±0.05(stat) m–2 d–1 deg–2 (TOMUVOL), that roughly correspond to the expected flux of high-energy atmospheric muons crossing 600 meters water equivalent (mwe) at 18° elevation. This implies that imaging depths larger than 500 mwe from 1 km away using such prototype detectors suffer from an overwhelming background. These measurements confirm that a new generation of detectors with higher momentum threshold, time-of-flight measurement, and/or particle identification is needed. As a result, the MU-RAY and TOMUVOL collaborations expect shortly to operate improved detectors, suitable for a robust muographic imaging of kilometer-scale volcanoes.« less

  12. Potential for optimizing the Higgs boson C P measurement in H →τ τ decays at the LHC including machine learning techniques

    NASA Astrophysics Data System (ADS)

    Józefowicz, R.; Richter-Was, E.; Was, Z.

    2016-11-01

    We investigate the potential for measuring the C P state of the Higgs boson in H →τ τ decays with consecutive τ -lepton decays in the channels: τ±→ρ±ντ and τ±→a1±ντ combined. Subsequent decays ρ±→π±π0, a1±→ρ0π± and ρ0→π+π- are taken into account. We will explore extensions of the method, where the acoplanarity angle for the planes build on the visible decay products, π±π0 of τ±→π±π0ντ, was used. The angle is sensitive to transverse spin correlations, thus to parity. We show that in the case of the cascade decays of τ →a1ν , information on the C P state of Higgs can be extracted from the acoplanarity angles as well. Because in the cascade decay a1±→ρ0π± , ρ0→π+π- up to four planes can be defined, up to 16 distinct acoplanarity angles are available for H →τ τ →a1+a1-ν ν decays. These acoplanarities carry in part supplementary but also correlated information. It is thus cumbersome to evaluate an overall sensitivity. We investigate the sensitivity potential of such analysis, by developing and applying machine learning techniques. We quantify possible improvements when multidimensional phase space of outgoing decay products directions is used, instead of one-dimensional projections i.e. the acoplanarity angles. We do not take into account ambiguities resulting from detector uncertainties or background contamination; we concentrate on the usefulness of machine learning methods and τ →3 π ν decays for Higgs boson parity measurement.

  13. Simulating wave-turbulence on thin elastic plates with arbitrary boundary conditions

    NASA Astrophysics Data System (ADS)

    van Rees, Wim M.; Mahadevan, L.

    2016-11-01

    The statistical characteristics of interacting waves are described by the theory of wave turbulence, with the study of deep water gravity wave turbulence serving as a paradigmatic physical example. Here we consider the elastic analog of this problem in the context of flexural waves arising from vibrations of a thin elastic plate. Such flexural waves generate the unique sounds of so-called thunder machines used in orchestras - thin metal plates that make a thunder-like sound when forcefully shaken. Wave turbulence in elastic plates is typically investigated numerically using spectral simulations with periodic boundary conditions, which are not very realistic. We will present the results of numerical simulations of the dynamics of thin elastic plates in physical space, with arbitrary shapes, boundary conditions, anisotropy and inhomogeneity, and show first results on wave turbulence beyond the conventionally studied rectangular plates. Finally, motivated by a possible method to measure ice-sheet thicknesses in the open ocean, we will further discuss the behavior of a vibrating plate when floating on an inviscid fluid.

  14. Measuring laser power as a force: a new paradigm to accurately monitor optical power during laser-based machining operations

    NASA Astrophysics Data System (ADS)

    Williams, Paul; Simonds, Brian; Sowards, Jeffrey; Hadler, Joshua

    2016-03-01

    In laser manufacturing operations, accurate measurement of laser power is important for product quality, operational repeatability, and process validation. Accurate real-time measurement of high-power lasers, however, is difficult. Typical thermal power meters must absorb all the laser power in order to measure it. This constrains power meters to be large, slow and exclusive (that is, the laser cannot be used for its intended purpose during the measurement). To address these limitations, we have developed a different paradigm in laser power measurement where the power is not measured according to its thermal equivalent but rather by measuring the laser beam's momentum (radiation pressure). Very simply, light reflecting from a mirror imparts a small force perpendicular to the mirror which is proportional to the optical power. By mounting a high-reflectivity mirror on a high-sensitivity force transducer (scale), we are able to measure laser power in the range of tens of watts up to ~ 100 kW. The critical parameters for such a device are mirror reflectivity, angle of incidence, and scale sensitivity and accuracy. We will describe our experimental characterization of a radiation-pressure-based optical power meter. We have tested it for modulated and CW laser powers up to 92 kW in the laboratory and up to 20 kW in an experimental laser welding booth. We will describe present accuracy, temporal response, sources of measurement uncertainty, and hurdles which must be overcome to have an accurate power meter capable of routine operation as a turning mirror within a laser delivery head.

  15. Compressive strength of damaged and repaired composite plates

    NASA Technical Reports Server (NTRS)

    Finn, Scott R.; Springer, George S.

    1992-01-01

    Tests were performed assessing the effectiveness of repair in restoring the mechanical properties of damaged, solid composite plates made of Fiberite T300/976 graphite-epoxy. Some (75%) or all (100%) of the damaged zone was cut out, and the plate was repaired by plugging and patching the hole. The effectiveness of the repair was evaluated by measuring the compressive strengths of undamaged plates, damaged plates with no cutout, damaged plates with a cutout, and plates that had been repaired.

  16. Instrumentation, Data Acquisition and Controls for Temperature Measurement of Cold Surfaces at 4.5 K and 80 K of SST-1 Machine

    NASA Astrophysics Data System (ADS)

    Panchal, P.; Sonara, D.; Sarkar, B.; Bhattacharya, R.; Panchal, R.; Patel, R.; Tank, J.; Singh, M.; Sahu, A. K.; Saxena, Y. C.

    2008-03-01

    Two-temperature regimes have been envisaged for the SST-1 machine, 80 K on the thermal shield and 4.5 K on the superconducting magnet system. The aim of temperature measurement is two folds (i) to monitor the temperature distribution as well as process parameters (ii) to achieve controlled cool down from 300 K to 4.5 K and 80 K. Temperature sensors have been mounted on cold surfaces at required locations to ease the operation during cool down and steady state. Techniques employed for temperature measurement and controls are based on continuous resistance measurement. Cernox™ sensors (Lakeshore made) and PT-102 have been used for the temperature measurement at 4.5 K and 80 K surfaces respectively. The data acquisition system (DAS) has been indigenously developed using 4-20 mA current loop temperature transmitter, which provided better functioning in terms of flexibility. The control functioning has been designed and developed using programmable logic controller with direct interfacing of the transmitter. The temperature data is obtained at the supervisory control and data acquisition of dedicated node. The developed DAS has been found to be very reliable and satisfactory.

