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Sample records for surface profile measurement

  1. The prediction of BRDFs from surface profile measurements

    International Nuclear Information System (INIS)

    Church, E.L.; Takacs, P.Z.; Leonard, T.A.

    1989-01-01

    This paper discusses methods of predicting the BRDF of smooth surfaces from profile measurements of their surface finish. The conversion of optical profile data to the BRDF at the same wavelength is essentially independent of scattering models, while the conversion of mechanical measurements, and wavelength scaling in general, are model dependent. Procedures are illustrated for several surfaces, including two from the recent HeNe BRDF round robin, and results are compared with measured data. Reasonable agreement is found except for surfaces which involve significant scattering from isolated surface defects which are poorly sampled in the profile data

  2. Indirect measurement of near-surface velocity and pressure fields based on measurement of moving free surface profiles

    International Nuclear Information System (INIS)

    Sibamoto, Yasuteru; Nakamura, Hideo

    2005-01-01

    A non-intrusive technique for measurement of the velocity and pressure fields adjacent to a moving fluid surface is developed. The technique is based on the measurement of fluid surface profile. The velocity and pressure fields are derived with use of the boundary element method (BEM) by seeking for an incompressible flow field that satisfies the kinematic boundary condition imposed by the time-dependent fluid surface profile. The proposed technique is tested by deriving the velocity and pressure fields inversely from the fluid surface profiles obtained by a forward BEM calculation of fluid surface response to externally-imposed pressure. The inverse calculation results show good agreement with the imposed pressure distribution in the forward calculation. (author)

  3. Comparison of two methods of surface profile extraction from multiple ultrasonic range measurements

    NARCIS (Netherlands)

    Barshan, B; Baskent, D

    Two novel methods for surface profile extraction based on multiple ultrasonic range measurements are described and compared. One of the methods employs morphological processing techniques, whereas the other employs a spatial voting scheme followed by simple thresholding. Morphological processing

  4. The deconvolution of sputter-etching surface concentration measurements to determine impurity depth profiles

    International Nuclear Information System (INIS)

    Carter, G.; Katardjiev, I.V.; Nobes, M.J.

    1989-01-01

    The quasi-linear partial differential continuity equations that describe the evolution of the depth profiles and surface concentrations of marker atoms in kinematically equivalent systems undergoing sputtering, ion collection and atomic mixing are solved using the method of characteristics. It is shown how atomic mixing probabilities can be deduced from measurements of ion collection depth profiles with increasing ion fluence, and how this information can be used to predict surface concentration evolution. Even with this information, however, it is shown that it is not possible to deconvolute directly the surface concentration measurements to provide initial depth profiles, except when only ion collection and sputtering from the surface layer alone occur. It is demonstrated further that optimal recovery of initial concentration depth profiles could be ensured if the concentration-measuring analytical probe preferentially sampled depths near and at the maximum depth of bombardment-induced perturbations. (author)

  5. In Situ Aerosol Profile Measurements and Comparisons with SAGE 3 Aerosol Extinction and Surface Area Profiles at 68 deg North

    Science.gov (United States)

    2005-01-01

    Under funding from this proposal three in situ profile measurements of stratospheric sulfate aerosol and ozone were completed from balloon-borne platforms. The measured quantities are aerosol size resolved number concentration and ozone. The one derived product is aerosol size distribution, from which aerosol moments, such as surface area, volume, and extinction can be calculated for comparison with SAGE III measurements and SAGE III derived products, such as surface area. The analysis of these profiles and comparison with SAGE III extinction measurements and SAGE III derived surface areas are provided in Yongxiao (2005), which comprised the research thesis component of Mr. Jian Yongxiao's M.S. degree in Atmospheric Science at the University of Wyoming. In addition analysis continues on using principal component analysis (PCA) to derive aerosol surface area from the 9 wavelength extinction measurements available from SAGE III. Ths paper will present PCA components to calculate surface area from SAGE III measurements and compare these derived surface areas with those available directly from in situ size distribution measurements, as well as surface areas which would be derived from PCA and Thomason's algorithm applied to the four wavelength SAGE II extinction measurements.

  6. Moving gantry method for electron beam dose profile measurement at extended source-to-surface distances.

    Science.gov (United States)

    Fekete, Gábor; Fodor, Emese; Pesznyák, Csilla

    2015-03-08

    A novel method has been put forward for very large electron beam profile measurement. With this method, absorbed dose profiles can be measured at any depth in a solid phantom for total skin electron therapy. Electron beam dose profiles were collected with two different methods. Profile measurements were performed at 0.2 and 1.2 cm depths with a parallel plate and a thimble chamber, respectively. 108cm × 108 cm and 45 cm × 45 cm projected size electron beams were scanned by vertically moving phantom and detector at 300 cm source-to-surface distance with 90° and 270° gantry angles. The profiles collected this way were used as reference. Afterwards, the phantom was fixed on the central axis and the gantry was rotated with certain angular steps. After applying correction for the different source-to-detector distances and incidence of angle, the profiles measured in the two different setups were compared. Correction formalism has been developed. The agreement between the cross profiles taken at the depth of maximum dose with the 'classical' scanning and with the new moving gantry method was better than 0.5 % in the measuring range from zero to 71.9 cm. Inverse square and attenuation corrections had to be applied. The profiles measured with the parallel plate chamber agree better than 1%, except for the penumbra region, where the maximum difference is 1.5%. With the moving gantry method, very large electron field profiles can be measured at any depth in a solid phantom with high accuracy and reproducibility and with much less time per step. No special instrumentation is needed. The method can be used for commissioning of very large electron beams for computer-assisted treatment planning, for designing beam modifiers to improve dose uniformity, and for verification of computed dose profiles.

  7. Angular calibration of surface slope measuring profilers with a bendable mirror

    Science.gov (United States)

    Artemiev, Nikolay A.; Smith, Brian V.; Domning, Edward E.; Chow, Ken P.; Lacey, Ian; Yashchuk, Valeriy V.

    2014-09-01

    Performance of state-of-the-art surface slope measuring profilers, such as the Advanced Light Source's (ALS) long trace profiler (LTP-II) and developmental LTP (DLTP) is limited by the instrument's systematic error. The systematic error is specific for a particular measurement arrangement and, in general, depends on both the measured surface slope value and the position along a surface under test. Here we present an original method to characterize or measure the instrument's systematic error using a bendable X-ray mirror as a test surface. The idea of the method consists of extracting the systematic error from multiple measurements performed at different mirror bendings. An optimal measurement strategy for the optic, under different settings of the benders, and the method of accurate fitting of the measured slope variations with characteristic functions are discussed. We describe the procedure of separation of the systematic error of an actual profiler from surface slope variation inherent to the optic. The obtained systematic error, expressed as a function of the angle of measurement, is useful as a calibration of the instrument arranged to measure an optic with a close curvature and length. We show that accounting for the systematic error enables the optimal setting of bendable optics to the desired ideal shape with accuracy limited only by the experimental noise. Application of the method in the everyday metrology practice increases the accuracy of the measurements and allows measurements of highly curved optics with accuracy similar to those achieved with flat optics. This work was supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

  8. Determining the near-surface current profile from measurements of the wave dispersion relation

    Science.gov (United States)

    Smeltzer, Benjamin; Maxwell, Peter; Aesøy, Eirik; Ellingsen, Simen

    2017-11-01

    The current-induced Doppler shifts of waves can yield information about the background mean flow, providing an attractive method of inferring the current profile in the upper layer of the ocean. We present measurements of waves propagating on shear currents in a laboratory water channel, as well as theoretical investigations of inversion techniques for determining the vertical current structure. Spatial and temporal measurements of the free surface profile obtained using a synthetic Schlieren method are analyzed to determine the wave dispersion relation and Doppler shifts as a function of wavelength. The vertical current profile can then be inferred from the Doppler shifts using an inversion algorithm. Most existing algorithms rely on a priori assumptions of the shape of the current profile, and developing a method that uses less stringent assumptions is a focus of this study, allowing for measurement of more general current profiles. The accuracy of current inversion algorithms are evaluated by comparison to measurements of the mean flow profile from particle image velocimetry (PIV), and a discussion of the sensitivity to errors in the Doppler shifts is presented.

  9. Near-Surface Residual Stress-Profiling with High Frequency Eddy Current Conductivity Measurement

    Science.gov (United States)

    Hillmann, S.; Heuer, H.; Baron, H.-U.; Bamberg, J.; Yashan, A.; Meyendorf, N.

    2009-03-01

    The lifetime of aero engine components can be extended by applying an additional strain to the material. Typical aero engine-alloys like Nickel-Base superalloys or Titanium alloys can be surface-treated by use of shot peening to induce the compressive strain near the surface. However, in order to use the additional life for critical aero engine components, a quantitative determination of strain gradients near the surface has to be carried out periodically. We propose to measure the depth-profile of residual stresses non-destructively by use of high frequency eddy current techniques. This paper presents results obtained with an experimental set-up based on a high precision impedance analyzer. Test samples prepared from IN718 by shot peening of different intensities can be easily distinguished. By sweeping the frequency from 100 kHz up to 100 MHz a depth profile for the electrical conductivity from 50 μm to 500 μm can be obtained. The measured conductivity profile is a resultant from residual stresses, cold work, surface roughness and the texture of the material. In addition, first results for strain profiling obtained with industry applicable NDE instrument will be presented.

  10. Design of measurement system of 3D surface profile based on chromatic confocal technology

    Science.gov (United States)

    Wang, An-su; Xie, Bin; Liu, Zi-wei

    2018-01-01

    Chromatic confocal 3D profilometer has widely used in science investigation and industry fields recently for its high precision, great measuring range and numerical surface characteristic. It can provide exact and omnidirectional solution for manufacture and research by 3D non-contact surface analysis technique. The article analyzes the principle of surface measurement with chromatic confocal technology, and provides the designing indicators and requirements of the confocal system. As the key component, the dispersive objective used to achieve longitudinal focus vibration with wavelength was designed. The objective disperses the focus of wavelength between 400 700 nm to 15 mm longitudinal range. With selected spectrometer, the resolution of chromatic confocal 3D profilometer is no more than 5 μm, which can meet needs for the high precision non-contact surface profile measurement.

  11. Surface profile measurement by using the integrated Linnik WLSI and confocal microscope system

    Science.gov (United States)

    Wang, Wei-Chung; Shen, Ming-Hsing; Hwang, Chi-Hung; Yu, Yun-Ting; Wang, Tzu-Fong

    2017-06-01

    The white-light scanning interferometer (WLSI) and confocal microscope (CM) are the two major optical inspection systems for measuring three-dimensional (3D) surface profile (SP) of micro specimens. Nevertheless, in practical applications, WLSI is more suitable for measuring smooth and low-slope surfaces. On the other hand, CM is more suitable for measuring uneven-reflective and low-reflective surfaces. As for aspect of surface profiles to be measured, the characteristics of WLSI and CM are also different. WLSI is generally used in semiconductor industry while CM is more popular in printed circuit board industry. In this paper, a self-assembled multi-function optical system was integrated to perform Linnik white-light scanning interferometer (Linnik WLSI) and CM. A connecting part composed of tubes, lenses and interferometer was used to conjunct finite and infinite optical systems for Linnik WLSI and CM in the self-assembled optical system. By adopting the flexibility of tubes and lenses, switching to perform two different optical measurements can be easily achieved. Furthermore, based on the shape from focus method with energy of Laplacian filter, the CM was developed to enhance the on focal information of each pixel so that the CM can provide all-in-focus image for performing the 3D SP measurement and analysis simultaneously. As for Linnik WLSI, eleven-step phase shifting algorithm was used to analyze vertical scanning signals and determine the 3D SP.

  12. LASSI - A Scanning Differential Ac Interferometer For Surface Profile And Roughness Measurement

    Science.gov (United States)

    Makosch, Guenter

    1989-03-01

    LASSI (Laser Spot Scanning Interferometer) is a highly precise and versatile surface profilometer developed for various measurement applications in surface lapping, etching and polishing processes. The principle of measurement is based on a differential interferometer in which two parallel light beams split from a He-Ne laser are scanned across a sample surface. The phase difference of the reflected beams changes proportionally with the height variation between the two spots illuminated on the surface. In using a phase-locked method to determine the phase differences height variations of a surface can be measured with manometer precision. The range of applications of an instrument built on this principle encompasses step height, roughness, slope, and profile measurement of surface microtopographies. Special versions of this tool have also been developed for in situ monitoring of etch or deposition rates in sputter-etching and wet etching processes. In this paper, the principle of measurement will be described and some theoretical aspects of the measurement technique will be discussed. The various LASSI tools and their applications are reviewed.

  13. Adaptive Sampling based 3D Profile Measuring Method for Free-Form Surface

    Science.gov (United States)

    Duan, Xianyin; Zou, Yu; Gao, Qiang; Peng, Fangyu; Zhou, Min; Jiang, Guozhang

    2018-03-01

    In order to solve the problem of adaptability and scanning efficiency of the current surface profile detection device, a high precision and high efficiency detection approach is proposed for surface contour of free-form surface parts based on self- adaptability. The contact mechanical probe and the non-contact laser probe are synthetically integrated according to the sampling approach of adaptive front-end path detection. First, the front-end path is measured by the non-contact laser probe, and the detection path is planned by the internal algorithm of the measuring instrument. Then a reasonable measurement sampling is completed according to the planned path by the contact mechanical probe. The detection approach can effectively improve the measurement efficiency of the free-form surface contours and can simultaneously detect the surface contours of unknown free-form surfaces with different curvatures and even different rate of curvature. The detection approach proposed in this paper also has important reference value for free-form surface contour detection.

  14. Vertical profiles of aerosol optical properties over central Illinois and comparison with surface and satellite measurements

    Science.gov (United States)

    Sheridan, P. J.; Andrews, E.; Ogren, J. A.; Tackett, J. L.; Winker, D. M.

    2012-12-01

    Between June 2006 and September 2009, an instrumented light aircraft measured over 400 vertical profiles of aerosol and trace gas properties over eastern and central Illinois. The primary objectives of this program were to (1) measure the in situ aerosol properties and determine their vertical and temporal variability and (2) relate these aircraft measurements to concurrent surface and satellite measurements. The primary profile location was within 15 km of the NOAA/ESRL surface aerosol monitoring station near Bondville, Illinois. Identical instruments at the surface and on the aircraft ensured that the data from both platforms would be directly comparable and permitted a determination of how representative surface aerosol properties were of the lower column. Aircraft profiles were also conducted occasionally at two other nearby locations to increase the frequency of A-Train satellite underflights for the purpose of comparing in situ and satellite-retrieved aerosol data. Measurements of aerosol properties conducted at low relative humidity over the Bondville site compare well with the analogous surface aerosol data and do not indicate any major sampling issues or that the aerosol is radically different at the surface compared with the lowest flyby altitude of ~ 240 m above ground level. Statistical analyses of the in situ vertical profile data indicate that aerosol light scattering and absorption (related to aerosol amount) decreases substantially with increasing altitude. Parameters related to the nature of the aerosol (e.g., single-scattering albedo, Ångström exponent, etc.), however, are relatively constant throughout the mixed layer, and do not vary as much as the aerosol amount throughout the profile. While individual profiles often showed more variability, the median in situ single-scattering albedo was 0.93-0.95 for all sampled altitudes. Several parameters (e.g., submicrometer scattering fraction, hemispheric backscattering fraction, and scattering

  15. Vertical profiles of aerosol optical properties over central Illinois and comparison with surface and satellite measurements

    Directory of Open Access Journals (Sweden)

    P. J. Sheridan

    2012-12-01

    Full Text Available Between June 2006 and September 2009, an instrumented light aircraft measured over 400 vertical profiles of aerosol and trace gas properties over eastern and central Illinois. The primary objectives of this program were to (1 measure the in situ aerosol properties and determine their vertical and temporal variability and (2 relate these aircraft measurements to concurrent surface and satellite measurements. The primary profile location was within 15 km of the NOAA/ESRL surface aerosol monitoring station near Bondville, Illinois. Identical instruments at the surface and on the aircraft ensured that the data from both platforms would be directly comparable and permitted a determination of how representative surface aerosol properties were of the lower column. Aircraft profiles were also conducted occasionally at two other nearby locations to increase the frequency of A-Train satellite underflights for the purpose of comparing in situ and satellite-retrieved aerosol data. Measurements of aerosol properties conducted at low relative humidity over the Bondville site compare well with the analogous surface aerosol data and do not indicate any major sampling issues or that the aerosol is radically different at the surface compared with the lowest flyby altitude of ~ 240 m above ground level. Statistical analyses of the in situ vertical profile data indicate that aerosol light scattering and absorption (related to aerosol amount decreases substantially with increasing altitude. Parameters related to the nature of the aerosol (e.g., single-scattering albedo, Ångström exponent, etc., however, are relatively constant throughout the mixed layer, and do not vary as much as the aerosol amount throughout the profile. While individual profiles often showed more variability, the median in situ single-scattering albedo was 0.93–0.95 for all sampled altitudes. Several parameters (e.g., submicrometer scattering fraction, hemispheric backscattering fraction, and

  16. Surface profiling interferometer

    Science.gov (United States)

    Takacs, Peter Z.; Qian, Shi-Nan

    1989-01-01

    The design of a long-trace surface profiler for the non-contact measurement of surface profile, slope error and curvature on cylindrical synchrotron radiation (SR) mirrors. The optical system is based upon the concept of a pencil-beam interferometer with an inherent large depth-of-field. The key feature of the optical system is the zero-path-difference beam splitter, which separates the laser beam into two colinear, variable-separation probe beams. A linear array detector is used to record the interference fringe in the image, and analysis of the fringe location as a function of scan position allows one to reconstruct the surface profile. The optical head is mounted on an air bearing slide with the capability to measure long aspheric optics, typical of those encountered in SR applications. A novel feature of the optical system is the use of a transverse "outrigger" beam which provides information on the relative alignment of the scan axis to the cylinder optic symmetry axis.

  17. Oxygen 18 concentration profile measurements near the surface by 18O(p,α)15N resonance reaction

    International Nuclear Information System (INIS)

    Amsel, G.; David, D.

    1975-01-01

    The method of spectrum reduction in nuclear reaction microanalysis does not allow to obtain depth resolutions better than the order of 2000A. Resolutions of the order of 200A may be obtained by using the narrow resonance technique, when applied to thin films. The latter technique was extended to thick targets, with deep concentration profiles presenting a sharp gradient near the surface. This method is presented and illustrated by the study of 18 O profiles in oxygen diffusion measurements in growing ZrO 2 , using the 629keV resonance of the reaction 18 O(p,α) 15 N [fr

  18. New twist in the optical schematic of surface slope measuring long trace profiler

    Science.gov (United States)

    Nikitin, Sergey M.; Gevorkyan, Gevork S.; McKinney, Wayne R.; Lacey, Ian; Takacs, Peter Z.; Yashchuk, Valeriy V.

    2017-09-01

    The advents of fully coherent free electron lasers and diffraction limited synchrotron storage ring sources of x-rays are catalyzing the development of new, ultra-high accuracy metrology methods. To fully exploit the potential of these sources, metrology needs to be capable of determining the figure of an optical element with sub-nanometer height accuracy. Currently, the two most prevalent slope measuring instruments used for characterization of x-ray optics are the auto-collimator based nanometer optical measuring device (NOM) and the long trace profiler (LTP) using pencil beam interferometry (PBI). These devices have been consistently improved upon by the x-ray optics metrology community, but appear to be approaching their metrological limits. Here, we revise the traditional optical schematic of the LTP. We experimentally show that, for the level of accuracy desired for metrology with state-of-the-art x-ray optics, the Dove prism in the LTP reference channel appears to be one of the major sources of instrumental error. Therefore, we suggest returning back to the original PBI LTP schematics with no Dove prism in the reference channel. In this case, the optimal scanning strategies [Yashchuk, Rev. Sci. Instrum. 80, 115101 (2009)] used to suppress the instrumental drift error have to be used to suppress a possible drift error associated with laser beam pointing instability. We experimentally and by numerical simulation demonstrate the usefulness of the suggested approach for measurements with x-ray optics with both face up and face down orientations.

  19. Water vapor profiling over ocean surface with 90 GHz and 183 GHz measurements under clear and cloudy conditions

    Science.gov (United States)

    Wang, J. R.; Sharma, A. K.

    1992-01-01

    Radiometric measurements at 90 GHz and three sideband frequencies near the peak water vapor absorption line of 183.3 GHz were made with the Advanced Microwave Moisture Sounder (AMMS) aboard the NASA DC-8 aircraft over some regions of the Pacific Ocean. These measurements were used to retrieve atmospheric water vapor profiles over ocean surface using the algorithm developed by Schaerer and Wilheit (1979). The algorithm incorporates a mechanism to estimate cloud liquid water when the estimated relative humidity is greater than 95 percent. The results are compared with estimated values from measurements taken by the Special Sensor Microwave/Imager (SSMI) and TIROS Operational Vertical Sounder (TOVS). The water vapor profiles estimated from AMMS are generally higher at low altitudes and lower at high altitudes than those from the TOVS measurements. Cloud liquid water is retrieved from both AMMS and SSM/I measurements over the same general regions. The retrieved water vapor profiles show more fluctuations in these regions. It is concluded that the AMMS with only four channels of measurements may not be able to retrieve both water vapor and cloud information with authority.

  20. Use of In Situ Cloud Condensation Nuclei, Extinction, and Aerosol Size Distribution Measurements to Test a Method for Retrieving Cloud Condensation Nuclei Profiles From Surface Measurements

    Science.gov (United States)

    Ghan, Stephen J.; Rissman, Tracey A.; Ellman, Robert; Ferrare, Richard A.; Turner, David; Flynn, Connor; Wang, Jian; Ogren, John; Hudson, James; Jonsson, Haflidi H.; hide

    2006-01-01

    If the aerosol composition and size distribution below cloud are uniform, the vertical profile of cloud condensation nuclei (CCN) concentration can be retrieved entirely from surface measurements of CCN concentration and particle humidification function and surface-based retrievals of relative humidity and aerosol extinction or backscatter. This provides the potential for long-term measurements of CCN concentrations near cloud base. We have used a combination of aircraft, surface in situ, and surface remote sensing measurements to test various aspects of the retrieval scheme. Our analysis leads us to the following conclusions. The retrieval works better for supersaturations of 0.1% than for 1% because CCN concentrations at 0.1% are controlled by the same particles that control extinction and backscatter. If in situ measurements of extinction are used, the retrieval explains a majority of the CCN variance at high supersaturation for at least two and perhaps five of the eight flights examined. The retrieval of the vertical profile of the humidification factor is not the major limitation of the CCN retrieval scheme. Vertical structure in the aerosol size distribution and composition is the dominant source of error in the CCN retrieval, but this vertical structure is difficult to measure from remote sensing at visible wavelengths.

  1. Measuring dose profiles and surface dose rates of sealed pure-beta sources to determine radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Seongmoon; Choi, Chang Heon; Ye, Sung-Joon [Seoul National University, Seoul (Korea, Republic of)

    2015-05-15

    A beta-emitter of radioisotope has been used for therapeutics and diagnostics in medicine. This radionuclide has been also used as fertilizer tracking, thickness gauges and nuclear battery in industrial application . In other words, the demand for associated radioisotope industry has been rising. One of the most important specifications of radioisotope is a radioactivity. Therefore, determining the methodology of radioactivity assay is also becoming an important procedure. The advancement of the sciences associated with radiation detection has contributed to the development of more sensitive, reliable and user friendly calibration systems. The gas-flow proportional counters, liquid scintillation counters, HP-Ge detectors and ionization chambers have been considered to be necessary for the primary calibration systems of radioactivity. The proportional counter is a type of gas-filled detector and designed to measure a detector output that is proportional to the incident radiation energy. The method developed in this study was applied to determine a radioactivity of Sr/Y-90 test source. The radioactivity determined by this method was about 39% lower than one reported by the manufacturer. This difference might result from the lack of accuracy in determining the radioactivity of the original source liquid and the amount of liquid dropped on the absorbent disk. Furthermore, accuracy in the calculated conversion factor mainly relies on how closely to simulate a sealed source and a detector in MCNP.

  2. Measurements of Near Sea Surface Infrared Propagation

    National Research Council Canada - National Science Library

    Frost, Shaun

    1999-01-01

    .... Measurements have been made of the atmospheric infrared transmission near the sea surface. Spectral transmission profiles were measured for a number of ranges using a fourier transform spectrometer...

  3. An innovative rotational Raman lidar to measure the temperature profile from the surface to 30 km altitude

    Science.gov (United States)

    Hauchecorne, Alain; Keckhut, Philippe; Mariscal, Jean-François; d'Almeida, Eric; Dahoo, Pierre-Richard; Porteneuve, Jacques

    2016-06-01

    A concept of innovative rotational Raman lidar with daylight measurement capability is proposed to measure the vertical profile of temperature from the ground to the middle stratosphere. The optical filtering is made using a Fabry-Pérot Interferometer with line spacing equal to the line spacing of the Raman spectrum. The detection is made using a linear PMT array operated in photon counting mode. We plan to build a prototype and to test it at the Haute-Provence Observatory lidar facility. to achieve a time resolution permitting the observation of small-scale atmospheric processes playing a role in the troposphere-stratosphere interaction as gravity waves. If successful, this project will open the possibility to consider a Raman space lidar for the global observation of atmospheric temperature profiles.

  4. An innovative rotational Raman lidar to measure the temperature profile from the surface to 30 km altitude

    Directory of Open Access Journals (Sweden)

    Hauchecorne Alain

    2016-01-01

    Full Text Available A concept of innovative rotational Raman lidar with daylight measurement capability is proposed to measure the vertical profile of temperature from the ground to the middle stratosphere. The optical filtering is made using a Fabry-Pérot Interferometer with line spacing equal to the line spacing of the Raman spectrum. The detection is made using a linear PMT array operated in photon counting mode. We plan to build a prototype and to test it at the Haute-Provence Observatory lidar facility. to achieve a time resolution permitting the observation of small-scale atmospheric processes playing a role in the troposphere-stratosphere interaction as gravity waves. If successful, this project will open the possibility to consider a Raman space lidar for the global observation of atmospheric temperature profiles.

  5. Athletes trained using stable compared to unstable surfaces exhibit distinct postural control profiles when assessed by traditional and nonlinear measures.

    Science.gov (United States)

    Powell, Douglas W; Williams, D S Blaise

    2015-12-01

    Athletes are assumed to exhibit better balance than non-athletes; however, few studies have examined the role of different types of sports on balance measures. Two athlete groups that experience divergent sport-specific balance training are stable- (i.e. basketball) and unstable-surface athletes (i.e. surfers). The purpose of this study was to quantify the effect of stable- compared to unstable-surface sports on postural stability. Eight non-athletes (NON), eight stable-surface athletes (SSA) and eight unstable-surface athletes (USA) performed five 20-s quiet standing trials while ground reaction forces were recorded. Approximate entropy (ApEn), total excursion and root mean square distances (RMS) of the center of pressure position were calculated. Univariate ANOVAs with post hoc tests were conducted for each variable. ApEn values were lower in SSA compared to NON in the ML direction (p=0.012) and USA had lower ApEn values compared to SSA in the AP direction (p=0.036). The USA had smaller AP RMS compared to SSA (p=0.002) while the USA had greater ML RMS (p=0.008) and resultant RMS values compared to SSA (p=0.025). These data suggest that USA and SSA may exhibit direction-specific differences in balance strategy due to feedback paradigm. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. All-silicon Michelson instrument on chip: Distance and surface profile measurement and prospects for visible light spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Malak, M.; Marty, F.; Bourouina, T. [Universite Paris-Est, Laboratoire ESYCOM, ESIEE Paris, Cite Descartes, 2 Boulevard Blaise Pascal, 93162 Noisy-le-Grand Cedex (France); Nouira, H.; Vailleau, G. [Laboratoire National de Metrologie et d' Essais, 1 rue Gaston Boissier, 75724 Paris Cedex 15 (France)

    2013-04-08

    A miniature Michelson interferometer is analyzed theoretically and experimentally. The fabricated micro-interferometer is incorporated at the tip of a monolithic silicon probe to achieve contactless distance measurements and surface profilometry. For infrared operation, two approaches are studied, based on the use of monochromatic light and wavelength sweep, respectively. A theoretical model is devised to depict the system characteristics taking into account Gaussian beam divergence and light spot size. Furthermore, preliminary results using visible light demonstrate operation of the probe as a visible light spectrometer, despite silicon absorbance, thanks to the micrometer thickness involved in the beam splitter.

  7. All-silicon Michelson instrument on chip: Distance and surface profile measurement and prospects for visible light spectrometry

    International Nuclear Information System (INIS)

    Malak, M.; Marty, F.; Bourouina, T.; Nouira, H.; Vailleau, G.

    2013-01-01

    A miniature Michelson interferometer is analyzed theoretically and experimentally. The fabricated micro-interferometer is incorporated at the tip of a monolithic silicon probe to achieve contactless distance measurements and surface profilometry. For infrared operation, two approaches are studied, based on the use of monochromatic light and wavelength sweep, respectively. A theoretical model is devised to depict the system characteristics taking into account Gaussian beam divergence and light spot size. Furthermore, preliminary results using visible light demonstrate operation of the probe as a visible light spectrometer, despite silicon absorbance, thanks to the micrometer thickness involved in the beam splitter.

  8. Surface Aerodynamic Temperature Derived from Wind/Termperature Profile Measurements Over Cotton and Alfalfa in a Semi-Arid Environment

    Science.gov (United States)

    Assessing the project efficiency of irrigation systems and water use efficiency of crops over large irrigated areas requires daily or seasonal evapotranspiration (ET) maps. Mapping ET or latent heat flux (LE) can be achieved spatially for land surfaces using remote sensing inputs such as surface ref...

  9. Surface cleanliness measurement procedure

    Science.gov (United States)

    Schroder, Mark Stewart; Woodmansee, Donald Ernest; Beadie, Douglas Frank

    2002-01-01

    A procedure and tools for quantifying surface cleanliness are described. Cleanliness of a target surface is quantified by wiping a prescribed area of the surface with a flexible, bright white cloth swatch, preferably mounted on a special tool. The cloth picks up a substantial amount of any particulate surface contamination. The amount of contamination is determined by measuring the reflectivity loss of the cloth before and after wiping on the contaminated system and comparing that loss to a previous calibration with similar contamination. In the alternative, a visual comparison of the contaminated cloth to a contamination key provides an indication of the surface cleanliness.

  10. Airborne Surface Profiling of Alaskan Glaciers

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of glacier outline, laser altimetry profile, and surface elevation change data for 46 glaciers in Alaska and British Columbia, Canada,...

  11. Long trace profile measurements on cylindrical aspheres

    International Nuclear Information System (INIS)

    Takacs, P.Z.; Feng, S.C.K.; Qian, S.N.; Liu, W.M.

    1988-01-01

    A new long-trace optical profiling instrument is now in operation at Brookhaven National Laboratory measuring surface figure and macro-roughness on large optical components, principally long cylindrical mirrors for use in synchrotron radiation beam lines. The non-contact measurement technique is based upon a pencil-beam interferometer system The optical head is mounted on a linear air bearing slide and has a free travel range of nearly one meter. The authors are able to sample surface spatial periods between 1 mm (the laser beam diameter) and 1 m. The input slope data is converted to surface height by a Fourier filtering technique. A number of optical components have been measured with the instrument. Results are presented for fused silica cylinders 900 mm and 600 mm in length and for a fused silica toroid and several electrodes nickel-plated paraboloids

  12. Gyral Folding Pattern Analysis via Surface Profiling

    Science.gov (United States)

    Li, Kaiming; Guo, Lei; Li, Gang; Nie, Jingxin; Faraco, Carlos; Cui, Guangbin; Zhao, Qun; Miller, L. Stephen; Liu, Tianming

    2010-01-01

    Folding is an essential shape characteristic of the human cerebral cortex. Descriptors of cortical folding patterns have been studied for decades. However, many previous studies are either based on local shape descriptors such as curvature, or based on global descriptors such as gyrification index or spherical wavelets. This paper proposes a gyrus-scale folding pattern analysis technique via cortical surface profiling. Firstly, we sample the cortical surface into 2D profiles and model them using a power function. This step provides both the flexibility of representing arbitrary shape by profiling and the compactness of representing shape by parametric modeling. Secondly, based on the estimated model parameters, we extract affine-invariant features on the cortical surface, and apply the affinity propagation clustering algorithm to parcellate the cortex into cortical regions with strict hierarchy and smooth transitions among them. Finally, a second-round surface profiling is performed on the parcellated cortical surface, and the number of hinges is detected to describe the gyral folding pattern. We have applied the surface profiling method to two normal brain datasets and a Schizophrenia patient dataset. The experimental results demonstrate that the proposed method can accurately classify human gyri into 2-hinge, 3-hinge and 4-hinge patterns. The distribution of these folding patterns on brain lobes and the relationship between fiber density and gyral folding patterns are further investigated. Results from the Schizophrenia dataset are consistent with commonly found abnormality in former studies by others, which demonstrates the potential clinical applications of the proposed technique. PMID:20472071

  13. Surface glycosylation profiles of urine extracellular vesicles.

    Directory of Open Access Journals (Sweden)

    Jared Q Gerlach

    Full Text Available Urinary extracellular vesicles (uEVs are released by cells throughout the nephron and contain biomolecules from their cells of origin. Although uEV-associated proteins and RNA have been studied in detail, little information exists regarding uEV glycosylation characteristics. Surface glycosylation profiling by flow cytometry and lectin microarray was applied to uEVs enriched from urine of healthy adults by ultracentrifugation and centrifugal filtration. The carbohydrate specificity of lectin microarray profiles was confirmed by competitive sugar inhibition and carbohydrate-specific enzyme hydrolysis. Glycosylation profiles of uEVs and purified Tamm Horsfall protein were compared. In both flow cytometry and lectin microarray assays, uEVs demonstrated surface binding, at low to moderate intensities, of a broad range of lectins whether prepared by ultracentrifugation or centrifugal filtration. In general, ultracentrifugation-prepared uEVs demonstrated higher lectin binding intensities than centrifugal filtration-prepared uEVs consistent with lesser amounts of co-purified non-vesicular proteins. The surface glycosylation profiles of uEVs showed little inter-individual variation and were distinct from those of Tamm Horsfall protein, which bound a limited number of lectins. In a pilot study, lectin microarray was used to compare uEVs from individuals with autosomal dominant polycystic kidney disease to those of age-matched controls. The lectin microarray profiles of polycystic kidney disease and healthy uEVs showed differences in binding intensity of 6/43 lectins. Our results reveal a complex surface glycosylation profile of uEVs that is accessible to lectin-based analysis following multiple uEV enrichment techniques, is distinct from co-purified Tamm Horsfall protein and may demonstrate disease-specific modifications.

  14. Ion induced optical emission for surface and depth profile analysis

    International Nuclear Information System (INIS)

    White, C.W.

    1977-01-01

    Low-energy ion bombardment of solid surfaces results in the emission of infrared, visible, and ultraviolet radiation produced by inelastic ion-solid collision processes. The emitted optical radiation provides important insight into low-energy particle-solid interactions and provides the basis for an analysis technique which can be used for surface and depth profile analysis with high sensitivity. The different kinds of collision induced optical radiation emitted as a result of low-energy particle-solid collisions are reviewed. Line radiation arising from excited states of sputtered atoms or molecules is shown to provide the basis for surface and depth profile analysis. The spectral characteristics of this type of radiation are discussed and applications of the ion induced optical emission technique are presented. These applications include measurements of ion implant profiles, detection sensitivities for submonolayer quantities of impurities on elemental surfaces, and the detection of elemental impurities on complex organic substrates

  15. Velocity profiles of fluid flow close to a hydrophobic surface

    Science.gov (United States)

    Fialová, Simona; Pochylý, František; Kotek, Michal; Jašíková, Darina

    The results of research on viscous liquid flow upon a superhydrophobic surface are presented in the paper. In the introduction, the degrees of surface hydrophobicity in correlation with an adhesion coefficient are defined. The usage of the adhesion coefficient for the definition of a new boundary condition is employed for expressing the slip of the liquid over the superhydrophobic surface. The slip of the liquid was identified on a special experimental device. The essence of the device consists of a tunnel of rectangular cross section whose one wall is treated with a superhydrophobic layer. The other walls are made of transparent organic glass whose surface is hydrophilic. Velocity profiles are measured by PIV. The methodology is drawn so that it allows the speed determination at the closest point to the wall. The measurements were performed for different Reynolds numbers for both laminar and turbulent flow. Based on the measured velocity profiles, marginal terms of use have been verified, expressing slippage of the liquid on the wall. New forms of velocity profiles considering superhydrophobic surfaces are shown within the work.

  16. Carbon nanotube oscillator surface profiling device and method of use

    Science.gov (United States)

    Popescu, Adrian [Tampa, FL; Woods, Lilia M [Tampa, FL; Bondarev, Igor V [Fuquay Varina, NC

    2011-11-15

    The proposed device is based on a carbon nanotube oscillator consisting of a finite length outer stationary nanotube and a finite length inner oscillating nanotube. Its main function is to measure changes in the characteristics of the motion of the carbon nanotube oscillating near a sample surface, and profile the roughness of this surface. The device operates in a non-contact mode, thus it can be virtually non-wear and non-fatigued system. It is an alternative to the existing atomic force microscope (AFM) tips used to scan surfaces to determine their roughness.

  17. Surface texture measurement for additive manufacturing

    International Nuclear Information System (INIS)

    Triantaphyllou, Andrew; Tomita, Ben; Milne, Katherine A; Giusca, Claudiu L; Macaulay, Gavin D; Roerig, Felix; Hoebel, Matthias; Leach, Richard K

    2015-01-01

    The surface texture of additively manufactured metallic surfaces made by powder bed methods is affected by a number of factors, including the powder’s particle size distribution, the effect of the heat source, the thickness of the printed layers, the angle of the surface relative to the horizontal build bed and the effect of any post processing/finishing. The aim of the research reported here is to understand the way these surfaces should be measured in order to characterise them. In published research to date, the surface texture is generally reported as an Ra value, measured across the lay. The appropriateness of this method for such surfaces is investigated here. A preliminary investigation was carried out on two additive manufacturing processes—selective laser melting (SLM) and electron beam melting (EBM)—focusing on the effect of build angle and post processing. The surfaces were measured using both tactile and optical methods and a range of profile and areal parameters were reported. Test coupons were manufactured at four angles relative to the horizontal plane of the powder bed using both SLM and EBM. The effect of lay—caused by the layered nature of the manufacturing process—was investigated, as was the required sample area for optical measurements. The surfaces were also measured before and after grit blasting. (paper)

  18. Measurement of kinaesthetic properties of in-brine table olives by microstructure of fracture surface, sensory evaluation and texture profile analysis (TPA).