  17. Calibration For On-Machine Inspections

    NASA Technical Reports Server (NTRS)

    Haymaker, Carlton L., Jr.

    1990-01-01

    Permanent calibration setup on numerically-controlled machine tool enables fast and reliable calibration of automated probes for inspection of workpieces while still mounted on machine. Setup includes one or more artifacts, dimensions and locations known precisely and stored in memory of computer controlling machine. Before probes used to inspect newly machined part, used to check artifacts. Probe measurements compared with values in memory to determine whether probe readings need adjustment.

  18. THE IMPACT OF THE SPECTRAL RESPONSE OF AN ACHROMATIC HALF-WAVE PLATE ON THE MEASUREMENT OF THE COSMIC MICROWAVE BACKGROUND POLARIZATION

    SciTech Connect

    Bao, C.; Gold, B.; Hanany, S.; Baccigalupi, C.; Leach, S.; Didier, J.; Johnson, B. R.; Miller, A.; Jaffe, A.; O'Dea, D.; Matsumura, T.

    2012-03-10

    We study the impact of the spectral dependence of the linear polarization rotation induced by an achromatic half-wave plate on measurements of cosmic microwave background polarization in the presence of astrophysical foregrounds. We focus on the systematic effects induced on the measurement of inflationary gravitational waves by uncertainties in the polarization and spectral index of Galactic dust. We find that for the experimental configuration and noise levels of the balloon-borne EBEX experiment, which has three frequency bands centered at 150, 250, and 410 GHz, a crude dust subtraction process mitigates systematic effects to below detectable levels for 10% polarized dust and tensor-to-scalar ratio of as low as r = 0.01. We also study the impact of uncertainties in the spectral response of the instrument. With a top-hat model of the spectral response for each band, characterized by band center and bandwidth, and with the same crude dust subtraction process, we find that these parameters need to be determined to within 1 and 0.8 GHz at 150 GHz; 9 and 2.0 GHz at 250 GHz; and 20 and 14 GHz at 410 GHz, respectively. The approach presented in this paper is applicable to other optical elements that exhibit polarization rotation as a function of frequency.

  19. The reliability of linear position transducer and force plate measurement of explosive force-time variables during a loaded jump squat in elite athletes.

    PubMed

    Hansen, Keir T; Cronin, John B; Newton, Michael J

    2011-05-01

    The best method of assessing muscular force qualities during isoinertial stretch shorten cycle lower body movements remains a subject of much debate. This study had 2 purposes: Firstly, to calculate the interday reliability of peak force (PF) measurement and a variety of force-time measures, and, secondly, to compare the reliability of the 2 most common technologies for measuring force during loaded jump squats, the linear position transducer (PT), and the force plate (FP). Twenty-five male elite level rugby union players performed 3 rebound jump squats with a 40-kg external load on 2 occasions 1 week apart. Vertical ground reaction forces (GRFs) were directly measured via an FP, and force was differentiated from position data collected using a PT. From these data, a number of force-time variables were calculated for both the FP and PT. Intraclass correlation coefficient (ICC), coefficient of variation (CV), and percent change in the mean were used as measures of between-session reliability. Additionally, Pearson's product moment correlation coefficients were used to investigate intercorrelations between variables and technologies. Both FP and PT were found to be a reliable means of measuring PF (ICC = 0.88-0.96, CV = 2.3-4.8%), and the relationship between the 2 technologies was very high and high for days 1 and 2, respectively (r = 0.67-0.88). Force-time variables calculated from FP data tended to have greater relative and absolute consistency (ICC = 0.70-0.96, CV = 5.1-51.8%) than those calculated from differentiated PT data (ICC = 0.18-0.95, CV = 7.7-93.6%). Intercorrelations between variables ranged from trivial to practically perfect (r = 0.00-1.00). It was concluded that PF can be measured reliably with both FP and PT technologies, and these measurements are related. A number of force-time values can also be reliably calculated via the use of GRF data. Although some of these force-time variables can be reliably calculated using position data, variation of

  20. Corrugated cover plate for flat plate collector

    DOEpatents

    Hollands, K. G. Terry; Sibbitt, Bruce

    1978-01-01

    A flat plate radiant energy collector is providing having a transparent cover. The cover has a V-corrugated shape which reduces the amount of energy reflected by the cover away from the flat plate absorber of the collector.

  1. WEST END OF SOUTH FACADE OF MACHINE SHOP No. 1. ...

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

    WEST END OF SOUTH FACADE OF MACHINE SHOP No. 1. BRICK SECTION ON THE LEFT IS THE FORMER OFFICE OF THE ARMOR PLATE DIVISION BUILT IN 1899 - U.S. Steel Homestead Works, Machine Shop No. 1, Along Monongahela River, Homestead, Allegheny County, PA

  2. HUNTER 20 MATCHPLATE MOLDING MACHINE, OPERATING THE SAME AS THE ...

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

    HUNTER 20 MATCHPLATE MOLDING MACHINE, OPERATING THE SAME AS THE HUNTER 10 AND OTHER HUNTER 20 COMPRESSES BOTH MOLD HALVES OVER A DOUBLE-SIDED MATCH PLATE PATTERN. DENNIS GRAY TESTS A MOLD'S HARDNESS TO ENSURE SAND MIXTURE AND MACHINE COMPRESSIBILITY ARE CORRECT. - Southern Ductile Casting Company, Casting, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

  3. Machinability of Stellite 6 hardfacing

    NASA Astrophysics Data System (ADS)

    Benghersallah, M.; Boulanouar, L.; Le Coz, G.; Devillez, A.; Dudzinski, D.

    2010-06-01

    This paper reports some experimental findings concerning the machinability at high cutting speed of nickel-base weld-deposited hardfacings for the manufacture of hot tooling. The forging work involves extreme impacts, forces, stresses and temperatures. Thus, mould dies must be extremely resistant. The aim of the project is to create a rapid prototyping process answering to forging conditions integrating a Stellite 6 hardfacing deposed PTA process. This study talks about the dry machining of the hardfacing, using a two tips machining tool and a high speed milling machine equipped by a power consumption recorder Wattpilote. The aim is to show the machinability of the hardfacing, measuring the power and the tip wear by optical microscope and white light interferometer, using different strategies and cutting conditions.

  4. Growth Plate Fractures

    MedlinePlus

    .org Growth Plate Fractures Page ( 1 ) The bones of children and adults share many of the same risks for injury. But because they ... to a unique injury called a growth plate fracture. Growth plates are areas of cartilage located near ...

  5. An automated 96-well-plate loader for FACScan.

    PubMed

    Illges, H

    1999-01-01

    Staining multiple samples for data acquisition with a flow cytometer is done in 96-well plates to save time and make large data assessment in one working day possible. However, the inability of the FACScan to take up the samples from 96-well plates is a major drawback. In order to avoid the individual transfer of samples to tubes, we have developed a system, which allows using the FACScan with 96-well plates. The machine consists of a programmable control module and a loader which moves the 96-well plate in 3 axis well by well along the sample collector. The machine is equipped with a wash buffer tank to avoid cross contamination of samples and a shaking option to avoid sedimentation of cells during acquisition. The machine can be further developed into a full automatic loader if connected to the FACS Station. In 24 hours about 7,000 samples with 10,000 cells each can be acquired.

  6. The Influence of Selected Parameters on Evaluation of the Geometrical Shape Deviation - Cylindricity in 3D Measuring Machine Workspace

    NASA Astrophysics Data System (ADS)

    Drbúl, Mário; Šajgalík, Michal; Litvaj, lvan; Babík, Ondrej

    2016-12-01

    Each part as a final product and its surface is composed of various geometric elements, although at first glance seem as smooth and shiny. During the manufacturing process, there is a number of influences (e.g. selected manufacturing technology, production process, human factors, the strategy of measurement, scanning speed, shape of the measurement contact tip, temperature, or the surface tension and the like), which hinder the production of component with ideally shaped elements. From the economic and design point of view (in accordance with determined GPS standards), there is necessary fast and accurate analyze and evaluate these elements. Presented article deals with the influence of scanning speed and measuring strategy for assessment of shape deviations.

  7. TEMPO machine

    SciTech Connect

    Rohwein, G.J.; Lancaster, K.T.; Lawson, R.N.

    1986-06-01

    TEMPO is a transformer powered megavolt pulse generator with an output pulse of 100 ns duration. The machine was designed for burst mode operation at pulse repetition rates up to 10 Hz with minimum pulse-to-pulse voltage variations. To meet the requirement for pulse duration a nd a 20-..omega.. output impedance within reasonable size constraints, the pulse forming transmission line was designed as two parallel water-insulated, strip-type Blumleins. Stray capacitance and electric fields along the edges of the line elements were controlled by lining the tank with plastic sheet.

  8. SU-E-T-271: Direct Measurement of Tenth Value Layer Thicknesses for High Density Concretes with a Clinical Machine

    SciTech Connect

    Tanny, S; Parsai, E; Harrell, D; Noller, J; Chopra, M

    2015-06-15

    Purpose: Use of high density concrete for radiation shielding is increasing, trading cost for space savings associated with the reduced tenth value layer (TVL). Precise information on the attenuation properties of high-density concretes is not readily present in the literature. A simple approximation is to scale the TVLs from NCRP 151 according relative increase in density. Here we present measured TVLs for heavy concretes of various densities using a built-in shielding test port. Methods: Concrete densities tested range from 2.35 g cc{sup −1} (147 pcf) to 5.6 g cc{sup −1} (350 pcf). Measurements were taken using 6MV, 6FFF, and 10FFF on a Varian Truebeam linear accelerator. Field sizes of 4x4, 9x9 and 30x30 cm{sup 2} were measured. A PTW 31013 Farmer chamber with a buildup cap was positioned 5.5 m from isocenter along the beam CAX. Concrete thicknesses were incremented in 5 cm intervals. Comparison TVLs were determined by scaling the NCRP 151 TVLs by the density ratio between the sample and standard density. Results: The trend from the first to equilibrium TVL was an increase in thickness, compared with MC modeling, which predicted a decrease. Measured TVLs for 6 MV were reduced by as much as 8.9 cm for TVL{sub 1} and 3.4 cm for TVL{sub E} compared to values scaled from NCRP 151. There was 1–3 mm difference in TVL between measurements done at 4x4 versus 30x30 cm{sup 2}. TVL{sub 1} for 6FFF was 1.1 cm smaller than TVL{sub 1} for 6MV, but TVL{sub E} was consistent to within 4 mm. TVL{sub 1} and TVL{sub E} for 10FFF were reduced by 8.8 and 3.7 cm from scaled NCRP values, respectively. Conclusions: We have measured the TVL thicknesses for various concretes. Simple density scaling of the values in NCRP 151 is a conservatively safe approximation, but actual TVLs may be reduced enough to eliminate some of the expense of installation. Daniel Harrell and Jim Noller are employees of Shielding Construction Solutions, Inc, the shielding construction company that built

  9. The parameters and measurements of the destabilizing actions of rotating machines, and the assumptions of the 1950's

    NASA Technical Reports Server (NTRS)

    Bently, D. E.

    1980-01-01

    The measurability of destabilizing actions is demonstrated for a rotor built to produce a forward circular, self excited malfunction (gas whip). It is argued that the continued use of past modeling technqiues is unfortunate in that it has led to the use of inappropriate words to express what is happening and a lack of full understanding of the category of forward circular whip instability mechanisms.

  10. In-plane ultrasonic velocity measurement of longitudinal and shear waves in the machine direction with transducers in rotating wheels

    DOEpatents

    Hall, Maclin S.; Jackson, Theodore G.; Knerr, Christopher

    1998-02-17

    An improved system for measuring the velocity of ultrasonic signals within the plane of moving web-like materials, such as paper, paperboard and the like. In addition to velocity measurements of ultrasonic signals in the plane of the web in the MD and CD, one embodiment of the system in accordance with the present invention is also adapted to provide on-line indication of the polar specific stiffness of the moving web. In another embodiment of the invention, the velocity of ultrasonic signals in the plane of the web are measured by way of a plurality of ultrasonic transducers carried by synchronously driven wheels or cylinders, thus eliminating undue transducer wear due to any speed differences between the transducers and the web. In order to provide relatively constant contact force between the transducers and the webs, the transducers are mounted in a sensor housings which include a spring for biasing the transducer radially outwardly. The sensor housings are adapted to be easily and conveniently mounted to the carrier to provide a relatively constant contact force between the transducers and the moving web.