    Science.gov (United States)

    Lanza, Barbara; Amoruso, Filomena

    2018-02-02

    A series of transformations occur in olive fruit both during ripening and processing. In particular, significant changes in the microstructural composition affect the flavour, texture, nutrients and overall quality of the end product. Texture is one of the sensory quality attributes of greatest importance to consumer acceptance. In the present work, kinaesthetic properties of in-brine table olives of three cultivars of Olea europaea L. (Bella di Cerignola, Peranzana and Taggiasca cvs) were provided by several measurements of olive tissue texture by sensory, rheological and microstructural approaches. Olives at the same stage of ripening and processed with the same technology, but belonging to different cultivars, showed significant differences at microstructural, sensorial and rheological levels. To describe the relationship between the three variables, multiple regression analysis and principal component analysis were chosen. Differences in microstructure were closely related both in terms of hardness measured by texture profile analysis and hardness measured by sensory analysis. The information provided could be an aid for screening and training of a sensory panel. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  19. Reducing Surface Clutter in Cloud Profiling Radar Data

    Science.gov (United States)

    Tanelli, Simone; Pak, Kyung; Durden, Stephen; Im, Eastwood

    2008-01-01

    An algorithm has been devised to reduce ground clutter in the data products of the CloudSat Cloud Profiling Radar (CPR), which is a nadir-looking radar instrument, in orbit around the Earth, that measures power backscattered by clouds as a function of distance from the instrument. Ground clutter contaminates the CPR data in the lowest 1 km of the atmospheric profile, heretofore making it impossible to use CPR data to satisfy the scientific interest in studying clouds and light rainfall at low altitude. The algorithm is based partly on the fact that the CloudSat orbit is such that the geodetic altitude of the CPR varies continuously over a range of approximately 25 km. As the geodetic altitude changes, the radar timing parameters are changed at intervals defined by flight software in order to keep the troposphere inside a data-collection time window. However, within each interval, the surface of the Earth continuously "scans through" (that is, it moves across) a few range bins of the data time window. For each radar profile, only few samples [one for every range-bin increment ((Delta)r = 240 m)] of the surface-clutter signature are available around the range bin in which the peak of surface return is observed, but samples in consecutive radar profiles are offset slightly (by amounts much less than (Delta)r) with respect to each other according to the relative change in geodetic altitude. As a consequence, in a case in which the surface area under examination is homogenous (e.g., an ocean surface), a sequence of consecutive radar profiles of the surface in that area contains samples of the surface response with range resolution (Delta)p much finer than the range-bin increment ((Delta)p data acquired over an ocean surface. A preliminary analysis of the test data showed a surface-clutter-rejection ratio over flat surfaces of >10 dB and a reduction of the contaminated altitude over ocean from about 1 km to about 0.5 km (over the ocean). The algorithm has been embedded

  20. Tools for measuring surface cleanliness

    Energy Technology Data Exchange (ETDEWEB)

    Schroder, Mark Stewart (Hendersonville, NC); Woodmansee, Donald Ernest (Simpsonville, SC); Beadie, Douglas Frank (Greenville, SC)

    2002-01-01

    A procedure and tools for quantifying surface cleanliness are described. Cleanliness of a target surface is quantified by wiping a prescribed area of the surface with a flexible, bright white cloth swatch, preferably mounted on a special tool. The cloth picks up a substantial amount of any particulate surface contamination. The amount of contamination is determined by measuring the reflectivity loss of the cloth before and after wiping on the contaminated system and comparing that loss to a previous calibration with similar contamination. In the alternative, a visual comparison of the contaminated cloth to a contamination key provides an indication of the surface cleanliness.

  1. Velocity profiles and surface roughness under breaking waves

    Science.gov (United States)

    Craig, Peter D.

    1996-01-01

    Recent measurements under wave-breaking conditions in the ocean, lakes, and tanks reveal a layer immediately below the surface in which dissipation decays as depth to the power -2 to -4 and downwind velocities are approximately linear with depth. This behavior is consistent with predictions of a conventional, one-dimensional, level 2.5 turbulence closure model, in which the influence of breaking waves is parameterized as a surface source of turbulent kinetic energy. The model provides an analytic solution which describes the near-surface power law behavior and the deeper transition to the "law of the wall." The mixing length imposed in the model increases linearly away from a minimum value, the roughness length, at the surface. The surface roughness emerges as an important scaling factor in the wave-enhanced layer but is the major unknown in the formulation. Measurements in the wave-affected layer are still rare, but one exceptional set, both in terms of its accuracy and proximity to the surface, is that collected by Cheung and Street [1988] in the Stanford wind tunnel. Their velocity profiles first confirm the accuracy of the model, and, second, allow estimation, via a best fit procedure, of roughness lengths at five different wind speeds. Conclusions are tentative but indicate that the roughness length increases with wind speed and appears to take a value of approximately one sixth the dominant surface wavelength. A more traditional wall-layer model, which ignores the flux of turbulent kinetic energy, will also accurately reproduce the measured velocity profiles. In this case, enhanced surface turbulence is forced on the model by the assumption of a large surface roughness, three times that required by the full model. However, the wall-layer model cannot predict the enhanced dissipation near the surface.

  2. Application of genetic algorithm in the evaluation of the profile error of archimedes helicoid surface

    Science.gov (United States)

    Zhu, Lianqing; Chen, Yunfang; Chen, Qingshan; Meng, Hao

    2011-05-01

    According to minimum zone condition, a method for evaluating the profile error of Archimedes helicoid surface based on Genetic Algorithm (GA) is proposed. The mathematic model of the surface is provided and the unknown parameters in the equation of surface are acquired through least square method. Principle of GA is explained. Then, the profile error of Archimedes Helicoid surface is obtained through GA optimization method. To validate the proposed method, the profile error of an Archimedes helicoid surface, Archimedes Cylindrical worm (ZA worm) surface, is evaluated. The results show that the proposed method is capable of correctly evaluating the profile error of Archimedes helicoid surface and satisfy the evaluation standard of the Minimum Zone Method. It can be applied to deal with the measured data of profile error of complex surface obtained by three coordinate measurement machines (CMM).

  3. The Use of 2D Plastic Grating for Surface Profile and Dimension Manufacture Product Measurements by Using NDT Moiré Technique

    Directory of Open Access Journals (Sweden)

    Retno Wigajatri Purnamaningsih

    2010-10-01

    Full Text Available Research of measuring the shape and dimension of object using the moiré technique have been done. Measurement have been made by observing the moiré space as a result of interaction between grating and its shadow casted on the object's surface caused by the projector lamp with CCD camera. The acquired data was further processed by way of off-line. By successive phase shifts that is π/2, π dan 3π/2 towards the table tennis ball at the distance of 48 cm from the light source and CCD camera, with the distance between CCD Camera and light source 13,5 cm and grating space 0,5 mm. It was obtained that convex shape can be identified by resolution of 0,24 mm. It was also shown that the biggest difference between the results of using moiré technique and the use of CMM contact measurements (Coordinate Measuring Machine was 0,3 mm

  4. Armor Plate Surface Roughness Measurements

    National Research Council Canada - National Science Library

    Stanton, Brian; Coburn, William; Pizzillo, Thomas J

    2005-01-01

    ...., surface texture and coatings) that could become important at high frequency. We measure waviness and roughness of various plates to know the parameter range for smooth aluminum and rolled homogenous armor (RHA...

  5. Regional surface fluxes from satellite-derived surface temperatures (AVHRR) and radiosonde profiles

    Science.gov (United States)

    Brutsaert, Wilfried; Sugita, Michiaki

    1992-01-01

    Radiometric surface temperatures, derived from measurements by the AVHRR instrument aboard the NOAA-9 and the NOAA-11 polar orbiting satellites, were used in combination with wind velocity and temperature profiles measured by radiosondes, to calculate surface fluxes of sensible heat. The measurements were made during FIFE, the First ISLSCP (International Satellite Land Surface Climatology Project) Field Experiment, in a hilly tall grass prairie area of northeastern Kansas. The method of calculation was based on turbulent similarity formulations for the atmospheric boundary layer. Good agreement (r = 0.7) was obtained with reference values of sensible heat flux, taken as arithmetric means of measurements with the Bowen ratio method at six ground stations. The values of evaporation (latent heat fluxes), derived from these sensible heat fluxes by means of the energy budget, were also in good agreement (r = 0.94) with the corresponding reference values from the ground stations.

  6. Turbulent heat fluxes by profile and inertial dissipation methods: analysis of the atmospheric surface layer from shipboard measurements during the SOFIA/ASTEX and SEMAPHORE experiments

    Directory of Open Access Journals (Sweden)

    H. Dupuis

    Full Text Available Heat flux estimates obtained using the inertial dissipation method, and the profile method applied to radiosonde soundings, are assessed with emphasis on the parameterization of the roughness lengths for temperature and specific humidity. Results from the inertial dissipation method show a decrease of the temperature and humidity roughness lengths for increasing neutral wind speed, in agreement with previous studies. The sensible heat flux estimates were obtained using the temperature estimated from the speed of sound determined by a sonic anemometer. This method seems very attractive for estimating heat fluxes over the ocean. However allowance must be made in the inertial dissipation method for non-neutral stratification. The SOFIA/ASTEX and SEMAPHORE results show that, in unstable stratification, a term due to the transport terms in the turbulent kinetic energy budget, has to be included in order to determine the friction velocity with better accuracy. Using the profile method with radiosonde data, the roughness length values showed large scatter. A reliable estimate of the temperature roughness length could not be obtained. The humidity roughness length values were compatible with those found using the inertial dissipation method.

  7. Surface Layer Turbulence and Aerosol Profiles During MAPTIP

    NARCIS (Netherlands)

    Davidson, K.L.; Frederickson, P.A.; Leeuw, G. de

    1995-01-01

    The Naval Postgraduate School (NPS) and the TNO Physics and Electronics Laboratory (TNO-FEL) deployed in situ sensors near and on Meetpost Noordwijk (MPN) during MAPTIP to describe the surface layer processes and also to evaluate models for near-surface aerosol profiles. Vertical profiles of aerosol

  8. Oceanographic profile chlorophyll, nutrients and other measurements collected using surface seawater intake from the Caribbean, Pacific and Atlantic Ocean from 1999 - 2002 (NODC Accession 0001009)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A set of phytoplankton pigment measurements collected on eight quarterly transects from France to New Caledonia is analyzed in order to identify the main assemblages...

  9. A variable-resolution optical profile measurement system

    Science.gov (United States)

    Tsai, Tung-Hsien; Fan, Kuang-Chao; Mou, Jong-I.

    2002-02-01

    In this study, a variable-resolution optical measurement system (VROPMS) based on triangulation measurement technology is proposed. The VROPMS optical scanning probe is composed of dual CCD cameras fitted with zoom lenses and a line laser diode projector. A flexible and novel calibration procedure for VROPMS is developed to acquire the system parameters quickly and accurately. The central position of the reflected laser image is calculated using Gaussian function least-squares fitting of the beam intensity. Subpixel resolution can thus be acquired. Experimental calibration results show that the higher the lens magnification, the finer the derived system resolution. The best accuracy at the zoomed focus position is about 0.02 mm. This system can flexibly zoom in or out to measure a 3D object profile in sections according to the approximate surface profile. Varied mesh images taken from different zoom positions by VROPMS can be patched using the image matching technique to reconstruct the entire profile. A human sculpture with a complex surface profile is measured using VROPMS as a practical illustration of the effectiveness of the system.

  10. Quantitative sputter profiling at surfaces and interfaces

    International Nuclear Information System (INIS)

    Kirschner, J.; Etzkorn, H.W.

    1981-01-01

    The key problem in quantitative sputter profiling, that of a sliding depth scale has been solved by combined Auger/X-ray microanalysis. By means of this technique and for the model system Ge/Si (amorphous) the following questions are treated quantitatively: shape of the sputter profiles when sputtering through an interface and origin of their asymmetry; precise location of the interface plane on the depth profile; broadening effects due to limited depth of information and their correction; origin and amount of bombardment induced broadening for different primary ions and energies; depth dependence of the broadening, and basic limits to depth resolution. Comparisons are made to recent theoretical calculations based on recoil mixing in the collision cascade and very good agreement is found

  11. Surface, segregation profile for Ni50Pd50(100)

    DEFF Research Database (Denmark)

    Christensen, Asbjørn; Ruban, Andrei; Skriver, Hans Lomholt

    1997-01-01

    A recent dynamical LEED study [G.N. Derry, C.B. McVey, P.J. Rous, Surf. Sci. 326 (1995) 59] reported an oscillatory surface segregation profile in the Ni50Pd50(100) system with the surface layer enriched by Pd. We have performed ab-initio total-energy calculations for the surface of this alloy...... system using the coherent potential approximation and obtain an oscillatory segregation profile, in agreement with experiments. We discuss the energetic origin of the oscillatory segregation profile in terms of effective cluster interactions. We include relaxation effects by means of the semi...

  12. Planarization Profile Measurement Using A Confocal Scanning Laser Microscope

    Science.gov (United States)

    Smith, Ian R.; Bennett, Simon D.; Lindow, James T.; Monahan, Kevin

    1986-08-01

    The use of planarizing layers to improve the performance of photolithography for micron and submicron devices is being actively explored by a number of semiconductor companies. The usefulness of the procedure depends critically upon the degree to which residual surface undulations can be controlled. This paper describes how a confocal scanning optical microscope may be used to measure surface profiles of planarizing layers and discusses the factors which influence the accuracy of measurement. Experimental measurements, using a SiScan-I system, of resist and P.S.G. planarizing layers are presented, demonstrating a sensitivity to surface height changes of 50 nm. The technique may be improved upon by careful design of the microscope and selection of the imaging wavelength. These factors are discussed.

  13. On the extension of the wind profile over homogeneous terrain beyond the surface boundary layer

    DEFF Research Database (Denmark)

    Gryning, Sven-Erik; Batchvarova, Ekaterina; Brümmer, B.

    2007-01-01

    Analysis of profiles of meteorological measurements from a 160 m high mast at the National Test Site for wind turbines at H phi vs phi re (Denmark) and at a 250 m high TV tower at Hamburg (Germany) shows that the wind profile based on surface-layer theory and Monin-Obukhov scaling is valid up to ...

  14. Surface Curvatures and Diffraction Profiles of Sagittaly Bent Laue Crystals

    Energy Technology Data Exchange (ETDEWEB)

    Shi, X.; Takacs, P.; Ghose, S.; Zhong, Z.; Rehak, M.L.; Kaznatcheev, K.; Dooryhee, E.

    2011-05-17

    The performance of a bent Laue crystal monochromator crucially depends on the sagittal and meridional bending curvatures of the crystal. To optimize the design of monochromator crystals, the surface curvatures and diffraction profiles of a set of sagittally bent Laue crystals with different aspect ratios have been studied experimentally by optical metrology and X-ray measurements. The results were confirmed with finite-element analysis using large-deformation theory. The nonlinear relationship between the curvatures necessitates an experimentally determined parameter in the theoretical modeling of the diffraction profiles. By taking into account the local stress and the aspect ratio of the sagittally bent Laue crystal, the modified analytical approach successfully predicts the rocking-curve width and the integrated reflecting power. The effect of extreme sagittal bending on the rocking curve is also discussed. To retain high reflectivity, the bending curvature should not exceed its critical value for the specified crystal geometry. Furthermore, the uniformity of the bending curvatures across the crystal surface has been examined, which suggests that the minimum crystal dimension should be approximately twice the size of the beam footprint.

  15. Nonequilibrium shock layer temperature profiles from arc jet radiation measurements

    Science.gov (United States)

    Blackwell, Harvel E.; Yuen, Eric; Scott, Carl D.; Arepalli, Sivaram

    1989-01-01

    Shock layer temperature profiles are obtained through analysis of radiation from shock layers produced by a blunt body inserted in arc jet flow. Spectral measurements have been made in a nitrogen flow of 54.4 gm/s at an enthalpy of 8.72 MJ/kg. Vibrational temperatures for N2+ are obtained by matching spectral regions from arc jet spectra with spectra generated using the NEQAIR code. Temperature profiles obtained from the radiation layers show a vibrational temperature higher than the rotational temperature near the front of the shock and both temperatures decrease as the flow approaches the body. The spectral measurements are made and analysis completed for four distances, from the surface of the blunt body. The corresponding shock layer thickness is approximately 3.6 cm. Although the shock layer appears to be in thermal nonequilibrium, the measured rotational temperature approaches the single temperature results of viscous shock layer calculations at this test condition.

  16. Flux surface shape and current profile optimization in tokamaks

    International Nuclear Information System (INIS)

    Dobrott, D.R.; Miller, R.L.

    1977-01-01

    Axisymmetric tokamak equilibria of noncircular cross section are analyzed numerically to study the effects of flux surface shape and current profile on ideal and resistive interchange stability. Various current profiles are examined for circles, ellipses, dees, and doublets. A numerical code separately analyzes stability in the neighborhood of the magnetic axis and in the remainder of the plasma using the criteria of Mercier and Glasser, Greene, and Johnson. Results are interpreted in terms of flux surface averaged quantities such as magnetic well, shear, and the spatial variation in the magnetic field energy density over the cross section. The maximum stable β is found to vary significantly with shape and current profile. For current profiles varying linearly with poloidal flux, the highest β's found were for doublets. Finally, an algorithm is presented which optimizes the current profile for circles and dees by making the plasma everywhere marginally stable

  17. Use of glow discharge in measurement of diffusion profile

    International Nuclear Information System (INIS)

    Baudin, Guy

    1976-05-01

    The composition of a glow discharge plasma is a good image of the composition of the surface being erroded without fusion. The depth of metal eated away is a linear function of time in 10 to 60μ range, that is too say between 2 and 20 minutes after lightning of the lamp. So measuring the emission of the discharge is function of time gives the diffusion profile of elements either by measuring instantaneous signal or by integrating during short periods of time for weak concentration. Examples of application for diffusion of N 2 and C in steel will be given [fr

  18. Measuring hydrogen-isotope distribution profiles

    International Nuclear Information System (INIS)

    Poppe, C.H.

    1977-01-01

    A new nondestructive technique was developed for measuring the depth distribution of hydrogen isotopes absorbed or implanted near the surface of any material. The method allows real-time study of the inventory and diffusion of hydrogen, deuterium, and tritium. Briefly, the technique involves bombarding the surface with a monoenergetic beam of ions chosen for their ability to react with the hydrogen isotope in question and produce fast neutrons. The energy distribution of the neutrons is a sensitive indicator of the energy of the bombarding particles at the instant of reaction, and hence of the depth of the reaction sites below he surface of the material. A sensitivity of one part per million was obtained for tritium in copper. The technique is applicable to several energy-related materials problems. 5 figures

  19. Radiometric measurement independent of profile. Belt weighers

    International Nuclear Information System (INIS)

    Otto, J.

    1986-01-01

    Radiometric measuring techniques allow contactless determination of the material carried by belt conveyors. Data defining the material is obtained via attenuation of gamma rays passing through the material on the belt. The method applies the absorption law according to Lambert-Beer, which has to be corrected by a build-up factor because of the stray radiation induced by the Compton effect. The profile-dependent error observed with conventional radiometric belt weighers is caused by the non-linearity of the absorption law in connection with the simultaneous summation of the various partial rays in a detector. The scanning method allows separate evaluation of the partial rays' attenuation and thus yields the correct data of the material carried, regardless of the profile. The scanning method is applied on a finite number of scanning sections, and a residual error has to be taken into account. The stochastics of quantum emission and absorption leads to an error whose expectation value is to be taken into account in the scanning algorithm. As the conveyor belt is in motion during the process of measurements, only part of the material conveyed is irradiated. The resulting assessment error is investigated as a function of the autocorrelation function of the material on the belt. (orig./HP) [de

  20. Interferometric Surface Relief Measurements with Subnano/Picometer Height Resolution

    Science.gov (United States)

    Sysoev, Evgeny; Kosolobov, Sergey; Kulikov, Rodion; Latyshev, Alexander; Sitnikov, Sergey; Vykhristyuk, Ignat

    2017-10-01

    We present an optical interference system nanoprofiler MNP-1 designed for high-precision noncontact measurement of surface relief with subnanometer resolution (root mean square of measured values), based on partial scanning of interference signal. The paper describes the construction of the measurement system with Linnik interferometer and the algorithm for nanorelief surface reconstruction. Experimental measurement results of silicon sample with profile height of surface structure of one interatomic distance obtained by MNP-1 are shown. It was proposed to use an atomically smooth surface as the reference mirror in the interferometer MNP-1 that allowed us to measure monatomic steps of the presented silicon sample. Monatomic steps of 0.31 nm in height on silicon (111) surface were measured with resolution up to 5 pm.

  1. Measurement of LBE flow velocity profile by UDVP

    International Nuclear Information System (INIS)

    Kikuchi, Kenji; Takeda, Yasushi; Obayashi, Hiroo; Tezuka, Masao; Sato, Hiroshi

    2006-01-01

    Measurements of liquid metal lead-bismuth eutectic (LBE), flow velocity profile were realized in the spallation neutron source target model by the ultrasonic Doppler velocity profiler (UVDP) technique. So far, it has not been done well, because both of poor wetting property of LBE with stainless steels and poor performance of supersonic probes at high temperatures. The measurement was made for a return flow in the target model, which has coaxially arranged annular and tube channels, in the JAEA Lead Bismuth Loop-2 (JLBL-2). The surface treatment of LBE container was examined. It was found that the solder coating was effective to enhance an intensity of reflected ultrasonic wave. This treatment has been applied to the LBE loop, which was operated up to 150 deg. C. The electro magnetic pump generates LBE flow and the flow rate was measured by the electro magnetic flow meter. By changing the flow rate of LBE, velocity profiles in the target were measured. It was confirmed that the maximum velocity in the time-averaged velocity distribution on the target axis was proportional to the flow rate measured by the electro magnetic flow meter

  2. The measurement of surface gravity

    International Nuclear Information System (INIS)

    Crossley, David; Hinderer, Jacques; Riccardi, Umberto

    2013-01-01

    This review covers basic theory and techniques behind the use of ground-based gravimetry at the Earth's surface. The orientation is toward modern instrumentation, data processing and interpretation for observing surface, land-based, time-variable changes to the geopotential. The instrumentation side is covered in some detail, with specifications and performance of the most widely used models of the three main types: the absolute gravimeters (FG5, A10 from Micro-g LaCoste), superconducting gravimeters (OSG, iGrav from GWR instruments), and the new generation of spring instruments (Micro-g LaCoste gPhone, Scintrex CG5 and Burris ZLS). A wide range of applications is covered, with selected examples from tides and ocean loading, atmospheric effects on gravity, local and global hydrology, seismology and normal modes, long period and tectonics, volcanology, exploration gravimetry, and some examples of gravimetry connected to fundamental physics. We show that there are only a modest number of very large signals, i.e. hundreds of µGal (10 −8 m s −2 ), that are easy to see with all gravimeters (e.g. tides, volcanic eruptions, large earthquakes, seasonal hydrology). The majority of signals of interest are in the range 0.1–5.0 µGal and occur at a wide range of time scales (minutes to years) and spatial extent (a few meters to global). Here the competing effects require a careful combination of different gravimeter types and measurement strategies to efficiently characterize and distinguish the signals. Gravimeters are sophisticated instruments, with substantial up-front costs, and they place demands on the operators to maximize the results. Nevertheless their performance characteristics such as drift and precision have improved dramatically in recent years, and their data recording ability and ruggedness have seen similar advances. Many subtle signals are now routinely connected with known geophysical effects such as coseismic earthquake displacements, post

  3. The measurement of surface gravity

    Science.gov (United States)

    Crossley, David; Hinderer, Jacques; Riccardi, Umberto

    2013-04-01

    This review covers basic theory and techniques behind the use of ground-based gravimetry at the Earth's surface. The orientation is toward modern instrumentation, data processing and interpretation for observing surface, land-based, time-variable changes to the geopotential. The instrumentation side is covered in some detail, with specifications and performance of the most widely used models of the three main types: the absolute gravimeters (FG5, A10 from Micro-g LaCoste), superconducting gravimeters (OSG, iGrav from GWR instruments), and the new generation of spring instruments (Micro-g LaCoste gPhone, Scintrex CG5 and Burris ZLS). A wide range of applications is covered, with selected examples from tides and ocean loading, atmospheric effects on gravity, local and global hydrology, seismology and normal modes, long period and tectonics, volcanology, exploration gravimetry, and some examples of gravimetry connected to fundamental physics. We show that there are only a modest number of very large signals, i.e. hundreds of µGal (10-8 m s-2), that are easy to see with all gravimeters (e.g. tides, volcanic eruptions, large earthquakes, seasonal hydrology). The majority of signals of interest are in the range 0.1-5.0 µGal and occur at a wide range of time scales (minutes to years) and spatial extent (a few meters to global). Here the competing effects require a careful combination of different gravimeter types and measurement strategies to efficiently characterize and distinguish the signals. Gravimeters are sophisticated instruments, with substantial up-front costs, and they place demands on the operators to maximize the results. Nevertheless their performance characteristics such as drift and precision have improved dramatically in recent years, and their data recording ability and ruggedness have seen similar advances. Many subtle signals are now routinely connected with known geophysical effects such as coseismic earthquake displacements, post-glacial rebound

  4. In vivo measurement of urethral dose profiles

    International Nuclear Information System (INIS)

    Toye, W.C.; Royal Melbourne Institute of Technology,; Duchesne, G.M.; Das, K.R.; Cee, A.; Mameghan, H.; Johnston, P.N.

    2001-01-01

    definition and translation variation, or gland edema) are not introduced as the TLD train must lay in the centre of the urethra. Typically, agreement between measured and predicted (localised by the position of brass spacers) urethral doses was ± 3%. On one occasion, after review of the measured profile, a treatment plan was subsequently altered for the remaining 3 treatment fractions. The urethral cavity provided an ideal location from which TLD in vivo measurements were made during HDR brachytherapy to the prostate. A method for obtaining a database of measured urethral dose profiles using routine in vivo TLD dosimetry is described. The in vivo measurements were in good agreement with profiles predicted by the dose planning algorithm. Copyright (2001) Australasian College of Physical Scientists and Engineers in Medicine

  5. Measurements of fusion product emission profiles in tokamaks

    International Nuclear Information System (INIS)

    Strachan, J.D.; Heidbrink, W.W.; Hendel, H.W.; Lovberg, J.; Murphy, T.J.; Nieschmidt, E.B.; Tait, G.D.; Zweben, S.J.

    1986-11-01

    The techniques and results of fusion product emission profile measurements are reviewed. While neutron source strength profile measurements have been attempted by several methods, neutron scattering is a limitation to the results. Profile measurements using charged fusion products have recently provided an alternative since collimation is much easier for the charged particles

  6. Transverse Beam Profile Measurements Using Optical Methods

    CERN Document Server

    Peters, A; Weiss, A; Bank, A

    2001-01-01

    Two different systems are currently under development at GSI's heavy ion facility to measure transverse beam profiles using optical emitters. At the GSI-LINAC for energies up to 15 MeV/u residual gas fluorescence is investigated for pulsed high current beams. The fluorescence of N2 is monitored by an image intensified CCD camera. For all ion species with energies above 50 MeV/u slowly extracted from the synchrotron SIS a classical viewing screen system is used. Three different target materials have been investigated and their behavior concerning efficiency, saturation and timing performance is evaluated. Both systems (will) use CCD cameras with a digital read out using the IEEE 1394 standard.

  7. Current density profile measurements in the Proto-Cleo Torsatron

    International Nuclear Information System (INIS)

    Schaeffer, R.C.; Shohet, J.L.

    1979-10-01

    Current density profile measurements were obtained in the Proto-Cleo Torsatron (R = 40 cm, a = 5 cm, l = 3, B/sub T/ = 3 kG, anti n approx. 10 11 cm -3 , T/sub e/ approx. 20 eV) by using a small, back-to-back flat double probe. Three different operating circuits used with this probe are presented, along with experimental results, all showing good agreement. Current is seen to flow only within the separatrix, in channels which follow the magnetic surfaces as they move radially inward with time due to changing vertical magnetic flux

  8. SGP Cloud and Land Surface Interaction Campaign (CLASIC): Measurement Platforms

    Energy Technology Data Exchange (ETDEWEB)

    MA Miller; R Avissar; LK Berg; SA Edgerton; ML Fischer; TJ Jackson; B. Kustas; PJ Lamb; G McFarquhar; Q Min; B Schmid; MS Torn; DD Tuner

    2007-06-01

    The Cloud and Land Surface Interaction Campaign (CLASIC) will be conducted from June 8 to June 30, 2007, at the U.S. Department of Energy’s Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) Southern Great Plains (SGP) site. Data will be collected using eight aircraft equipped with a variety of specialized sensors, four specially instrumented surface sites, and two prototype surface radar systems. The architecture of CLASIC includes a high-altitude surveillance aircraft and enhanced vertical thermodynamic and wind profile measurements that will characterize the synoptic scale structure of the clouds and the land surface within the ACRF SGP site. Mesoscale and microscale structures will be sampled with a variety of aircraft, surface, and radar observations. An overview of the measurement platforms that will be used during the CLASIC are described in this report. The coordination of measurements, especially as it relates to aircraft flight plans, will be discussed in the CLASIC Implementation Plan.

  9. Measuring Surface Combatant Fleet Effectiveness

    National Research Council Canada - National Science Library

    Crary, Michael

    1999-01-01

    ...? While Measures of Effectiveness for an individual ship can include its number of missiles, speed, and endurance, it is difficult to find a Measure of Effectiveness credible to experienced warplanners...

  10. Surface activity, lipid profiles and their implications in cervical cancer.

    Directory of Open Access Journals (Sweden)

    Preetha A

    2005-01-01

    Full Text Available Background: The profiles of lipids in normal and cancerous tissues may differ revealing information about cancer development and progression. Lipids being surface active, changes in lipid profiles can manifest as altered surface activity profiles. Langmuir monolayers offer a convenient model for evaluating surface activity of biological membranes. Aims: The aims of this study were to quantify phospholipids and their effects on surface activity of normal and cancerous human cervical tissues as well as to evaluate the role of phosphatidylcholine (PC and sphingomyelin (SM in cervical cancer using Langmuir monolayers. Methods and Materials: Lipid quantification was done using thin layer chromatography and phosphorus assay. Surface activity was evaluated using Langmuir monolayers. Monolayers were formed on the surface of deionized water by spreading tissue organic phase corresponding to 1 mg of tissue and studying their surface pressure-area isotherms at body temperature. The PC and SM contents of cancerous human cervical tissues were higher than those of the normal human cervical tissues. Role of PC and SM were evaluated by adding varying amounts of these lipids to normal cervical pooled organic phase. Statistical analysis: Student′s t-test (p < 0.05 and one-way analysis of variance (ANOVA was used. Results: Our results reveals that the phosphatidylglycerol level in cancerous cervical tissue was nearly five folds higher than that in normal cervical tissue. Also PC and sphingomyelin SM were found to be the major phospholipid components in cancerous and normal cervical tissues respectively. The addition of either 1.5 µg DPPC or 0.5 µg SM /mg of tissue to the normal organic phase changed its surface activity profile to that of the cancerous tissues. Statistically significant surface activity parameters showed that PC and SM have remarkable roles in shifting the normal cervical lipophilic surface activity towards that of cancerous lipophilic

  11. Optimization for sinusoidal profiles in surface relief gratings ...

    Indian Academy of Sciences (India)

    2014-02-07

    Feb 7, 2014 ... filometry [7–9] and monitoring of surface self-diffusion of solids under ultrahigh vacuum conditions [10]. In the present work, recording parameters, i.e. exposure time and deve- lopment time for fabrication of such holographic gratings have been optimized to obtain nearly perfect sinusoidal profiles in the ...

  12. Surface charge measurement by the Pockels effect

    CERN Document Server

    Sam, Y L

    2001-01-01

    have been observed by applying both impulse and AC voltages to a needle electrode in direct contact with the BSO. AC surface discharge behaviour of polymeric materials bonded to the BSO has also been investigated. The effect of the surrounding environment has been experimentally examined by placing the cell inside a vacuum chamber. Surface charge measurements have been made at various atmospheric pressures. The effect of an electro-negative gas (Sulphur Hexafluoride) on the surface charge distribution has also been investigated. This thesis is concerned with the design and development of a surface charge measurement system using Pockels effect. The measurement of surface charge is important in determining the electrical performance of high voltage insulation materials. The method proposed allows on-line measurement of charge and can generate two-dimensional images that represent the charge behaviour on the surface of the material under test. The measurement system is optical and uses a Pockels crystal as the ...

  13. MEASURING NEUTRON STAR RADII VIA PULSE PROFILE MODELING WITH NICER

    Energy Technology Data Exchange (ETDEWEB)

    Özel, Feryal; Psaltis, Dimitrios; Bauböck, Michi [Astronomy Department, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721 (United States); Arzoumanian, Zaven [Center for Research and Exploration in Space Science and Technology/USRA, NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States); Morsink, Sharon, E-mail: fozel@email.arizona.edu [Department of Physics, University of Alberta, 11455 Saskatchewan Drive, Edmonton, AB T6G 2E1 (Canada)

    2016-11-20

    The Neutron-star Interior Composition Explorer is an X-ray astrophysics payload that will be placed on the International Space Station . Its primary science goal is to measure with high accuracy the pulse profiles that arise from the non-uniform thermal surface emission of rotation-powered pulsars. Modeling general relativistic effects on the profiles will lead to measuring the radii of these neutron stars and to constraining their equation of state. Achieving this goal will depend, among other things, on accurate knowledge of the source, sky, and instrument backgrounds. We use here simple analytic estimates to quantify the level at which these backgrounds need to be known in order for the upcoming measurements to provide significant constraints on the properties of neutron stars. We show that, even in the minimal-information scenario, knowledge of the background at a few percent level for a background-to-source countrate ratio of 0.2 allows for a measurement of the neutron star compactness to better than 10% uncertainty for most of the parameter space. These constraints improve further when more realistic assumptions are made about the neutron star emission and spin, and when additional information about the source itself, such as its mass or distance, are incorporated.

  14. Laboratory measurements of dusty surface charging in plasma.

    Science.gov (United States)

    Chou, Kevin; Wang, Joseph

    2017-09-01

    A novel method is developed to study the charging of a conducting surface covered by a thin dust layer in plasma. The potential profile in the dust layer and the floating potential of the surface underneath are measured directly by embedding conducting wires in the dust and connecting the wires to a measurement plate outside the vacuum chamber, where a Trek non-contacting electrostatic voltmeter measures the floating potential of the measurement plate. Laboratory experiments are carried out to study plasma charging of a conducting plate covered by lunar dust simulant, JSC-1A. The results show that the plate potential is dependent on both the ambient plasma condition and the dust layer thickness. The current balance condition controls the floating potential of the dust surface while the dust layer acts as a capacitor and controls the potential of the plate with respect to the dust surface. Hence, a dust covered conducting plate will be charged more negatively than a clean plate.

  15. Partial compensation interferometry for measurement of surface parameter error of high-order aspheric surfaces

    Science.gov (United States)

    Hao, Qun; Li, Tengfei; Hu, Yao

    2018-01-01

    Surface parameters are the properties to describe the shape characters of aspheric surface, which mainly include vertex radius of curvature (VROC) and conic constant (CC). The VROC affects the basic properties, such as focal length of an aspheric surface, while the CC is the basis of classification for aspheric surface. The deviations of the two parameters are defined as surface parameter error (SPE). Precisely measuring SPE is critical for manufacturing and aligning aspheric surface. Generally, SPE of aspheric surface is measured directly by curvature fitting on the absolute profile measurement data from contact or non-contact testing. And most interferometry-based methods adopt null compensators or null computer-generated holograms to measure SPE. To our knowledge, there is no effective way to measure SPE of highorder aspheric surface with non-null interferometry. In this paper, based on the theory of slope asphericity and the best compensation distance (BCD) established in our previous work, we propose a SPE measurement method for high-order aspheric surface in partial compensation interferometry (PCI) system. In the procedure, firstly, we establish the system of two element equations by utilizing the SPE-caused BCD change and surface shape change. Then, we can simultaneously obtain the VROC error and CC error in PCI system by solving the equations. Simulations are made to verify the method, and the results show a high relative accuracy.

  16. NEW CONCEPTS AND TEST METHODS OF CURVE PROFILE AREA DENSITY IN SURFACE: ESTIMATION OF AREAL DENSITY ON CURVED SPATIAL SURFACE

    OpenAIRE

    Hong Shen

    2011-01-01

    The concepts of curve profile, curve intercept, curve intercept density, curve profile area density, intersection density in containing intersection (or intersection density relied on intersection reference), curve profile intersection density in surface (or curve intercept intersection density relied on intersection of containing curve), and curve profile area density in surface (AS) were defined. AS expressed the amount of curve profile area of Y phase in the unit containing surface area, S...

  17. Contact area measurements on structured surfaces

    DEFF Research Database (Denmark)

    Kücükyildiz, Ömer Can; Jensen, Sebastian Hoppe Nesgaard; De Chiffre, Leonardo

    In connection with the use of brass specimens featuring structured surfaces in a tribology test, an algorithm was developed for automatic measurement of the contact area by optical means.......In connection with the use of brass specimens featuring structured surfaces in a tribology test, an algorithm was developed for automatic measurement of the contact area by optical means....

  18. Fatty acid methyl ester profiles of bat wing surface lipids.

    Science.gov (United States)

    Pannkuk, Evan L; Fuller, Nathan W; Moore, Patrick R; Gilmore, David F; Savary, Brett J; Risch, Thomas S

    2014-11-01

    Sebocytes are specialized epithelial cells that rupture to secrete sebaceous lipids (sebum) across the mammalian integument. Sebum protects the integument from UV radiation, and maintains host microbial communities among other functions. Native glandular sebum is composed primarily of triacylglycerides (TAG) and wax esters (WE). Upon secretion (mature sebum), these lipids combine with minor cellular membrane components comprising total surface lipids. TAG and WE are further cleaved to smaller molecules through oxidation or host enzymatic digestion, resulting in a complex mixture of glycerolipids (e.g., TAG), sterols, unesterified fatty acids (FFA), WE, cholesteryl esters, and squalene comprising surface lipid. We are interested if fatty acid methyl ester (FAME) profiling of bat surface lipid could predict species specificity to the cutaneous fungal disease, white nose syndrome (WNS). We collected sebaceous secretions from 13 bat spp. using Sebutape(®) and converted them to FAME with an acid catalyzed transesterification. We found that Sebutape(®) adhesive patches removed ~6× more total lipid than Sebutape(®) indicator strips. Juvenile eastern red bats (Lasiurus borealis) had significantly higher 18:1 than adults, but 14:0, 16:1, and 20:0 were higher in adults. FAME profiles among several bat species were similar. We concluded that bat surface lipid FAME profiling does not provide a robust model predicting species susceptibility to WNS. However, these results provide baseline data that can be used for lipid roles in future ecological studies, such as life history, diet, or migration.