  11. In-plane ultrasonic velocity measurement of longitudinal and shear waves in the machine direction with transducers in rotating wheels

    DOEpatents

    Hall, M.S.; Jackson, T.G.; Knerr, C.

    1998-02-17

    An improved system for measuring the velocity of ultrasonic signals within the plane of moving web-like materials, such as paper, paperboard and the like. In addition to velocity measurements of ultrasonic signals in the plane of the web in the MD and CD, one embodiment of the system in accordance with the present invention is also adapted to provide on-line indication of the polar specific stiffness of the moving web. In another embodiment of the invention, the velocity of ultrasonic signals in the plane of the web are measured by way of a plurality of ultrasonic transducers carried by synchronously driven wheels or cylinders, thus eliminating undue transducer wear due to any speed differences between the transducers and the web. In order to provide relatively constant contact force between the transducers and the webs, the transducers are mounted in a sensor housings which include a spring for biasing the transducer radially outwardly. The sensor housings are adapted to be easily and conveniently mounted to the carrier to provide a relatively constant contact force between the transducers and the moving web. 37 figs.

  12. Plate mode velocities in graphite/epoxy plates

    NASA Technical Reports Server (NTRS)

    Prosser, W. H.; Gorman, M. R.

    1994-01-01

    Measurements of the velocities of the extensional and flexural plate modes were made along three directions of propagation in four graphite/epoxy composite plates. The acoustic signals were generated by simulated acoustic emission events (pencil lead breaks or Hsu-Neilson sources) and detected by by broadband ultrasonic transducers. The first arrival of the extensional plate mode, which is nondispersive at low frequencies, was measured at a number of different distances from the source along the propagation direction of interest. The velocity was determined by plotting the distance versus arrival time and computing its slope. Because of the large dispersion of the flexural mode, a Fourier phase velocity technique was used to characterize this mode. The velocity was measured up to a frequency of 160 kHz. Theoretical predictions of the velocities of these modes were also made and compared with experimental observations. Classical plate theory yields good agreement with the measured extensional velocities. For predictions of the dispersion of the flexural mode, Mindlin plates theory, which includes the effects of shear deformation and rotatory inertia was shown to give better agreement with the experimental measurements.

  13. Measurements of secondary scintillation in low-pressure CF4 with a SiPM, from a parallel-plate avalanche geometry

    NASA Astrophysics Data System (ADS)

    Cortesi, M.; Yurkon, J.; Stolz, A.

    2016-04-01

    In this work we report and discuss the characterization of the secondary scintillation light emitted by low-pressure tetrafluoromethane (CF4) during avalanche gas processes. The experimental setup consists of a Parallel Plate Avalanche Counter (PPAC) irradiated by 5.5 MeV alpha particles from a collimated 241-Am source. The PPAC is operated in CF4 at pressures ranging from 5 to 50 torr. The electroluminescence light is readout by a VUV-sensitive Multi-Pixel Photon Counter (MPPC, Hamamatsu), placed along the PPAC axial direction. The secondary scintillation yield at different operational pressures was computed from the correlation between avalanche charge and electroluminesce light, recorded on an event-by-event basis; it was found to be in the range of 0.01-0.15 photons/electron depending on the reduced field applied between the PPAC electrodes. The role of the quencher impurities is also briefly discussed. In addition, the coincidence resolving times (CRT) for 5.5 MeV α -particles crossing the PPAC has been measured; time resolutions of 600 picosecond were achieved at different pressures.

  14. Stress and strain relaxation in magnesium AZ31 rolled plate: In-situ neutron measurement and elastic viscoplastic polycrystal modeling

    SciTech Connect

    Wang, Huamiao; Clausen, Bjorn; Capolungo, Laurent; Beyerlein, Irene Jane; Wang, Jian; Tome, Carlos N.

    2015-07-16

    Continuous mechanical tests with strain holds (stress relaxation) and with stress holds (strain relaxation) are performed simultaneously with in-situ neutron measurements to analyze the mechanisms of stress and strain relaxation in Mg AZ31 rolled plate. A dislocation activity based constitutive model, accounting for internal stress statistical distributions, is proposed and implemented into an elastic viscoplastic self-consistent (EVPSC) framework to simultaneously describe both stress and strain relaxation. The model captures the experimental data in terms of macroscopic stress strain curves, evolution of stress and strain during holding, as well as evolution of the internal elastic strains. Model results indicate that the magnitude of the stress relaxed during strain holding is dependent on both, the magnitude of the flow stress and the spread of the resolved shear stress distribution. The magnitude of strain accumulated during stress holding is, on the other hand, dependent on the magnitude of the hardening rate and on the spread of the resolved shear stress distribution. Furthermore, the internal elastic strains are directly correlated with the stress state, and hence the stress relaxation during strain holds has a greater influence on the lattice strains than strain relaxation during stress holds.

  15. Parallel machines: Parallel machine languages

    SciTech Connect

    Iannucci, R.A. )

    1990-01-01

    This book presents a framework for understanding the tradeoffs between the conventional view and the dataflow view with the objective of discovering the critical hardware structures which must be present in any scalable, general-purpose parallel computer to effectively tolerate latency and synchronization costs. The author presents an approach to scalable general purpose parallel computation. Linguistic Concerns, Compiling Issues, Intermediate Language Issues, and hardware/technological constraints are presented as a combined approach to architectural Develoement. This book presents the notion of a parallel machine language.

  16. Integrating Oil Debris and Vibration Measurements for Intelligent Machine Health Monitoring. Degree awarded by Toledo Univ., May 2002

    NASA Technical Reports Server (NTRS)

    Dempsey, Paula J.