  19. Temperature profiles on the gadolinium surface during electron beam evaporation

    International Nuclear Information System (INIS)

    Ohba, Hironori; Shibata, Takemasa

    1995-01-01

    The distributions of surface temperature of gadolinium in a water-cooled copper crucible during electron beam evaporation were measured by optical pyrometry. The surface temperatures were obtained from the radiation intensity ratio of the evaporating surface and a reference light source using Planck's law of radiation. The emitted radiation from the evaporating surface and a reference source was detected by a CCD sensor through a band pass filter of 650 nm. The measured surface temperature generally agreed with those estimated from the deposition rate and the data of the saturated vapor pressure. At high input powers, it was found that the measured value had small difference with the estimated one due to variation of the surface condition. (author)

  20. A novel non-contact profiler design for measuring synchrotron radiation mirrors

    International Nuclear Information System (INIS)

    Lin, Yao; Takacs, P.Z.; Furenlid, K.; DeBiasse, R.A.; Wang, Run-Wen

    1990-08-01

    A novel optical profiler is described in this paper for measurement of surface profiles of synchrotron radiation (SR) mirrors. The measurement is based on a combination of an optical heterodyne technique and a precise phase measurement procedure without a reference surface. A Zeeman two-frequency He-Ne laser is employed as the light source. The common-path optical system, which uses a birefringent lens as the beam splitter, minimizes the effects of air turbulence, sample vibration and temperature variation. A special autofocus system allows the profiler to measure the roughness and shape of a sample surface. The optical system is mounted on a large linear air-bearing slide, and is capable of scanning over distances covering the spatial period range from several microns to nearly one meter with a high measurement accuracy. 9 refs., 5 figs

  1. Study on error analysis and accuracy improvement for aspheric profile measurement

    Science.gov (United States)

    Gao, Huimin; Zhang, Xiaodong; Fang, Fengzhou

    2017-06-01

    Aspheric surfaces are important to the optical systems and need high precision surface metrology. Stylus profilometry is currently the most common approach to measure axially symmetric elements. However, if the asphere has the rotational alignment errors, the wrong cresting point would be located deducing the significantly incorrect surface errors. This paper studied the simulated results of an asphere with rotational angles around X-axis and Y-axis, and the stylus tip shift in X, Y and Z direction. Experimental results show that the same absolute value of rotational errors around X-axis would cause the same profile errors and different value of rotational errors around Y-axis would cause profile errors with different title angle. Moreover, the greater the rotational errors, the bigger the peak-to-valley value of profile errors. To identify the rotational angles in X-axis and Y-axis, the algorithms are performed to analyze the X-axis and Y-axis rotational angles respectively. Then the actual profile errors with multiple profile measurement around X-axis are calculated according to the proposed analysis flow chart. The aim of the multiple measurements strategy is to achieve the zero position of X-axis rotational errors. Finally, experimental results prove the proposed algorithms achieve accurate profile errors for aspheric surfaces avoiding both X-axis and Y-axis rotational errors. Finally, a measurement strategy for aspheric surface is presented systematically.

  2. Surface texture measurement for dental wear applications

    Science.gov (United States)

    Austin, R. S.; Mullen, F.; Bartlett, D. W.

    2015-06-01

    The application of surface topography measurement and characterization within dental materials science is highly active and rapidly developing, in line with many modern industries. Surface measurement and structuring is used extensively within oral and dental science to optimize the optical, tribological and biological performance of natural and biomimetic dental materials. Although there has historically been little standardization in the use and reporting of surface metrology instrumentation and software, the dental industry is beginning to adopt modern areal measurement and characterization techniques, especially as the dental industry is increasingly adopting digital impressioning techniques in order to leverage CAD/CAM technologies for the design and construction of dental restorations. As dental treatment becomes increasingly digitized and reliant on advanced technologies such as dental implants, wider adoption of standardized surface topography and characterization techniques will become evermore essential. The dental research community welcomes the advances that are being made in surface topography measurement science towards realizing this ultimate goal.

  3. Technique for measuring very high surface velocities

    International Nuclear Information System (INIS)

    Maron, Y.

    1977-01-01

    An interferometric technique for measuring displacements of surfaces moving at velocities in the range of a few millimeters per microsecond is presented. The Doppler shift of frequency of light scattered from such surfaces is too high to be detectable by known devices. The present technique is based upon monitoring the signal resulting from the interference between two beams reflected from the surface at different incidence angles. Measurement systems for specularly as well as diffusely reflecting surfaces are described. Light source with very modest temporal coherence delivering about 100 mw power is required. The accuracy of the technique is discussed. (author)

  4. Constructing invariant fairness measures for surfaces

    DEFF Research Database (Denmark)

    Gravesen, Jens; Ungstrup, Michael

    2002-01-01

    The paper proposes a rational method to derive fairness measures for surfaces. It works in cases where isophotes, reflection lines, planar intersection curves, or other curves are used to judge the fairness of the surface. The surface fairness measure is derived by demanding that all the given cu...... of curves. Six basic third order invariants by which the fairing measures can be expressed are defined. Furthermore, the geometry of a plane intersection curve is studied, and the variation of the total, the normal, and the geodesic curvature and the geodesic torsion is determined....

  5. Surface tension measurements with a smartphone

    Science.gov (United States)

    Goy, Nicolas-Alexandre; Denis, Zakari; Lavaud, Maxime; Grolleau, Adrian; Dufour, Nicolas; Deblais, Antoine; Delabre, Ulysse

    2017-11-01

    Smartphones are increasingly used in higher education and at university in mechanics, acoustics, and even thermodynamics as they offer a unique way to do simple science experiments. In this article, we show how smartphones can be used in fluid mechanics to measure surface tension of various liquids, which could help students understand the concept of surface tension through simple experiments.

  6. Constructing Invariant Fairness Measures for Surfaces

    DEFF Research Database (Denmark)

    Gravesen, Jens; Ungstrup, Michael

    1998-01-01

    This paper presents a general method which from an invariant curve fairness measure constructs an invariant surface fairness measure. Besides the curve fairness measure one only needs a class of curves on the surface for which one wants to apply the curve measure. The surface measure at a point...... variation.The method is extended to the case where one considers, not the fairness of one curve, but the fairness of a one parameter family of curves. Such a family is generated by the flow of a vector field, orthogonal to the curves. The first, respectively the second order derivative along the curve...... of the size of this vector field is used as the fairness measure on the family.Six basic 3rd order invariants satisfying two quadratic equations are defined. They form a complete set in the sense that any invariant 3rd order function can be written as a function of the six basic invariants together...

  7. Preparation of stable silica surfaces for surface forces measurement

    Science.gov (United States)

    Ren, Huai-Yin; Mizukami, Masashi; Kurihara, Kazue

    2017-09-01

    A surface forces apparatus (SFA) measures the forces between two surfaces as a function of the surface separation distance. It is regarded as an essential tool for studying the interactions between two surfaces. However, sample surfaces used for the conventional SFA measurements have been mostly limited to thin (ca. 2-3 μm) micas, which are coated with silver layers (ca. 50 nm) on their back, due to the requirement of the distance determination by transmission mode optical interferometry called FECO (fringes of equal chromatic order). The FECO method has the advantage of determining the absolute distance, so it should be important to increase the availability of samples other than mica, which is chemically nonreactive and also requires significant efforts for cleaving. Recently, silica sheets have been occasionally used in place of mica, which increases the possibility of surface modification. However, in this case, the silver layer side of the sheet is glued on a cylindrical quartz disc using epoxy resin, which is not stable in organic solvents and can be easily swollen or dissolved. The preparation of substrates more stable under severe conditions, such as in organic solvents, is necessary for extending application of the measurement. In this study, we report an easy method for preparing stable silica layers of ca. 2 μm in thickness deposited on gold layers (41 nm)/silica discs by sputtering, then annealed to enhance the stability. The obtained silica layers were stable and showed no swelling in organic solvents such as ethanol and toluene.

  8. Characterization of a traceable profiler instrument for areal roughness measurement

    International Nuclear Information System (INIS)

    Thomsen-Schmidt, P

    2011-01-01

    A two-dimensional profiler instrument was designed and realized at the PTB (Physikalisch-Technische Bundesanstalt). The main function of the instrument is to provide traceable results in the field of roughness measurement. It is equipped with a linear moving stylus which is guided by precision air bearings. The moving part of the stylus has weight around 1 g and is carried by a magnetic field. The contacting force of the tip onto the surface under test is controlled by a small voice coil actuator in a closed control loop. Vertical movements of the stylus are captured by two different, completely independent measurement systems, covering a range of 100 µm. The first one is an interferometer, which provides a traceable signal, and the second one is an inductive measurement system. The signal from the inductive measurement system is calibrated by the interferometer. The sample under test is carried within the x–y-plane by a linear guided table with low noise air bearings. These air bearings are preloaded by vacuum and a constant gap is achieved by gas pressure controllers. Both axes of the table are driven by linear voice coil actuators and their movement in the plane is measured by linear encoders. The sample carrier is equipped with two axes tilt compensation, by which the sample under test can be levelled automatically using the measurement system of the stylus. Real-time data acquisition, manual handling and automated procedures are managed by a programmable controller and proprietary software written in LabVIEW. After measurement, data from the system can be directly transferred into the smd- or sdf-format. Results of measurements on different samples to characterize the metrological behaviour of the instrument will be reported. To characterize the uncertainty of the instrument, a model is applied, which is in accordance with approved rules for contact stylus instruments

  9. IceBridge UAF Lidar Profiler L1B Geolocated Surface Elevation Triplets

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA IceBridge UAF Lidar Profiler L1B Geolocated Surface Elevation Triplets data set contains surface profiles of Alaska Glaciers acquired using the airborne...

  10. Neutral Probe Beam q-profile measurements in PDX and PBX-M

    International Nuclear Information System (INIS)

    Kugel, H.W.; Gammel, G.M.; Kaita, R.; Reusch, M.F.; Roberts, D.W.

    1988-06-01

    Using the Fast Ion Diagnostic Experiment (FIDE) technique, a Neutral Probe Beam (NPB) can be aimed to inject tangentially to a magnetic surface. The resultant ion orbit shifts, due to conservation of canonical toroidal angular momentum, can be measured with a multi-sightline charge-exchange analyzer to yield direct measurements of radial magnetic flux profiles, current density profiles, the radial position of the magnetic axis, flux surface inner and outer edges, q-profiles, and central-q time dependencies. An extensive error analysis was performed on previous PDX q-measurements in circular plasmas and the resulting estimated contributions of various systematic effects are discussed. Preliminary results of fast ion orbit shift measurements at early times in indented PBX-M plasmas are given. Methods for increasing the absolute experimental precision of similar measurements in progress on PBX-M are discussed. 4 refs., 3 figs

  11. Space potential, temperature, and density profile measurements on RENTOR

    International Nuclear Information System (INIS)

    Schoch, P.M.

    1983-05-01

    Radial profiles of the space potential, electron temperature, and density have been measured on RENTOR with a heavy-ion-beam probe. The potential profile has been compared to predictions from a stochastic magnetic field fluctuation theory, using the measured temperature and density profiles. The comparison shows strong qualitative agreement in that the potential is positive and the order of T/sub e//e. There is some quantitative disagreement in that the measured radial electric fields are somewhat smaller than the theoretical predictions. To facilitate this comparison, a detailed analysis of the possible errors has been completed

  12. Chloride ingress profiles measured by electron probe micro analysis

    DEFF Research Database (Denmark)

    Jensen, Ole mejlhede; Coats, Alison M.; Glasser, Fred P.

    1996-01-01

    Traditional techniques for measuring chloride ingress profiles do not apply well to high performance cement paste systems; the geometric resolution of the traditional measuring techniques is too low. In this paper measurements by Electron Probe Micro Analysis (EPMA) are presented. EPMA is demonst......Traditional techniques for measuring chloride ingress profiles do not apply well to high performance cement paste systems; the geometric resolution of the traditional measuring techniques is too low. In this paper measurements by Electron Probe Micro Analysis (EPMA) are presented. EPMA...

  13. The GALEX/S4G Surface Brightness and Color Profiles Catalog. I. Surface Photometry and Color Gradients of Galaxies

    Science.gov (United States)

    Bouquin, Alexandre Y. K.; Gil de Paz, Armando; Muñoz-Mateos, Juan Carlos; Boissier, Samuel; Sheth, Kartik; Zaritsky, Dennis; Peletier, Reynier F.; Knapen, Johan H.; Gallego, Jesús

    2018-02-01

    We present new spatially resolved surface photometry in the far-ultraviolet (FUV) and near-ultraviolet (NUV) from images obtained by the Galaxy Evolution Explorer (GALEX) and IRAC1 (3.6 μm) photometry from the Spitzer Survey of Stellar Structure in Galaxies (S4G). We analyze the radial surface brightness profiles μ FUV, μ NUV, and μ [3.6], as well as the radial profiles of (FUV ‑ NUV), (NUV ‑ [3.6]), and (FUV ‑ [3.6]) colors in 1931 nearby galaxies (z measured scale length and central surface brightness values yield distributions of spin and circular velocity within a factor of two of those obtained via direct kinematic measurements. We find that at a surface brightness fainter than μ [3.6] = 20.89 mag arcsec‑2, or below 3 × 108 M ⊙ kpc‑2 in stellar mass surface density, the average specific star formation rate (sSFR) for star-forming and quiescent galaxies remains relatively flat with radius. However, a large fraction of GALEX Green Valley galaxies show a radial decrease in sSFR. This behavior suggests that an outside-in damping mechanism, possibly related to environmental effects, could be testimony of an early evolution of galaxies from the blue sequence of star-forming galaxies toward the red sequence of quiescent galaxies.

  14. Surface Roughness Measurement on a Wing Aircraft by Speckle Correlation

    Directory of Open Access Journals (Sweden)

    Alberto Barrientos

    2013-09-01

    Full Text Available The study of the damage of aeronautical materials is important because it may change the microscopic surface structure profiles. The modification of geometrical surface properties can cause small instabilities and then a displacement of the boundary layer. One of the irregularities we can often find is surface roughness. Due to an increase of roughness and other effects, there may be extra momentum losses in the boundary layer and a modification in the parasite drag. In this paper we present a speckle method for measuring the surface roughness on an actual unmanned aircraft wing. The results show an inhomogeneous roughness distribution on the wing, as expected according to the anisotropic influence of the winds over the entire wing geometry. A calculation of the uncertainty of the technique is given.

  15. Surface roughness measurement on a wing aircraft by speckle correlation.

    Science.gov (United States)

    Salazar, Félix; Barrientos, Alberto

    2013-09-05

    The study of the damage of aeronautical materials is important because it may change the microscopic surface structure profiles. The modification of geometrical surface properties can cause small instabilities and then a displacement of the boundary layer. One of the irregularities we can often find is surface roughness. Due to an increase of roughness and other effects, there may be extra momentum losses in the boundary layer and a modification in the parasite drag. In this paper we present a speckle method for measuring the surface roughness on an actual unmanned aircraft wing. The results show an inhomogeneous roughness distribution on the wing, as expected according to the anisotropic influence of the winds over the entire wing geometry. A calculation of the uncertainty of the technique is given.

  16. Measurement of Gas-Surface Accommodation

    Science.gov (United States)

    Trott, W. M.; Rader, D. J.; Castañeda, J. N.; Torczynski, J. R.; Gallis, M. A.

    2008-12-01

    Thermal accommodation coefficients have been determined for a variety of gas-surface combinations using an experimental apparatus developed to measure both the pressure dependence of the conductive heat flux and the variation of gas density between parallel plates separated by a gas-filled gap. Effects of gas composition, surface roughness and surface contamination have been examined with this system, and the behavior of gas mixtures has also been explored. Results are discussed in comparison with previous parallel-plate experimental studies as well as numerical simulations.

  17. Removal of Surface-Reflected Light for the Measurement of Remote-Sensing Reflectance from an Above-Surface Platform

    Science.gov (United States)

    2010-12-06

    REPORT DATE IDD-MM- YYYY) 14-02-2011 2. REPORT TYPE Journal Article 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Removal of Surface...impossible to obtain Rr, from measurements of vertical profiles of Lu and Elt [6]. During the experiment, the surface was calm [see Fig. 8(a)] and

  18. Lidar measured vertical atmospheric scattering profiles

    NARCIS (Netherlands)

    Kunz, G.J.

    1985-01-01

    The vertical structure of the atmosphere, which is of invaluable interest to meteorologists, geo-physicists and environmental researchers, can be measured with LIDAR. A method has been proposed and applied to invert lidar signals from vertical soundings to height resolved scattering coefficients. In

  19. Application of an Ecological Surface Treatment for Aluminum Profile

    Directory of Open Access Journals (Sweden)

    Brenda Luisa McNeil-Montañes

    2015-11-01

    Full Text Available Once aluminium is extruded, in contact with oxygen, forms quickly an aluminium oxide superficial protector layer, which is not penetrated  by humidity, gases or polluting agents. This layer has a low thickness and is a bad base for painting anchorage. Through the chemical superficial treatment of the aluminium profile (degreased, deoxidized and cleaning, it is possible its preparation to el iminate the thin oxide superficial layer and dirty and to form a layer of better features. This process is carried out submerging the profiles in the sour dissolution and in the cleaning dissolution (water from the aqueduct and also treated water, without  ions to leave them clean and lastly it is carried out the surface passivation treatment, also called chemical conversion treatment, to obtain bigger penetration and stability of the paintings. The lacquered plant of aluminium, Lacalum, which is the only o ne of this type in the country, used to employ and old technology of chemical superficial treatment using watery solutions that contained hexavalents chromium ions, in order to form a protector layer on the aluminium profiles. This chemical treatment is very harmful to health, that why it was decided its substitution for a new advanced and respectful with the environment technology of non-chromium treatment; as well as the installation of a treatment plant for the process residuals. In general, these improv ements allow obtaining a better product with the smallest impact to the environment as possible, and better in social aspect, thanks to the humanization of the work, and also in economic aspect, because of the decrease of the production costs. In this work, specifications, that most be considered during this non -chromium superficial chemical treatment of the aluminium profiles, are given to obtain a later lacquered; as well as the improvements for the environment.

  20. A measurement system for vertical seawater profiles close to the air-sea interface

    Science.gov (United States)

    Sims, Richard P.; Schuster, Ute; Watson, Andrew J.; Yang, Ming Xi; Hopkins, Frances E.; Stephens, John; Bell, Thomas G.

    2017-09-01

    This paper describes a near-surface ocean profiler, which has been designed to precisely measure vertical gradients in the top 10 m of the ocean. Variations in the depth of seawater collection are minimized when using the profiler compared to conventional CTD/rosette deployments. The profiler consists of a remotely operated winch mounted on a tethered yet free-floating buoy, which is used to raise and lower a small frame housing sensors and inlet tubing. Seawater at the inlet depth is pumped back to the ship for analysis. The profiler can be used to make continuous vertical profiles or to target a series of discrete depths. The profiler has been successfully deployed during wind speeds up to 10 m s-1 and significant wave heights up to 2 m. We demonstrate the potential of the profiler by presenting measured vertical profiles of the trace gases carbon dioxide and dimethylsulfide. Trace gas measurements use an efficient microporous membrane equilibrator to minimize the system response time. The example profiles show vertical gradients in the upper 5 m for temperature, carbon dioxide and dimethylsulfide of 0.15 °C, 4 µatm and 0.4 nM respectively.

  1. A measurement system for vertical seawater profiles close to the air–sea interface

    Directory of Open Access Journals (Sweden)

    R. P. Sims

    2017-09-01

    Full Text Available This paper describes a near-surface ocean profiler, which has been designed to precisely measure vertical gradients in the top 10 m of the ocean. Variations in the depth of seawater collection are minimized when using the profiler compared to conventional CTD/rosette deployments. The profiler consists of a remotely operated winch mounted on a tethered yet free-floating buoy, which is used to raise and lower a small frame housing sensors and inlet tubing. Seawater at the inlet depth is pumped back to the ship for analysis. The profiler can be used to make continuous vertical profiles or to target a series of discrete depths. The profiler has been successfully deployed during wind speeds up to 10 m s−1 and significant wave heights up to 2 m. We demonstrate the potential of the profiler by presenting measured vertical profiles of the trace gases carbon dioxide and dimethylsulfide. Trace gas measurements use an efficient microporous membrane equilibrator to minimize the system response time. The example profiles show vertical gradients in the upper 5 m for temperature, carbon dioxide and dimethylsulfide of 0.15 °C, 4 µatm and 0.4 nM respectively.

  2. Interpreting the probe-surface interaction of surface measuring instruments, or what is a surface?

    Science.gov (United States)

    Leach, Richard; Weckenmann, Albert; Coupland, Jeremy; Hartmann, Wito

    2014-09-01

    When using dimensional measuring instruments it is assumed that there is a property of the object, which we call surface, that is present before during and after the measurement, i.e. the surface is a fundamental property of an object that can, by appropriate means, be used to measure geometry. This paper will attempt to show that the fundamental property ‘surface’ does not exist in any simple form and that all the information we can have about a surface is the measurement data, which will include measurement uncertainty. Measurement data, or what will be referred to as the measured surface, is all that really exists. In this paper the basic physical differences between mechanically, electromagnetically and electrically measured surfaces are highlighted and discussed and accompanied by measurement results on a roughness artefact.

  3. Interpreting the probe-surface interaction of surface measuring instruments, or what is a surface?

    International Nuclear Information System (INIS)

    Leach, Richard; Weckenmann, Albert; Hartmann, Wito; Coupland, Jeremy

    2014-01-01

    When using dimensional measuring instruments it is assumed that there is a property of the object, which we call surface, that is present before during and after the measurement, i.e. the surface is a fundamental property of an object that can, by appropriate means, be used to measure geometry. This paper will attempt to show that the fundamental property ‘surface’ does not exist in any simple form and that all the information we can have about a surface is the measurement data, which will include measurement uncertainty. Measurement data, or what will be referred to as the measured surface, is all that really exists. In this paper the basic physical differences between mechanically, electromagnetically and electrically measured surfaces are highlighted and discussed and accompanied by measurement results on a roughness artefact. (paper)

  4. Aeolian vertical mass flux profiles above dry and moist sandy beach surfaces

    Science.gov (United States)

    Rotnicka, Joanna

    2013-04-01

    The vertical distribution of aeolian mass flux was investigated in a natural beach environment. Field experiments conducted on the beach of the Łeba Barrier, southern Baltic coast, Poland, measured the sand transport rate and the vertical mass flux distribution above dry rippled sand and a moist flat sandy surface. The experiments were intended to show the changes in the vertical distribution of sand with changing wind speed. All the data represent saturated flux conditions. Sand transport was measured using 0.5 m-high vertically segmented passive sand traps, while the wind speed and direction were monitored at 1 m elevation. The obtained dataset comprises 65 measurements on dry surfaces and 51 measurements on moist sandy surfaces. The sand transport rate above the moist surface was up to 90% higher than above the dry surface for wind speeds of 7-11 m/s, but higher velocities gave smaller differences between the surfaces. The saltation layer was thicker above the moist surface than above the dry surface. All the vertical sand flux profiles are best described by exponential decay functions. Analysis of the normalised flux profiles grouped by wind velocity shows that the fitted curves are less inclined for moist surfaces than dry surfaces. Moreover, the regression coefficients depict a marked trend in which the intercept decreases and the slope increases with increasing wind speed; this indicates that more sand is transported at higher elevations above the bed and less at lower elevations. The proportion of total transport seems to be independent of wind speed at elevations of approximately 35 mm and 50 mm above the dry and moist surfaces, respectively. Differences between the measured- and exponential-fit values of mass flux are particularly distinct close to the bed, where the exponential fit either over- or under-predicts the measured values. Over-predictions occur in weaker winds (up to 6-7 m/s), whereas under-predictions become more pronounced as the wind

  5. Surface resistivity measurement of plasma treated polymers

    International Nuclear Information System (INIS)

    Simon, D.; Pigram, P.J.; Liesegang, J.

    2000-01-01

    Full text: Resistivity of insulators is an important property of materials used within the integrated circuit and packaging industries. The measurement of electrical resistivity of insulator materials in the surface region in this work is interpreted through observations of surface charge decay. A self-field driven and diffusion charge transport theory is used to model the process and resistivity values obtained computationally. Data for the charge decay of surface charged samples are collected by suspending them inside a coaxial cylinder connected to an electrometer. Samples used have been low density polyethylene LDPE sheet, both pristine and surface treated. Some samples have been treated by air plasma at low vacuum pressures for different periods of time; others have been washed in ethyl acetate and then plasma treated before the resistivity measurement. The sets of resistivity measurements form the various treatments are compared below. X-ray photoelectron spectroscopy (XPS) has also been used to investigate and account for the observed variations in surface resistivity

  6. Optical triangulation method for height measurements on water surfaces

    Science.gov (United States)

    Maas, Hans-Gerd; Hentschel, Bernd; Schreiber, Frank

    2003-01-01

    Optical triangulation methods based on a laser light sheet and a camera are frequently used as a surface measurement technique in a wide range of applications. They allow for the fast accurate determination of height profiles, based on relatively simple hardware and software configurations. Moreover, they can be implemented very efficiently and are especially suited for measurements on moving objects such as products on an assembly line. The study presented in the paper describes the adaptation of laser light sheet optical triangulation techniques to the task of water level profile measurements in hydromechanics experimental facilities. The properties of water surfaces necessitate several modifications of optical triangulation techniques to make them applicable: The mirror-like reflection properties of water surfaces form a contradiction to the assumption of diffuse reflection, on which standard light sheet triangulation techniques are based; this problem can be circumvented by using a diffuse reflecting projection plane to capture the mirror-like reflection of the laser line from the water surface. Due to the angle of incidence law, however, water surface tilts caused by waves will usually cause a strong degradation of the quality of the results when using reflected light; this effect can largely be compensated by processing max-store images derived from short image sequences rather than single images. These extensions of optical triangulation turned out to be crucial for the applicability of the method on water surfaces. Besides the theoretical concept and a sensitivity analysis of the method, a system configuration is outlined, and the results of a number of practical experiments are shown and discussed.

  7. Surface Tension Measurements with a Smartphone

    Science.gov (United States)

    Goy, Nicolas-Alexandre; Denis, Zakari; Lavaud, Maxime; Grolleau, Adrian; Dufour, Nicolas; Deblais, Antoine; Delabre, Ulysse

    2017-01-01

    Smartphones are increasingly used in higher education and at university in mechanics, acoustics, and even thermodynamics as they offer a unique way to do simple science experiments. In this article, we show how smartphones can be used in fluid mechanics to measure surface tension of various liquids, which could help students understand the concept…

  8. Surface charge measurement using an electrostatic probe

    DEFF Research Database (Denmark)

    Crichton, George C; McAllister, Iain Wilson

    1998-01-01

    During the 1960s, the first measurements of charge on dielectric surfaces using simple electrostatic probes were reported. However it is only within the last 10 years that a proper understanding of the probe response has been developed. This situation arose as a consequence of the earlier studies...

  9. Optical measurement of surface roughness in manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Brodmann, R.

    1984-11-01

    The measuring system described here is based on the light-scattering method, and was developed by Optische Werke G. Rodenstock, Munich. It is especially useful for rapid non-contact monitoring of surface roughness in production-related areas. This paper outlines the differences between this system and the common stylus instrument, including descriptions of some applications in industry.

  10. SURFACE BRIGHTNESS PROFILES OF DWARF GALAXIES. II. COLOR TRENDS AND MASS PROFILES

    Energy Technology Data Exchange (ETDEWEB)

    Herrmann, Kimberly A. [Penn State Mont Alto, 1 Campus Drive, Mont Alto, PA 17237 (United States); Hunter, Deidre A. [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States); Elmegreen, Bruce G., E-mail: kah259@psu.edu, E-mail: dah@lowell.edu, E-mail: bge@us.ibm.com [IBM T. J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, NY 10598 (United States)

    2016-06-01

    In this second paper of a series, we explore the B  −  V , U  −  B , and FUV−NUV radial color trends from a multi-wavelength sample of 141 dwarf disk galaxies. Like spirals, dwarf galaxies have three types of radial surface brightness profiles: (I) single exponential throughout the observed extent (the minority), (II) down-bending (the majority), and (III) up-bending. We find that the colors of (1) Type I dwarfs generally become redder with increasing radius, unlike spirals which have a blueing trend that flattens beyond ∼1.5 disk scale lengths, (2) Type II dwarfs come in six different “flavors,” one of which mimics the “U” shape of spirals, and (3) Type III dwarfs have a stretched “S” shape where the central colors are flattish, become steeply redder toward the surface brightness break, then remain roughly constant beyond, which is similar to spiral Type III color profiles, but without the central outward bluing. Faint (−9 >  M{sub B}  > −14) Type II dwarfs tend to have continuously red or “U” shaped colors and steeper color slopes than bright (−14 >  M{sub B}  > −19) Type II dwarfs, which additionally have colors that become bluer or remain constant with increasing radius. Sm dwarfs and BCDs tend to have at least some blue and red radial color trend, respectively. Additionally, we determine stellar surface mass density (Σ) profiles and use them to show that the break in Σ generally remains in Type II dwarfs (unlike Type II spirals) but generally disappears in Type III dwarfs (unlike Type III spirals). Moreover, the break in Σ is strong, intermediate, and weak in faint dwarfs, bright dwarfs, and spirals, respectively, indicating that Σ may straighten with increasing galaxy mass. Finally, the average stellar surface mass density at the surface brightness break is roughly 1−2  M {sub ⊙} pc{sup −2} for Type II dwarfs but higher at 5.9  M {sub ⊙} pc{sup −2} or 27  M {sub ⊙} pc{sup −2} for

  11. Combining microwave radiometer and wind profiler radar measurements to improve accuracy and resolution of atmospheric humidity profiling

    Science.gov (United States)

    Bianco, L.; Cimini, D.; Ware, R.; Marzano, F.

    2003-04-01

    An algorithm to compute high-resolution atmospheric humidity profiling by synergetic use of microwave radiometer and wind profiler radar is illustrated. Wind profiler radar data are input for the computation of the potential refractivity gradient profiles, and combined with radiometer estimates of temperature profiles, which are needed to fully retrieve humidity gradient profiles. The algorithm makes use of recent developments in Wind Profiler Radar (WPR) signal processing, computing the zeroth, first, and second moments of WPR Doppler spectra via a fuzzy logic method (Bianco and Wilczak, 2002), which provides quality control of radar data in the spectral domain. The zeroth, first, and second moments are employed to compute the structure parameter of potential refractivity (C_φ^2), the horizontal wind (V_h), and the structure parameter of vertical velocity (C_w^2) respectively (Stankov et al. 2002). In addition, the algorithm uses a formula proposed by White (White et al. 1999) for the computation of C_w^2, to account for the spatial and temporal filtering effects on the Doppler spectrum. C_φ^2, V_h, and C_w^2 are then combined together to retrieve the potential refractivity gradient profiles. On the radiometric side, a first attempt is made using low resolution temperature profile estimates obtained following the algorithm described by Han and Westwater (1995), which make use of ground-based sensors, including a dual channel microwave radiometer (MWR), and other surface meteorological instruments. Then, the advantages of using estimates of temperature and humidity profiles from a multichannel microwave radiometer profiler (MWRP) are evaluated. Finally, the combined algorithm performances in retrieving humidity profiles are tested with simultaneous radiosonde "in situ" measurements. The empirical sets of WPR and MWR data were provided by the Atmospheric Radiation Measurement (ARM) Program, and collected at the ARM Southern Great Plains (SGP) site (latitude: 36^o

  12. Surface dose extrapolation measurements with radiographic film

    International Nuclear Information System (INIS)

    Butson, Martin J; Cheung Tsang; Yu, Peter K N; Currie, Michael

    2004-01-01

    Assessment of surface dose delivered from radiotherapy x-ray beams for optimal results should be performed both inside and outside the prescribed treatment fields. An extrapolation technique can be used with radiographic film to perform surface dose assessment for open field high energy x-ray beams. This can produce an accurate two-dimensional map of surface dose if required. Results have shown that the surface percentage dose can be estimated within ±3% of parallel plate ionization chamber results with radiographic film using a series of film layers to produce an extrapolated result. Extrapolated percentage dose assessment for 10 cm, 20 cm and 30 cm square fields was estimated to be 15% ± 2%, 29% ± 3% and 38% ± 3% at the central axis and relatively uniform across the treatment field. The corresponding parallel plate ionization chamber measurements are 16%, 27% and 37%, respectively. Surface doses are also measured outside the treatment field which are mainly due to scattered electron contamination. To achieve this result, film calibration curves must be irradiated to similar x-ray field sizes as the experimental film to minimize quantitative variations in film optical density caused by varying x-ray spectrum with field size. (note)

  13. Novel surface measurement system reading cost savings

    Energy Technology Data Exchange (ETDEWEB)

    Sword, M.

    1996-05-01

    A new state-of-the-art data acquisition system for the oil and natural gas industries is being marketed by OPSCO`92 Industries Ltd. The unit is portable, it measures surface data which is calibrated to bottom-hole conditions and designed to measure temperature and pressure information without the necessity of sending testing equipment downhole. The Surface Data System (SDS) uses silicon-crystal technology, is mounted in a suitcase size carrying case, and runs off a 12-volt battery enclosure which can be backed up by a small solar panel. The first generation system can handle 16 different channels of information input on a laptop computer. Pressure, pressure differential, temperature, frequency and pulse signals for flow meter measurements are handled by standard sensors. Areas of application include build-up and fall-off tests, pipeline evaluation, pre-frac tests, underbalanced drilling and gas well evaluation. 1 fig., 1 photo.

  14. Lower atmospheric temperature profile measurements using a Raman lidar

    Science.gov (United States)

    Melfi, S. H.; Whiteman, D.

    1986-01-01

    A Raman lidar system was used to measure the temperature profile of the upper troposphere and lower stratosphere. The system consists of a tripled Nd-YAG laser and a 1.5 meter diameter telescope. Two photomultipliers are used at the output of the telescope to allow for measurements at both the laser wavelength and at the Raman shifted wavelength due to atmospheric nitrogen. The signal from the photomultipliers is recorded as photon counts in 1 microsec bins. The results of a number of laser shots are summed together to provide atmospheric returns which have acceptable signal to noise characteristics. Measurements of the Raman nitrogen return were acquired up to an altitude in excess of 20 km. Temperature profiles were retrieved from the attenuation corrected Raman nitrogen return assuming the atmosphere to be in hydrostatic equilibrium and using the ideal gas law. Retrieved temperature profiles are shown compared with independent temperature measurements.

  15. Acoustic temperature profile measurement technique for large combustion chambers

    Science.gov (United States)

    Venkateshan, S. P.; Shakkottai, P.; Kwack, E. Y.; Back, L. H.

    1989-01-01

    Measurement of times of flight of sound waves can be used to determine temperatures in a gas. This paper describes a system, based on this principle, that is capable of giving the temperature profile in a nonisothermal gas volume, for example, prevalent in a large furnace. The apparatus is simple, rugged, accurate, and capable of being automated for process control applications. It is basically an acoustic waveguide where the outside temperature profile is transferred to a chosen gas contained inside the guide.

  16. Minimizing Uncertainty in Cryogenic Surface Figure Measurement

    Science.gov (United States)

    Blake, Peter; Mink, Ronald G.; Chambers, John; Robinson, F. David; Content, David; Davila, Pamela

    2005-01-01

    A new facility at the Goddard Space Flight Center is designed to measure with unusual accuracy the surface figure of mirrors at cryogenic temperatures down to 12 K. The facility is currently configured for spherical mirrors with a radius of curvature (ROC) of 600 mm, and apertures of about 150 mm or less. The goals of the current experiment were to 1) Obtain the best possible estimate of test mirror surface figure, S(x,y) at 87 K and 20 K; 2) Obtain the best estimate of the cryo-change, Delta (x,y): the change in surface figure between room temperature and the two cryo-temperatures; and 3) Determine the uncertainty of these measurements, using the definitions and guidelines of the ISO Guide to the Expression of Uncertainty in Measurement. A silicon mirror was tested, and the cry-change from room temperature to 20K was found to be 3.7 nm rms, with a standard uncertainty of 0.23 nm in the rms statistic. Both the cryo-change figure and the uncertainty are among the lowest such figures yet published. This report describes the facilities, experimental methods, and uncertainty analysis of the measurements.

  17. High-resolution humidity profiles retrieved from wind profiler radar measurements

    Science.gov (United States)

    Saïd, Frédérique; Campistron, Bernard; Di Girolamo, Paolo

    2018-03-01

    The retrieval of humidity profiles from wind profiler radars has already been documented in the past 30 years and is known to be neither as straightforward and nor as robust as the retrieval of the wind velocity. The main constraint to retrieve the humidity profile is the necessity to combine measurements from the wind profiler and additional measurements (such as observations from radiosoundings at a coarser time resolution). Furthermore, the method relies on some assumptions and simplifications that restrict the scope of its application. The first objective of this paper is to identify the obstacles and limitations and solve them, or at least define the field of applicability. To improve the method, we propose using the radar capacity to detect transition levels, such as the top level of the boundary layer, marked by a maximum in the radar reflectivity. This forces the humidity profile from the free troposphere and from the boundary layer to coincide at this level, after an optimization of the calibration coefficients, and reduces the error. The resulting mean bias affecting the specific humidity profile never exceeds 0.25 g kg-1. The second objective is to explore the capability of the algorithm to retrieve the humidity vertical profiles for an operational purpose by comparing the results with observations from a Raman lidar.

  18. Exploration of ion temperature profile measurements at JET using the upgraded neutron profile monitor

    International Nuclear Information System (INIS)

    Marocco, D.; Esposito, B.; Riva, M.

    2012-01-01

    The neutron profile monitor (NPM), routinely used at the Joint European Torus for neutron emissivity profile measurements, consists of two fan-shaped arrays of collimators and each line of sight (LOS) is equipped with a NE213 liquid organic scintillator for simultaneous measurements of the 2.5 MeV and 14 MeV neutrons. A digital system developed in ENEA has replaced the analog acquisition electronics and now enables the NPM to perform spatially resolved neutron spectrometry by providing neutron pulse height spectra (PHS) for each LOS. However, the NPM was not originally designed as a spectrometer and, therefore, lacks several key features, such as detailed measurements of the detector response functions and the presence of detector stability monitors. We present a proof of principle of ion temperature profile measurements derived from the NPM PHS in high plasma current discharges using simulated detector response functions.

  19. An array for measuring detailed soil temperature profiles

    Science.gov (United States)

    Soil temperature dynamics can provide insights into soil variables which are much more difficult or impossible to measure. We designed an array to measure temperature at precise depth increments. Data was collected to determine if the construction materials influence surface and near-surface tempera...

  20. Quantitative depth profiling of near surface semiconductor structures using ultra low energy SIMS analysis

    International Nuclear Information System (INIS)

    Elliner, D.I.

    1999-09-01

    The continual reduction in size of semiconductor structures and depths of junctions is putting a greater strain on characterization techniques. Accurate device and process modelling requires quantified electrical and dopant profiles from the topmost few nanometres. Secondary ion mass spectrometry (SIMS) is an analytical technique commonly used in the semiconductor industry to measure concentration depth profiles. To allow the quantification of the features that are closer to the surface, lower energy ions are employed, which also improves the available depth resolution. The development of the floating ion gun (FLIG) has made it possible to use sub keV beam energies on a routine basis, allowing quantified dopant profiles to be obtained within the first few nanometres of the surface. This thesis demonstrates that, when profiling with oxygen ion beams, greatest certainty in the retained dose is achieved at normal incidence, and when analysing boron accurate profile shapes are only obtained when the primary beam energy is less than half that of the implant. It was shown that it is now possible to profile, though with slower erosion rates and a limited dynamic range, with 100 eV oxygen (0 2 + ) ion beams. Profile features that had developed during rapid thermal annealing, that could only be observed when ultra low energy ion beams were used, were investigated using various analytical techniques. Explanations of the apparently inactive dopant were proposed, and included suggestions for cluster molecules. The oxide thickness of fully formed altered layers has also been investigated. The results indicate that a fundamental change in the mechanism of oxide formation occurs, and interfaces that are sharper than those grown by thermal oxidation can be produced using sub-keV ion beams. (author)

  1. Radioimmunoassay to quantitatively measure cell surface immunoglobulins

    International Nuclear Information System (INIS)

    Krishman, E.C.; Jewell, W.R.

    1975-01-01

    A radioimmunoassay techniques developed to quantitatively measure the presence of immunoglobulins on the surface of cells, is described. The amount of immunoglobulins found on different tumor cells varied from 200 to 1140 ng/10 6 cells. Determination of immunoglobulins on the peripheral lymphocytes obtained from different cancer patients varied between 340 to 1040 ng/10 6 cells. Cultured tumor cells, on the other hand, were found to contain negligible quantities of human IgG [pt

  2. Description of measurement techniques for surface contaminations

    International Nuclear Information System (INIS)

    Bourrez, E.

    2001-01-01

    The needs of evaluation of the surface contamination are numerous in the processes of production and management of radioactive waste. The market of radiation protection materials proposes a lot of devices answering to the almost all these needs. These device have however their conditions and particular limits for use. To realize correct measurements it is use the device, the technique and the methods adapted to the need, by taking into account the optimization of economical aspect. (N.C.)

  3. Profile Curvature Derivative Surface used to characterize the complexity of the seafloor around St. John, USVI

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Profile curvature was calculated from the bathymetry surface for each raster cell using the ArcGIS 3D Analyst "Curvature" Tool. Profile curvature describes the rate...

  4. Surface profiling of lithium with a laser-desorption mass-spectrometer microprobe

    International Nuclear Information System (INIS)

    Bickel, G.A.; Adams, H.M.

    1999-01-01

    A laser-desorption mass-spectrometer microprobe has been developed to profile Li distributions on the crevice surfaces of Cr-plated rolled-joint hubs. A single laser pulse is used to desorb and ionize the surface species followed by detection of Li + in a time-of-flight mass spectrometer. Images of the surface Li distribution are obtained with are solution of <10 μm. These images are directly compared with Li images from the more conventional secondary ion mass spectrometry technique and evaluated with respect to surface topographical features measured by secondary electron microscopy and atomic force microscopy. The laser-desorption images are shown to provide the same qualitative information as that available from secondary ion mass spectrometry. (author)

  5. Simultaneous measurements of top surface and its underlying film surfaces in multilayer film structure.

    Science.gov (United States)

    Ghim, Young-Sik; Rhee, Hyug-Gyo; Davies, Angela

    2017-09-19

    With the growth of 3D packaging technology and the development of flexible, transparent electrodes, the use of multilayer thin-films is steadily increasing throughout high-tech industries including semiconductor, flat panel display, and solar photovoltaic industries. Also, this in turn leads to an increase in industrial demands for inspection of internal analysis. However, there still remain many technical limitations to overcome for measurement of the internal structure of the specimen without damage. In this paper, we propose an innovative optical inspection technique for simultaneous measurements of the surface and film thickness corresponding to each layer of multilayer film structures by computing the phase and reflectance over a wide range of wavelengths. For verification of our proposed method, the sample specimen of multilayer films was fabricated via photolithography process, and the surface profile and film thickness of each layer were measured by two different techniques of a stylus profilometer and an ellipsometer, respectively. Comparison results shows that our proposed technique enables simultaneous measurements of the top surface and its underlying film surfaces with high precision, which could not be measured by conventional non-destructive methods.

  6. Objective measurement of inhaler inhalation flow profile using acoustic methods

    Energy Technology Data Exchange (ETDEWEB)

    Lacalle, H.; Taylor, T.E.; Marco, S.; Reilly, R.B.

    2016-07-01

    Patients with asthma and chronic obstructive pulmonary diseases (COPD) are mostly treated with inhalers that deliver medication directly to their airways. Drug delivery from dry powder inhalers (DPIs) is very much reliant on the inhalation manoeuvre, specifically the peak inspiratory flow rate (PIFR), inspiratory capacity (IC) and inhalation rise time (IRT) of the inhalation. It has been widely reported that patients may not follow correct inhalation technique while using their inhaler. In this study, a novel acoustic method is proposed to accurately estimate inhalation flow profile using only one inhalation recording for calibration. An Ellipta DPI was placed inside an airtight container with a spirometer connected in order to measure inhalation flow parameters. An acoustic recording device (Inhaler Compliance Assessment (INCA)) was also attached to the DPI. Inhalation audio and flow signals were recorded simultaneously. The data were collected from 20 healthy subjects while performing inhaler inhalations at a range of inspiratory flow rates. A power law regression model was computed to obtain the relationship between the acoustic envelope of the inhalation and flow profile of each recording. Each model was tested on the remaining audio signals to estimate flow profile. The average estimation error was found to be 10.5±0.3% for estimating flow profile from audio signals. Inhalation flow profile parameters (PIFR, IC and IRT) could then be measured from the estimated flow profile with high accuracy giving information on user inhalation technique. This method may assist in improving patient inhaler adherence and overall disease control. (Author)

  7. Gamma-ray emission profile measurements during JET ICRH discharges

    Energy Technology Data Exchange (ETDEWEB)

    Jarvis, O.N.; Marcus, F.B.; Sadler, G.; Van Belle, P. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Howarth, P.J.A. [Birmingham Univ. (United Kingdom); Adams, J.M.; Bond, D.S. [UKAEA Harwell Lab. (United Kingdom). Energy Technology Div.

    1994-07-01

    Gamma-ray emission from plasma-impurity reactions caused by minority ICRH accelerating fuel ions to MeV energies has been measured using the JET neutron profile monitor. A successful data analysis technique has been used to isolate the RF-induced gamma-ray emission that was detected, enabling profiles of gamma-ray emission to be obtained. The 2-d gamma-ray emission profiles show that virtually all the radiation originates from the low field side of the RF resonance layer, as expected from RF-induced pitch angle diffusion. The emission profiles indicate the presence of a small population of resonant {sup 3}He ions that possess orbits lying near the passing-trapped boundary. 6 refs., 4 figs.

  8. Temperature profile and other data from surface measurements casts from the R/V ATLANTIC in a world-wide survey from 17 March 1900 to 08 March 1998 (NODC Accession 0000241)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and other data were collected from the R/V ATLANTIC in a world-wide distribution from March 17, 1900 to March 8, 1996. Data were collected by...

  9. Acoustic Impedance Measurement for Underground Surfaces.

    Science.gov (United States)

    Cockcroft, Paul William

    Available from UMI in association with The British Library. Requires signed TDF. This thesis investigates the measurement of acoustic impedance for surfaces likely to be found in underground coal mines. By introducing the concepts of industrial noise, the effects of noise on the ear and relevant legislation the need for the protection of workers can be appreciated. Representative acoustic impedance values are vital as input for existing computer models that predict sound levels in various underground environments. These enable the mining engineer to predict the noise level at any point within a mine in the vicinity of noisy machinery. The concepts of acoustic intensity and acoustic impedance are investigated and different acoustic impedance measurement techniques are detailed. The possible use of either an impedance tube or an intensity meter for these kinds of measurements are suggested. The problems with acoustic intensity and acoustic impedance measurements are discussed with reference to the restraints that an underground environment imposes on any measurement technique. The impedance tube method for work in an acoustics laboratory is shown and the theory explained, accompanied by a few representative results. The use of a Metravib intensity meter in a soundproof chamber to gain impedance values is explained in detail. The accompanying software for the analysis of the two measured pressure signals is shown as well as the actual results for a variety of test surfaces. The use of a Nagra IV-SJ tape recorder is investigated to determine the effect of recording on the measurement and subsequent analysis of the input signals, particularly with reference to the phase difference introduced between the two simultaneous pressure signals. The subsequent use of a Norwegian Electronic intensity meter, including a proposal for underground work, is shown along with results for tests completed with this piece of equipment. Finally, recommendations are made on how to link up

  10. Mixing height measurements from UHF wind profiling radar

    Energy Technology Data Exchange (ETDEWEB)

    Angevine, W.M.; Grimsdell, A.W. [CIRES, Univ. of Colorado, and NOAA Aeronomy Lab., Boulder, Colorado (United States)

    1997-10-01

    Mixing height in convective boundary layers can be detected by wind profiling radars (profilers) operating at or near 915 MHZ. We have made such measurements in a variety of settings including Alabama in 1992; Nova Scotia, Canada, during the North Atlantic Regional Experiment (NARE) 1993; Tennessee during the Southern Oxidant Study (SOS) 1994; near a 450 m tower in Wisconsin in 1995; and extensively in Illinois during the Flatland95, `96, and `97 experiments, as well as continuous operations at the Flatland Atmospheric Observatory. Profiler mixing height measurements, like all measurements, are subject to some limitations. The most important of these are due to rainfall, minimum height, and height resolution. Profilers are very sensitive to rain, which dominates the reflectivity and prevents the mixing height from being detected. Because the best height resolution is currently 60 m and the minimum height is 120-150 m AGL, the profiler is not suited for detecting mixing height in stable or nocturnal boundary layers. Problems may also arise in very dry or cold environments. (au) 12 refs.

  11. Measuring the Valence of Nanocrystal Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Owen, Jonathan Scharle [Columbia Univ., New York, NY (United States)

    2016-11-30

    The goal of this project is to understand and control the interplay between nanocrystal stoichiometry, surface ligand binding and exchange, and the optoelectronic properties of semiconductor nanocrystals in solution and in thin solid films. We pursued three research directions with this goal in mind: 1) We characterized nanocrystal stoichiometry and its influence on the binding of L-type and X-type ligands, including the thermodynamics of binding and the kinetics of ligand exchange. 2) We developed a quantitative understanding of the relationship between surface ligand passivation and photoluminescence quantum yield. 3) We developed methods to replace the organic ligands on the nanocrystal with halide ligands and controllably deposit these nanocrystals into thin films, where electrical measurements were used to investigate the electrical transport and internanocrystal electronic coupling.

  12. Design and verification of the miniature optical system for small object surface profile fast scanning

    Science.gov (United States)

    Chi, Sheng; Lee, Shu-Sheng; Huang, Jen, Jen-Yu; Lai, Ti-Yu; Jan, Chia-Ming; Hu, Po-Chi

    2016-04-01

    As the progress of optical technologies, different commercial 3D surface contour scanners are on the market nowadays. Most of them are used for reconstructing the surface profile of mold or mechanical objects which are larger than 50 mm×50 mm× 50 mm, and the scanning system size is about 300 mm×300 mm×100 mm. There are seldom optical systems commercialized for surface profile fast scanning for small object size less than 10 mm×10 mm×10 mm. Therefore, a miniature optical system has been designed and developed in this research work for this purpose. Since the most used scanning method of such system is line scan technology, we have developed pseudo-phase shifting digital projection technology by adopting projecting fringes and phase reconstruction method. A projector was used to project a digital fringe patterns on the object, and the fringes intensity images of the reference plane and of the sample object were recorded by a CMOS camera. The phase difference between the plane and object can be calculated from the fringes images, and the surface profile of the object was reconstructed by using the phase differences. The traditional phase shifting method was accomplished by using PZT actuator or precisely controlled motor to adjust the light source or grating and this is one of the limitations for high speed scanning. Compared with the traditional optical setup, we utilized a micro projector to project the digital fringe patterns on the sample. This diminished the phase shifting processing time and the controlled phase differences between the shifted phases become more precise. Besides, the optical path design based on a portable device scanning system was used to minimize the size and reduce the number of the system components. A screwdriver section about 7mm×5mm×5mm has been scanned and its surface profile was successfully restored. The experimental results showed that the measurement area of our system can be smaller than 10mm×10mm, the precision reached to

  13. Retrieving vertical ozone profiles from measurements of global spectral irradiance

    Directory of Open Access Journals (Sweden)

    G. Bernhard

    2017-12-01

    Full Text Available A new method is presented to determine vertical ozone profiles from measurements of spectral global (direct Sun plus upper hemisphere irradiance in the ultraviolet. The method is similar to the widely used Umkehr technique, which inverts measurements of zenith sky radiance. The procedure was applied to measurements of a high-resolution spectroradiometer installed near the centre of the Greenland ice sheet. Retrieved profiles were validated with balloon-sonde observations and ozone profiles from the space-borne Microwave Limb Sounder (MLS. Depending on altitude, the bias between retrieval results presented in this paper and MLS observations ranges between −5 and +3 %. The magnitude of this bias is comparable, if not smaller, to values reported in the literature for the standard Dobson Umkehr method. Total ozone columns (TOCs calculated from the retrieved profiles agree to within 0.7±2.0 % (±1σ with TOCs measured by the Ozone Monitoring Instrument on board the Aura satellite. The new method is called the Global-Umkehr method.

  14. Retrieval of ozone profiles from GOMOS limb scattered measurements

    Directory of Open Access Journals (Sweden)

    S. Tukiainen

    2011-04-01

    Full Text Available The GOMOS (Global Ozone Monitoring by Occultation of Stars instrument on board the Envisat satellite measures the vertical composition of the atmosphere using the stellar occultation technique. While the night-time occultations of GOMOS have been proven to be of good quality, the daytime occultations are more challenging due to weaker signal-to-noise ratio. During daytime GOMOS measures limb scattered solar radiation in addition to stellar radiation. In this paper we introduce a retrieval method that determines ozone profiles between 20–60 km from GOMOS limb scattered solar radiances. GOMOS observations contain a considerable amount of stray light at high altitudes. We introduce a method for removing stray light and demonstrate its feasibility by comparing the corrected radiances against those measured by the OSIRIS (Optical Spectrograph & Infra Red Imaging System instrument. For the retrieval of ozone profiles, a standard onion peeling method is used. The first comparisons with other data sets suggest that the retrieved ozone profiles in 22–50 km are within 10% compared with the GOMOS night-time occultations and within 15% compared with OSIRIS. GOMOS has measured about 350 000 daytime profiles since 2002. The retrieval method presented here makes this large amount of data available for scientific use.

  15. Evaluation of Arctic broadband surface radiation measurements

    Directory of Open Access Journals (Sweden)

    N. Matsui

    2012-02-01

    Full Text Available The Arctic is a challenging environment for making in-situ surface radiation measurements. A standard suite of radiation sensors is typically designed to measure incoming and outgoing shortwave (SW and thermal infrared, or longwave (LW, radiation. Enhancements may include various sensors for measuring irradiance in narrower bandwidths. Many solar radiation/thermal infrared flux sensors utilize protective glass domes and some are mounted on complex mechanical platforms (solar trackers that keep sensors and shading devices trained on the sun along its diurnal path. High quality measurements require striking a balance between locating stations in a pristine undisturbed setting free of artificial blockage (such as from buildings and towers and providing accessibility to allow operators to clean and maintain the instruments. Three significant sources of erroneous data in the Arctic include solar tracker malfunctions, rime/frost/snow deposition on the protective glass domes of the radiometers and operational problems due to limited operator access in extreme weather conditions. In this study, comparisons are made between the global and component sum (direct [vertical component] + diffuse SW measurements. The difference between these two quantities (that theoretically should be zero is used to illustrate the magnitude and seasonality of arctic radiation flux measurement problems. The problem of rime/frost/snow deposition is investigated in more detail for one case study utilizing both SW and LW measurements. Solutions to these operational problems that utilize measurement redundancy, more sophisticated heating and ventilation strategies and a more systematic program of operational support and subsequent data quality protocols are proposed.

  16. Conditioning a segmented stem profile model for two diameter measurements

    Science.gov (United States)

    Raymond L. Czaplewski; Joe P. Mcclure

    1988-01-01

    The stem profile model of Max and Burkhart (1976) is conditioned for dbh and a second upper stem measurement. This model was applied to a loblolly pine data set using diameter outside bark at 5.3m (i.e., height of 17.3 foot Girard form class) as the second upper stem measurement, and then compared to the original, unconditioned model. Variance of residuals was reduced...

  17. Binary similarity measures for fingerprint analysis of qualitative metabolomic profiles.

    Science.gov (United States)

    Rácz, Anita; Andrić, Filip; Bajusz, Dávid; Héberger, Károly

    2018-01-01

    Contemporary metabolomic fingerprinting is based on multiple spectrometric and chromatographic signals, used either alone or combined with structural and chemical information of metabolic markers at the qualitative and semiquantitative level. However, signal shifting, convolution, and matrix effects may compromise metabolomic patterns. Recent increase in the use of qualitative metabolomic data, described by the presence (1) or absence (0) of particular metabolites, demonstrates great potential in the field of metabolomic profiling and fingerprint analysis. The aim of this study is a comprehensive evaluation of binary similarity measures for the elucidation of patterns among samples of different botanical origin and various metabolomic profiles. Nine qualitative metabolomic data sets covering a wide range of natural products and metabolomic profiles were applied to assess 44 binary similarity measures for the fingerprinting of plant extracts and natural products. The measures were analyzed by the novel sum of ranking differences method (SRD), searching for the most promising candidates. Baroni-Urbani-Buser (BUB) and Hawkins-Dotson (HD) similarity coefficients were selected as the best measures by SRD and analysis of variance (ANOVA), while Dice (Di1), Yule, Russel-Rao, and Consonni-Todeschini 3 ranked the worst. ANOVA revealed that concordantly and intermediately symmetric similarity coefficients are better candidates for metabolomic fingerprinting than the asymmetric and correlation based ones. The fingerprint analysis based on the BUB and HD coefficients and qualitative metabolomic data performed equally well as the quantitative metabolomic profile analysis. Fingerprint analysis based on the qualitative metabolomic profiles and binary similarity measures proved to be a reliable way in finding the same/similar patterns in metabolomic data as that extracted from quantitative data.

  18. Calibration of areal surface topography measuring instruments

    Science.gov (United States)

    Seewig, J.; Eifler, M.

    2017-06-01

    The ISO standards which are related to the calibration of areal surface topography measuring instruments are the ISO 25178-6xx series which defines the relevant metrological characteristics for the calibration of different measuring principles and the ISO 25178-7xx series which defines the actual calibration procedures. As the field of areal measurement is however not yet fully standardized, there are still open questions to be addressed which are subject to current research. Based on this, selected research results of the authors in this area are presented. This includes the design and fabrication of areal material measures. For this topic, two examples are presented with the direct laser writing of a stepless material measure for the calibration of the height axis which is based on the Abbott- Curve and the manufacturing of a Siemens star for the determination of the lateral resolution limit. Based on these results, as well a new definition for the resolution criterion, the small scale fidelity, which is still under discussion, is presented. Additionally, a software solution for automated calibration procedures is outlined.

  19. Measurements of electron density profiles using an angular filter refractometer

    Energy Technology Data Exchange (ETDEWEB)

    Haberberger, D., E-mail: dhab@lle.rochester.edu; Ivancic, S.; Hu, S. X.; Boni, R.; Barczys, M.; Craxton, R. S.; Froula, D. H. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14636 (United States)

    2014-05-15

    A novel diagnostic technique, angular filter refractometry (AFR), has been developed to characterize high-density, long-scale-length plasmas relevant to high-energy-density physics experiments. AFR measures plasma densities up to 10{sup 21} cm{sup −3} with a 263-nm probe laser and is used to study the plasma expansion from CH foil and spherical targets that are irradiated with ∼9 kJ of ultraviolet (351-nm) laser energy in a 2-ns pulse. The data elucidate the temporal evolution of the plasma profile for the CH planar targets and the dependence of the plasma profile on target radius for CH spheres.

  20. Effective aerodynamic roughness estimated from airborne laser altimeter measurements of surface features

    NARCIS (Netherlands)

    De Vries, AC; Kustas, WP; Ritchie, JC; Klaassen, W; Menenti, M; Rango, A; Prueger, JH

    2003-01-01

    Aerodynamic roughness length (z(0)) and displacement height (d(0)) are important surface parameters for estimating surface fluxes in numerical models. These parameters are generally determined from wind flow characteristics using logarithmic wind profiles measured at a meteorological tower or by

  1. Seasonal slope surface deformation measured with TLS

    International Nuclear Information System (INIS)

    Fan, L; Smethurst, J; Powrie, W; Sellaiya, A

    2014-01-01

    In temperate European climates, soil water removal due to vegetation transpiration peaks in summer and soil rewetting from higher levels of precipitation occurs in winter. In clays of high plasticity, the seasonal cycles of drying and wetting cause the soil to experience a volumetric change, resulting in seasonal shrinking and swelling. For a clay slope exhibiting volume change, such behaviour can lead to excessive deformation and could contribute to strain-softening and progressive slope failure. This can in turn cause traffic disruption and loss of life if roads and railways are founded on or surrounded by such slopes. This paper discusses the driving forces of seasonal surface movement, in particular the role of vegetation, and presents the use of Terrestrial Laser Scanning (TLS) to measure the surface movement of a lightly vegetated London Clay slope near Newbury, UK. Two TLS scans were carried out in early and late summer respectively, representing relative wet and dry conditions of the slope. Continuous field measurements of soil water content in upper layers of the slope were obtained from TDR ThetaProbes already installed at the site. The water content data are used to support the results obtained from TLS by indicating the likely volumetric change in the soil due to loss of water

  2. High resolution measurement of the velocity profiles of channel flows using the particle image velocimetry technique

    International Nuclear Information System (INIS)

    Nor Azizi Mohamed

    2000-01-01

    The high resolution velocity profiles of a uniform steady channel flow and a flow beneath waves were obtained using the particle image velocimetry (PIV) technique. The velocity profiles for each flow were calculated for both components. It is shown that the profiles obtained are very precise, displaying the point velocities from a few millimeters from the bottom of the channel up to the water surface across the water depth. In the case of the wave-induced flow, the profiles are shown under the respective wave phases and given in a plane representation. High resolution measurement of point velocities in a flow is achievable using PIV and invaluable when applied to a complex flow. (Author)

  3. Antiproton beam profile measurements using Gas Electron Multipliers

    CERN Document Server

    Duarte Pinto, Serge; Spanggaard, Jens; Tranquille, Gerard

    2011-01-01

    The new beam profile measurement for the Antiproton Decelerator (AD) at CERN is based on a single Gas Electron Multiplier (GEM) with a 2D readout structure. This detector is very light, ~0.4% X_0, as required by the low energy of the antiprotons, 5.3 MeV. This overcomes the problems previously encountered with multi-wire proportional chambers (MWPC) for the same purpose, where beam interactions with the detector severely affect the obtained profiles. A prototype was installed and successfully tested in late 2010, with another five detectors now installed in the ASACUSA and AEgIS beam lines. We will provide a detailed description of the detector and discuss the results obtained. The success of these detectors in the AD makes GEM-based detectors likely candidates for upgrade of the beam profile monitors in all experimental areas at CERN. The various types of MWPC currently in use are aging and becoming increasingly difficult to maintain.

  4. Lidar method of measurement of atmospheric extinction and ozone profiles

    Science.gov (United States)

    Cooney, J. A.

    1986-01-01

    A description of a method of measurement of atmospheric extinction and of ozone profiles by use of the backscatter signal from a monostatic lidar is given. The central feature of the procedure involves a measurement of the ratio of the Raman backscatter returns of both the oxygen and nitrogen atmospheric content. Because the ratio of the number density of both species is known to high accuracy, the measurement itself becomes a measure of the ratio of two transmissions to altitude along with a ratio of the two system constants. The calibration measurement for determining the value of the ratio of the two system constants or electro-optical conversion constants is accomplished by a lidar measurement of identical atmospheric targets while at the same time interchanging the two optical filters in the two optical channels of the receiver. More details of the procedure are discussed. Factoring this calibrated value into the measured O2/N2 profile ratio provides a measured value of the ratio of the two transmissions. Or equivalently, it provides a measurement of the difference of the two extinction coefficients at the O2 and N2 Raman wavelengths as a function of the height.

  5. Probing the surface profile and friction behavior of heterogeneous polymers: a molecular dynamics study

    Science.gov (United States)

    Dai, L.; Sorkin, V.; Zhang, Y. W.

    2017-04-01

    We perform molecular dynamics simulations to investigate molecular structure alternation and friction behavior of heterogeneous polymer (perfluoropolyether) surfaces using a nanoscale probing tip (tetrahedral amorphous carbon). It is found that depending on the magnitude of the applied normal force, three regimes exist: the shallow depth-sensing (SDS), deep depth-sensing (DDS), and transitional depth-sensing (TDS) regimes; TDS is between SDS and DDS. In SDS, the tip is floating on the polymer surface and there is insignificant permanent alternation in the polymer structure due to largely recoverable atomic deformations, and the surface roughness profile can be accurately measured. In DDS, the tip is plowing through the polymer surface and there is significant permanent alternation in the molecular structure. In this regime, the lateral friction force rises sharply and fluctuates violently when overcoming surface pile-ups. In SDS, the friction can be described by a modified Amonton’s law including the adhesion effect; meanwhile, in DDS, the adhesion effect is negligible but the friction coefficient is significantly higher. The underlying reason for the difference in these regimes rests upon different contributions by the repulsion and attraction forces between the tip and polymer surfaces to the friction force. Our findings here reveal important insights into lateral depth-sensing on heterogeneous polymer surfaces and may help improve the precision of depth-sensing devices.

  6. Transcriptome-wide measurement of ribosomal occupancy by ribosome profiling.

    Science.gov (United States)

    Aeschimann, Florian; Xiong, Jieyi; Arnold, Andreas; Dieterich, Christoph; Grosshans, Helge

    2015-09-01

    Gene expression profiling provides a tool to analyze the internal states of cells or organisms, and their responses to perturbations. While global measurements of mRNA levels have thus been widely used for many years, it is only through the recent development of the ribosome profiling technique that an analogous examination of global mRNA translation programs has become possible. Ribosome profiling reveals which RNAs are being translated to what extent and where the translated open reading frames are located. In addition, different modes of translation regulation can be distinguished and characterized. Here, we present an optimized, step-by-step protocol for ribosome profiling. Although established in Caenorhabditis elegans, our protocol and optimization approaches should be equally usable for other model organisms or cell culture with little adaptation. Next to providing a protocol, we compare two different methods for isolation of single ribosomes and two different library preparations, and describe strategies to optimize the RNase digest and to reduce ribosomal RNA contamination in the libraries. Moreover, we discuss bioinformatic strategies to evaluate the quality of the data and explain how the data can be analyzed for different applications. In sum, this article seeks to facilitate the understanding, execution, and optimization of ribosome profiling experiments. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Calibrating system errors of large scale three-dimensional profile measurement instruments by subaperture stitching method.

    Science.gov (United States)

    Dong, Zhichao; Cheng, Haobo; Feng, Yunpeng; Su, Jingshi; Wu, Hengyu; Tam, Hon-Yuen

    2015-07-01

    This study presents a subaperture stitching method to calibrate system errors of several ∼2  m large scale 3D profile measurement instruments (PMIs). The calibration process was carried out by measuring a Φ460  mm standard flat sample multiple times at different sites of the PMI with a length gauge; then the subaperture data were stitched together using a sequential or simultaneous stitching algorithm that minimizes the inconsistency (i.e., difference) of the discrete data in the overlapped areas. The system error can be used to compensate the measurement results of not only large flats, but also spheres and aspheres. The feasibility of the calibration was validated by measuring a Φ1070  mm aspheric mirror, which can raise the measurement accuracy of PMIs and provide more reliable 3D surface profiles for guiding grinding, lapping, and even initial polishing processes.

  8. Sea Surface Temperatures (SST): Significance and Measurement

    Science.gov (United States)

    Singer, S. F.

    2006-05-01

    Oceans cover 71 percent of Earth's surface and control the global climate. Quoted global mean temperature values and trends, largely based on land thermometers, differ substantially -" mainly because of uncertainties about SST. The ongoing controversy about the relative importance of natural climate changes and Anthropogenic Global Warming (AGW) revolves mainly around disparities between temperature trends of the atmosphere and surface (in the tropics and SH, i.e. mostly SST). Accurate measurement of SST is difficult. Geographic coverage is poor and there are many different techniques, each with its own problems and uncertainties: Water temperatures from buckets and ship-engine inlets; fixed and floating buoys; air temperatures from shipboard and island stations; and remote sensing from satellites using IR and microwaves. As is evident, each technique refers to a different level below the air-water interface. Drifter buoys (at around 50 cm) measure temperatures in the euphotic layers that are generally warmer than the bulk mixed layer sampled by ships (typically around 10 m). The IR emission arises from a 10-micron-thick skin that interacts dynamically with the underlying "mixed layer." The microwave data depend also on emissivity and therefore on surface roughness and sea state. SST data derived from corals provide some support for instrumental data but are not conclusive. The majority of corals show a warming trend since 1979; others show cooling or are ambiguous. There are different ways of interpreting this result. Physical optics dictates that the downwelling IR radiation from atmospheric greenhouse gases is absorbed in the first instance within the skin. Only direct measurements can establish how much of this energy is shared with the bulk mixed layer (to which the usual SST values refer.). SST controls evaporation and therefore global precipitation. SST influences tropical cyclones and sea-level rise; but there is lively debate on those issues. Changes in

  9. Surface topography measurements over the 1 meter to 10 micrometer spatial period bandwidth

    International Nuclear Information System (INIS)

    Takacs, P.Z.; Furenlid, K.; DeBiasse, R.A.; Church, E.L.

    1989-09-01

    A recently-developed long-trace surface profiling instrument (LTP) is now in operation in our laboratory measuring surface profiles on grazing incidence aspheres and also conventional optical surface. The LTP characterizes surface height profiles in a non-contact manner over spatial periods ranging from 1 meter (the maximum scan length) to 2 mm (the Nyquist period for 1 mm sampling period) and complements the range of our WYKO NCP-1000 2.5X surface roughness profiler (5 mm to 9.8 μm). Using these two instruments, we can fully characterize both figure and finish of an optical surface in the same way that we normally characterize surface finish, e.g., by means of the power spectral density function in the spatial frequency domain. A great deal of information about the distribution of figure errors over various spatial frequency ranges is available from this data, which is useful for process control and predicting performance at the desired wavelength and incidence angle. In addition, the LTP is able to measure the absolute radius of curvature on long-radius optics with high precision and accuracy. Angular errors in the optical head are measured in real time by an electronic autocollimator as the head traverses the linear air bearing slide. Measurements of kilometer radius optics can be made very quickly and the data analyzed in a format that is very easy to understand. 17 refs., 10 figs

  10. Quadrotor helicopter for surface hydrological measurements

    Science.gov (United States)

    Pagano, C.; Tauro, F.; Porfiri, M.; Grimaldi, S.

    2013-12-01

    Surface hydrological measurements are typically performed through user-assisted and intrusive field methodologies which can be inadequate to monitor remote and extended areas. In this poster, we present the design and development of a quadrotor helicopter equipped with digital acquisition system and image calibration units for surface flow measurements. This custom-built aerial vehicle is engineered to be lightweight, low-cost, highly customizable, and stable to guarantee optimal image quality. Quadricopter stability guarantees minimal vibrations during image acquisition and, therefore, improved accuracy in flow velocity estimation through large scale particle image velocimetry algorithms or particle tracking procedures. Stability during the vehicle pitching and rolling is achieved by adopting large arm span and high-wing configurations. Further, the vehicle framework is composed of lightweight aluminum and durable carbon fiber for optimal resilience. The open source Ardupilot microcontroller is used for remote control of the quadricopter. The microcontroller includes an inertial measurement unit (IMU) equipped with accelerometers and gyroscopes for stable flight through feedback control. The vehicle is powered by a 3 cell (11.1V) 3000 mAh Lithium-polymer battery. Electronic equipment and wiring are hosted into the hollow arms and on several carbon fiber platforms in the waterproof fuselage. Four 35A high-torque motors are supported at the far end of each arm with 10 × 4.7 inch propellers. Energy dissipation during landing is accomplished by four pivoting legs that, through the use of shock absorbers, prevent the impact energy from affecting the frame thus causing significant damage. The data capturing system consists of a GoPro Hero3 camera and in-house built camera gimbal and shock absorber damping device. The camera gimbal, hosted below the vehicle fuselage, is engineered to maintain the orthogonality of the camera axis with respect to the water surface by

  11. Surface measurement errors using commercial scanning white light interferometers

    International Nuclear Information System (INIS)

    Gao, F; Petzing, J; Coupland, J M; Leach, R K

    2008-01-01

    This paper examines the performance of commercial scanning white light interferometers in a range of measurement tasks. A step height artefact is used to investigate the response of the instruments at a discontinuity, while gratings with sinusoidal and rectangular profiles are used to investigate the effects of surface gradient and spatial frequency. Results are compared with measurements made with tapping mode atomic force microscopy and discrepancies are discussed with reference to error mechanisms put forward in the published literature. As expected, it is found that most instruments report errors when used in regions close to a discontinuity or those with a surface gradient that is large compared to the acceptance angle of the objective lens. Amongst other findings, however, we report systematic errors that are observed when the surface gradient is considerably smaller. Although these errors are typically less than the mean wavelength, they are significant compared to the vertical resolution of the instrument and indicate that current scanning white light interferometers should be used with some caution if sub-wavelength accuracy is required

  12. Surface measurement errors using commercial scanning white light interferometers

    Science.gov (United States)

    Gao, F.; Leach, R. K.; Petzing, J.; Coupland, J. M.

    2008-01-01

    This paper examines the performance of commercial scanning white light interferometers in a range of measurement tasks. A step height artefact is used to investigate the response of the instruments at a discontinuity, while gratings with sinusoidal and rectangular profiles are used to investigate the effects of surface gradient and spatial frequency. Results are compared with measurements made with tapping mode atomic force microscopy and discrepancies are discussed with reference to error mechanisms put forward in the published literature. As expected, it is found that most instruments report errors when used in regions close to a discontinuity or those with a surface gradient that is large compared to the acceptance angle of the objective lens. Amongst other findings, however, we report systematic errors that are observed when the surface gradient is considerably smaller. Although these errors are typically less than the mean wavelength, they are significant compared to the vertical resolution of the instrument and indicate that current scanning white light interferometers should be used with some caution if sub-wavelength accuracy is required.

  13. Dynamic measurements of depth profiles of hydrogen implanted into graphite at elevated temperatures

    International Nuclear Information System (INIS)

    Morita, K.; Ohtsuka, K.; Hasebe, Y.

    1989-01-01

    Time variations of depth profiles of hydrogen retained in graphite during and after implantation of 3 keV H 2 + ions have been studied from dynamic measurements by means of elastic recoil detection at temperatures between 300 and 1000 K and at ion fluxes of 4x10 13 , 2x10 14 and 4x10 14 /cm 2 s. It is shown that the maximum steady state concentration of hydrogens is about 6x10 22 /cm 3 at room temperature and is by a factor of 1.7 higher than the maximum static concentration after implantation. It is also shown that the depth profiles have the maximum at the projected range of implanted ions, the width of the profile broadens gradually inwards as the fluence and the temperature increase and the shapes of steady state profiles are almost the same as those of static profiles. By analytically solving mass balance equations for hydrogens, in which diffusion, trapping, ion-induced detrapping and recession of the surface are taken into account, the experimental steady state depth profiles are demonstrated to be well reproduced. The diffusion constants of hydrogen are determined as a function of temperature by fitting the calculated to the experimental depth profiles. (orig.)

  14. 128 slice computed tomography dose profile measurement using thermoluminescent dosimeter

    International Nuclear Information System (INIS)

    Salehhon, N; Hashim, S; Karim, M K A; Ang, W C; Musa, Y; Bahruddin, N A

    2017-01-01

    The increasing use of computed tomography (CT) in clinical practice marks the needs to understand the dose descriptor and dose profile. The purposes of the current study were to determine the CT dose index free-in-air (CTDI air ) in 128 slice CT scanner and to evaluate the single scan dose profile (SSDP). Thermoluminescent dosimeters (TLD-100) were used to measure the dose profile of the scanner. There were three sets of CT protocols where the tube potential (kV) setting was manipulated for each protocol while the rest of parameters were kept constant. These protocols were based from routine CT abdominal examinations for male adult abdomen. It was found that the increase of kV settings made the values of CTDI air increased as well. When the kV setting was changed from 80 kV to 120 kV and from 120 kV to 140 kV, the CTDI air values were increased as much as 147.9% and 53.9% respectively. The highest kV setting (140 kV) led to the highest CTDI air value (13.585 mGy). The p -value of less than 0.05 indicated that the results were statistically different. The SSDP showed that when the kV settings were varied, the peak sharpness and height of Gaussian function profiles were affected. The full width at half maximum (FWHM) of dose profiles for all protocols were coincided with the nominal beam width set for the measurements. The findings of the study revealed much information on the characterization and performance of 128 slice CT scanner. (paper)

  15. Profiling of aerosol concentrations, particle size distributions and relative humidity in the atmospheric surface layer over the North Sea

    NARCIS (Netherlands)

    Leeuw, G. de

    1990-01-01

    Results are presented from measurements in the lower 15 m of the marine atmospheric surface layer. The paper is focussed on the comparison of the profile data obtained with the Rotorod and the optical scatterometer. These instruments are based on different physical principles. Results show that

  16. Wind lidar profile measurements in the coastal boundary layer: comparison with WRF modelling

    DEFF Research Database (Denmark)

    Floors, Rogier; Pena Diaz, Alfredo; Vincent, Claire Louise

    2012-01-01

    We use measurements from a pulsed wind lidar to study the wind speed profile in the planetary boundary layer (PBL) up to 600 m above the surface at a coastal site. Due to the high availability and quality of wind lidar data and the high vertical range of the measurements, it is possible to study...... of the smooth-to-rough transition at the coastline. When using a more representative roughness than the default, the biases in the surface friction velocity and heat flux are reduced and the wind speed is slightly improved. Both PBL schemes show too much mixing during stable conditions and an underestimation...... in the amount of observed low level jet. The wind speed predicted by WRF does not improve when a higher resolution is used. Therefore, both the inhomogeneous (westerly) and homogeneous (easterly) flow contribute to a large negative bias in the mean wind speed profile at heights between 100 and 200 m....