    2003-01-01

    A diagnostic tool for detecting damage to gears was developed. Two different measurement technologies, oil debris analysis and vibration were integrated into a health monitoring system for detecting surface fatigue pitting damage on gears. This integrated system showed improved detection and decision-making capabilities as compared to using individual measurement technologies. This diagnostic tool was developed and evaluated experimentally by collecting vibration and oil debris data from fatigue tests performed in the NASA Glenn Spur Gear Fatigue Rig. An oil debris sensor and the two vibration algorithms were adapted as the diagnostic tools. An inductance type oil debris sensor was selected for the oil analysis measurement technology. Gear damage data for this type of sensor was limited to data collected in the NASA Glenn test rigs. For this reason, this analysis included development of a parameter for detecting gear pitting damage using this type of sensor. The vibration data was used to calculate two previously available gear vibration diagnostic algorithms. The two vibration algorithms were selected based on their maturity and published success in detecting damage to gears. Oil debris and vibration features were then developed using fuzzy logic analysis techniques, then input into a multi sensor data fusion process. Results show combining the vibration and oil debris measurement technologies improves the detection of pitting damage on spur gears. As a result of this research, this new diagnostic tool has significantly improved detection of gear damage in the NASA Glenn Spur Gear Fatigue Rigs. This research also resulted in several other findings that will improve the development of future health monitoring systems. Oil debris analysis was found to be more reliable than vibration analysis for detecting pitting fatigue failure of gears and is capable of indicating damage progression. Also, some vibration algorithms are as sensitive to operational effects as they

  17. Accurate measurements of vadose zone fluxes using automated equilibrium tension plate lysimeters: A synopsis of results from the Spydia research facility, New Zealand.

    NASA Astrophysics Data System (ADS)

    Wöhling, Thomas; Barkle, Greg; Stenger, Roland; Moorhead, Brian; Wall, Aaron; Clague, Juliet

    2014-05-01

    Automated equilibrium tension plate lysimeters (AETLs) are arguably the most accurate method to measure unsaturated water and contaminant fluxes below the root zone at the scale of up to 1 m². The AETL technique utilizes a porous sintered stainless-steel plate to provide a comparatively large sampling area with a continuously controlled vacuum that is in "equilibrium" with the surrounding vadose zone matric pressure to ensure measured fluxes represent those under undisturbed conditions. This novel lysimeter technique was used at an intensive research site for investigations of contaminant pathways from the land surface to the groundwater on a sheep and beef farm under pastoral land use in the Tutaeuaua subcatchment, New Zealand. The Spydia research facility was constructed in 2005 and was fully operational between 2006 and 2011. Extending from a central access caisson, 15 separately controlled AETLs with 0.2 m² surface area were installed at five depths between 0.4 m and 5.1 m into the undisturbed volcanic vadose zone materials. The unique setup of the facility ensured minimum interference of the experimental equipment and external factors with the measurements. Over the period of more than five years, a comprehensive data set was collected at each of the 15 AETL locations which comprises of time series of soil water flux, pressure head, volumetric water contents, and soil temperature. The soil water was regularly analysed for EC, pH, dissolved carbon, various nitrogen compounds (including nitrate, ammonia, and organic N), phosphorus, bromide, chloride, sulphate, silica, and a range of other major ions, as well as for various metals. Climate data was measured directly at the site (rainfall) and a climate station at 500m distance. The shallow groundwater was sampled at three different depths directly from the Spydia caisson and at various observation wells surrounding the facility. Two tracer experiments were conducted at the site in 2009 and 2010. In the 2009

  18. Equilibrium drug solubility measurements in 96-well plates reveal similar drug solubilities in phosphate buffer pH 6.8 and human intestinal fluid.

    PubMed

    Heikkilä, Tiina; Karjalainen, Milja; Ojala, Krista; Partola, Kirsi; Lammert, Frank; Augustijns, Patrick; Urtti, Arto; Yliperttula, Marjo; Peltonen, Leena; Hirvonen, Jouni

    2011-02-28

    This study was conducted to develop a high throughput screening (HTS) method for the assessment of equilibrium solubility of drugs. Solid-state compounds were precipitated from methanol in 96-well plates, in order to eliminate the effect of co-solvent. Solubility of twenty model drugs was analyzed in water and aqueous solutions (pH 1.2 and 6.8) in 96-well plates and in shake-flasks (UV detection). The results obtained with the 96-well plate method correlated well (R(2)=0.93) between the shake-flask and 96-well plates over the wide concentration scale of 0.002-169.2mg/ml. Thereafter, the solubility tests in 96-well plates were performed using fasted state human intestinal fluid (HIF) from duodenum of healthy volunteers. The values of solubility were similar in phosphate buffer solution (pH 6.8) and HIF over the solubility range of 10(2)-10(5)μg/ml. The new 96-well plate method is useful for the screening of equilibrium drug solubility during the drug discovery process and it also allows the use of human intestinal fluid in solubility screening.

  19. Gated Microchannel Plate Photomultiplier For Longitudinal BeamDiagnostics

    SciTech Connect

    Byrd, John M.; De Santis, Stefano; Thurman-Keup, Randy

    2006-05-03

    A gated microchannel plate photomultiplier can be used as aneffective tool for measuring the longitudinal distribution of particlesaround most electron and high-energy proton rings. The broad availablewavelength range,low noise, and high sensitivity allow using such adevice for measuring the emitted synchrotron radiation and to extract thebeam intensity. The fast gate rise time can be used to reject strongsignals coming from filled RF buckets and avoid saturation of thephotocathode so that it is possible to monitor, with a high degree ofresolution, gaps in the machine fill and growth of parasitic bunches. Therugged characteristics of the device and its simplicity of use make itideal for all those applications where more complex and expensiveinstrumentation is not absolutely necessary. We present the experimentalresults obtained at the Advanced Light Source and on the Tevatron usingan Hamamatsu R5916U-50 series model.

  20. Sputtering and ion plating

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The proceedings of a conference on sputtering and ion plating are presented. Subjects discussed are: (1) concepts and applications of ion plating, (2) sputtering for deposition of solid film lubricants, (3) commercial ion plating equipment, (4) industrial potential for ion plating and sputtering, and (5) fundamentals of RF and DC sputtering.

  1. Fringe Capacitance of a Parallel-Plate Capacitor.

    ERIC Educational Resources Information Center

    Hale, D. P.