  17. Measurement of plasma edge profile on Wendelstein 7-X

    Energy Technology Data Exchange (ETDEWEB)

    Drews, Philipp; Liang, Yunfeng; Neubauer, Olaf; Denner, Peter; Rack, Michael; Liu, Shaocheng; Wang, Nunchao; Nicolai, Dirk; Hollfeld, Klaus; Satheeswaran, Guruparan [Forschungszentrum Juelich, IEK4, Juelich (Germany); Grulke, Olaf [Max-Planck-Institut fuer Plasmaphysik, Greifswald (Germany); Collaboration: W7-X Team

    2016-07-01

    Wendelstein 7-X (W7-X), currently under commissioning at the IPP Greifswald, will be the world's largest stellarator with modular superconducting coils, which will enable steady-state-like plasma operation of up to thirty minutes in order to explore the reactor relevance of this concept. The first operation phase of W7-X will employ a limiter configuration. It will be used primarily for setting up the diagnostics and testing the magnetic configuration. In conjunction with the multipurpose manipulator, a fast reciprocating probe is installed. The combined probe head will be used to measure the radial distribution of the magnetic field using magnetic pick-up coils; the plasma temperature and density profiles and the radial electric field using Langmuir pins; and the plasma flows using a Mach setup. As a quasi-isodynamic stellarator, it has been predicted that not only neoclassical but also turbulent transport will be comparable to or possibly even lower than that of tokamaks. Edge plasma profile measurements, especially those of the electron temperature and density, will play a key role in validating this performance in comparison to the tokamak and hence the viability of a stellarator fusion reactor. The edge plasma profile measurements using the combined probe head are presented.

  18. Submicron Surface Vibration Profiling Using Doppler Self-Mixing Techniques

    Directory of Open Access Journals (Sweden)

    Tânia Pereira

    2014-01-01

    Full Text Available Doppler self-mixing laser probing techniques are often used for vibration measurement with very high accuracy. A novel optoelectronic probe solution is proposed, based on off-the-shelf components, with a direct reflection optical scheme for contactless characterization of the target’s movement. This probe was tested with two test bench apparatus that enhance its precision performance, with a linear actuator at low frequency (35 µm, 5–60 Hz, and its dynamics, with disc shaped transducers for small amplitude and high frequency (0.6 µm, 100–2500 Hz. The results, obtained from well-established signal processing methods for self-mixing Doppler signals, allowed the evaluation of vibration velocity and amplitudes with an average error of less than 10%. The impedance spectrum of piezoelectric (PZ disc target revealed a maximum of impedance (around 1 kHz for minimal Doppler shift. A bidimensional scan over the PZ disc surface allowed the categorization of the vibration mode (0, 1 and explained its deflection directions. The feasibility of a laser vibrometer based on self-mixing principles and supported by tailored electronics able to accurately measure submicron displacements was, thus, successfully demonstrated.

  19. Radial Surface Density Profiles of Gas and Dust in the Debris Disk around 49 Ceti

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, A. Meredith; Lieman-Sifry, Jesse; Flaherty, Kevin M.; Daley, Cail M. [Department of Astronomy, Van Vleck Observatory, Wesleyan University, 96 Foss Hill Drive, Middletown, CT 06459 (United States); Roberge, Aki [Exoplanets and Stellar Astrophysics Laboratory, NASA Goddard Space Flight Center, Code 667, Greenbelt, MD 20771 (United States); Kóspál, Ágnes; Moór, Attila; Ábrahám, Peter [Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, P.O. Box 67, 1525 Budapest (Hungary); Kamp, Inga [Kapteyn Astronomical Institute, University of Groningen, Postbus 800, 9700 AV Groningen (Netherlands); Wilner, David J.; Andrews, Sean M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51, Cambridge, MA 02138 (United States); Kastner, Joel H., E-mail: amhughes@astro.wesleyan.edu [Rochester Institute of Technology, 54 Lomb Memorial Drive, Rochester, NY 14623 (United States)

    2017-04-20

    We present ∼0.″4 resolution images of CO(3–2) and associated continuum emission from the gas-bearing debris disk around the nearby A star 49 Ceti, observed with the Atacama Large Millimeter/Submillimeter Array (ALMA). We analyze the ALMA visibilities in tandem with the broadband spectral energy distribution to measure the radial surface density profiles of dust and gas emission from the system. The dust surface density decreases with radius between ∼100 and 310 au, with a marginally significant enhancement of surface density at a radius of ∼110 au. The SED requires an inner disk of small grains in addition to the outer disk of larger grains resolved by ALMA. The gas disk exhibits a surface density profile that increases with radius, contrary to most previous spatially resolved observations of circumstellar gas disks. While ∼80% of the CO flux is well described by an axisymmetric power-law disk in Keplerian rotation about the central star, residuals at ∼20% of the peak flux exhibit a departure from axisymmetry suggestive of spiral arms or a warp in the gas disk. The radial extent of the gas disk (∼220 au) is smaller than that of the dust disk (∼300 au), consistent with recent observations of other gas-bearing debris disks. While there are so far only three broad debris disks with well characterized radial dust profiles at millimeter wavelengths, 49 Ceti’s disk shows a markedly different structure from two radially resolved gas-poor debris disks, implying that the physical processes generating and sculpting the gas and dust are fundamentally different.

  20. Thermocouple Rakes for Measuring Boundary Layer Flows Extremely Close to Surface

    Science.gov (United States)

    Hwang, Danny P.; Fralick, Gustave C.; Martin, Lisa C.; Blaha, Charles A.

    2001-01-01

    Of vital interest to aerodynamic researchers is precise knowledge of the flow velocity profile next to the surface. This information is needed for turbulence model development and the calculation of viscous shear force. Though many instruments can determine the flow velocity profile near the surface, none of them can make measurements closer than approximately 0.01 in. from the surface. The thermocouple boundary-layer rake can measure much closer to the surface than conventional instruments can, such as a total pressure boundary layer rake, hot wire, or hot film. By embedding the sensors (thermocouples) in the region where the velocity is equivalent to the velocity ahead of a constant thickness strut, the boundary-layer flow profile can be obtained. The present device fabricated at the NASA Glenn Research Center microsystem clean room has a heater made of platinum and thermocouples made of platinum and gold. Equal numbers of thermocouples are placed both upstream and downstream of the heater, so that the voltage generated by each pair at the same distance from the surface is indicative of the difference in temperature between the upstream and downstream thermocouple locations. This voltage differential is a function of the flow velocity, and like the conventional total pressure rake, it can provide the velocity profile. In order to measure flow extremely close to the surface, the strut is made of fused quartz with extremely low heat conductivity. A large size thermocouple boundary layer rake is shown in the following photo. The latest medium size sensors already provide smooth velocity profiles well into the boundary layer, as close as 0.0025 in. from the surface. This is about 4 times closer to the surface than the previously used total pressure rakes. This device also has the advantage of providing the flow profile of separated flow and also it is possible to measure simultaneous turbulence levels within the boundary layer.

  1. Reflectometry techniques for density profile measurements on fusion plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Laviron, C. [Association Euratom-CEA, Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Donne, A.J.H. [Associatie Euratom-FOM, Nieuwegein (Netherlands). FOM-Instituut voor Plasmafysica; Manso, M.E. [Instituto Superior Tecnico, Lisbon (Portugal). Lab. de Quimica Organica; Sanchez, J. [EURATOM-CIEMAT for Fusion Association, Madrid (Spain)

    1996-03-01

    Reflectometry applied to the measurement of density profiles on fusion plasmas has been subject to many recent developments. After a brief reminder of the principles of reflectometry, the theoretical accuracy of reflectometry measurements is discussed. The main difficulties limiting the performance, namely the plasma fluctuations and the quality of the transmission lines, are analysed. The different techniques used for reflectometry are then presented. The present status and achievements of actual implementations of these techniques are shown, with an analysis of their respective limitations and merits, as well as foreseen developments. (author). 70 refs.

  2. Doppler lidar measurement of profiles of turbulence and momentum flux

    Science.gov (United States)

    Eberhard, Wynn L.; Cupp, Richard E.; Healy, Kathleen R.

    1989-01-01

    A short-pulse CO2 Doppler lidar with 150-m range resolution measured vertical profiles of turbulence and momentum flux. Example measurements are reported of a daytime mixed layer with strong mechanical mixing caused by a wind speed of 15 m/sec, which exceeded the speed above the capping inversion. The lidar adapted an azimuth scanning technique previously demonstrated by radar. Scans alternating between two elevation angles allow determination of mean U-squared, V-squared, and W-squared. Expressions were derived to estimate the uncertainty in the turbulence parameters. A new processing method, partial Fourier decomposition, has less uncertainty than the filtering used earlier.

  3. Error in Radar-Derived Soil Moisture due to Roughness Parameterization: An Analysis Based on Synthetical Surface Profiles

    Directory of Open Access Journals (Sweden)

    Bernard De Baets

    2009-02-01

    Full Text Available In the past decades, many studies on soil moisture retrieval from SAR demonstrated a poor correlation between the top layer soil moisture content and observed backscatter coefficients, which mainly has been attributed to difficulties involved in the parameterization of surface roughness. The present paper describes a theoretical study, performed on synthetical surface profiles, which investigates how errors on roughness parameters are introduced by standard measurement techniques, and how they will propagate through the commonly used Integral Equation Model (IEM into a corresponding soil moisture retrieval error for some of the currently most used SAR configurations. Key aspects influencing the error on the roughness parameterization and consequently on soil moisture retrieval are: the length of the surface profile, the number of profile measurements, the horizontal and vertical accuracy of profile measurements and the removal of trends along profiles. Moreover, it is found that soil moisture retrieval with C-band configuration generally is less sensitive to inaccuracies in roughness parameterization than retrieval with L-band configuration.

  4. 3D Surface Profile and Color Stability of Tooth Colored Filling Materials after Bleaching.

    Science.gov (United States)

    Irawan, Bryant Anthony; Irawan, Stacey Natalie; Masudi, Sam'an Malik; Sukminingrum, Ninin; Alam, Mohammad Khursheed

    2015-01-01

    This study aims to evaluate the effects of vital tooth bleaching with carbamide peroxide home bleaching and in-office bleaching on the color stability and 3D surface profile of dental restorative filling materials. Thirty discs (n = 30) measure 6 mm in diameter and 2 mm thick for each of three restorative materials. These are nanofilled composite Filtek Z350 XT, the submicron composite Estelite Σ Quick, and nanofilled glass ionomer Ketac N100 nanoionomer and were fabricated in shade A2. Each group was further divided into three subgroups (n = 10): subgroup A (Opalescence PF), subgroup B (Opalescence Boost in-office bleaching), and subgroup C (distilled water) serving as control. Samples were bleached according to the manufacturer's instructions for a period of two weeks. The Commission Internationale de L'Eclairage (CIE L(*), a(*), b(*)) system was chosen for image processing, while 3D surface profile was tested with atomic force microscopy (AFM). Statistical analyses were performed with the Mann-Whitney tests and Krusal-Wallis with a P value of ≤ 0.05. The three restorative materials showed significant color changes (ΔE); P ≤ 0.05. In diminishing order, the mean color changes recorded were Estelite Σ (3.82 ± 1.6) > Ketac Nano (2.97 ± 1.2) > Filtek Z350 XT (2.25 ± 1.0). However, none of the tested materials showed statistically significant changes in surface roughness; P > 0.05.

  5. MODELLING AND VIBRATION ANALYSIS OF A ROAD PROFILE MEASURING SYSTEM

    Directory of Open Access Journals (Sweden)

    C. B. Patel

    2010-06-01

    Full Text Available During a vehicle development program, load data representing severe customer usage is required. The dilemma faced by a design engineer during the design process is that during the initial stage, only predicted loads estimated from historical targets are available, whereas the actual loads are available only at the fag end of the process. At the same time, changes required, if any, are easier and inexpensive during the initial stages of the design process whereas they are extremely costly in the latter stages of the process. The use of road profiles and vehicle models to predict the load acting on the whole vehicle is currently being researched. This work hinges on the ability to accurately measure road profiles. The objective of the work is to develop an algorithm, using MATLAB Simulink software, to convert the input signals into measured road profile. The algorithm is checked by the MATLAB Simulink 4 degrees of freedom half car model. To make the whole Simulink model more realistic, accelerometer and laser sensor properties are introduced. The present work contains the simulation of the mentioned algorithm with a half car model and studies the results in distance, time, and the frequency domain.

  6. Measurement of atmospheric surface layer turbulence using unmanned aerial vehicles

    Science.gov (United States)

    Bailey, Sean; Canter, Caleb

    2017-11-01

    We describe measurements of the turbulence within the atmospheric surface layer using highly instrumented and autonomous unmanned aerial vehicles (UAVs). Results from the CLOUDMAP measurement campaign in Stillwater Oklahoma are presented including turbulence statistics measured during the transition from stably stratified to convective conditions. The measurements were made using pre-fabricated fixed-wing remote-control aircraft adapted to fly autonomously and carry multi-hole pressure probes, pressure, temperature and humidity sensors. Two aircraft were flown simultaneously, with one flying a flight path intended to profile the boundary layer up to 100 m and the other flying at a constant fixed altitude of 50 m. The evolution of various turbulent statistics was determined from these flights, including Reynolds stresses, correlations, spectra and structure functions. These results were compared to those measured by a sonic anemometer located on a 7.5 m tower. This work was supported by the National Science Foundation through Grant #CBET-1351411 and by National Science Foundation award #1539070, Collaboration Leading Operational UAS Development for Meteorology and Atmospheric Physics (CLOUDMAP).

  7. Nuclear techniques for measuring moisture content in soil profiles

    International Nuclear Information System (INIS)

    Barrada, Y.

    1983-01-01

    The prevailing severe shortage of animal feed in most of the developing countries could, to a considerable extent, be overcome through improved range management, which includes introduction of high yielding drought-resistant forage crops, development of adequate water conservation measures, and as far as possible growing annual forage crops on part of the vast areas of arable land currently left fallow each year. Year round measurements are essential for a good understanding of soil water and nutrients dynamics, which allow for adequate evaluation of pasture management alternatives. The methods most commonly used for moisture measurements in soil profiles are discussed because such measurements are likely to form an essential part of any investigation aimed at increasing animal feed production through the development of adequate pasture management practices. (author)

  8. OCT-based profiler for automating ocular surface prosthetic fitting (Conference Presentation)

    Science.gov (United States)

    Mujat, Mircea; Patel, Ankit H.; Maguluri, Gopi N.; Iftimia, Nicusor V.; Patel, Chirag; Agranat, Josh; Tomashevskaya, Olga; Bonte, Eugene; Ferguson, R. Daniel

    2016-03-01

    The use of a Prosthetic Replacement of the Ocular Surface Environment (PROSE) device is a revolutionary treatment for military patients that have lost their eyelids due to 3rd degree facial burns and for civilians who suffer from a host of corneal diseases. However, custom manual fitting is often a protracted painful, inexact process that requires multiple fitting sessions. Training for new practitioners is a long process. Automated methods to measure the complete corneal and scleral topology would provide a valuable tool for both clinicians and PROSE device manufacturers and would help streamline the fitting process. PSI has developed an ocular anterior-segment profiler based on Optical Coherence Tomography (OCT), which provides a 3D measure of the surface of the sclera and cornea. This device will provide topography data that will be used to expedite and improve the fabrication process for PROSE devices. OCT has been used to image portions of the cornea and sclera and to measure surface topology for smaller contact lenses [1-3]. However, current state-of-the-art anterior eye OCT systems can only scan about 16 mm of the eye's anterior surface, which is not sufficient for covering the sclera around the cornea. In addition, there is no systematic method for scanning and aligning/stitching the full scleral/corneal surface and commercial segmentation software is not optimized for the PROSE application. Although preliminary, our results demonstrate the capability of PSI's approach to generate accurate surface plots over relatively large areas of the eye, which is not currently possible with any other existing platform. Testing the technology on human volunteers is currently underway at Boston Foundation for Sight.

  9. Employing Beam-Gas Interaction Vertices for Transverse Profile Measurements

    CERN Document Server

    Rihl, Mariana; Baglin, Vincent; Barschel, Colin; Bay, Aurelio; Blanc, Frederic; Bravin, Enrico; Bregliozzi, Giuseppe; Chritin, Nicolas; Dehning, Bernd; Ferro-Luzzi, Massimiliano; Gaspar, Clara; Gianì, Sebastiana; Giovannozzi, Massimo; Greim, Roman; Haefeli, Guido; Hopchev, Plamen; Jacobsson, Richard; Jensen, Lars; Jones, Owain Rhodri; Jurado, Nicolas; Kain, Verena; Karpinski, Waclaw; Kirn, Thomas; Kuhn, Maria; Luthi, Berengere; Magagnin, Paolo; Matev, Rosen; Nakada, Tatsuya; Neufeld, Niko; Panman, Jaap; Rakotomiaramanana, Barinjaka; Salustino Guimaraes, Valdir; Salvant, Benoit; Schael, Stefan; Schneider, Olivier; Schwering, Georg; Tobin, Mark; Veness, Raymond; Veyrat, Quentin; Vlachos, Sotiris; Wlochal, Michael; Xu, Zhirui; von Dratzig, Arndt

    2016-01-01

    Interactions of high-energy beam particles with residual gas offer a unique opportunity to measure the beam profile in a non-intrusive fashion. Such a method was successfully pioneered* at the LHCb experiment using a silicon microstrip vertex detector. During the recent Large Hadron Collider shutdown at CERN, a demonstrator Beam-Gas Vertexing system based on eight scintillating-fibre modules was designed**, constructed and installed on Ring 2 to be operated as a pure beam diagnostics device. The detector signals are read out and collected with LHCb-type front-end electronics and a DAQ system consisting of a CPU farm. Tracks and vertices will be reconstructed to obtain a beam profile in real time. Here, first commissioning results are reported. The advantages and potential for future applications of this technique are discussed.

  10. Automatic centroid detection and surface measurement with a digital Shack–Hartmann wavefront sensor

    International Nuclear Information System (INIS)

    Yin, Xiaoming; Zhao, Liping; Li, Xiang; Fang, Zhongping

    2010-01-01

    With the breakthrough of manufacturing technologies, the measurement of surface profiles is becoming a big issue. A Shack–Hartmann wavefront sensor (SHWS) provides a promising technology for non-contact surface measurement with a number of advantages over interferometry. The SHWS splits the incident wavefront into many subsections and transfers the distorted wavefront detection into the centroid measurement. So the accuracy of the centroid measurement determines the accuracy of the SHWS. In this paper, we have presented a new centroid measurement algorithm based on an adaptive thresholding and dynamic windowing method by utilizing image-processing techniques. Based on this centroid detection method, we have developed a digital SHWS system which can automatically detect centroids of focal spots, reconstruct the wavefront and measure the 3D profile of the surface. The system has been tested with various simulated and real surfaces such as flat surfaces, spherical and aspherical surfaces as well as deformable surfaces. The experimental results demonstrate that the system has good accuracy, repeatability and immunity to optical misalignment. The system is also suitable for on-line applications of surface measurement

  11. GPM and TRMM Radar Vertical Profiles and Impact on Large-scale Variations of Surface Rain

    Science.gov (United States)

    Wang, J. J.; Adler, R. F.

    2017-12-01

    Previous studies by the authors using Tropical Rainfall Measuring Mission (TRMM) and Global Precipitation Measurement (GPM) data have shown that TRMM Precipitation Radar (PR) and GPM Dual-Frequency Precipitation Radar (DPR) surface rain estimates do not have corresponding amplitudes of inter-annual variations over the tropical oceans as do passive microwave observations by TRMM Microwave Imager (TMI) and GPM Microwave Imager (GMI). This includes differences in surface temperature-rainfall variations. We re-investigate these relations with the new GPM Version 5 data with an emphasis on understanding these differences with respect to the DPR vertical profiles of reflectivity and rainfall and the associated convective and stratiform proportions. For the inter-annual variation of ocean rainfall from both passive microwave (TMI and GMI) and active microwave (PR and DPR) estimates, it is found that for stratiform rainfall both TMI-PR and GMI-DPR show very good correlation. However, the correlation of GMI-DPR is much higher than TMI-PR in convective rainfall. The analysis of vertical profile of PR and DPR rainfall during the TRMM and GPM overlap period (March-August, 2014) reveals that PR and DPR have about the same rainrate at 4km and above, but PR rainrate is more than 10% lower that of DPR at the surface. In other words, it seems that convective rainfall is better defined with DPR near surface. However, even though the DPR results agree better with the passive microwave results, there still is a significant difference, which may be a result of DPR retrieval error, or inherent passive/active retrieval differences. Monthly and instantaneous GMI and DPR data need to be analyzed in details to better understand the differences.

  12. Mercury cadmium telluride implanted junction profile measurement and depth control

    Science.gov (United States)

    Zhou, Songmin; Lin, Chun; Li, Haibin; Wei, Yanfeng; Ye, Zhenhua; Ding, Ruijun; He, Li

    2014-06-01

    In this work, a novel junction profile measurement method is proposed. A serial of junctions were fabricated by B+ implantation. Then a beveled bar which was about 10mm long and several micrometers deep was formed by carefully controlled wet-etching. The remaining depth of n region changes from the full depth that is about 5.3mm after ion implantation to zero depending on its lateral position and the slope of the etching bar. Voltage-current and Laser Beam Induced Current (LBIC) measurements were applied to determine the HgCdTe junction edge. The LBIC signal orrectification characteristic indicates the existence of a PN junction. The junction depth is extracted from the position where the PN junction disappears and the slope of the etching bar. The junction depth of intrinsic doped HgCdTe was measured, which is about 2.4μm. A significant 0.4mm thick N-region was observed. Moreover, junction depths of samples annealed for different time were also investigated. By this method, it's possible to measure the three dimensional profile of a planar PN junction.

  13. Surface antireflection properties of GaN nanostructures with various effective refractive index profiles.

    Science.gov (United States)

    Han, Lu; Zhao, Hongping

    2014-12-29

    GaN nanostructures with various effective refractive index profiles (Linear, Cubic, and Quintic functions) were numerically studied as broadband omnidirectional antireflection structures for concentrator photovoltaics by using three-dimensional finite difference time domain (3D-FDTD) method. Effective medium theory was used to design the surface structures corresponding to different refractive index profiles. Surface antireflection properties were calculated and analyzed for incident light with wavelength, polarization and angle dependences. The surface antireflection properties of GaN nanostructures based on six-sided pyramid with both uniform and non-uniform patterns were also investigated. Results indicate a significant dependence of the surface antireflection on the refractive index profiles of surface nanostructures as well as their pattern uniformity. The GaN nanostructures with linear refractive index profile show the best performance to be used as broadband omnidirectional antireflection structures.

  14. Mobile depth profiling and sub-surface imaging techniques for historical paintings—A review

    Energy Technology Data Exchange (ETDEWEB)

    Alfeld, Matthias, E-mail: matthias.alfeld@desy.de [University of Hamburg, Department of Chemistry, Martin-Luther-King Platz 6, D-20146 Hamburg (Germany); University of Antwerp, Department of Chemistry, Groenenbrogerlaan 171, B-2020 Antwerp (Belgium); Broekaert, José A.C., E-mail: jose.broekaert@chemie.uni-hamburg.de [University of Hamburg, Department of Chemistry, Martin-Luther-King Platz 6, D-20146 Hamburg (Germany)

    2013-10-01

    Hidden, sub-surface paint layers and features contain valuable information for the art-historical investigation of a painting's past and for its conservation for coming generations. The number of techniques available for the study of these features has been considerably extended in the last decades and established techniques have been refined. This review focuses on mobile non-destructive subsurface imaging and depth profiling techniques, which allow for the in-situ investigation of easel paintings, i.e. paintings on a portable support. Among the techniques discussed are: X-ray radiography and infrared reflectography, which are long established methods and are in use for several decades. Their capabilities of element/species specific imaging have been extended by the introduction of energy/wavelength resolved measurements. Scanning macro-X-ray fluorescence analysis made it for the first time possible to acquire elemental distribution images in-situ and optical coherence tomography allows for the non-destructive study the surface paint layers in virtual cross-sections. These techniques and their variants are presented next to other techniques, such as Terahertz imaging, Nuclear Magnetic Resonance depth profiling and established techniques for non destructive testing (thermography, ultrasonic imaging and laser based interference methods) applied in the conservation of historical paintings. Next to selected case studies the capabilities and limitations of the techniques are discussed. - Highlights: • All mobile sub-surface and depth-profiling techniques for paintings are reviewed. • The number of techniques available has increased considerably in the last years. • X-ray radiography and infrared reflectography are still the most used techniques. • Scanning macro-XRF and optical coherence tomography begin to establish. • Industrial non destructive testing techniques support the preservation of paintings.

  15. Water surface temperature profiles for the Rhine River derived from Landsat ETM+ data

    Science.gov (United States)

    Fricke, Katharina; Baschek, Björn

    2013-10-01

    Water temperature influences physical and chemical parameters of rivers and streams and is an important parameter for water quality. It is a crucial factor for the existence and the growth of animal and plant species in the river ecosystem. The aim of the research project "Remote sensing of water surface temperature" at the Federal Institute of Hydrology (BfG), Germany, is to supplement point measurements of water temperature with remote sensing methodology. The research area investigated here is the Upper and Middle Rhine River, where continuous measurements of water temperature are already available for several water quality monitoring stations. Satellite imagery is used to complement these point measurements and to generate longitudinal temperature profiles for a better systematic understanding of the changes in river temperature along its course. Several products for sea surface temperature derived from radiances in the thermal infrared are available, but for water temperature from rivers less research has been carried out. Problems arise from the characteristics of the river valley and morphology and the proximity to the riverbank. Depending on the river width, a certain spatial resolution of the satellite images is necessary to allow for an accurate identification of the river surface and the calculation of water temperature. The bands from the Landsat ETM+ sensor in the thermal infrared region offer a possibility to extract the river surface temperatures (RST) of a sufficiently wide river such as the Rhine. Additionally, problems such as cloud cover, shadowing effects, georeferencing errors, different emissivity of water and land, scattering of thermal radiation, adjacency and mixed pixel effects had to be accounted for and their effects on the radiance temperatures will be discussed. For this purpose, several temperature data sets derived from radiance and in situ measurements were com- pared. The observed radiance temperatures are strongly influenced by

  16. Analysis of Ozone And CO2 Profiles Measured At A Diary Facility

    Science.gov (United States)

    Ogunjemiyo, S. O.; Hasson, A. S.; Ashkan, S.; Steele, J.; Shelton, T.

    2015-12-01

    Ozone and carbon dioxide are both greenhouse gasses in the planetary boundary layer. Ozone is a harmful secondary pollutant in the troposphere produced mostly during the day when there is a photochemical reaction in which primary pollutant precursors such as nitrous oxide (NOx) or volatile organic compounds (VOC's) mix with sunlight. As with most pollutants in the lower troposphere, both ozone and carbon dioxide vary in spatial and temporal scale depending on sources of pollution, environmental conditions and the boundary layer dynamics. Among the several factors that influence ozone variation, the seasonal changes in meteorological parameters and availability of ozone precursors are crucial because they control ozone formation and decay. Understanding how the difference in emission sources affect vertical transport of ozone and carbon dioxide is considered crucial to the improvement of their regional inventory sources. The purpose of this study is to characterize vertical transport of ozone and carbon at a diary facility. The study was conducted in the summer of 2011 and 2012 at a commercial dairy facility in Central California and involved profile measurements of ozone and CO2 using electrochemical ozonesondes, meteorological sondes and CO2 probe tethered to a 9 cubic meters helium balloon. On each day of the data collection, multiple balloon launches were made over a period representing different stages of the boundary layer development. The results show ozone and CO2 profiles display different characteristics. Regardless of the time of the day, the CO2 concentration decreases with height with a sharp gradient near the surface that is strengthened by a stable atmospheric condition, a feature suggesting the surface as the source. On the other hand, ozone profiles show greater link to the evolution of the lower boundary layer. Ozone profiles display unique features indicating ozone destruction near the surface. This unusual near the surface, observed even in the

  17. Development of a new generation of optical slope measuring profiler

    Energy Technology Data Exchange (ETDEWEB)

    Yashchuk, Valeriy V.; Takacs, Peter Z.; McKinney, Wayne R.; Assoufid, Lahsen; Siewert, Frank; Zeschke, Thomas

    2010-09-16

    A collaboration, including all DOE synchrotron labs, industrial vendors of x-ray optics, and with active participation of the HBZ-BESSY-II optics group has been established to work together on a new slope measuring profiler -- the optical slope measuring system (OSMS). The slope measurement accuracy of the instrument is expected to be<50 nrad for the current and future metrology of x-ray optics for the next generation of light sources. The goals were to solidify a design that meets the needs of mirror specifications and also be affordable; and to create a common specification for fabrication of a multi-functional translation/scanning (MFTS) system for the OSMS. This was accomplished by two collaborative meetings at the ALS (March 26, 2010) and at the APS (May 6, 2010).

  18. Hamiltonian Evolution of Monokinetic Measures with Rough Momentum Profile

    KAUST Repository

    Bardos, Claude W.

    2014-12-27

    Consider a monokinetic probability measure on the phase space (Formula presented.) , i.e. (Formula presented.) where Uin is a vector field on RN and ρin a probability density on RN. Let Φt be a Hamiltonian flow on RN × RN. In this paper, we study the structure of the transported measure (Formula presented.) and of its integral in the ξ variable denoted ρ(t). In particular, we give estimates on the number of folds in (Formula presented.) , on which μ(t) is concentrated. We explain how our results can be applied to investigate the classical limit of the Schrödinger equation by using the formalism of Wigner measures. Our formalism includes initial momentum profiles Uin with much lower regularity than required by the WKB method. Finally, we discuss a few examples showing that our results are sharp.

  19. TCP Throughput Profiles Using Measurements over Dedicated Connections

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Nageswara S. [ORNL; Liu, Qiang [ORNL; Sen, Satyabrata [ORNL; Towsley, Don [University of Massachusetts, Amherst; Vardoyan, Gayane [University of Massachusetts, Amherst; Kettimuthu, R. [Argonne National Laboratory (ANL); Foster, Ian [University of Chicago

    2017-06-01

    Wide-area data transfers in high-performance computing infrastructures are increasingly being carried over dynamically provisioned dedicated network connections that provide high capacities with no competing traffic. We present extensive TCP throughput measurements and time traces over a suite of physical and emulated 10 Gbps connections with 0-366 ms round-trip times (RTTs). Contrary to the general expectation, they show significant statistical and temporal variations, in addition to the overall dependencies on the congestion control mechanism, buffer size, and the number of parallel streams. We analyze several throughput profiles that have highly desirable concave regions wherein the throughput decreases slowly with RTTs, in stark contrast to the convex profiles predicted by various TCP analytical models. We present a generic throughput model that abstracts the ramp-up and sustainment phases of TCP flows, which provides insights into qualitative trends observed in measurements across TCP variants: (i) slow-start followed by well-sustained throughput leads to concave regions; (ii) large buffers and multiple parallel streams expand the concave regions in addition to improving the throughput; and (iii) stable throughput dynamics, indicated by a smoother Poincare map and smaller Lyapunov exponents, lead to wider concave regions. These measurements and analytical results together enable us to select a TCP variant and its parameters for a given connection to achieve high throughput with statistical guarantees.

  20. Enzyme activity measurement via spectral evolution profiling and PARAFAC

    DEFF Research Database (Denmark)

    Baum, Andreas; Meyer, Anne S.; Garcia, Javier Lopez

    2013-01-01

    The recent advances in multi-way analysis provide new solutions to traditional enzyme activity assessment. In the present study enzyme activity has been determined by monitoring spectral changes of substrates and products in real time. The method relies on measurement of distinct spectral...... fingerprints of the reaction mixture at specific time points during the course of the whole enzyme catalyzed reaction and employs multi-way analysis to detect the spectral changes. The methodology is demonstrated by spectral evolution profiling of Fourier Transform Infrared (FTIR) spectral fingerprints using...

  1. High Resolution Shear Profile Measurements in Entangled Polymers

    KAUST Repository

    Hayes, Keesha A.

    2008-11-17

    We use confocal microscopy and particle image velocimetry to visualize motion of 250-300 nm. fluorescent tracer particles in entangled polymers subject to a rectilinear shear flow. Our results show linear velocity profiles in polymer solutions spanning a wide range of molecular weights and number of entanglements (8≤Z≤56), but reveal large differences between the imposed and measured shear rates. These findings disagree with recent reports that shear banding is a characteristic flow response of entangled polymers, and instead point to interfacial slip as an important source of strain loss. © 2008 The American Physical Society.

  2. Influence of veneer thickness on residual stress profile in veneering ceramic: measurement by hole-drilling.

    Science.gov (United States)

    Mainjot, Amélie K; Schajer, Gary S; Vanheusden, Alain J; Sadoun, Michaël J

    2012-02-01

    The veneering process of frameworks induces residual stresses and can initiate cracks when combined with functional stresses. The stress distribution within the veneering ceramic as a function of depth is a key factor influencing failure by chipping. This is a well-known problem with Yttria-tetragonal-zirconia-polycrystal based fixed partial dentures. The objective of this study is to investigate the influence of veneer thickness on the stress profile in zirconia- and metal-based structures. The hole-drilling method, often used for engineering measurements, was adapted for use with veneering ceramic. The stress profile was measured in bilayered disc samples of 20 mm diameter, with a 1 mm thick zirconia or metal framework. Different veneering ceramic thicknesses were performed: 1 mm, 1.5 mm, 2 mm, 2.5 mm and 3 mm. All samples exhibited the same type of stress vs. depth profile, starting with compressive at the ceramic surface, decreasing with depth up to 0.5-1.0 mm from the surface, and then becoming compressive again near the framework, except for the 1.5 mm-veneered zirconia samples which exhibited interior tensile stresses. Stresses in the surface of metal samples were not influenced by veneer thickness. Variation of interior stresses at 1.2 mm from the surface in function of veneer thickness was inverted for metal and zirconia samples. Veneer thickness influences in an opposite way the residual stress profile in metal- and in zirconia-based structures. A three-step approach and the hypothesis of the crystalline transformation are discussed to explain the less favorable residual stress development in zirconia samples. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  3. [Measuring microhardness of laser exposed tooth surface].

    Science.gov (United States)

    Florin, R; Herrmann, C; Bernhardt, W

    1990-02-01

    In principle it is possible to homogenize the enamel surface by melting structural elements with the continuous wave CO2 laser. Using the precision instrument NEOPHOT 2 (Carl Zeiss JENA) the microhardness of extracted laserexposed premolares were tested so as to clarify the functional strain capasity and the mechanical characteristics of laserexposed regions of enamel surfaces. The proven higher hardness in the centre of the laserinduced fusing zones (in comparison with adjacent enamel) objectify an attainable refining of the enamel surface that probably causes an increase in the caries-preventive resistance.

  4. Validation of Suomi NPP OMPS Limb Profiler Ozone Measurements

    Science.gov (United States)

    Buckner, S. N.; Flynn, L. E.; McCormick, M. P.; Anderson, J.

    2017-12-01

    The Ozone Mapping and Profiler Suite (OMPS) Limb Profiler onboard the Suomi National Polar-Orbiting Partnership satellite (SNPP) makes measurements of limb-scattered solar radiances over Ultraviolet and Visible wavelengths. These measurements are used in retrieval algorithms to create high vertical resolution ozone profiles, helping monitor the evolution of the atmospheric ozone layer. NOAA is in the process of implementing these algorithms to make near-real-time versions of these products. The main objective of this project is to generate estimates of the accuracy and precision of the OMPS Limb products by analysis of matchup comparisons with similar products from the Earth Observing System Microwave Limb Sounder (EOS Aura MLS). The studies investigated the sources of errors, and classified them with respect to height, geographic location, and atmospheric and observation conditions. In addition, this project included working with the algorithm developers in an attempt to develop corrections and adjustments. Collocation and zonal mean comparisons were made and statistics were gathered on both a daily and monthly basis encompassing the entire OMPS data record. This validation effort of the OMPS-LP data will be used to help validate data from the Stratosphere Aerosol and Gas Experiment III on the International Space Station (SAGE III ISS) and will also be used in conjunction with the NOAA Total Ozone from Assimilation of Stratosphere and Troposphere (TOAST) product to develop a new a-priori for the NOAA Unique Combined Atmosphere Processing System (NUCAPS) ozone product. The current NUCAPS ozone product uses a combination of Cross-track Infrared Sounder (CrIS) data for the troposphere and a tropopause based climatology derived from ozonesonde data for the stratosphere a-priori. The latest version of TOAST uses a combination of both CrIS and OMPS-LP data. We will further develop the newest version of TOAST and incorporate it into the NUCAPS system as a new a

  5. CONTACT ANGLE MEASUREMENT OF DENTAL RESTORATIVE MATERIALS BY DROP PROFILE IMAGE ANALYSIS

    Directory of Open Access Journals (Sweden)

    H. D. K. Yulianto dan M. Rinastiti

    2014-06-01

    Full Text Available The capability of initial microbial adhesion to dental restorative composites surface is influenced by the surface wettability of the materials. The common method to evaluate surface wettability of materials is contact angle measurement. The existing conventional method to measure contact angle is by means of a contact angle (CA-Goniometer device, which is less practically applicable in clinical circumstances. Therefore, a more practical and applicable method is needed to measure contact angle in clinical circumstances. This research was performed to compare between contact angles measured by means of a CA-Goniometer device and a new practical method of drop profile image analysis. In addition, since there were two different formulas that can be used to calculate contact angle value from a drop profile image, then we also need to evaluate which formula is more reliable to be used. Tests were carried out using three composite discs (Clearfill-Kuraray Medical, Inc. sample and deionised water for different measurement procedures. One drop of 3µl liquid was dropped onto the surface of the composite discs, and the drop profile image was captured by means of a customized home-made device connected to a digital camera. Two different formulas were used to calculate the contact angle value from the drop profile image, namely the “linier gradient equation” and the “tangential line”. The contact angle values obtained from the two different formulas were compared with the value obtained from the conventional method descriptively. Tests were carried out using three composite discs (Clearfill-Kuraray Medical, Inc. sample and deionised water for different measurement procedures. One drop of 3µl liquid was dropped onto the surface of the composite discs, and the drop profile image was captured by means of a customized home-made device connected to a digital camera. Two different formulas were used to calculate the contact angle value from the drop

  6. Experimental measurements of the detonation wave profile in a TATB based explosive

    Directory of Open Access Journals (Sweden)

    Decaris L.

    2011-01-01

    Full Text Available We report results of the experimental measurements of the detonation wave profile of the TATB based plastic bonded explosive T2 (97 w. % of TATB using VISAR and Heterodyne Velocimetry (HV – same as Photon Doppler Velocimetry. The experiment consists in initiating a detonation wave in a 15 mm diameter cylinder of explosive using an explosive wire detonator and an explosive booster. In order to obtain the particle velocity history in the reaction zone, we measure particle velocity at the interaction of the detonation front with an aluminized window or the free surface velocity of a metallic foil. Lithium Fluoride (LIF, PMMA and steel have been tested. Several shots have been performed for different lengths of explosive. We compare the VISAR and HV measurements. With LIF and steel, VISAR and HV diagnostics give very similar profiles. The ZND profile obtained on LIF is resolved with both techniques. With PMMA, HV gives a more accurate profile than VISAR in the reaction zone. There is no evidence of the influence of the explosive cylinder length.