    1978-01-01

    Describes an experiment designed to measure the forces between charged parallel plates, and determines the relationship among the effective electrode area, the measured capacitance values, and the electrode spacing of a parallel plate capacitor. (GA)

  2. Biosleeve Human-Machine Interface

    NASA Technical Reports Server (NTRS)

    Assad, Christopher (Inventor)

    2016-01-01

    Systems and methods for sensing human muscle action and gestures in order to control machines or robotic devices are disclosed. One exemplary system employs a tight fitting sleeve worn on a user arm and including a plurality of electromyography (EMG) sensors and at least one inertial measurement unit (IMU). Power, signal processing, and communications electronics may be built into the sleeve and control data may be transmitted wirelessly to the controlled machine or robotic device.

  3. Machine Gun Liner Bond Strength

    DTIC Science & Technology

    2007-08-01

    investigation does not constitute a complete analysis of liner failures in the M2 machine gun. The fact that two different liner-failure modes were...An order-of-magnitude estimate can be made of the bond strength in this case using a standard elastic analysis and some reasonable assumptions... analysis of the forces on the machine gun bullet, it was found that the measured bond strength was adequate to resist the reaction forces produced when

  4. Machine Learning for Medical Imaging.

    PubMed

    Erickson, Bradley J; Korfiatis, Panagiotis; Akkus, Zeynettin; Kline, Timothy L

    2017-01-01

    Machine learning is a technique for recognizing patterns that can be applied to medical images. Although it is a powerful tool that can help in rendering medical diagnoses, it can be misapplied. Machine learning typically begins with the machine learning algorithm system computing the image features that are believed to be of importance in making the prediction or diagnosis of interest. The machine learning algorithm system then identifies the best combination of these image features for classifying the image or computing some metric for the given image region. There are several methods that can be used, each with different strengths and weaknesses. There are open-source versions of most of these machine learning methods that make them easy to try and apply to images. Several metrics for measuring the performance of an algorithm exist; however, one must be aware of the possible associated pitfalls that can result in misleading metrics. More recently, deep learning has started to be used; this method has the benefit that it does not require image feature identification and calculation as a first step; rather, features are identified as part of the learning process. Machine learning has been used in medical imaging and will have a greater influence in the future. Those working in medical imaging must be aware of how machine learning works. (©)RSNA, 2017.

  5. Machine vision for digital microfluidics.

    PubMed

    Shin, Yong-Jun; Lee, Jeong-Bong

    2010-01-01

    Machine vision is widely used in an industrial environment today. It can perform various tasks, such as inspecting and controlling production processes, that may require humanlike intelligence. The importance of imaging technology for biological research or medical diagnosis is greater than ever. For example, fluorescent reporter imaging enables scientists to study the dynamics of gene networks with high spatial and temporal resolution. Such high-throughput imaging is increasingly demanding the use of machine vision for real-time analysis and control. Digital microfluidics is a relatively new technology with expectations of becoming a true lab-on-a-chip platform. Utilizing digital microfluidics, only small amounts of biological samples are required and the experimental procedures can be automatically controlled. There is a strong need for the development of a digital microfluidics system integrated with machine vision for innovative biological research today. In this paper, we show how machine vision can be applied to digital microfluidics by demonstrating two applications: machine vision-based measurement of the kinetics of biomolecular interactions and machine vision-based droplet motion control. It is expected that digital microfluidics-based machine vision system will add intelligence and automation to high-throughput biological imaging in the future.

  6. Study of on-machine error identification and compensation methods for micro machine tools

    NASA Astrophysics Data System (ADS)

    Wang, Shih-Ming; Yu, Han-Jen; Lee, Chun-Yi; Chiu, Hung-Sheng

    2016-08-01

    Micro machining plays an important role in the manufacturing of miniature products which are made of various materials with complex 3D shapes and tight machining tolerance. To further improve the accuracy of a micro machining process without increasing the manufacturing cost of a micro machine tool, an effective machining error measurement method and a software-based compensation method are essential. To avoid introducing additional errors caused by the re-installment of the workpiece, the measurement and compensation method should be on-machine conducted. In addition, because the contour of a miniature workpiece machined with a micro machining process is very tiny, the measurement method should be non-contact. By integrating the image re-constructive method, camera pixel correction, coordinate transformation, the error identification algorithm, and trajectory auto-correction method, a vision-based error measurement and compensation method that can on-machine inspect the micro machining errors and automatically generate an error-corrected numerical control (NC) program for error compensation was developed in this study. With the use of the Canny edge detection algorithm and camera pixel calibration, the edges of the contour of a machined workpiece were identified and used to re-construct the actual contour of the work piece. The actual contour was then mapped to the theoretical contour to identify the actual cutting points and compute the machining errors. With the use of a moving matching window and calculation of the similarity between the actual and theoretical contour, the errors between the actual cutting points and theoretical cutting points were calculated and used to correct the NC program. With the use of the error-corrected NC program, the accuracy of a micro machining process can be effectively improved. To prove the feasibility and effectiveness of the proposed methods, micro-milling experiments on a micro machine tool were conducted, and the results

  7. Evaluating the diagnostic utility of applying a machine learning algorithm to diffusion tensor MRI measures in individuals with major depressive disorder.

    PubMed

    Schnyer, David M; Clasen, Peter C; Gonzalez, Christopher; Beevers, Christopher G

    2017-03-23

    Using MRI to diagnose mental disorders has been a long-term goal. Despite this, the vast majority of prior neuroimaging work has been descriptive rather than predictive. The current study applies support vector machine (SVM) learning to MRI measures of brain white matter to classify adults with Major Depressive Disorder (MDD) and healthy controls. In a precisely matched group of individuals with MDD (n =25) and healthy controls (n =25), SVM learning accurately (74%) classified patients and controls across a brain map of white matter fractional anisotropy values (FA). The study revealed three main findings: 1) SVM applied to DTI derived FA maps can accurately classify MDD vs. healthy controls; 2) prediction is strongest when only right hemisphere white matter is examined; and 3) removing FA values from a region identified by univariate contrast as significantly different between MDD and healthy controls does not change the SVM accuracy. These results indicate that SVM learning applied to neuroimaging data can classify the presence versus absence of MDD and that predictive information is distributed across brain networks rather than being highly localized. Finally, MDD group differences revealed through typical univariate contrasts do not necessarily reveal patterns that provide accurate predictive information.

  8. Characterization and analysis of surface notches on Ti-alloy plates fabricated by additive manufacturing techniques

    NASA Astrophysics Data System (ADS)

    Chan, Kwai S.

    2015-12-01

    Rectangular plates of Ti-6Al-4V with extra low interstitial (ELI) were fabricated by layer-by-layer deposition techniques that included electron beam melting (EBM) and laser beam melting (LBM). The surface conditions of these plates were characterized using x-ray micro-computed tomography. The depth and radius of surface notch-like features on the LBM and EBM plates were measured from sectional images of individual virtual slices of the rectangular plates. The stress concentration factors of individual surface notches were computed and analyzed statistically to determine the appropriate distributions for the notch depth, notch radius, and stress concentration factor. These results were correlated with the fatigue life of the Ti-6Al-4V ELI alloys from an earlier investigation. A surface notch analysis was performed to assess the debit in the fatigue strength due to the surface notches. The assessment revealed that the fatigue lives of the additively manufactured plates with rough surface topographies and notch-like features are dominated by the fatigue crack growth of large cracks for both the LBM and EBM materials. The fatigue strength reduction due to the surface notches can be as large as 60%-75%. It is concluded that for better fatigue performance, the surface notches on EBM and LBM materials need to be removed by machining and the surface roughness be improved to a surface finish of about 1 μm.

  9. Machine musicianship

    NASA Astrophysics Data System (ADS)

    Rowe, Robert

    2002-05-01

    The training of musicians begins by teaching basic musical concepts, a collection of knowledge commonly known as musicianship. Computer programs designed to implement musical skills (e.g., to make sense of what they hear, perform music expressively, or compose convincing pieces) can similarly benefit from access to a fundamental level of musicianship. Recent research in music cognition, artificial intelligence, and music theory has produced a repertoire of techniques that can make the behavior of computer programs more musical. Many of these were presented in a recently published book/CD-ROM entitled Machine Musicianship. For use in interactive music systems, we are interested in those which are fast enough to run in real time and that need only make reference to the material as it appears in sequence. This talk will review several applications that are able to identify the tonal center of musical material during performance. Beyond this specific task, the design of real-time algorithmic listening through the concurrent operation of several connected analyzers is examined. The presentation includes discussion of a library of C++ objects that can be combined to perform interactive listening and a demonstration of their capability.

  10. Validating the BTrackS Balance Plate as a low cost alternative for the measurement of sway-induced center of pressure.

    PubMed

    O'Connor, Shawn M; Baweja, Harsimran S; Goble, Daniel J

    2016-12-08

    The BTrackS Balance Plate (BBP) is a low-cost force plate that provides objective balance assessment and true portability for the user. Given that this technology is relatively new, the purpose of the present study was to provide the first center of pressure (COP) validation of the BBP. Two BBP devices (one new and one used) were compared with a laboratory-grade force plate (LFP) during simultaneous collection of COP that was induced by an inverted pendulum device with human-like sway characteristics. The results of this study showed almost perfect agreement between the BBP devices and the LFP (ICC>0.999), as well as a high degree of BBP accuracy (<1% error magnitude) and precision (<0.2mm regression residuals). These results suggest the BBP can serve as an effective, low-cost solution for objective balance testing in the laboratory or clinic.

  11. Rapid Fabrication of Flat Plate Cavity Phosphor Thermography Test Models for Shuttle Return-to-Flight Aero-Heating

    NASA Technical Reports Server (NTRS)

    Buck, Gregory M.; Powers, Michael A.; Nevins, Stephen C.; Griffith, Mark S.; Wainwright, Gary A.

    2006-01-01

    Methods, materials and equipment are documented for fabricating flat plate test models at NASA Langley Research Center for Shuttle return-to-flight aeroheating experiments simulating open and closed cavity interactions in Langley s hypersonic 20-Inch Mach 6 air wind tunnel. Approximately 96 silica ceramic flat plate cavity phosphor thermography test models have been fabricated using these methods. On one model, an additional slot is machined through the back of the plate and into the cavity and vented into an evacuated plenum chamber to simulate a further opening in the cavity. After sintering ceramic to 2150 F, and mounting support hardware, a ceramic-based two-color thermographic phosphor coating is applied for global temperature and heat transfer measurements, with fiducial markings for image registration.

  12. Fixture For Crush Testing Of Composite Plates

    NASA Technical Reports Server (NTRS)

    Jackson, Karen E.; Lavoie, J. Andre; Morton, John

    1995-01-01

    Test fixture holds composite-material (matrix/fiber) plate specimens for crush testing in universal compression-testing machine to determine energy absorption characteristics of composite material system and laminate. Accommodates specimens of two different sizes; 6 by 4 by 0.16 in. and 3 by 2 by 0.08 in., designated as full scale and half scale, respectively. Contributes to development of more crashworthy composite-material structural components of aircraft.

  13. Flotation machine

    SciTech Connect

    Zlobin, M.N.; Permyakov, G.P.; Nemarov, A.A.; Metsik, V.M.; Medetsky, J.V.; Taraban, N.T.

    1993-08-10

    A flotation machine is described for beneficiating minerals comprising: a vertical cylindrical chamber for circulating a flotation pulp; a downwardly tapered bottom connected to said vertical cylindrical chamber; feed pipe means for feeding the flotation pulp carrying mineral particles of fine fraction, particles of the useful ingredient of the fine fraction being capable of floating up from the volume of said aerated pulp; discharge pipe means connected to the tapered bottom near its lowest point for discharging gangue; an annular trough for collecting froth concentrate at the top of said chamber; a group of frustoconical shells each having bases of different diameters and a tapered surface secured axially in said chamber and spaced equidistantly from one another height wise of said chamber; aerator means for aerating the flotation pulp secured to the walls of said chamber and communicating therewith to provide aerated water into said chamber; means for feeding mineral particles of coarse fraction, particles of the useful ingredient of the coarse fraction being capable of floating in the froth layer of the flotation pulp, in the form of a hydrocyclone having a cylindrical casing positioned axially over said chamber and a downwardly tapering outlet directed downwardly to feed the coarse particles to said chamber; feed pipe means for feeding the flotation pulp carrying mineral particles of coarse fraction positioned tangentially at said cylindrical casing of the hydrocyclone; and evacuation means for evacuating the liquid phase of the flotation pulp positioned tangentially at said casing of the hydrocyclone over said feed pipe means and connected to said feed pipe means for feeding the flotation pulp carrying mineral particles of the fine fraction.