  7. Residual Gas Fluorescence for Profile Measurements at the GSI UNILAC

    CERN Document Server

    Forck, P

    2002-01-01

    The high beam currents, delivered at the LINAC at GSI (UNILAC) can destroy intercepting diagnostics within one macro-pulse. As an alternative for a non-destructive profile measurement the methode for residual-gas-fluorescence is investigated. The fluorescence light is emitted by the N2 molecules of the residual gas at the blue wavelength range and can be monitored with a modern CCD-camera. The images are transferred via digital bus (IEEE 1394 'FireWire') and the profiles are generated by analysis of the images with a modern software tool (National Instruments 'LabView'). Due to the short beam pulses (about 0.2 ms) the light intensities emitted by the residual gas are low and require a high amplification (gain >106) which is realized with an image intensifier with double MCP (multi channel plate), connected with a fiber taper to the CCD-chip. The design parameters of the optics and electronics are discussed as well as the advantages of the digital data transmission. Measurements with heavy ion beams of several...

  8. Surface texturing of crystalline silicon and effective area measurement

    Science.gov (United States)

    Sun, Tietun; Chen, Dong; Chui, Rongqiang

    2000-11-01

    In this paper, the surface area of solar cell is determined by the capacitance measurements of MOS structure. The texture etching technology can be controlled according to the change of silicon surface area, furthermore, the textured silicon surface and interface characteristic of solar cell can be studied by measuring the relationship of capacitance and voltage for MOS structure.

  9. Deep learning for galaxy surface brightness profile fitting

    Science.gov (United States)

    Tuccillo, D.; Huertas-Company, M.; Decencière, E.; Velasco-Forero, S.; Domínguez Sánchez, H.; Dimauro, P.

    2018-03-01

    Numerous ongoing and future large area surveys (e.g. Dark Energy Survey, EUCLID, Large Synoptic Survey Telescope, Wide Field Infrared Survey Telescope) will increase by several orders of magnitude the volume of data that can be exploited for galaxy morphology studies. The full potential of these surveys can be unlocked only with the development of automated, fast, and reliable analysis methods. In this paper, we present DeepLeGATo, a new method for 2-D photometric galaxy profile modelling, based on convolutional neural networks. Our code is trained and validated on analytic profiles (HST/CANDELS F160W filter) and it is able to retrieve the full set of parameters of one-component Sérsic models: total magnitude, effective radius, Sérsic index, and axis ratio. We show detailed comparisons between our code and GALFIT. On simulated data, our method is more accurate than GALFIT and ˜3000 time faster on GPU (˜50 times when running on the same CPU). On real data, DeepLeGATo trained on simulations behaves similarly to GALFIT on isolated galaxies. With a fast domain adaptation step made with the 0.1-0.8 per cent the size of the training set, our code is easily capable to reproduce the results obtained with GALFIT even on crowded regions. DeepLeGATo does not require any human intervention beyond the training step, rendering it much automated than traditional profiling methods. The development of this method for more complex models (two-component galaxies, variable point spread function, dense sky regions) could constitute a fundamental tool in the era of big data in astronomy.

  10. Seasonality in onshore normalized wind profiles above the surface layer

    DEFF Research Database (Denmark)

    Nissen, Jesper Nielsen; Gryning, Sven-Erik

    2010-01-01

    This work aims to study the seasonal difference in normalized wind speed above the surface layer as it is observed at the 160 m high mast at the coastal site Høvsøre at winds from the sea (westerly). Normalized and stability averaged wind speeds above the surface layer are observed to be 20 to 50......% larger in the winter/spring seasons compared to the summer/autumn seasons at winds from west within the same atmospheric stability class. A method combining the mesoscale model, COAMPS, and observations of the surface stability of the marine boundary layer is presented. The objective of the method...... is to reconstruct the seasonal signal in normalized wind speed and identify the physical process behind. The method proved reasonably successful in capturing the relative difference in wind speed between seasons, indicating that the simulated physical processes are likely candidates to the observed seasonal signal...

  11. High-resolution surface temperature measurements on rotating turbine blades with an infrared pyrometer

    Science.gov (United States)

    Uguccini, O. W.; Pollack, F. G.

    1976-01-01

    A high-resolution pyrometer was developed and tested on a modified turbine engine. The pyrometer was used to obtain temperature profiles of the viewed surface of turbine blades in the engine at tip speeds up to 366 meters per second. The combination of coherent fiber optics, a silicon avalanche detector, and high-speed electronics enabled surface resolution of a spot diameter of 0.05 centimeter. The data, in the form of temperature profiles, was obtained in near real time as a hard copy output from a computer display terminal. Temperatures measured with the pyrometer and with thermocouples agreed within 2 percent at temperatures between 977 to 1144 K.

  12. Optimization for sinusoidal profiles in surface relief gratings ...

    Indian Academy of Sciences (India)

    2014-02-07

    Feb 7, 2014 ... ometric pattern in photosensitive materials such as photoresists and many other types of photopolymers that are capable of generating surface relief structures. Indigenous devel- opment of such diffraction gratings has been taken up in our department for laser and spectroscopic applications. The purpose ...

  13. High speed machined surface roughness measurement ...

    African Journals Online (AJOL)

    Surface roughness monitoring techniques using non-contact methods based on computer vision technology are becoming popular and cost effective. An evolvable hardware configuration using reconfigurable Xilinx Virtex FPGA xcv1000 architecture with capability to compensate for poor illumination environment is ...

  14. Surface density profile and surface tension of the one-component classical plasma

    International Nuclear Information System (INIS)

    Ballone, P.; Senatore, G.; Trieste Univ.; Tosi, M.P.; Oxford Univ.

    1982-08-01

    The density profile and the interfacial tension of two classical plasmas in equilibrium at different densities are evaluated in the square-density-gradient approximation. For equilibrium in the absence of applied external voltage, the profile is oscillatory in the higher-density plasma and the interfacial tension is positive. The amplitude and phase of these oscillations and the magnitude of the interfacial tension are related to the width of the background profile. Approximate representations of the equilibrium profile by matching of its asymptotic forms are analyzed. A comparison with computer simulation data and a critical discussion of a local-density theory are also presented. (author)

  15. Flatness of two-dimensional beam profile measured with an ionization chamber array

    International Nuclear Information System (INIS)

    Stefanovski, Z.

    2006-01-01

    Open beam profiles are basic dosimetric characteristics for the formation of the dose calculation algorithms parameters and for determination of beam quality. One characteristic of the beam profiles as a measure for the beam quality is the field flatness defined as ratio of the difference of maximum and minimum dose in central 80% of the field to the sum of these doses in the part of the field. The measurements, instead with an ordinary ionization chamber, were performed with a chamber array in two depths (1.6 cm and 10 cm) in water phantom. Nominal photon beam energy was 6 MV and field size was 25 cm x 25 cm on the water surface. Field flatness was in the range of 1-2 % which is in accordance with the data acquired during the acceptance testing and commissioning of the accelerators. with the array chamber the beam profiles can be performed quickly and preciously. These features recommend a chamber array as an excellent tool for periodic quality control of beam profiles. (Author)

  16. 3D Surface Profile and Color Stability of Tooth Colored Filling Materials after Bleaching

    Directory of Open Access Journals (Sweden)

    Bryant Anthony Irawan

    2015-01-01

    Full Text Available This study aims to evaluate the effects of vital tooth bleaching with carbamide peroxide home bleaching and in-office bleaching on the color stability and 3D surface profile of dental restorative filling materials. Thirty discs (n=30 measure 6 mm in diameter and 2 mm thick for each of three restorative materials. These are nanofilled composite Filtek Z350 XT, the submicron composite Estelite Σ Quick, and nanofilled glass ionomer Ketac N100 nanoionomer and were fabricated in shade A2. Each group was further divided into three subgroups (n=10: subgroup A (Opalescence PF, subgroup B (Opalescence Boost in-office bleaching, and subgroup C (distilled water serving as control. Samples were bleached according to the manufacturer’s instructions for a period of two weeks. The Commission Internationale de L’Eclairage (CIE L*, a*, b* system was chosen for image processing, while 3D surface profile was tested with atomic force microscopy (AFM. Statistical analyses were performed with the Mann-Whitney tests and Krusal-Wallis with a P value of ≤0.05. The three restorative materials showed significant color changes (ΔE; P≤0.05. In diminishing order, the mean color changes recorded were Estelite Σ (3.82 ± 1.6 > Ketac Nano (2.97 ± 1.2 > Filtek Z350 XT (2.25 ± 1.0. However, none of the tested materials showed statistically significant changes in surface roughness; P>0.05.

  17. Surface profiling in mating parts by combined nonabrasive finishing

    Science.gov (United States)

    Smolentsev, EV; Fedonin, ON; Smolentsev, VP

    2017-02-01

    Nonabrasive finishing of precision mating surfaces in locking devices with the use of a combined erosion-chemical process at the first stage of the processing and with the use of anodic dissolution by alternating low-voltage current at the final stage of a refinement operation till gapless joints obtaining is considered. It is shown that the application of electro-erosion, electrochemical and combined nonabrasive finishing in mating parts opens up a possibility to ensure stable impermeability in locking devices on a macro- and micro-level through the method of a substantiated purpose of technological modes. A procedure is created for the development of such modes, and on their basis technological processes for the obtaining of gapless mating surfaces meeting the performance requirements for locking devices are developed. For this purpose, qualitative devices resistant to hostile environment are manufactured that is urgent for the mechanical engineering including repetition work for the equipment of petrochemical industry, transport and household machinery.

  18. Microthermal Instrument for Measuring Surface Layer Seeing

    Science.gov (United States)

    Li, Xue-Bao; Zheng, Yan-Fang; Deng, Lin Hua; Xu, Guang

    2012-02-01

    Microthermal fluctuations are introduced by atmospheric turbulence very near the ground. In order to detect microthermal fluctuations at Fuxian Solar Observatory (FSO), a microthermal instrument has been developed. The microthermal instrument consists of a microthermal sensor, which is based on a Wheatstone bridge circuit and uses fine tungsten filaments as resistance temperature detectors, an associated signal processing unit, and a data collection, & communication subsystem. In this paper, after a brief introduction to surface layer seeing, we discuss the instrumentation behind the microthermal detector we have developed and then present the results obtained. The results of the evaluation indicate that the effect of the turbulent surface boundary layer to astronomical seeing would become sufficiently small when installing a telescope at a height of 16m or higher from the ground at FSO.

  19. Rivited panel surface measurement using photogrammetry

    Science.gov (United States)

    Merrick, W. D.; Lobb, V. B.; Lansing, F. L.; Stoller, F. W.

    1986-01-01

    Two riveted antenna panels on rings number 3 and 9 were removed from the 34m antenna at DSS-15, fixed in the leveled position and the surface was photographed indoors. The results from this pilot photogrammetric demonstration and diagnostics of panel surface contours, are presented. The photogrammetric network for each panel incorporated eight photographs, two from each of four camera stations and observed over 200 targets. The accuracy (1 sigma) of the XYZ coordinates for the error ellipsoids was + or - 0.013 mm (0.0005 inch). This level of precision relative to the object size corresponds roughly to 1 part in 250,000 which is superior to conventional dial sweep-arm template techniques by at least a factor of 4.

  20. Surface Temperature Measurement Using Hematite Coating

    Science.gov (United States)

    Bencic, Timothy J. (Inventor)

    2015-01-01

    Systems and methods that are capable of measuring temperature via spectrophotometry principles are discussed herein. These systems and methods are based on the temperature dependence of the reflection spectrum of hematite. Light reflected from these sensors can be measured to determine a temperature, based on changes in the reflection spectrum discussed herein.

  1. Comparison of mixing height parameterizations with profiles measurements

    Energy Technology Data Exchange (ETDEWEB)

    Jaquier, A.; Stuebi, R.; Tercier, P. [Swiss Meteorological Inst., SMI - MeteoSwiss, Payerne (Switzerland)

    1997-10-01

    Different meteorological pre-processors for dispersion studies are available to derive the atmospheric boundary layer mixing height (MH). The analysis of their performances has been reviewed in the framework of the European COST Action 710. In this project, the computed mixing height values have been compared with data derived mostly from aero-logical sounding analysis and Sodar measurements. Since then, a new analysis of a low-tropospheric wind profiler (WP) data has been performed taking advantage of its high data sampling ({delta}t {approx} 30 sec.). The comparison between these recent results and aero-logical sounding, Sodar data, as well as to meteorological pre-processors calculations are reported for three periods of several days corresponding to different meteorological situations. In convective conditions, the pre-processors give reasonable level, the mixing height growing rate is in fair agreement with the measured one. In stable cloudy daytime conditions, the modeled mixing height does not correspond to any measured height. (LN)

  2. Risø 1978: Further Investigations into the Effects of Local Terrain Irregularties on Tower-Measured Wind Profiles

    DEFF Research Database (Denmark)

    Peterson, E. W.; Taylor, P. A.; Højstrup, Jørgen

    1980-01-01

    Observations of flow over complex terrain taken at Risø during June–July 1978 and numerical studies confirm earlier findings that small variations in surface elevation have significant effects on mean wind profiles. Measured shear stresses in the nonequilibrium region of the flow are consistent w...

  3. Time resolved temperature measurement of polymer surface irradiated by mid-IR free electron laser

    Science.gov (United States)

    Araki, Mitsunori; Chiba, Tomoyuki; Oyama, Takahiro; Imai, Takayuki; Tsukiyama, Koichi

    2017-08-01

    We have developed the time-resolved temperature measurement system by using a radiation thermometer FLIR SC620. Temporal temperature profiles of an acrylic resin surface by the irradiation of infrared free electron laser (FEL) pulse were recorded in an 8 ms resolution to measure an instantaneous temperature rise and decay profile. Under the single-shot condition, a peak temperature defined as the temperature jump from the ambient temperature was found to be proportional to the absorbance. Under the multi-shot condition, the temperature accumulation was found to reach a roughly constant value where the supply and release of the heat is balanced.

  4. Infrared pyrometer for high resolution surface temperature measurements on rotating turbine blades

    Science.gov (United States)

    Uguccini, O. W.

    1976-01-01

    A high resolution pyrometer was developed and used to obtain temperature profiles of rotating turbine blades at tip speeds up to 366 meters per second (1200 fps). Surface temperature variations from 920 to 1250 K (1200 to 1800 F) can be measured and variations over distances of 0.05 cm (0.020 in.) can be resolved. Temperature profiles were obtained in near real time as hard copies from a computer display terminal. Temperatures measured with the prototype pyrometer and with thermocouples agreed to within 2 percent over the temperature range from 977 to 1144 K (1300 to 1600 F).

  5. Infrared pyrometer for high resolution surface temperature measurement on rotating turbine blades

    Science.gov (United States)

    Uguccini, O. W.

    1976-01-01

    A high resolution pyrometer was developed and used to obtain temperature profiles of rotating turbine blades at tip speeds up to 366 meters per second. Surface temperature variations from 920 to 1250 K can be measured and variations over distances of 0.05 cm can be resolved. Temperature profiles were obtained in near real time as hard copies from a computer display terminal. Temperatures measured with the prototype pyrometer and with thermocouples agreed to within 2 percent over the temperature range from 977 to 1144.

  6. Influence of the topography of the surface of the Earth on vertical sounding of the temperature profile

    Directory of Open Access Journals (Sweden)

    A. Pfister

    Full Text Available Atmospheric temperature and humidity fields as well as information on other meteorological parameters are nowadays retrieved from radiance measurements recorded by operational meteorological satellites. Up to now, the inversion procedures used only take into account crude information on the topography of the Earth's surface. However, the applied radiative transfer codes have to consider the Earth's surface as the lower boundary of the atmospheric model and, therefore, need a more precise mean elevation and a classification of the roughness of the Earth's surface. The influence of the topography of the Earth surface on retrieved temperature profiles is studied by using a physico-statistical inversion method. An objective analysis is made of the more precise mean elevation and derivation of roughness parameters using a new high-resolution digital elevation model (DEM with a resolution of 500 m×500 m. By means of a geomorphological process and a newly developed topography rejection test, areas with a high surface roughness are localized and singled out. The influence of topography on the retrieved temperature profiles is illustrated by case studies. Changes are found predominantly in areas with a high variation of topography. Using the new high-resolution DEM and the topography rejection test, the geographical position of the calculated temperature profiles tends to be shifted towards areas with a small vertical variation of topography. The mean elevation determined by the new elevation model better characterizes the area observed. Hence, the temperature profiles can be calculated down to lower atmospheric levels. Furthermore, a guess profile better describing the atmospheric situation is selected by the more precise elevation. In addition, the temperature profiles obtained near the coast are improved considerably by the more precise determination of the surface property `sea' and `land,' respectively. Integration of an

  7. Influence of the topography of the surface of the Earth on vertical sounding of the temperature profile

    Directory of Open Access Journals (Sweden)

    A. Pfister

    1995-03-01

    Full Text Available Atmospheric temperature and humidity fields as well as information on other meteorological parameters are nowadays retrieved from radiance measurements recorded by operational meteorological satellites. Up to now, the inversion procedures used only take into account crude information on the topography of the Earth's surface. However, the applied radiative transfer codes have to consider the Earth's surface as the lower boundary of the atmospheric model and, therefore, need a more precise mean elevation and a classification of the roughness of the Earth's surface. The influence of the topography of the Earth surface on retrieved temperature profiles is studied by using a physico-statistical inversion method. An objective analysis is made of the more precise mean elevation and derivation of roughness parameters using a new high-resolution digital elevation model (DEM with a resolution of 500 m×500 m. By means of a geomorphological process and a newly developed topography rejection test, areas with a high surface roughness are localized and singled out. The influence of topography on the retrieved temperature profiles is illustrated by case studies. Changes are found predominantly in areas with a high variation of topography. Using the new high-resolution DEM and the topography rejection test, the geographical position of the calculated temperature profiles tends to be shifted towards areas with a small vertical variation of topography. The mean elevation determined by the new elevation model better characterizes the area observed. Hence, the temperature profiles can be calculated down to lower atmospheric levels. Furthermore, a guess profile better describing the atmospheric situation is selected by the more precise elevation. In addition, the temperature profiles obtained near the coast are improved considerably by the more precise determination of the surface property `sea' and `land,' respectively. Integration of an independent physical

  8. Micro-PIV and CFD characterization of flows in a microchannel: Velocity profiles, surface roughness and Poiseuille numbers

    International Nuclear Information System (INIS)

    Silva, Goncalo; Leal, Nuno; Semiao, Viriato

    2008-01-01

    Microfluidics is a promising technology, although the governing physical mechanisms are still not quite understood due to the difficulties arising in measuring at such small scales. This work intends to bring some insight on the influence of surface phenomena in microscale flows by proposing a different method to quantify such influence. In this new method, detailed velocity measurements are performed to evaluate the influence on the flow of the surface phenomena instead of using measured bulk flow properties. For that micro-Particle Image Velocimetry (micro-PIV) is used to characterize the flow kinematics inside a DantecDynamics microchannel (with hydraulic diameter of 637 μm) that possesses rather rough walls (relative roughness of 1.6%) and a very irregular cross-section shape. Two-dimensional velocity profiles were measured in 61 horizontal planes to define the three-dimensional laminar flows (Re ≤ 50). Integration of the velocity profiles yielded volumetric flow rates with a maximum deviation of 3% from the measured volume of fluid discharged as function of time, which gives the magnitude of the bias error of the experimental technique. Effects of walls roughness were quantified by comparing Poiseuille numbers obtained from experimental velocity profiles against those obtained from CFD predictions for the same operating conditions but with hydrodynamically smooth walls, according to the new method proposed herein. Those Poiseuille numbers differed 11% demonstrating the need to account for wall roughness in microflows

  9. Computer vision for shoe upper profile measurement via upper and sole conformal matching

    Science.gov (United States)

    Hu, Zhongxu; Bicker, Robert; Taylor, Paul; Marshall, Chris

    2007-01-01

    This paper describes a structured light computer vision system applied to the measurement of the 3D profile of shoe uppers. The trajectory obtained is used to guide an industrial robot for automatic edge roughing around the contour of the shoe upper so that the bonding strength can be improved. Due to the specific contour and unevenness of the shoe upper, even if the 3D profile is obtained using computer vision, it is still difficult to reliably define the roughing path around the shape. However, the shape of the corresponding shoe sole is better defined, and it is much easier to measure the edge using computer vision. Therefore, a feasible strategy is to measure both the upper and sole profiles, and then align and fit the sole contour to the upper, in order to obtain the best fit. The trajectory of the edge of the desired roughing path is calculated and is then smoothed and interpolated using NURBS curves to guide an industrial robot for shoe upper surface removal; experiments show robust and consistent results. An outline description of the structured light vision system is given here, along with the calibration techniques used.

  10. The Mathematical Representation of Wind Speed and Temperature Profiles in the Unstable Atmospheric Surface Layer

    DEFF Research Database (Denmark)

    Paulson, C.A.

    1970-01-01

    Analytical expressions which specify non-dimensionalized wind speed and potential temperature gradients as functions of stability are integrated. The integrated equations are tested against Swinhank's wind and temperature profiles measured at Kerang, Australia. It is found that a representation...... suggested independently by Businger and by Dyer gives the best fit to temperature profiles and describes the wind profiles equally as well as a relation suggested by Panofsky et al....

  11. Clustering-driven residue filter for profile measurement system.

    Science.gov (United States)

    Jiang, Jun; Cheng, Jun; Zhou, Ying; Chen, Guang

    2011-02-01

    The profile measurement system is widely used in industrial quality control, and phase unwrapping (PU) is a key technique. An algorithm-driven PU is often used to reduce the impact of noise-induced residues to retrieve the most reliable solution. However, measuring speed is lowered due to the searching of optimal integration paths or correcting of phase gradients. From the viewpoint of the rapidity of the system, this paper characterizes the noise-induced residues, and it proposes a clustering-driven residue filter based on a set of directional windows. The proposed procedure makes the wrapped phases included in the filtering window have more similar values, and it groups the correct and noisy phases into individual clusters along the local fringe direction adaptively. It is effective for the tightly packed fringes, and it converts the algorithm-driven PU to the residue-filtering-driven one. This improves the operating speed of the 3D reconstruction significantly. The tests performed on simulated and real projected fringes confirm the validity of our approach.

  12. Predicting fiber refractive index from a measured preform index profile

    Science.gov (United States)

    Kiiveri, P.; Koponen, J.; Harra, J.; Novotny, S.; Husu, H.; Ihalainen, H.; Kokki, T.; Aallos, V.; Kimmelma, O.; Paul, J.

    2018-02-01

    When producing fiber lasers and amplifiers, silica glass compositions consisting of three to six different materials are needed. Due to the varying needs of different applications, substantial number of different glass compositions are used in the active fiber structures. Often it is not possible to find material parameters for theoretical models to estimate thermal and mechanical properties of those glass compositions. This makes it challenging to predict accurately fiber core refractive index values, even if the preform index profile is measured. Usually the desired fiber refractive index value is achieved experimentally, which is expensive. To overcome this problem, we analyzed statistically the changes between the measured preform and fiber index values. We searched for correlations that would help to predict the Δn-value change from preform to fiber in a situation where we don't know the values of the glass material parameters that define the change. Our index change models were built using the data collected from preforms and fibers made by the Direct Nanoparticle Deposition (DND) technology.

  13. Downhole temperature tool accurately measures well bore profile

    International Nuclear Information System (INIS)

    Cloud, W.B.

    1992-01-01

    This paper reports that an inexpensive temperature tool provides accurate temperatures measurements during drilling operations for better design of cement jobs, workovers, well stimulation, and well bore hydraulics. Valid temperature data during specific wellbore operations can improve initial job design, fluid testing, and slurry placement, ultimately enhancing well bore performance. This improvement applies to cement slurries, breaker activation for slurries, breaker activation for stimulation and profile control, and fluid rheological properties for all downhole operations. The temperature tool has been run standalone mounted inside drill pipe, on slick wire line and braided cable, and as a free-falltool. It has also been run piggyback on both directional surveys (slick line and free-fall) and standard logging runs. This temperature measuring system has been used extensively in field well bores to depths of 20,000 ft. The temperature tool is completely reusable in the field, ever similar to the standard directional survey tools used on may drilling rigs. The system includes a small, rugged, programmable temperature sensor, a standard body housing, various adapters for specific applications, and a personal computer (PC) interface

  14. Surface Gradient Integrated Profiler for X-ray and EUV Optics--Calibration of the rotational angle error of the rotary encoders

    International Nuclear Information System (INIS)

    Higashi, Yasuo; Kume, Tatsuya; Enami, Kazuhiro; Ueno, Kenji; Mori, Yuzo; Takaie, Yuichi; Endo, Katsuyoshi; Yamauchi, Kazuto; Yamamura, Kazuya; Sano, Yasuhisa

    2007-01-01

    A new ultraprecision profiler has been developed to measure for example asymmetric and aspheric profiles. The principle of our measuring method is that the normal vector at each point on the surface is determined by making the incident light beam on the mirror surface and the reflected beam at that point coincident. The gradient at each point is calculated from the normal vector, and the surface profile is then obtained by integrating the gradients. The measuring instrument was designed in accordance with the above principle for the measuring method and is called Surface Gradient Integrated Profiler (SGIP). In the design, four ultraprecision goniometers were applied to adjust the light axis for the normal vector measurement. These goniostages make it possible to attain an angular resolution of 0.018 μ radian by electrically dividing a pulse of the rotary encoder. The surface gradients are determined only by the rotational angle of goniometers. Thus in the measuring instrument, the most important factor is the accuracy of the normal vectors measured by the goniometers. To attain an accuracy of 0.1 μ radian, we developed a system for correcting the rotational angle error of the goniometers in which the trigonometric measuring method is utilized for geometrical angle determination

  15. High-Resolution Vertical Profile Measurements for Carbon Dioxide and Water Vapour Concentrations Within and Above Crop Canopies

    Science.gov (United States)

    Ney, Patrizia; Graf, Alexander

    2018-03-01

    We present a portable elevator-based facility for measuring CO2, water vapour, temperature and wind-speed profiles between the soil surface and the atmospheric surface layer above crop canopies. The end of a tube connected to a closed-path gas analyzer is continuously moved up and down over the profile range (in our case, approximately 2 m) while concentrations are logged at a frequency of 20 s^{-1}. Using campaign measurements in winter wheat, winter barley and a catch crop mixture (spring 2015 to autumn 2016) during different stages of crop development and different times of the day, we demonstrate a simple approach to correct for time lags, and the resulting profiles of 30-min mean mole fractions of CO2 and H2O over height increments of 0.025 m. The profiles clearly show the effects of soil respiration and photosynthetic carbon assimilation, varying both during the diurnal cycle and during the growing season. Profiles of temperature and wind speed are based on a ventilated finewire thermocouple and a hot-wire anemometer, respectively. Measurements over bare soil and a short plant canopy were analyzed in the framework of Monin-Obukhov similarity theory to check the validity of the measurements and raw-data-processing approach. Derived fluxes of CO2, latent and sensible heat and momentum show good agreement with eddy-covariance measurements.

  16. Oxygen accumulation on metal surfaces investigated by XPS, AES and LEIS, an issue for sputter depth profiling under UHV conditions

    Energy Technology Data Exchange (ETDEWEB)

    Steinberger, R., E-mail: roland.steinberger@jku.at [Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); Celedón, C.E., E-mail: carlos.celedon@usm.cl [Institut für Experimentalphysik, Abteilung für Atom- und Oberflächenphysik, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); Departamento de Física, Universidad Técnica Federico Santa María, Valaparaíso, Casilla 110-V (Chile); Bruckner, B., E-mail: barbara.bruckner@jku.at [Institut für Experimentalphysik, Abteilung für Atom- und Oberflächenphysik, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); Roth, D., E-mail: dietmar.roth@jku.at [Institut für Experimentalphysik, Abteilung für Atom- und Oberflächenphysik, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); Duchoslav, J., E-mail: jiri.duchoslav@jku.at [Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); Arndt, M., E-mail: martin.arndt@voestalpine.com [voestalpine Stahl GmbH, voestalpine-Straße 3, 4031 Linz (Austria); Kürnsteiner, P., E-mail: p.kuernsteiner@mpie.de [Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); and others

    2017-07-31

    Highlights: • Investigation on the impact of residual gas prevailing in UHV chambers. • For some metals detrimental oxygen uptake could be observed within shortest time. • Totally different behavior was found: no changes, solely adsorption and oxidation. • The UHV residual gas may severely corrupt results obtained from depth profiling. • A well-considered data acquisition sequence is the key for reliable depth profiles. - Abstract: Depth profiling using surface sensitive analysis methods in combination with sputter ion etching is a common procedure for thorough material investigations, where clean surfaces free of any contamination are essential. Hence, surface analytic studies are mostly performed under ultra-high vacuum (UHV) conditions, but the cleanness of such UHV environments is usually overrated. Consequently, the current study highlights the in principle known impact of the residual gas on metal surfaces (Fe, Mg, Al, Cr and Zn) for various surface analytics methods, like X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and low-energy ion scattering (LEIS). The investigations with modern, state-of-the-art equipment showed different behaviors for the metal surfaces in UHV during acquisition: (i) no impact for Zn, even after long time, (ii) solely adsorption of oxygen for Fe, slight and slow changes for Cr and (iii) adsorption accompanied by oxide formation for Al and Mg. The efficiency of different counter measures was tested and the acquired knowledge was finally used for ZnMgAl coated steel to obtain accurate depth profiles, which exhibited before serious artifacts when data acquisition was performed in an inconsiderate way.

  17. Offshore wind profiling using light detection and ranging measurements

    DEFF Research Database (Denmark)

    Pena Diaz, Alfredo; Hasager, Charlotte Bay; Gryning, Sven-Erik

    2009-01-01

    The advantages and limitations of the ZephlR (R), a continuous-wave, focused light detection and ranging (LiDAR) wind profiler, to observe offshore winds and turbulence characteristics were tested during a 6 month campaign at the tronsformer/platform of Hams Rev, the world's largest wind form....... The LiDAR system is a ground-based sensing technique which avoids the use of high and costly meteorological masts. Three different inflow conditions were selected to perform LiDAR wind profiling. Comparisons of LiDAR mean wind speeds against cup anemometers from different masts showed high correlations...... for the open sea sectors and good agreement with their longitudinal turbulence characteristics. Cup anemometer mean wind speed profiles were extended with LiDAR profiles up to 161 m on each inflow sector. The extension resulted in a good profile match for the three surrounding masts. These extended profiles...

  18. Radioactivity Measurements on Glazed Ceramic Surfaces

    OpenAIRE

    Hobbs, Thomas G.

    2000-01-01

    A variety of commonly available household and industrial ceramic items and some specialty glass materials were assayed by alpha pulse counting and ion chamber voltage measurements for radioactivity concentrations. Identification of radionuclides in some of the items was performed by gamma spectroscopy. The samples included tableware, construction tiles and decorative tiles, figurines, and other products with a clay based composition. The concentrations of radioactivity ranged from near backgr...

  19. Piezotransistive GaN microcantilevers based surface work function measurements

    Science.gov (United States)

    Bayram, Ferhat; Khan, Digangana; Li, Hongmei; Maksudul Hossain, Md.; Koley, Goutam

    2018-04-01

    Surface work function (SWF) measurements using a piezotransistive III–nitride cantilever has been demonstrated on multiple surfaces. The minimum detectable surface potential change of 10 mV was achieved with a signal to noise ratio of 3. This method was applied to determine the surface potential changes due to exposure of 5 ppm NO2 in graphene and In2O3 thin film, simultaneously with conductivity changes. The potentiometric measurements yielded 100 and 80 mV potential changes in SWFs of graphene and In2O3 respectively, which matches very well with experimental data published earlier indicating the efficacy of this readily miniaturizable measurement technique.

  20. Line Profile Measurements of the Lunar Exospheric Sodium

    Science.gov (United States)

    Oliversen, Ronald J.; Mierkiewicz, Edwin J.; Line, Michael R.; Roesler, Fred L.; Lupie, Olivia L.

    2012-01-01

    We report ongoing results of a program to measure the lunar sodium exospheric line profile from near the lunar limb out to two lunar radii (approx 3500 km). These observations are conducted from the National Solar Observatory McMath-Pierce telescope using a dual-etalon Fabry-Perot spectrometer with a resolving power of 180,600 (1.7 km/s) to measure line widths and velocity shifts of the Na D2 (5889 950 A) emission line in equatorial and polar regions at different lunar phases. The typical field of view (FOV) is 3 arcmin (approx 360 km) with an occasional smaller 1 arcmin FOV used right at the limb edge. The first data were obtained from full Moon to 3 days following full Moon (waning phase) in March 2009 as part of a demonstration run aimed at establishing techniques for a thorough study of temperatures and velocity variations in the lunar sodium exosphere. These data indicate velocity displacements from different locations off the lunar limb range between 150 and 600 m/s from the lunar rest velocity with a precision of +/- 20 to +/- 50 m/s depending on brightness. The measured Doppler line widths for observations within 10.5 arcmin of the east and south lunar limbs for observations between 5 deg and 40 deg lunar phase imply temperatures ranging decreasing from 3250 +/- 260K to 1175 +/- 150K. Additional data is now being collected on a quarterly basis since March 2011 and preliminary results will be reported.

  1. Near-surface fault detection by migrating back-scattered surface waves with and without velocity profiles

    KAUST Repository

    Yu, Han

    2016-04-26

    We demonstrate that diffraction stack migration can be used to discover the distribution of near-surface faults. The methodology is based on the assumption that near-surface faults generate detectable back-scattered surface waves from impinging surface waves. We first isolate the back-scattered surface waves by muting or FK filtering, and then migrate them by diffraction migration using the surface wave velocity as the migration velocity. Instead of summing events along trial quasi-hyperbolas, surface wave migration sums events along trial quasi-linear trajectories that correspond to the moveout of back-scattered surface waves. We have also proposed a natural migration method that utilizes the intrinsic traveltime property of the direct and the back-scattered waves at faults. For the synthetic data sets and the land data collected in Aqaba, where surface wave velocity has unexpected perturbations, we migrate the back-scattered surface waves with both predicted velocity profiles and natural Green\\'s function without velocity information. Because the latter approach avoids the need for an accurate velocity model in event summation, both the prestack and stacked migration images show competitive quality. Results with both synthetic data and field records validate the feasibility of this method. We believe applying this method to global or passive seismic data can open new opportunities in unveiling tectonic features.

  2. Coupled ADCPs can yield complete Reynolds stress tensor profiles in geophysical surface flows

    NARCIS (Netherlands)

    Vermeulen, B.; Hoitink, A.J.F.; Sassi, M.G.

    2011-01-01

    We introduce a new technique to measure profiles of each term in the Reynolds stress tensor using coupled acoustic Doppler current profilers (ADCPs). The technique is based on the variance method which is extended to the case with eight acoustic beams. Methods to analyze turbulence from a single

  3. Comparative analyses of measured evapotranspiration for various land surfaces

    Science.gov (United States)

    Suat Irmak

    2016-01-01

    There is a significant lack of continuously measured ET data for multiple land surfaces in the same area to be able to make comparisons of water use rates of different agroecosystems. This research presentation will provide continuous evapotranspiration and other surface energy balance variables measured above multiple land use and management practices.

  4. Specific surface as a measure of burial diagenesis of chalk

    DEFF Research Database (Denmark)

    Borre, Mai Kirstine; Lind, Ida; Mortensen, Jeanette

    1997-01-01

    the relative importance of the three processes, simple models have been established to illustrate changes in pore space, particle size and -shape and the resulting trends in the specific surface. Specific surface and porosity of the samples were measured using image analysis on electron micrographs of polished...... sections. Using these simple models, trends in the measured specific surface can be interpred throughout the majority of the geological sequence....

  5. Development of material measures for performance verifying surface topography measuring instruments

    International Nuclear Information System (INIS)

    Leach, Richard; Giusca, Claudiu; Rickens, Kai; Riemer, Oltmann; Rubert, Paul

    2014-01-01

    The development of two irregular-geometry material measures for performance verifying surface topography measuring instruments is described. The material measures are designed to be used to performance verify tactile and optical areal surface topography measuring instruments. The manufacture of the material measures using diamond turning followed by nickel electroforming is described in detail. Measurement results are then obtained using a traceable stylus instrument and a commercial coherence scanning interferometer, and the results are shown to agree to within the measurement uncertainties. The material measures are now commercially available as part of a suite of material measures aimed at the calibration and performance verification of areal surface topography measuring instruments

  6. Long-term pavement performance program manual for profile measurements and processing

    Science.gov (United States)

    2008-11-01

    This manual describes operational procedures for measuring longitudinal pavement profiles for the Long-Term Pavement Performance (LTPP) Program using the International Cybernetics Corporation (ICC) road profiler, Face Company Dipstick, and the rod an...

  7. Comparative investigation of optical techniques for topography measurement of rough plastic surfaces

    DEFF Research Database (Denmark)

    Bariani, Paolo; Hansen, Hans Nørgaard; Arlø, Uffe Rolf

    2003-01-01

    An experimental assessment of three-dimensional surface topography characterisation methods for use with rough plastic parts has been carried out. Also, calibration methods and measuring procedures including optimal measuring conditions have been developed and applied. The study is based on rough...... polypropylene parts manufactured by injection moulding. The mould was equipped with inserts with EDM machined surfaces (Sa  3.5 µm) in order to represent a typical tool surface for injection moulding. A focus detection laser scanning profiler, a confocal scanning laser microscope, a white light interferometer...... and, in addition, a scanning electron microscope, have been used in the analysis of plastic surfaces. This investigation has shown that topography assessment of rough plastic surfaces is critical to both white light interference microscope and confocal microscope while the focus detection laser...

  8. Oxygen accumulation on metal surfaces investigated by XPS, AES and LEIS, an issue for sputter depth profiling under UHV conditions

    Science.gov (United States)

    Steinberger, R.; Celedón, C. E.; Bruckner, B.; Roth, D.; Duchoslav, J.; Arndt, M.; Kürnsteiner, P.; Steck, T.; Faderl, J.; Riener, C. K.; Angeli, G.; Bauer, P.; Stifter, D.

    2017-07-01

    Depth profiling using surface sensitive analysis methods in combination with sputter ion etching is a common procedure for thorough material investigations, where clean surfaces free of any contamination are essential. Hence, surface analytic studies are mostly performed under ultra-high vacuum (UHV) conditions, but the cleanness of such UHV environments is usually overrated. Consequently, the current study highlights the in principle known impact of the residual gas on metal surfaces (Fe, Mg, Al, Cr and Zn) for various surface analytics methods, like X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and low-energy ion scattering (LEIS). The investigations with modern, state-of-the-art equipment showed different behaviors for the metal surfaces in UHV during acquisition: (i) no impact for Zn, even after long time, (ii) solely adsorption of oxygen for Fe, slight and slow changes for Cr and (iii) adsorption accompanied by oxide formation for Al and Mg. The efficiency of different counter measures was tested and the acquired knowledge was finally used for ZnMgAl coated steel to obtain accurate depth profiles, which exhibited before serious artifacts when data acquisition was performed in an inconsiderate way.

  9. Measuring depth profiles of residual stress with Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Enloe, W.S.; Sparks, R.G.; Paesler, M.A.

    1988-12-01

    Knowledge of the variation of residual stress is a very important factor in understanding the properties of machined surfaces. The nature of the residual stress can determine a part`s susceptibility to wear deformation, and cracking. Raman spectroscopy is known to be a very useful technique for measuring residual stress in many materials. These measurements are routinely made with a lateral resolution of 1{mu}m and an accuracy of 0.1 kbar. The variation of stress with depth; however, has not received much attention in the past. A novel technique has been developed that allows quantitative measurement of the variation of the residual stress with depth with an accuracy of 10nm in the z direction. Qualitative techniques for determining whether the stress is varying with depth are presented. It is also demonstrated that when the stress is changing over the volume sampled, errors can be introduced if the variation of the stress with depth is ignored. Computer aided data analysis is used to determine the depth dependence of the residual stress.

  10. Retrieving 4-dimensional atmospheric boundary layer structure from surface observations and profiles over a single station

    Energy Technology Data Exchange (ETDEWEB)

    Pu, Zhaoxia [Univ. of Utah, Salt Lake City, UT (United States)

    2015-10-06

    Most routine measurements from climate study facilities, such as the Department of Energy’s ARM SGP site, come from individual sites over a long period of time. While single-station data are very useful for many studies, it is challenging to obtain 3-dimensional spatial structures of atmospheric boundary layers that include prominent signatures of deep convection from these data. The principal objective of this project is to create realistic estimates of high-resolution (~ 1km × 1km horizontal grids) atmospheric boundary layer structure and the characteristics of precipitating convection. These characteristics include updraft and downdraft cumulus mass fluxes and cold pool properties over a region the size of a GCM grid column from analyses that assimilate surface mesonet observations of wind, temperature, and water vapor mixing ratio and available profiling data from single or multiple surface stations. The ultimate goal of the project is to enhance our understanding of the properties of mesoscale convective systems and also to improve their representation in analysis and numerical simulations. During the proposed period (09/15/2011–09/14/2014) and the no-cost extension period (09/15/2014–09/14/2015), significant accomplishments have been achieved relating to the stated goals. Efforts have been extended to various research and applications. Results have been published in professional journals and presented in related science team meetings and conferences. These are summarized in the report.

  11. Emergent relation between surface vapor conductance and relative humidity profiles yields evaporation rates from weather data.

    Science.gov (United States)

    Salvucci, Guido D; Gentine, Pierre

    2013-04-16

    The ability to predict terrestrial evapotranspiration (E) is limited by the complexity of rate-limiting pathways as water moves through the soil, vegetation (roots, xylem, stomata), canopy air space, and the atmospheric boundary layer. The impossibility of specifying the numerous parameters required to model this process in full spatial detail has necessitated spatially upscaled models that depend on effective parameters such as the surface vapor conductance (C(surf)). C(surf) accounts for the biophysical and hydrological effects on diffusion through the soil and vegetation substrate. This approach, however, requires either site-specific calibration of C(surf) to measured E, or further parameterization based on metrics such as leaf area, senescence state, stomatal conductance, soil texture, soil moisture, and water table depth. Here, we show that this key, rate-limiting, parameter can be estimated from an emergent relationship between the diurnal cycle of the relative humidity profile and E. The relation is that the vertical variance of the relative humidity profile is less than would occur for increased or decreased evaporation rates, suggesting that land-atmosphere feedback processes minimize this variance. It is found to hold over a wide range of climate conditions (arid-humid) and limiting factors (soil moisture, leaf area, energy). With this relation, estimates of E and C(surf) can be obtained globally from widely available meteorological measurements, many of which have been archived since the early 1900s. In conjunction with precipitation and stream flow, long-term E estimates provide insights and empirical constraints on projected accelerations of the hydrologic cycle.

  12. Radioactivity Measurements on Glazed Ceramic Surfaces.

    Science.gov (United States)

    Hobbs, T G

    2000-01-01

    A variety of commonly available household and industrial ceramic items and some specialty glass materials were assayed by alpha pulse counting and ion chamber voltage measurements for radioactivity concentrations. Identification of radionuclides in some of the items was performed by gamma spectroscopy. The samples included tableware, construction tiles and decorative tiles, figurines, and other products with a clay based composition. The concentrations of radioactivity ranged from near background to about four orders of magnitude higher. Almost every nuclide identification test demonstrated some radioactivity content from one or more of the naturally occurring radionuclide series of thorium or uranium. The glazes seemed to contribute most of the activity, although a sample of unglazed pottery greenware showed some activity. Samples of glazing paints and samples of deliberately doped glass from the World War II era were included in the test, as was a section of foam filled poster board. A glass disc with known (232)Th radioactivity concentration was cast for use as a calibration source. The results from the two assay methods are compared, and a projection of sensitivity from larger electret ion chamber devices is presented.

  13. A Study on 3-Dimensional Surface Measurement using Confocal Principle

    International Nuclear Information System (INIS)

    Kang, Young June; Song, Dae Ho; You, Weon Jae

    2001-01-01

    In modern industry, the accuracy and the sulfate-finish requirements for machined parts have been becoming ever more stringent. In addition, the measurement and understanding of surface topography is rapidly attracting the attention of the physicist and chemist as well as the engineer. Optical measuring method is used in vibration measurement, crack and defect detection with the advent of opto-mechatronics, and it is expected to play an important role in surface topography. In this study, the principle of confocal microscope is described, and the advanced 3-D surface measuring system that has better performance than the traditional confocal microscope is developed. Suitable fixtures arc developed and integrated with the computer system for generating 3-D surface and form data. Software for data acquisition and analysis of various parameters in surface geometrical features has been developed

  14. Comparison of slope and height profiles for flat synchrotron x-ray mirrors measured with a long trace profiler and a Fizeau interferometer

    International Nuclear Information System (INIS)

    Qian, J.; Assoufid, L.; Macrander, A.

    2007-01-01

    Long trace profilers (LTPS) have been used at many synchrotron radiation laboratories worldwide for over a decade to measure surface slope profiles of long grazing incidence x-ray mirrors. Phase measuring interferometers (PMIs) of the Fizeau type, on the other hand, are being used by most mirror manufacturers to accomplish the same task. However, large mirrors whose dimensions exceed the aperture of the Fizeau interferometer require measurements to be carried out at grazing incidence, and aspheric optics require the use of a null lens. While an LTP provides a direct measurement of ID slope profiles, PMIs measure area height profiles from which the slope can be obtained by a differentiation algorithm. Measurements of the two types of instruments have been found by us to be in good agreement, but to our knowledge there is no published work directly comparing the two instruments. This paper documents that comparison. We measured two different nominally flat mirrors with both the LTP in operation at the Advanced Photon Source (a type-II LTP) and a Fizeau-type PMI interferometer (Wyko model 6000). One mirror was 500 mm long and made of Zerodur, and the other mirror was 350 mm long and made of silicon. Slope error results with these instruments agree within nearly 100% (3.11 ± 0.15 (micro)rad for the LTP, and 3.11 ± 0.02 (micro)rad for the Fizeau PMI interferometer) for the medium quality Zerodur mirror with 3 (micro)rad rms nominal slope error. A significant difference was observed with the much higher quality silicon mirror. For the Si mirror, slope error data is 0.39 ± 0.08 (micro)rad from LTP measurements but it is 0.35 ± 0.01 (micro)rad from PMI interferometer measurements. The standard deviations show that the Fizeau PMI interferometer has much better measurement repeatability.

  15. ROUGHNESS ON WOOD SURFACES AND ROUGHNESS MEASUREMENT METHODS

    Directory of Open Access Journals (Sweden)

    İsmail Aydın

    2003-04-01

    Full Text Available Some visual characteristics of wood such as color, pattern and texture determine the quality of manufactured products. Surface properties of wood material are important both in production and marketing after production. Initial studies related to the roughness of wood surface were begun in early 1950’s. However, no general agreed standardization can not have been developed for wood surfaces. Surface roughness of wood is function of the production process, product type and the natural anatomical properties of wood. Contact and non-contact tracing methods are used to measure of wood surface roughness. Surface roughness also affects the gluability and wettability of wood surfaces. The success in finishing also depends on the surface roughness of wood.

  16. Automatic Measurement of Low Level Contamination on Concrete Surfaces

    International Nuclear Information System (INIS)

    Tachibana, M.; Itoh, H.; Shimada, T.; Yanagihara, S.

    2002-01-01

    Automatic measurement of radioactivity is necessary for considering cost effectiveness in final radiological survey of building structures in decommissioning nuclear facilities. The RAPID (radiation measuring pilot device for surface contamination) was developed to be applied to automatic measurement of low level contamination on concrete surfaces. The RAPID has a capability to measure contamination with detection limit of 0.14 Bq/cm2 for 60Co in 30 seconds of measurement time and its efficiency is evaluated to be 5 m2/h in a normal measurement option. It was confirmed that low level contamination on concrete surfaces could be surveyed by the RAPID efficiently compared with direct measurement by workers through its actual application

  17. Repetitive display system of line profiles for Doppler broadening measurement

    International Nuclear Information System (INIS)

    Mohri, A.; Narihara, K.; Haba, K.

    1982-10-01

    Line profiles of impurities in visible and ultraviolet regions are repetitively displayed on a CRT with an interval of 250 mu s or 500 mu s, using a system composed of a Czerny-Turner monochromator with 1 m F.L., a self-resonant optical scanner, a photomultiplier shielded against hard X-rays and electronic circuits. The profile resolution is 0.035 nm FWHM. This system can be used in the environment of strong hard X-rays. (author)

  18. Open questions in surface topography measurement: a roadmap

    International Nuclear Information System (INIS)

    Leach, Richard; Evans, Christopher; He, Liangyu; Davies, Angela; Duparré, Angela; Henning, Andrew; Jones, Christopher W; O’Connor, Daniel

    2015-01-01

    Control of surface topography has always been of vital importance for manufacturing and many other engineering and scientific disciplines. However, despite over one hundred years of quantitative surface topography measurement, there are still many open questions. At the top of the list of questions is ‘Are we getting the right answer?’ This begs the obvious question ‘How would we know?’ There are many other questions relating to applications, the appropriateness of a technique for a given scenario, or the relationship between a particular analysis and the function of the surface. In this first ‘open questions’ article we have gathered together some experts in surface topography measurement and asked them to address timely, unresolved questions about the subject. We hope that their responses will go some way to answer these questions, address areas where further research is required, and look at the future of the subject. The first section ‘Spatial content characterization for precision surfaces’ addresses the need to characterise the spatial content of precision surfaces. Whilst we have been manufacturing optics for centuries, there still isn’t a consensus on how to specify the surface for manufacture. The most common three methods for spatial characterisation are reviewed and compared, and the need for further work on quantifying measurement uncertainties is highlighted. The article is focussed on optical surfaces, but the ideas are more pervasive. Different communities refer to ‘figure, mid-spatial frequencies, and finish’ and ‘form, waviness, and roughness’, but the mathematics are identical. The second section ‘Light scattering methods’ is focussed on light scattering techniques; an important topic with in-line metrology becoming essential in many manufacturing scenarios. The potential of scattering methods has long been recognized; in the ‘smooth surface limit’ functionally significant relationships can be derived from first

  19. Influence of cooling rate on residual stress profile in veneering ceramic: measurement by hole-drilling.

    Science.gov (United States)

    Mainjot, Amélie K; Schajer, Gary S; Vanheusden, Alain J; Sadoun, Michaël J

    2011-09-01

    The manufacture of dental crowns and bridges generates residual stresses within the veneering ceramic and framework during the cooling process. Residual stress is an important factor that control the mechanical behavior of restorations. Knowing the stress distribution within the veneering ceramic as a function of depth can help the understanding of failures, particularly chipping, a well-known problem with Yttria-tetragonal-zirconia-polycrystal based fixed partial dentures. The objective of this study is to investigate the cooling rate dependence of the stress profile in veneering ceramic layered on metal and zirconia frameworks. The hole-drilling method, often used for engineering measurements, was adapted for use with veneering ceramic. The stress profile was measured in bilayered disc samples 20 mm in diameter, with a 0.7 mm thick metal or Yttria-tetragonal-zirconia-polycrystal framework and a 1.5mm thick veneering ceramic. Three different cooling procedures were investigated. The magnitude of the stresses in the surface of the veneering ceramic was found to increase with cooling rate, while the interior stresses decreased. At the surface, compressive stresses were observed in all samples. In the interior, compressive stresses were observed in metal samples and tensile in zirconia samples. Cooling rate influences the magnitude of residual stresses. These can significantly influence the mechanical behavior of metal-and zirconia-based bilayered systems. The framework material influenced the nature of the interior stresses, with zirconia samples showing a less favorable stress profile than metal. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  20. Measurement of Dynamic Friction Coefficient on the Irregular Free Surface

    International Nuclear Information System (INIS)

    Yeom, S. H.; Seo, K. S.; Lee, J. H.; Lee, K. H.

    2007-01-01

    A spent fuel storage cask must be estimated for a structural integrity when an earthquake occurs because it freely stands on ground surface without a restriction condition. Usually the integrity estimation for a seismic load is performed by a FEM analysis, the friction coefficient for a standing surface is an important parameter in seismic analysis when a sliding happens. When a storage cask is placed on an irregular ground surface, measuring a friction coefficient of an irregular surface is very difficult because the friction coefficient is affected by the surface condition. In this research, dynamic friction coefficients on the irregular surfaces between a concrete cylinder block and a flat concrete slab are measured with two methods by one direction actuator

  1. Measurement of near neighbor separations of surface atoms

    International Nuclear Information System (INIS)

    Cohen, P.I.

    Two techniques are being developed to measure the nearest neighbor distances of atoms at the surfaces of solids. Both measures extended fine structure in the excitation probability of core level electrons which are excited by an incident electron beam. This is an important problem because the structures of most surface systems are as yet unknown, even though the location of surface atoms is the basis for any quantitative understanding of the chemistry and physics of surfaces and interfaces. These methods would allow any laboratory to make in situ determinations of surface structure in conjunction with most other laboratory probes of surfaces. Each of these two techniques has different advantages; further, the combination of the two will increase confidence in the results by reducing systematic error in the data analysis

  2. Geometrical profile of material surface ablated with highpower, short-pulse lasers in ambient gas media

    Science.gov (United States)

    Vatsya, S. R.; Nikumb, S. K.

    2007-04-01

    Finer and cleaner features are expected in micro-machining with high power, ultrashort pulse lasers as the melt and evaporation phases are considerably reduced. However, a high-intensity optical beam propagating through a gaseous medium can cause its breakdown generating plasma, which is enhanced further by the self focusing effect of the medium. Photon-plasma scattering compensates somewhat for the self-focusing, but it also distorts the beam profile with consequent impact on the fabricated surface. Plasma also continues to supply heat beyond the pulse duration, which may cause melting and thus distort the features further. In the present article, we show that suitable parameters can be determined to reduce the distortion to the beam profile and balance self-focusing and plasma defocusing resulting in plasma filamentation. Well-shaped beam and plasma filaments, both have favourable impact on the fabricated features. The calculated surface features are compared with the experimentally machined crater profiles with good agreement.

  3. Surface deposition measurements of the TMI-2 gross decontamination experiment

    International Nuclear Information System (INIS)

    McIssac, C.V.; Hetzer, D.C.

    1982-01-01

    In order to measure the effectiveness of the gross decontamination experiment (principally a water spray technique) performed in the TMI-2 reactor building, the Technical Information and Examination Program's Radiation and Environment personnel made surface activity measurements before and after the experiment. In conjunction with surface sampling, thermoluminescent dosimeter (TLD) and gamma spectrometry measurements were also performed to distinguish between radiation fields and contamination. The surface sampler used to collect samples from external surfaces within the reactor building is a milling tool having four major components: a 1.27-cm constant-speed drill; a drill support assembly that allows setting sample penetration depth; filter cartridges for intake air purification and sample collection; and an air pump that forces air across the surface being sampled and through the sample filter cartridge

  4. Surface and interfacial tension measurement, theory, and applications

    CERN Document Server

    Hartland, Stanley

    2004-01-01

    This edited volume offers complete coverage of the latest theoretical, experimental, and computer-based data as summarized by leading international researchers. It promotes full understanding of the physical phenomena and mechanisms at work in surface and interfacial tensions and gradients, their direct impact on interface shape and movement, and their significance to numerous applications. Assessing methods for the accurate measurement of surface tension, interfacial tension, and contact angles, Surface and Interfacial Tension presents modern simulations of complex interfacial motions, such a

  5. NASA's Space Lidar Measurements of Earth and Planetary Surfaces

    Science.gov (United States)

    Abshire, James B.

    2010-01-01

    A lidar instrument on a spacecraft was first used to measure planetary surface height and topography on the Apollo 15 mission to the Moon in 1971, The lidar was based around a flashlamp-pumped ruby laser, and the Apollo 15-17 missions used them to make a few thousand measurements of lunar surface height from orbit. With the advent of diode pumped lasers in the late 1980s, the lifetime, efficiency, resolution and mass of lasers and space lidar all improved dramatically. These advances were utilized in NASA space missions to map the shape and surface topography of Mars with > 600 million measurements, demonstrate initial space measurements of the Earth's topography, and measured the detailed shape of asteroid. NASA's ICESat mission in Earth orbit just completed its polar ice measurement mission with almost 2 billion measurements of the Earth's surface and atmosphere, and demonstrated measurements to Antarctica and Greenland with a height resolution of a few em. Space missions presently in cruise phase and in operation include those to Mercury and a topographic mapping mission of the Moon. Orbital lidar also have been used in experiments to demonstrate laser ranging over planetary distances, including laser pulse transmission from Earth to Mars orbit. Based on the demonstrated value of the measurements, lidar is now the preferred measurement approach for many new scientific space missions. Some missions planned by NASA include a planetary mission to measure the shape and dynamics of Europa, and several Earth orbiting missions to continue monitoring ice sheet heights, measure vegetation heights, assess atmospheric CO2 concentrations, and to map the Earth surface topographic heights with 5 m spatial resolution. This presentation will give an overview of history, ongoing work, and plans for using space lidar for measurements of the surfaces of the Earth and planets.

  6. A computer-aided surface roughness measurement system

    International Nuclear Information System (INIS)

    Hughes, F.J.; Schankula, M.H.

    1983-11-01

    A diamond stylus profilometer with computer-based data acquisitions/analysis system is being used to characterize surfaces of reactor components and materials, and to examine the effects of surface topography on thermal contact conductance. The current system is described; measurement problems and system development are discussed in general terms and possible future improvements are outlined

  7. Measuring Forces between Oxide Surfaces Using the Atomic Force Microscope

    DEFF Research Database (Denmark)

    Pedersen, Henrik Guldberg; Høj, Jakob Weiland

    1996-01-01

    The interactions between colloidal particles play a major role in processing of ceramics, especially in casting processes. With the Atomic Force Microscope (AFM) it is possible to measure the inter-action force between a small oxide particle (a few micron) and a surface as function of surface...

  8. Drop shape visualization and contact angle measurement on curved surfaces.

    Science.gov (United States)

    Guilizzoni, Manfredo

    2011-12-01

    The shape and contact angles of drops on curved surfaces is experimentally investigated. Image processing, spline fitting and numerical integration are used to extract the drop contour in a number of cross-sections. The three-dimensional surfaces which describe the surface-air and drop-air interfaces can be visualized and a simple procedure to determine the equilibrium contact angle starting from measurements on curved surfaces is proposed. Contact angles on flat surfaces serve as a reference term and a procedure to measure them is proposed. Such procedure is not as accurate as the axisymmetric drop shape analysis algorithms, but it has the advantage of requiring only a side view of the drop-surface couple and no further information. It can therefore be used also for fluids with unknown surface tension and there is no need to measure the drop volume. Examples of application of the proposed techniques for distilled water drops on gemstones confirm that they can be useful for drop shape analysis and contact angle measurement on three-dimensional sculptured surfaces. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Device for radiometric measurement, e.g. of surface density

    International Nuclear Information System (INIS)

    Gregor, J.; Kopl, F.

    1973-01-01

    A design is described of a device for radiometric measurements, such as of material surface density, thickness of coating layers, surface moisture, and for the analysis of chemical composition. The device uses backscattered radiation indicated by two ionization chambers with gas filling; the radiation source is placed in between the chambers. (J.K.)

  10. High Resolution Cluster Pressure Profile Measurements with MUSTANG and Bolocam

    Science.gov (United States)

    Romero, Charles; Mason, Brian S.; Sayers, Jack; Young, Alexander; Dicker, Simon; Mroczkowski, Tony; Reese, Erik D.; Sarazin, Craig L.; Czakon, Nicole G.; Devlin, Mark J.; Korngut, Phillip

    2015-01-01

    Accurate high-resolution intracluster medium (ICM) pressure profiles will help further constrain cosmological parameters as well as baryonic physics in the cores of clusters of galaxies. MUSTANG, a 90 GHz bolometer array on the Green Bank Telescope (GBT) is among the highest resolution (9' FWHM) instruments at 90 GHz, and is among the best instruments to observe the ICM given its sensitivity. We present results from a sub-sample of the Cluster Lensing And Supernova with Hubble (CLASH) clusters of galaxies observed with both MUSTANG and Bolocam. Bolocam, a 150 GHz bolometer array on the CSO with 58' FWHM, and MUSTANG data probe different, and highly complementary, angular (size) scales. We jointly fit spherical electron pressure profiles to the two datasets and find that the addition of the high resolution MUSTANG data can considerably improve constraints on the pressure profiles. A major asset of our fitting algorithm is the ability to uniquely fit for contaminants such as point sources, and thus allowing us to determine the signal from the underlying ICM. We compare our best fit profiles to X-ray determined pressure profiles (provided by ACCEPT), where we find good agreement. Finally we investigate the implications of our results and describe ongoing work to extend this analysis to the full set of CLASH clusters viewable by the GBT, and to obtain even better results with the MUSTANG-1.5 camera

  11. Method And Apparatus For Two Dimensional Surface Property Analysis Based On Boundary Measurement

    Science.gov (United States)

    Richardson, John G.

    2005-11-15

    An apparatus and method for determining properties of a conductive film is disclosed. A plurality of probe locations selected around a periphery of the conductive film define a plurality of measurement lines between each probe location and all other probe locations. Electrical resistance may be measured along each of the measurement lines. A lumped parameter model may be developed based on the measured values of electrical resistance. The lumped parameter model may be used to estimate resistivity at one or more selected locations encompassed by the plurality of probe locations. The resistivity may be extrapolated to other physical properties if the conductive film includes a correlation between resistivity and the other physical properties. A profile of the conductive film may be developed by determining resistivity at a plurality of locations. The conductive film may be applied to a structure such that resistivity may be estimated and profiled for the structure's surface.

  12. Accuracy of Surface Plate Measurements - General Purpose Software for Flatness Measurement

    NARCIS (Netherlands)

    Meijer, J.; Heuvelman, C.J.

    1990-01-01

    Flatness departures of surface plates are generally obtained from straightness measurements of lines on the surface. A computer program has been developed for on-line measurement and evaluation, based on the simultaneous coupling of measurements in all grid points. Statistical methods are used to

  13. Whole genome expression profiling using DNA microarray for determining biocompatibility of polymeric surfaces

    DEFF Research Database (Denmark)

    Stangegaard, Michael; Wang, Zhenyu; Kutter, Jörg Peter

    2006-01-01

    conventional methods to determine biocompatibility such as cellular growth rate, morphology and the hydrophobicity of the surfaces. HeLa cells grown on polymethylmethacrylate (PMMA) or a SU-8 surface treated with HNO3-ceric ammonium nitrate (HNO3-CAN) and ethanolamine showed no differences in growth rate......, morphology or gene expression profiles as compared to HeLa cells grown in cell culture flasks. Cells grown on SU-8 treated with only HNO3-CAN showed almost the same growth rate (36 ¡ 1 h) and similar morphology as cells grown in cell culture flasks (32 ¡ 1 h), indicating good biocompatibility. However, more...... than 200 genes showed different expression levels in cells grown on SU-8 treated with HNO3-CAN compared to cells grown in cell culture flasks. This shows that gene expression profiling is a simple and precise method for determining differences in cells grown on different surfaces that are otherwise...

  14. Measurement of fatigue crack growth using low-profile eddy-current sensors

    International Nuclear Information System (INIS)

    Ditchburn, R.J.; Ibrahim, M.E.; Burke, S.K.

    2011-01-01

    Conformable spiral coils show promise as permanently mounted eddy-current sensors for the detection and monitoring of surface-breaking cracks in electrically conductive structures. Flexibility and a low profile (typically less than 0.5 mm) are key advantages that allow the sensors to be unobtrusively mounted on curved surfaces and beneath surface coatings. Furthermore, these sensors can be permanently mounted in areas that would otherwise be difficult or impossible to reach without significant disassembly. The sensors can be activated and interrogated using the same well-established electromagnetic measurement principles in eddy-current nondestructive inspection. A material test machine was used to grow through-thickness fatigue crack in a compact-tension specimen made from the aerospace-grade aluminium alloy AA2014. The growth of the crack was examined by measuring the small impedance changes of planar spiral-coil sensors attached to the specimen. The results indicate that permanently attached conformable spiral coils can be used to detect a deep crack once it has grown beneath the sensor, and then to monitor subsequent crack growth.

  15. Residual stress profiles in veneering ceramic on Y-TZP, alumina and ZTA frameworks: measurement by hole-drilling.

    Science.gov (United States)

    Fukushima, K A; Sadoun, M J; Cesar, P F; Mainjot, A K

    2014-02-01

    The residual stress profile developed within the veneering ceramic during the manufacturing process is an important predicting factor in chipping failures, which constitute a well-known problem with yttria-tetragonal-zirconia polycrystal (Y-TZP) based restorations. The objectives of this study are to measure and to compare the residual stress profile in the veneering ceramic layered on three different polycrystalline ceramic framework materials: Y-TZP, alumina polycrystal (AL) and zirconia toughened alumina (ZTA). The stress profile was measured with the hole-drilling method in bilayered disk samples of 19 mm diameter with a 0.7 mm thick Y-TZP, AL or ZTA framework and a 1.5mm thick layer of the corresponding veneering ceramic. The AL samples exhibited increasing compressive stresses with depth, while compressive stresses switching into interior tensile stresses were measured in Y-TZP samples. ZTA samples exhibited compressive stress at the ceramic surface, decreasing with depth up to 0.6mm from the surface, and then becoming compressive again near the framework. Y-TZP samples exhibited a less favorable stress profile than those of AL and ZTA samples. Results support the hypothesis of the occurrence of structural changes within the Y-TZP surface in contact with the veneering ceramic to explain the presence of tensile stresses. Even if the presence of Y-TZP in the alumina matrix seems to negatively affect the residual stress profiles in ZTA samples in comparison with AL samples, the registered profiles remain positive in terms of veneer fracture resistance. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  16. Cantilever measurements of surface stress, surface reconstruction, film stress and magnetoelastic stress of monolayersc

    Directory of Open Access Journals (Sweden)

    Jürgen Kirschner

    2008-07-01

    Full Text Available We review the application of cantilever-based stress measurements in surface science and magnetism. The application of thin (thickness appr. 0.1 mm single crystalline substrates as cantilevers has been used successfully to measure adsorbate-induced surface stress changes, lattice misfit induced film stress, and magneto-elastic stress of ferromagnetic monolayers. Surface stress changes as small as 0.01 N/m can be readily measured, and this translates into a sensitivity for adsorbate-coverage well below 0.01 of one layer. Stress as large as several GPa, beyond the elasticity limits of high strength materials, is measured, and it is ascribed to the lattice misfit between film and substrate. Our results point at the intimate relation between surface stress and surface reconstruction, stress-induced structural changes in epitaxially strained films, and strain-induced modifications of the magneto-elastic coupling in ferromagnetic monolayers.

  17. Cantilever measurements of surface stress, surface reconstruction, film stress and magnetoelastic stress of monolayers.

    Science.gov (United States)

    Sander, Dirk; Tian, Zhen; Kirschner, Jürgen

    2008-07-29

    We review the application of cantilever-based stress measurements in surface science and magnetism. The application of thin (thickness appr. 0.1 mm) single crystalline substrates as cantilevers has been used successfully to measure adsorbate-induced surface stress changes, lattice misfit induced film stress, and magneto-elastic stress of ferromagnetic monolayers. Surface stress changes as small as 0.01 N/m can be readily measured, and this translates into a sensitivity for adsorbate-coverage well below 0.01 of one layer. Stress as large as several GPa, beyond the elasticity limits of high strength materials, is measured, and it is ascribed to the lattice misfit between film and substrate. Our results point at the intimate relation between surface stress and surface reconstruction, stress-induced structural changes in epitaxially strained films, and strain-induced modifications of the magneto-elastic coupling in ferromagnetic monolayers.

  18. Summations over equilaterally triangulated surfaces and the critical string measure

    Science.gov (United States)

    Smit, Dirk-Jan

    1992-01-01

    We propose a new approach to the summation over dynamically triangulated Riemann surfaces which does not rely on properties of the potential in a matrix model. Instead, we formulate a purely algebraic discretization of critical string path integral. This is combined with a technique which assigns to each equilateral triangulation of a two-dimensional surface a Riemann surface defined over a certain finite extension of the field of rational numbers, i.e. an arthmetic surface. Thus we establish a new formulation in which the sum over randomly triangulated surfaces defines an invariant measure on the moduli space of arithmetic surfaces. It is shown that because of this it is far from obvious that this measure for large genera approximates the measure defined by the continuum theory, i.e. Liouville theory or critical string theory. In low genus this subtlety does not exist. In the case of critical string theory we explicity compute the volume of the moduli space of arithmetic surfaces in terms of the modular height function and show that for low genus it approximates correctly the continuum measure. We also discuss a continuum limit which bears some resemblance with a double scaling limit in matrix models.

  19. Summations over equilaterally triangulated surfaces and the critical string measure

    International Nuclear Information System (INIS)

    Smit, D.J.; Lawrence Berkeley Lab., CA

    1992-01-01

    We propose a new approach to the summation over dynamically triangulated Riemann surfaces which does not rely on properties of the potential in a matrix model. Instead, we formulate a purely algebraic discretization of critical string path integral. This is combined with a technique which assigns to each equilateral triangulation of a two-dimensional surface a Riemann surface defined over a certain finite extension of the field of rational numbers, i.e. an arithmetic surface. Thus we establish a new formulated in which the sum over randomly triangulated surfaces defines an invariant measure on the moduli space of arithmetic surfaces. It is shown that because of this it is far from obvious that this measure for large genera approximates the measure defined by the continuum theory, i.e. Liouville theory or critical string theory. In low genus this subtlety does not exist. In the case of critical string theory we explicitly compute the volume of the moduli space of arithmetic surfaces in terms of the modular height function and show that for low genus it approximates correctly the continuum measure. We also discuss a continuum limit which bears some resemblance with a double scaling limit in matrix models. (orig.)

  20. The association of anthropometric measurements and lipid profiles ...

    African Journals Online (AJOL)

    With respect to BMI classification systolic BP was significantly higher in obese males and females, and diastolic BP was only higher in obese females (p<0.05). According to BMIs for lipid profile, high-density lipoprotein-cholesterol (HDL-C), total cholesterol (TC) levels were found to be lower in normal females than other BMI ...

  1. [Correlation between sagittal photogrammetric measurements of the soft tissue profile and dental arches measurements].

    Science.gov (United States)

    Diouf, Joseph Samba; Touré, Bécaye; Ndiaye, Marième; Badiane, Alpha; Diop-Bâ, Khady; Ngom, Papa Ibrahima; Diagne, Falou

    2015-12-01

    Sagittal soft-tissue analyses made from photographic records (sagittal photogrammetric analysis of the soft tissues) allow orthodontists to quantify the sagittal dimension and situation of the facial soft tissues. These tissues maintain close anatomical relationships with the underlying dental arches. However, little importance has been given to the description and the comparison of the sagittal soft tissue morphology according to dental arches parameters. The purpose of this study was to determine the correlation between the sagittal photogrammetric soft tissue profile and the dental arches measurements. A cross-sectional study was performed in a group of students. Standardized facial-profile photographs were taken with each student in natural head position, and relaxed lip posture. Photogrammetric parameters were measured on paper sheet using a graduated ruler. Dental arches measurements were also performed directly into the mouth with an electronic caliper. The strength of the association between sagittal photogrammetric soft tissue measurements and dental arches parameters was investigated by a Pearson's correlation. Results were regarded as significant at p=0.05. The lips protrusion parameters were significantly and positively correlated with the dental arch lengths. The overjet was significantly and positively correlated with Ls/Sn-Sm. The overbite was significantly and negatively correlated with the sagittal labial parameters Ls/N-Ort, Li/N-Ort, Ls-E, Li E, Ls-S, Li S, Ls/Sn-Sm and Li/Sn-Sm. The correlations found in this study show the importance of taking into account the soft tissue in the diagnosis and orthodontic treatment of patients. © EDP Sciences, SFODF, 2015.

  2. Surface Emissivity Retrieved with Satellite Ultraspectral IR Measurements for Monitoring Global Change

    Science.gov (United States)

    Zhou, Daniel K.; Larar, Allen M.; Liu, Xu; Smith, William L.; Schluessel, Peter

    2009-01-01

    Surface and atmospheric thermodynamic parameters retrieved with advanced ultraspectral remote sensors aboard Earth observing satellites are critical to general atmospheric and Earth science research, climate monitoring, and weather prediction. Ultraspectral resolution infrared radiance obtained from nadir observations provide atmospheric, surface, and cloud information. Presented here is the global surface IR emissivity retrieved from Infrared Atmospheric Sounding Interferometer (IASI) measurements under "clear-sky" conditions. Fast radiative transfer models, applied to the cloud-free (or clouded) atmosphere, are used for atmospheric profile and surface parameter (or cloud parameter) retrieval. The inversion scheme, dealing with cloudy as well as cloud-free radiances observed with ultraspectral infrared sounders, has been developed to simultaneously retrieve atmospheric thermodynamic and surface (or cloud microphysical) parameters. Rapidly produced surface emissivity is initially evaluated through quality control checks on the retrievals of other impacted atmospheric and surface parameters. Surface emissivity and surface skin temperature from the current and future operational satellites can and will reveal critical information on the Earth s ecosystem and land surface type properties, which can be utilized as part of long-term monitoring for the Earth s environment and global climate change.

  3. Automated pavement horizontal curve measurement methods based on inertial measurement unit and 3D profiling data

    Directory of Open Access Journals (Sweden)

    Wenting Luo

    2016-04-01

    Full Text Available Pavement horizontal curve is designed to serve as a transition between straight segments, and its presence may cause a series of driving-related safety issues to motorists and drivers. As is recognized that traditional methods for curve geometry investigation are time consuming, labor intensive, and inaccurate, this study attempts to develop a method that can automatically conduct horizontal curve identification and measurement at network level. The digital highway data vehicle (DHDV was utilized for data collection, in which three Euler angles, driving speed, and acceleration of survey vehicle were measured with an inertial measurement unit (IMU. The 3D profiling data used for cross slope calibration was obtained with PaveVision3D Ultra technology at 1 mm resolution. In this study, the curve identification was based on the variation of heading angle, and the curve radius was calculated with kinematic method, geometry method, and lateral acceleration method. In order to verify the accuracy of the three methods, the analysis of variance (ANOVA test was applied by using the control variable of curve radius measured by field test. Based on the measured curve radius, a curve safety analysis model was used to predict the crash rates and safe driving speeds at horizontal curves. Finally, a case study on 4.35 km road segment demonstrated that the proposed method could efficiently conduct network level analysis.

  4. Validation of streamflow measurements made with M9 and RiverRay acoustic Doppler current profilers

    Science.gov (United States)

    Boldt, Justin A.; Oberg, Kevin A.

    2015-01-01

    The U.S. Geological Survey (USGS) Office of Surface Water (OSW) previously validated the use of Teledyne RD Instruments (TRDI) Rio Grande (in 2007), StreamPro (in 2006), and Broadband (in 1996) acoustic Doppler current profilers (ADCPs) for streamflow (discharge) measurements made by the USGS. Two new ADCPs, the SonTek M9 and the TRDI RiverRay, were first used in the USGS Water Mission Area programs in 2009. Since 2009, the OSW and USGS Water Science Centers (WSCs) have been conducting field measurements as part of their stream-gaging program using these ADCPs. The purpose of this paper is to document the results of USGS OSW analyses for validation of M9 and RiverRay ADCP streamflow measurements. The OSW required each participating WSC to make comparison measurements over the range of operating conditions in which the instruments were used until sufficient measurements were available. The performance of these ADCPs was evaluated for validation and to identify any present and potential problems. Statistical analyses of streamflow measurements indicate that measurements made with the SonTek M9 ADCP using firmware 2.00–3.00 or the TRDI RiverRay ADCP using firmware 44.12–44.15 are unbiased, and therefore, can continue to be used to make streamflow measurements in the USGS stream-gaging program. However, for the M9 ADCP, there are some important issues to be considered in making future measurements. Possible future work may include additional validation of streamflow measurements made with these instruments from other locations in the United States and measurement validation using updated firmware and software.

  5. Measuring evaporation from soil surfaces for environmental and ...

    African Journals Online (AJOL)

    ... in many aspects of environmental geotechnics and waste management. The paper describes the measurements made to assess the surface energy balance as well as its analysis, and presents the results of typical measurements. It also presents numerical values of the parameters and constants needed for the analysis.

  6. Sensitivity of surface resistance measurement of HTS thin films by ...

    Indian Academy of Sciences (India)

    field distribution in the resonators. The microwave surface resistance of the superconducting sample is then extracted from the measured Q value as a function of temperature. The sensitivity of the Rs measurement, that is, the relative change in the Q value with the change in the Rs value is determined for each resonator.

  7. Measurement of tendon reflexes by surface electromyography in normal subjects

    NARCIS (Netherlands)

    Stam, J.; van Crevel, H.

    1989-01-01

    A simple method for measuring the tendon reflexes was developed. A manually operated, electronic reflex hammer was applied that enabled measurement of the strength of tendon taps. Reflex responses were recorded by surface electromyography. Stimulus-response relations and latencies of tendon reflexes

  8. Quantification of displacement and velocity noise in vibrometer measurements on transversely moving or rotating surfaces

    Science.gov (United States)

    Dräbenstedt, Alexander

    2007-06-01

    The heterodyne interferometer (vibrometer) is a well established technique for measuring all kinds of mechanical vibrations in a broad range of applications. The non-contact measurement principle relies upon the Doppler (or phase-) shift that laser light experiences when it is reflected by the vibrating surface. The speckle nature of the reflected light imposes problems and creates additional measurement noise if the object is moving transversely through the laser spot or is rotating around an axis perpendicular to the laser direction. Another implication that can arise is cross coupling from in-plane vibrations into the out-of-plane measurement direction when small in-plane vibrations are present. A model is presented in this paper that describes the origin of these disturbances. Using this model it is possible to quantify the amplitude spectrum of the noise in displacement and velocity measurements. This enables the user to calculate the limits of resolvable vibration amplitudes when transverse motion is present. The results of the model have been confirmed well by measurements. In addition, the influence of the surface roughness and beam inclination on the out-of-plane vibration measurements at a tilted surface is investigated. The conditions for the measurability of the profile of a transversely moving surface are derived in this work. It is discussed that the R q-roughness parameter has to be less than λ/4 to obtain the slope information in the speckle-perturbed interferometer signal.