  14. Investigation of the Timesaver process for de-burring and cleaning the plate for the Atlas Tilecalorimeter

    SciTech Connect

    Guarino, V.; Kocenko, L.; Wood, K.

    1997-11-25

    The Timesaver belt grinding machine has been selected by the Atlas collaboration for deburring the master and spacer plates after die stamping and laser cutting, respectively. However, the question has been raised as to whether or not the plates are sufficiently clean after going through the Timesaver machine to immediately be glued into a submodule assembly. This would greatly enhance the production of submodules because the task of cleaning individual master and spacer plates is labor intensive and time consuming as well as raises environmental issues with the detergent that is used. In order to investigate the possibility of using the Timesaver process to clean the plates as well as debur them, several plates were run through the machine and their cleanliness inspected before and after. In addition, several glue samples were subjected to the same process, glued, and then pulled apart in an attempt to gauge the cleanliness of the plates. From this series of tests it can be concluded that the wet Timesaver machine can adequately prepare the surface of the master and spacer plates as well as clean the plates for gluing. The machine was able to adequately remove all of the oil and grime from the test plates. Also, from the single test on the dry machine it appears that significant cleaning will be required to adequately clean the plates before gluing in order to remove the remaining grit.

  15. Machinability of Green Powder Metallurgy Components: Part II. Sintered Properties of Components Machined in Green State

    NASA Astrophysics Data System (ADS)

    Robert-Perron, Etienne; Blais, Carl; Pelletier, Sylvain; Thomas, Yannig

    2007-06-01

    The green machining process is virtually a must if the powder metallurgy (PM) industries are to solve the lower machining performances associated with PM components. This process is known for lowering the rate of tool wear. Recent improvements in binder/lubricant technologies have led to high-green-strength systems that enable green machining. Combined with the optimized cutting parameters determined in Part I of the study, the green machining of PM components seems to be a viable process for fabricating high performance parts on large scale and complete other shaping processes. This second part of our study presents a comparison between the machining behaviors and the sintered properties of components machined prior to or after sintering. The results show that the radial crush strength measured on rings machined in their green state is equal to that of parts machined after sintering.

  16. Architectures for intelligent machines

    NASA Technical Reports Server (NTRS)

    Saridis, George N.

    1991-01-01

    The theory of intelligent machines has been recently reformulated to incorporate new architectures that are using neural and Petri nets. The analytic functions of an intelligent machine are implemented by intelligent controls, using entropy as a measure. The resulting hierarchical control structure is based on the principle of increasing precision with decreasing intelligence. Each of the three levels of the intelligent control is using different architectures, in order to satisfy the requirements of the principle: the organization level is moduled after a Boltzmann machine for abstract reasoning, task planning and decision making; the coordination level is composed of a number of Petri net transducers supervised, for command exchange, by a dispatcher, which also serves as an interface to the organization level; the execution level, include the sensory, planning for navigation and control hardware which interacts one-to-one with the appropriate coordinators, while a VME bus provides a channel for database exchange among the several devices. This system is currently implemented on a robotic transporter, designed for space construction at the CIRSSE laboratories at the Rensselaer Polytechnic Institute. The progress of its development is reported.

  17. Thermal conductance of gold plated metallic contacts at liquid helium temperatures

    NASA Technical Reports Server (NTRS)

    Kittel, Peter; Spivak, Alan L.; Salerno, Louis J.

    1992-01-01

    The thermal conductance of gold plated OFHC copper, 6061-T6 aluminum, free-machining brass, and 304 stainless steel contacts has been measured over the temperature range of 1.6 to 4.2 K, with applied forces from 22 N to 670 N. The contact surfaces were prepared with a 0.8 micron lapped finish prior to gold coating. It was found that for all materials, except stainless steel, the thermal conductance was significantly improved as the result of gold coating the contact surfaces.

  18. Adapter plate assembly for adjustable mounting of objects

    DOEpatents

    Blackburn, Robert S.

    1987-01-01

    An adapter plate and two locking discs are together affixed to an optic table with machine screws or bolts threaded into a fixed array of internally threaded holes provided in the table surface. The adapter plate preferably has two, and preferably parallel, elongated locating slots each freely receiving a portion of one of the locking discs for secure affixation of the adapter plate to the optic table. A plurality of threaded apertures provided in the adapter plate are available to attach optical mounts or other devices onto the adapter plate in an orientation not limited by the disposition of the array of threaded holes in the table surface. An axially aligned but radially offset hole through each locking disc receives a screw that tightens onto the table, such that prior to tightening of the screw the locking disc may rotate and translate within each locating slot of the adapter plate for maximum flexibility of the orientation thereof.

  19. Adapter plate assembly for adjustable mounting of objects

    DOEpatents

    Blackburn, R.S.

    1986-05-02

    An adapter plate and two locking discs are together affixed to an optic table with machine screws or bolts threaded into a fixed array of internally threaded holes provided in the table surface. The adapter plate preferably has two, and preferably parallel, elongated locating slots each freely receiving a portion of one of the locking discs for secure affixation of the adapter plate to the optic table. A plurality of threaded apertures provided in the adapter plate are available to attach optical mounts or other devices onto the adapter plate in an orientation not limited by the disposition of the array of threaded holes in the table surface. An axially aligned but radially offset hole through each locking disc receives a screw that tightens onto the table, such that prior to tightening of the screw the locking disc may rotate and translate within each locating slot of the adapter plate for maximum flexibility of the orientation thereof.

  20. Ornament Problem Suppression in Indonesian License Plate Recognition Systems

    NASA Astrophysics Data System (ADS)

    Mahatmaputra Tedjojuwono, Samuel

    2017-03-01

    Based on the original work of fast performance algorithm in detecting Indonesian license plate, the proposed work will solve the error found in the license plate localization process caused by plate like pattern within the image, which was called the ornament problem. Although not in all cases, this problem could exist when a car has banner, regular pattern, car’s front grill, that could miss understood by the system as license plate letters. The proposed work will implement filtering systems instead of machine learning approach. The filtering methods will follows three steps: detection filter based on the number of elements in the vector, based on the letter proportion of a license plate number, and based on the distance between detected letters. This approach will maintain the fast properties of the original algorithm and will increase the accuracy of localizing the license plate within the given image.