  9. A thermodynamic perturbation theory for the surface tension and ion density profile of a liquid metal

    International Nuclear Information System (INIS)

    Evans, R.; Kumaravadivel, R.

    1976-01-01

    A simple scheme for determining the ion density profile and the surface tension of a liquid metal is described. Assuming that the interaction between metallic pseudo-ions is of the form introduced by Evans, an approximate expression for the excess free energy of the system is derived using the thermodynamic perturbation theory of Weeks, Chandler and Anderson. This excess free energy is then minimized with respect to a parameter which specifies the ion density profile, and the surface tension is given directly. From a consideration of the dependence of the interionic forces on the electron density it is predicted that the ions should take up a very steep density profile at the liquid metal surface. This behaviour is contrasted with that to be expected for rare-gas fluids in which the interatomic forces are density-independent. The values of the surface tension calculated for liquid Na, K and Al from a simplified version of the theory are in reasonable agreement with experiment. (author)

  10. Analysis of the Influence of Fibre Diameter on Wirescanner Beam Profile Measurements

    CERN Document Server

    King, Quentin

    1988-01-01

    It is often important to be able to measure beam profiles in regions where the beam size is very small. Following concern that the profile measurement might be affected by having a beam size of the same order as the diameter of the wirescanner fibre, the effect was analysed numerically, and the results are presented.

  11. A comparison on radar range profiles between in-flight measurements and RCS-predictions

    NARCIS (Netherlands)

    Heiden, R. van der; Ewijk, L.J. van; Groen, F.C.A.

    1998-01-01

    The validation of Radar Cross Section (RCS) prediction techniques against real measurements is crucial to acquire confidence in predictions when measurements are nut available. In this paper we present the results of a comparison on one-dimensional signatures, i.e. radar range profiles. The profiles

  12. Spectrally resolved measurements of the terahertz beam profile generated from a two-color air plasma

    DEFF Research Database (Denmark)

    Pedersen, Pernille Klarskov; Zalkovskij, Maksim; Strikwerda, Andrew

    2014-01-01

    Using a THz camera and THz bandpass filters, we measure the frequency - resolved beam profile emitted from a two - color air plasma. We observe a frequency - independent emission angle from the plasma .......Using a THz camera and THz bandpass filters, we measure the frequency - resolved beam profile emitted from a two - color air plasma. We observe a frequency - independent emission angle from the plasma ....

  13. Estimating the breast surface using UWB microwave monostatic backscatter measurements.

    Science.gov (United States)

    Winters, David W; Shea, Jacob D; Madsen, Ernest L; Frank, Gary R; Van Veen, Barry D; Hagness, Susan C

    2008-01-01

    This paper presents an algorithm for estimating the location of the breast surface from scattered ultrawideband (UWB) microwave signals recorded across an antenna array. Knowing the location of the breast surface can improve imaging performance if incorporated as a priori information into recently proposed microwave imaging algorithms. These techniques transmit low-power microwaves into the breast using an antenna array, which in turn measures the scattered microwave signals for the purpose of detecting anomalies or changes in the dielectric properties of breast tissue. Our proposed surface identification algorithm consists of three procedures, the first of which estimates M points on the breast surface given M channels of measured microwave backscatter data. The second procedure applies interpolation and extrapolation to these M points to generate N > M points that are approximately uniformly distributed over the breast surface, while the third procedure uses these N points to generate a 3-D estimated breast surface. Numerical as well as experimental tests indicate that the maximum absolute error in the estimated surface generated by the algorithm is on the order of several millimeters. An error analysis conducted for a basic microwave radar imaging algorithm (least-squares narrowband beamforming) indicates that this level of error is acceptable. A key advantage of the algorithm is that it uses the same measured signals that are used for UWB microwave imaging, thereby minimizing patient scan time and avoiding the need for additional hardware.

  14. Mapping surface soil moisture with L-band radiometric measurements

    Science.gov (United States)

    Wang, James R.; Shiue, James C.; Schmugge, Thomas J.; Engman, Edwin T.

    1989-01-01

    A NASA C-130 airborne remote sensing aircraft was used to obtain four-beam pushbroom microwave radiometric measurements over two small Kansas tall-grass prairie region watersheds, during a dry-down period after heavy rainfall in May and June, 1987. While one of the watersheds had been burned 2 months before these measurements, the other had not been burned for over a year. Surface soil-moisture data were collected at the time of the aircraft measurements and correlated with the corresponding radiometric measurements, establishing a relationship for surface soil-moisture mapping. Radiometric sensitivity to soil moisture variation is higher in the burned than in the unburned watershed; surface soil moisture loss is also faster in the burned watershed.

  15. Roughness in Surface Force Measurements: Extension of DLVO Theory To Describe the Forces between Hafnia Surfaces.

    Science.gov (United States)

    Eom, Namsoon; Parsons, Drew F; Craig, Vincent S J

    2017-07-06

    The interaction between colloidal particles is commonly viewed through the lens of DLVO theory, whereby the interaction is described as the sum of the electrostatic and dispersion forces. For similar materials acting across a medium at pH values remote from the isoelectric point the theory typically involves an electrostatic repulsion that is overcome by dispersion forces at very small separations. However, the dominance of the dispersion forces at short separations is generally not seen in force measurements, with the exception of the interaction between mica surfaces. The discrepancy for silica surfaces has been attributed to hydration forces, but this does not explain the situation for titania surfaces where the dispersion forces are very much larger. Here, the interaction forces between very smooth hafnia surfaces have been measured using the colloid probe technique and the forces evaluated within the DLVO framework, including both hydration forces and the influence of roughness. The measured forces across a wide range of pH at different salt concentrations are well described with a single parameter for the surface roughness. These findings show that even small degrees of surface roughness significantly alter the form of the interaction force and therefore indicate that surface roughness needs to be included in the evaluation of surface forces between all surfaces that are not ideally smooth.

  16. "Simultaneous measurement of flame impingement and piston surface temperatures in an optically accessible spark ignition engine"

    Science.gov (United States)

    Ding, Carl-Philipp; Honza, Rene; Böhm, Benjamin; Dreizler, Andreas

    2017-04-01

    This paper shows the results of spatially resolved temperature measurements of the piston surface of an optically accessible direct injection spark ignition engine during flame impingement. High-speed thermographic phosphor thermometry (TPT), using Gd3Ga5O12:Cr,Ce, and planar laser-induced fluorescence of the hydroxyl radical (OH-PLIF) were used to investigate the temperature increase and the time and position of flame impingement at the piston surface. Measurements were conducted at two operating cases and showed heating rates of up to 16,000 K/s. The OH-PLIF measurements were used to localize flame impingement and calculate conditioned statistics of the temperature profiles. The TPT coating was characterized and its influence on the temperature measurements evaluated.

  17. Measuring and modeling surface sorption dynamics of organophosphate flame retardants on impervious surfaces

    Data.gov (United States)

    U.S. Environmental Protection Agency — The data presented in this data file is a product of a journal publication. The dataset contains measured and model predicted OPFRs gas-phase and surface-phase...

  18. Surface Moisture Measurement System Operation and Maintenance Manual

    International Nuclear Information System (INIS)

    Ritter, G.A.; Pearce, K.L.; Stokes, T.L.

    1995-12-01

    This operations and maintenance manual addresses deployment, equipment and field hazards, operating instructions, calibration verification, removal, maintenance, and other pertinent information necessary to safely operate and store the Surface Moisture Measurement System (SMMS) and Liquid Observation Well Moisture Measurement System (LOWMMS). These systems were developed primarily in support of Tank Waste Remediation System (TWRS) Safety Programs for moisture measurement in organic and ferrocyanide watch list tanks

  19. Practical aspects of tritium measurement in ground and surface waters

    Energy Technology Data Exchange (ETDEWEB)

    Nitzsche, O. [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Angewandte Physik; Hebert, D. [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Angewandte Physik

    1997-03-01

    Tritium measurements are a powerful tool in hydrological and hydrogeological investigations for detecting mean residence times of several water reservoirs. Due to the low tritium activities in precipitation, ground and surface waters a low level measurement is necessary. Therefore often the liquid scintillation counting after an electrolytic enrichment of water is used. In this paper some practical aspects and problems of measurement are discussed and the problem of contamination in low level laboratories is shown. (orig.)

  20. Determination of the High Frequency Inductance Profile of Surface Mounted Permanent Magnet Synchronous Motors

    DEFF Research Database (Denmark)

    Lu, Kaiyuan; Rasmussen, Peter Omand; Ritchie, Ewen

    2008-01-01

    ) synchronous motors. This paper presents an AC+DC measurement method for determination of the d-axis and q-axis high frequency inductance profiles of SMPM synchronous motors. This method uses DC currents to set a desired magnetic working point on the motor laminations, and then superimpose balanced small AC...... signals to measure the incremental a separate determination of the d, q inductance profiles as functions of the d, q currents. Experimental results on a commercial SMPM motor using the proposed method are presented in this paper....

  1. Measurement of Turbulent Skin Friction Drag Coefficients Produced by Distributed Surface Roughness of Pristine Marine Coatings

    DEFF Research Database (Denmark)

    Zafiryadis, Frederik; Meyer, Knud Erik; Gökhan Ergin, F.

    Skin friction drag coefficients are determined for marine antifouling coatings in pristine condition by use of Constant Temperature Anemometry (CTA) with uni-directionalhot-wires. Mean flow behaviour for varying surface roughness is analysed in zero pressure gradient, flat plate, turbulentboundary...... drag coefficients as well as roughness Reynolds numbers for the various marine coatings across the range of Rex by fitting of the van Driest profile. The results demonstrate sound agreement with the present ITTC method for determining skin friction coefficients for practically smooth surfaces at low...... layers for Reynolds numbers from Rex =1:91x105 to Rex = 9:54x105. The measurements were conducted at the Technical University of Denmark in a closed-loop wind tunnel redesigned for investigations as this. Ensemble averages of the boundary layer velocity profiles allowed for determination of skin friction...

  2. Plastic Deformations of Measured Object Surface in Contact with Undeformable Surface of Measuring Tool

    Directory of Open Access Journals (Sweden)

    Kowalik Marek

    2016-10-01

    Full Text Available Measuring errors caused by deformation (flattening of a measured object appear under the influence of pressure force and weight of the measured object. Plastic strain, arising at the contact of a measured object and an undeformable contact tip of a measuring device, can be calculated by applying the Hertz plastic solution and the hypothesis of plastic strain. In a small area of contact between two bodies pressing against one another with force F, there appears the so-called contact stress. It can sometime reach very high values, exceeding the yield point, even when the contact pressure is relatively small. In the present work, the authors describe a theoretical solution to the problem of plastic strain between two bodies. The derived relationships enable to calculate force F during measurements of a deformable object by means of an instrument with an undeformable, spherical measuring tip. By applying the τmax hypothesis, a solution was obtained for the force F in an inexplicit form. The theoretical solution was verified with the digital simulation and experimental measurement. With the FEM method, the limit length gage was modeled in interaction with the measured shaft of a diameter d larger than the nominal one of Δl value.

  3. Plastic Deformations of Measured Object Surface in Contact with Undeformable Surface of Measuring Tool

    Science.gov (United States)

    Kowalik, Marek; Rucki, Mirosław; Paszta, Piotr; Gołębski, Rafał

    2016-10-01

    Measuring errors caused by deformation (flattening) of a measured object appear under the influence of pressure force and weight of the measured object. Plastic strain, arising at the contact of a measured object and an undeformable contact tip of a measuring device, can be calculated by applying the Hertz plastic solution and the hypothesis of plastic strain. In a small area of contact between two bodies pressing against one another with force F, there appears the so-called contact stress. It can sometime reach very high values, exceeding the yield point, even when the contact pressure is relatively small. In the present work, the authors describe a theoretical solution to the problem of plastic strain between two bodies. The derived relationships enable to calculate force F during measurements of a deformable object by means of an instrument with an undeformable, spherical measuring tip. By applying the τmax hypothesis, a solution was obtained for the force F in an inexplicit form. The theoretical solution was verified with the digital simulation and experimental measurement. With the FEM method, the limit length gage was modeled in interaction with the measured shaft of a diameter d larger than the nominal one of Δl value.

  4. The role of surface chemistry in the cytotoxicity profile of graphene.

    Science.gov (United States)

    Majeed, Waqar; Bourdo, Shawn; Petibone, Dayton M; Saini, Viney; Vang, Kieng Bao; Nima, Zeid A; Alghazali, Karrer M; Darrigues, Emilie; Ghosh, Anindya; Watanabe, Fumiya; Casciano, Daniel; Ali, Syed F; Biris, Alexandru S

    2017-04-01

    Graphene and its derivative, because of their unique physical, electrical and chemical properties, are an important class of nanomaterials being proposed as foundational materials in nanomedicine as well as for a variety of industrial applications. A major limitation for graphene, when used in biomedical applications, is its poor solubility due to its rather hydrophobic nature. Therefore, chemical functionalities are commonly introduced to alter both its surface chemistry and biochemical activity. Here, we show that surface chemistry plays a major role in the toxicological profile of the graphene structures. To demonstrate this, we chemically increased the oxidation level of the pristine graphene and compared the corresponding toxicological effects along with those for the graphene oxide. X-ray photoelectron spectroscopy revealed that pristine graphene had the lowest amount of surface oxygen, while graphene oxide had the highest at 2.5% and 31%, respectively. Low and high oxygen functionalized graphene samples were found to have 6.6% and 24% surface oxygen, respectively. Our results showed a dose-dependent trend in the cytotoxicity profile, where pristine graphene was the most cytotoxic, with decreasing toxicity observed with increasing oxygen content. Increased surface oxygen also played a role in nanomaterial dispersion in water or cell culture medium over longer periods. It is likely that higher dispersity might result in graphene entering into cells as individual flakes ~1 nm thick rather than as more cytotoxic aggregates. In conclusion, changes in graphene's surface chemistry resulted in altered solubility and toxicity, suggesting that a generalized toxicity profile would be rather misleading. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  5. Mathematical description of tooth flank surface of globoidal worm gear with straight axial tooth profile

    Science.gov (United States)

    Połowniak, Piotr; Sobolak, Mariusz

    2017-12-01

    In this article, a mathematical description of tooth flank surface of the globoidal worm and worm wheel generated by the hourglass worm hob with straight tooth axial profile is presented. The kinematic system of globoidal worm gear is shown. The equation of globoid helix and tooth axial profile of worm is derived to determine worm tooth surface. Based on the equation of meshing the contact lines are obtained. The mathematical description of globoidal worm wheel tooth flank is performed on the basis of contact lines and generating the tooth side by the extreme cutting edge of worm hob. The presented mathematical model of tooth flank of TA worm and worm wheel can be used e.g. to analyse the contact pattern of the gear.

  6. Overview on the profile measurement of turbine blade and its development

    Science.gov (United States)

    Huang, Junhui; Wang, Zhao; Gao, Jianmin; Yu, Yanguang

    2010-10-01

    Turbine machinery has an extraordinary wide range of applications in the aviation, aerospace, automotive, energy and many other industries. The turbine blade is one of the most important parts of turbine machinery, and the characteristic parameters, pressure ratio of the engine and rotating speed of the turbine are all related to the shape and size of blades. Therefore, the profile measurement of turbine blade is an essential issue in the blade machining processing, however, it is difficult and particular to establish the profile measurement of turbine blade because of its complicated shapes and space angles of the blades, and the specific stringent environmental requirements need a more appropriate measurement method to the Turbine Blade profile measurement. This paper reviews the recent research and development on the Turbine Blade profile measurement methods, which mainly describes several common and advanced measurement methods, such as the traditional coordinate measuring machines, some optical measurement methods with the characteristics of non-contact like optical theodolite, three-dimensional photography, laser interferometry, as well as the laser triangulation method studied more recently and so on. Firstly, the measuring principles, the key technical issues and the applications in the Turbine Blade profile measurement of the methods which are mentioned above are described respectively in detail, and the characteristics of those methods are analyzed in this paper. Furthermore, the scope of application and limitations of those measurement methods are summed up. Finally, some views on the current research focus and perspective trend of the Turbine Blade profile measurement technology are presented.

  7. Interferometric method for measuring high velocities of diffuse surfaces

    International Nuclear Information System (INIS)

    Maron, Y.

    1978-01-01

    An interferometric method for measuring the displacement of diffuse surfaces moving with velocities of a few microsecond is presented. The method utilizes the interference between two light beams reflected from a constant area of the moving surface at two different angles. It enables the detection of high rate velocity variations. Light source of a fairly low temporal coherence and power around 100mW is needed. (author)

  8. Design of a High Viscosity Couette Flow Facility for Patterned Surface Drag Measurements

    Science.gov (United States)

    Johnson, Tyler; Lang, Amy

    2009-11-01

    Direct drag measurements can be difficult to obtain with low viscosity fluids such as air or water. In this facility, mineral oil is used as the working fluid to increase the shear stress across the surface of experimental models. A mounted conveyor creates a flow within a plexiglass tank. The experimental model of a flat or patterned surface is suspended above a moving belt. Within the gap between the model and moving belt a Couette flow with a linear velocity profile is created. PIV measurements are used to determine the exact velocities and the Reynolds numbers for each experiment. The model is suspended by bars that connect to the pillow block housing of each bearing. Drag is measured by a force gauge connected to linear roller bearings that slide along steel rods. The patterned surfaces, initially consisting of 2-D cavities, are embedded in a plexiglass plate so as to keep the total surface area constant for each experiment. First, the drag across a flat plate is measured and compared to theoretical values for laminar Couette flow. The drag for patterned surfaces is then measured and compared to a flat plate.

  9. An instrument for the measurement of road surface reflection properties

    DEFF Research Database (Denmark)

    Corell, Dennis Dan; Sørensen, K.

    2017-01-01

    Road surface reflection data in the form of standard r-tables serve as input for design calculations of road lighting installations on traffic roads. However, in several countries the use of the standard r-tables has not been verified by measurement in a long period of time, while the types of road...... surfaces in use have changed - for instance to road surface types with less noise from wheel passages. Because of this, a co-operation between the road administrations of the Nordic countries (abbreviated NMF) decided to construct a portable instrument to be used on selections of traffic roads within...

  10. Experimental Method for Measuring Dust Load on Surfaces in Rooms

    DEFF Research Database (Denmark)

    Lengweiler, Philip; Nielsen, Peter V.; Moser, Alfred

    , there is a need for better understanding of the mechanism of dust deposition and resuspension. With the presented experimental setup, the dust load on surfaces in a channel can be measured as a function of the environmental and surface conditions and the type of particles under controlled laboratory conditions.......A new experimental setup to investigate the physical process of dust deposition and resuspension on and from surfaces is introduced. Dust deposition can reduce the airborne dust concentration considerably. As a basis for developing methods to eliminate dust-related problems in rooms...

  11. Reporting central tendencies of chamber measured surface emission and oxidation.

    Science.gov (United States)

    Abichou, Tarek; Clark, Jeremy; Chanton, Jeffery

    2011-05-01

    Methane emissions, concentrations, and oxidation were measured on eleven MSW landfills in eleven states spanning from California to Pennsylvania during the three year study. The flux measurements were performed using a static chamber technique. Initial concentration samples were collected immediately after placement of the flux chamber. Oxidation of the emitted methane was evaluated using stable isotope techniques. When reporting overall surface emissions and percent oxidation for a landfill cover, central tendencies are typically used to report "averages" of the collected data. The objective of this study was to determine the best way to determine and report central tendencies. Results showed that 89% of the data sets of collected surface flux have lognormal distributions, 83% of the surface concentration data sets are also lognormal. Sixty seven percent (67%) of the isotope measured percent oxidation data sets are normally distributed. The distribution of data for all eleven landfills provides insight of the central tendencies of emissions, concentrations, and percent oxidation. When reporting the "average" measurement for both flux and concentration data collected at the surface of a landfill, statistical analyses provided insight supporting the use of the geometric mean. But the arithmetic mean can accurately represent the percent oxidation, as measured with the stable isotope technique. We examined correlations between surface CH(4) emissions and surface air CH(4) concentrations. Correlation of the concentration and flux values using the geometric mean proved to be a good fit (R(2)=0.86), indicating that surface scans are a good way of identifying locations of high emissions. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. Surface profiling of normally responding and nonreleasing basophils by flow cytometry

    DEFF Research Database (Denmark)

    Kistrup, Kasper; Poulsen, Lars Kærgaard; Jensen, Bettina Margrethe

    a maximum release blood mononuclear cells were purified by density centrifugation and using flow cytometry, basophils, defined as FceRIa+CD3-CD14-CD19-CD56-,were analysed for surface expression of relevant markers. All samples were compensated and analysed in logicle display. All gates......c, C3aR, C5aR CCR3, FPR1, ST2, CRTH2 on anti-IgE respondsive and nonreleasing basophils by flow cytometry, thereby generating a surface profile of the two phenotypes. Methods Fresh buffy coat blood (

  13. Inverse analysis of inner surface temperature history from outer surface temperature measurement of a pipe

    International Nuclear Information System (INIS)

    Kubo, S; Ioka, S; Onchi, S; Matsumoto, Y

    2010-01-01

    When slug flow runs through a pipe, nonuniform and time-varying thermal stresses develop and there is a possibility that thermal fatigue occurs. Therefore it is necessary to know the temperature distributions and the stress distributions in the pipe for the integrity assessment of the pipe. It is, however, difficult to measure the inner surface temperature directly. Therefore establishment of the estimation method of the temperature history on inner surface of pipe is needed. As a basic study on the estimation method of the temperature history on the inner surface of a pipe with slug flow, this paper presents an estimation method of the temperature on the inner surface of a plate from the temperature on the outer surface. The relationship between the temperature history on the outer surface and the inner surface is obtained analytically. Using the results of the mathematical analysis, the inverse analysis method of the inner surface temperature history estimation from the outer surface temperature history is proposed. It is found that the inner surface temperature history can be estimated from the outer surface temperature history by applying the inverse analysis method, even when it is expressed by the multiple frequency components.

  14. Intelligent sampling for the measurement of structured surfaces

    International Nuclear Information System (INIS)

    Wang, J; Jiang, X; Blunt, L A; Scott, P J; Leach, R K

    2012-01-01

    Uniform sampling in metrology has known drawbacks such as coherent spectral aliasing and a lack of efficiency in terms of measuring time and data storage. The requirement for intelligent sampling strategies has been outlined over recent years, particularly where the measurement of structured surfaces is concerned. Most of the present research on intelligent sampling has focused on dimensional metrology using coordinate-measuring machines with little reported on the area of surface metrology. In the research reported here, potential intelligent sampling strategies for surface topography measurement of structured surfaces are investigated by using numerical simulation and experimental verification. The methods include the jittered uniform method, low-discrepancy pattern sampling and several adaptive methods which originate from computer graphics, coordinate metrology and previous research by the authors. By combining the use of advanced reconstruction methods and feature-based characterization techniques, the measurement performance of the sampling methods is studied using case studies. The advantages, stability and feasibility of these techniques for practical measurements are discussed. (paper)

  15. Can foot anthropometric measurements predict dynamic plantar surface contact area?

    Directory of Open Access Journals (Sweden)

    Collins Natalie

    2009-10-01

    Full Text Available Abstract Background Previous studies have suggested that increased plantar surface area, associated with pes planus, is a risk factor for the development of lower extremity overuse injuries. The intent of this study was to determine if a single or combination of foot anthropometric measures could be used to predict plantar surface area. Methods Six foot measurements were collected on 155 subjects (97 females, 58 males, mean age 24.5 ± 3.5 years. The measurements as well as one ratio were entered into a stepwise regression analysis to determine the optimal set of measurements associated with total plantar contact area either including or excluding the toe region. The predicted values were used to calculate plantar surface area and were compared to the actual values obtained dynamically using a pressure sensor platform. Results A three variable model was found to describe the relationship between the foot measures/ratio and total plantar contact area (R2 = 0.77, p R2 = 0.76, p Conclusion The results of this study indicate that the clinician can use a combination of simple, reliable, and time efficient foot anthropometric measurements to explain over 75% of the plantar surface contact area, either including or excluding the toe region.

  16. Accuracy and reliability of three-dimensional surface reconstruction measurement

    International Nuclear Information System (INIS)

    Mizukami, Chikashi; Yamamoto, Etsuo; Ohmura, Masaki; Oiki, Hiroyuki; Tsuji, Jun; Muneta, Yuki; Tanabe, Makito; Hakuba, Nobuhiro; Azemoto, Syougo.

    1993-01-01

    We are using a new three-dimensional (3-D) surface reconstruction system to measure the temporal bones. This system offers the advantage of observation of the external aperture of the vestibular aqueduct and the porus acusticus internus in living subjects. However, its accuracy has not been confirmed. To investigate the accuracy of this new system, we measured the length of an in situ ceramic ossicular replacement prosthesis (CORP) of known length of 6.0 mm using 3-D surface reconstruction, conventional plain X-ray and polytomography. The CORP was scanned in the axial, sagittal and oblique directions. The mean measured length obtained with the 3-D surface reconstruction images was 5.94±0.21 on vertical scans, 5.91±0.27 on horizontal scans, and 6.01±0.25 on oblique scans. There were no significant differences among the measured lengths obtained in the three directions. Therefore, this 3-D surface reconstruction measurement system is considered to be reliable. Conversely, the mean measured length obtained by plain X-ray was 7.98±0.20, and by polytomography it was 7.94±0.23. These conventional methods have the inherent disadvantage of magnification of size which consequently requires correction. (author)

  17. Remote measurement of surface-water velocity using infrared videography and PIV: a proof-of-concept for Alaskan rivers

    Science.gov (United States)

    Kinzel, Paul J.; Legleiter, Carl; Nelson, Jonathan M.; Conaway, Jeffrey S.

    2017-01-01

    Thermal cameras with high sensitivity to medium and long wavelengths can resolve features at the surface of flowing water arising from turbulent mixing. Images acquired by these cameras can be processed with particle image velocimetry (PIV) to compute surface velocities based on the displacement of thermal features as they advect with the flow. We conducted a series of field measurements to test this methodology for remote sensing of surface velocities in rivers. We positioned an infrared video camera at multiple stations across bridges that spanned five rivers in Alaska. Simultaneous non-contact measurements of surface velocity were collected with a radar gun. In situ velocity profiles were collected with Acoustic Doppler Current Profilers (ADCP). Infrared image time series were collected at a frequency of 10Hz for a one-minute duration at a number of stations spaced across each bridge. Commercial PIV software used a cross-correlation algorithm to calculate pixel displacements between successive frames, which were then scaled to produce surface velocities. A blanking distance below the ADCP prevents a direct measurement of the surface velocity. However, we estimated surface velocity from the ADCP measurements using a program that normalizes each ADCP transect and combines those normalized transects to compute a mean measurement profile. The program can fit a power law to the profile and in so doing provides a velocity index, the ratio between the depth-averaged and surface velocity. For the rivers in this study, the velocity index ranged from 0.82 – 0.92. Average radar and extrapolated ADCP surface velocities were in good agreement with average infrared PIV calculations.

  18. The Zax Information Profile: a measure of college adjustment.

    Science.gov (United States)

    Sturm, D; Zax, M; Clarfield, S P; Pratt, D M

    1977-08-01

    Evaluated the effectiveness of the Zax Information Profile (ZIP), a personality test based on general fund of information, in discriminating between college students who sought mental health services and those who did not, Three successive classes of freshmen students at the Eastman School of Music of the University of Rochester were administered the ZIP. Help-seeking students were matched with non-help-seeking students for sex, age, and intellectual ability. The hypothesis that ZIP scores would differentiate between these two groups was supported by the data. The potential use of the ZIP as a predictor of college adjustment and as a useful entrance screening device was discussed.

  19. Modelling and measurements of bunch profiles at the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Papadopoulou, S. [Crete U.; Antoniou, F. [Liverpool U.; Argyropoulos, T. [CERN; Fitterer, M. [Fermilab; Hostettler, M. [CERN; Papaphilippou, Y. [CERN

    2017-07-20

    The bunch profiles in the LHC are often observed to be non-Gaussian, both at Flat Bottom (FB) and Flat Top (FT) energies. Especially at FT, an evolution of the tail population in time is observed. In this respect, the Monte-Carlo Software for IBS and Radiation effects (SIRE) is used to track different types of beam distributions. The impact of the distribution shape on the evolution of bunch characteristics is studied. The results are compared with observations from the LHC Run 2 data.

  20. Near-wall velocity profile measurement for nanofluids

    Directory of Open Access Journals (Sweden)

    Anoop Kanjirakat

    2016-01-01

    Full Text Available We perform near-wall velocity measurements of a SiO2–water nanofluid inside a microchannel. Nanoparticle image velocimetry measurements at three visible depths within 500 nm of the wall are conducted. We evaluate the optical properties of the nanofluid and their effect on the measurement technique. The results indicate that the small effect of the nanoparticles on the optical properties of the suspension have a negligible effect on the measurement technique. Our measurements show an increase in nanofluid velocity gradients near the walls, with no measurable slip, relative to the equivalent basefluid flow. We conjecture that particle migration induced by shear may have caused this increase. The effect of this increase in the measured near wall velocity gradient has implications on the viscosity measurement for these fluids.

  1. Surface temperature measurement of plasma facing components in tokamaks

    International Nuclear Information System (INIS)

    Amiel, Stephane

    2014-01-01

    During this PhD, the challenges on the non-intrusive surface temperature measurements of metallic plasma facing components in tokamaks are reported. Indeed, a precise material emissivity value is needed for classical infrared methods and the environment contribution has to be known particularly for low emissivities materials. Although methods have been developed to overcome these issues, they have been implemented solely for dedicated experiments. In any case, none of these methods are suitable for surface temperature measurement in tokamaks.The active pyrometry introduced in this study allows surface temperature measurements independently of reflected flux and emissivities using pulsed and modulated photothermal effect. This method has been validated in laboratory on metallic materials with reflected fluxes for pulsed and modulated modes. This experimental validation is coupled with a surface temperature variation induced by photothermal effect and temporal signal evolvement modelling in order to optimize both the heating source characteristics and the data acquisition and treatment. The experimental results have been used to determine the application range in temperature and detection wavelengths. In this context, the design of an active pyrometry system on tokamak has been completed, based on a bicolor camera for a thermography application in metallic (or low emissivity) environment.The active pyrometry method introduced in this study is a complementary technique of classical infrared methods used for thermography in tokamak environment which allows performing local and 2D surface temperature measurements independently of reflected fluxes and emissivities. (author) [fr

  2. In situ plasma sputtering and angular distribution measurements for structured molybdenum surfaces

    Science.gov (United States)

    Li, Gary Z.; Matlock, Taylor S.; Goebel, Dan M.; Dodson, Christopher A.; Matthes, Christopher S. R.; Ghoniem, Nasr M.; E Wirz, Richard

    2017-06-01

    We present in situ sputtering yield measurements of the time-dependent erosion of flat and micro-architectured molybdenum samples in a plasma environment. The measurements are performed using the plasma interactions (Pi) Facility at UCLA, which focuses a magnetized hollow cathode plasma to a material target with an exposure diameter of approximately 1.5 cm. During plasma exposure, a scanning quartz crystal microbalance (QCM) provides angular sputtering profiles that are integrated to estimate the total sputtering yield. This technique is validated to within the scatter of previous experimental data for a planar molybdenum target exposed to argon ion energies from 100 to 300 eV. The QCM is then used to obtain in situ measurements during a 17 h exposure of a micro-architectured-surface molybdenum sample to 300 eV incident argon ions. The time-dependent angular sputtering profile is shown to deviate from classical planar profiles, demonstrating the unique temporal and spatial sputtering effects of micro-architectured materials. Notably, the sputtering yield for the micro-architectured sample is initially much less than that for planar molybdenum, but then gradually asymptotes to the value for planar molybdenum after approximately 10 h as the surface features are eroded away.

  3. Validation of the "Security Needs Assessment Profile" for measuring the profiles of security needs of Chinese forensic psychiatric inpatients.

    Science.gov (United States)

    Siu, B W M; Au-Yeung, C C Y; Chan, A W L; Chan, L S Y; Yuen, K K; Leung, H W; Yan, C K; Ng, K K; Lai, A C H; Davies, S; Collins, M

    Mapping forensic psychiatric services with the security needs of patients is a salient step in service planning, audit and review. A valid and reliable instrument for measuring the security needs of Chinese forensic psychiatric inpatients was not yet available. This study aimed to develop and validate the Chinese version of the Security Needs Assessment Profile for measuring the profiles of security needs of Chinese forensic psychiatric inpatients. The Security Needs Assessment Profile by Davis was translated into Chinese. Its face validity, content validity, construct validity and internal consistency reliability were assessed by measuring the security needs of 98 Chinese forensic psychiatric inpatients. Principal factor analysis for construct validity provided a six-factor security needs model explaining 68.7% of the variance. Based on the Cronbach's alpha coefficient, the internal consistency reliability was rated as acceptable for procedural security (0.73), and fair for both physical security (0.62) and relational security (0.58). A significant sex difference (p=0.002) in total security score was found. The Chinese version of the Security Needs Assessment Profile is a valid and reliable instrument for assessing the security needs of Chinese forensic psychiatric inpatients. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Direct measurement of Cu surface self-diffusion on a checked surface

    International Nuclear Information System (INIS)

    Cousty, Jacques; Peix, Roger; Perraillon, Bernard.

    1976-01-01

    A radiotracer technique ( 64 Cu) was developed to measure surface diffusion on copper surfaces of total impurity concentration not exceeding some 10 -3 monolayers. The apparatus used consists of a slow electron diffraction device, an Auger analysis spectrometer (CMA), an ion gun and an evaporation device assembled in an ultra-vacuum chamber holding a residual pressure below 10 -10 Torr. A sample handler enables the surface studied to be positioned in front of each of these instruments. During the diffusion treatment the chemical composition of the surface is checked intermittently, and afterwards the spread of the deposit is measured outside the ultravacuum chamber. Slices several microns thick are removed and dissolved separately in dishes containing HNO 3 . The activity is then measured with a flow counter [fr

  5. Evaluation of Satellite-Based Surface Energy Budget Products with Surface Measurements Over the Great Lakes

    Science.gov (United States)

    Wang, H.; Loeb, N. G.; Lenters, J. D.; Spence, C.; Blanken, P.

    2017-12-01

    Earth's climate is fundamentally driven by the global energy balance. While Earth's energy budget at the top-of-atmosphere (TOA) is well understood, satellite-based estimates of the global mean surface energy budget yield an imbalance of 15-20 Wm-2. The data products used to infer the components of the surface energy budget are often based upon physical or empirical models and ancillary input data sets of varying quality. In order to make progress, comparisons between satellite-based estimates of the surface energy budget components and direct surface measurements are critically needed. This study evaluates surface radiative fluxes from NASA CERES EBAF and surface turbulent heat fluxes from OAFLUX by comparing them with surface station measurements from the Great Lakes Evaporation Network (GLEN). The GLEN measurements are collected using instruments on lighthouses in the Great Lakes, and include surface evaporation measurement via eddy covariance technique. The evaluation is performed for 3 offshore and 1 nearshore Great Lakes sites. We highlight results for Stannard Rock in Lake Superior, which is the farthest lighthouse from shore ( 40km from the nearest land). Relative to the GLEN observations, the OAFLUX underestimates latent heat flux by 12 Wm-2 (19 Wm-2) at Stannard Rock (4-station average), in part due to its weaker near surface wind speed, and overestimates sensible heat flux by 12 Wm-2 (6 Wm-2), which is partly contributed by its colder surface air temperature. The CERES EBAF-Surface overestimates the surface downward all-sky shortwave (longwave) flux by 8 Wm-2 (7 Wm-2) at Stannard Rock, and is comparable to the 4-station average. As a result, the surface estimated using EBAF-Surface and OAFLUX receives 16 Wm-2 (13 Wm-2) more than the GLEN observations at Stannard Rock (4-station average). The above surface energy flux differences will be further discussed based on a comparison between the input data sets used in the satellite-based estimates and

  6. Ocean Profile Measurements During the Seasonal Ice Zone Reconnaissance Surveys

    Science.gov (United States)

    2013-09-30

    appearance of the warm layer near 50 m depth dominates the upper ocean picture . We believe this is a manifestation of the Near Surface Temperature Maximum...tracking changes in the sea-ice environment of the Arctic. It will lead to greater availability of synoptic snapshots of environmental properties over

  7. Profile Measurements of BVOC Emissions from a Norway spruce

    Science.gov (United States)

    Wang, M.

    2015-12-01

    Biogenic volatile organic compounds (BVOCs) are known as a source of secondary organic aerosols (SOA) due to their high reactivity with O3 and OH in the atmosphere [1, 2]. Norway spruce is one of the dominant boreal forest species in northern Europe, which has been considered to be high monoterpene (MT) emitters [3, 4]. BVOC emissions and compound composition vary considerably under different temperature and light conditions through growing season [5, 6]. Information of vertical profile emission patterns is indispensible for understanding chemical processes and oxidation sinks within canopy and for modelling evaluation. We characterize the in-canopy BVOC emissions from a 120 years old Norway spruce in Central Sweden (Norunda, 60°05'N, 17°29'E). Air samples were taken during the growing season (June to September 2013 & 2014) from transparent dynamic branch chambers set up in a vertical profile with 4 levels (20 m, 15 m, 11 m and 3 m agl.) on the spruce. Samples were collected every hour from the chamber with Tenax-TA adsorbent tubes and a pocket pump, and analyzed later by gas chromatography and a mass selective detector (GC-MS) to quantify each trapped terpenoid compound. The emission spectrum of Norway spruce at 20 m canopy height was found to be more complex than the emissions spectra at lower canopy levels, and included isoprene, MT and SQT from June to September, while MT was the dominating terpenoid species. The emission spectra of July and August (isoprene, 14 MT and 3 SQT) were much more complex compared to June and September at the 20 m canopy level, and mainly caused by an increase of MT species during peak season. Similarly, isoprene showed a distinctive seasonal pattern, and was detected at all the heights during noon time except the bottom 3 m level during peak summer, but only at the highest layer (20 m) during noon in early or late summer. O3 vertical profile data will be available for further chemical process analysis within canopy. References[1]M

  8. Non-Contact Surface Roughness Measurement by Implementation of a Spatial Light Modulator.

    Science.gov (United States)

    Aulbach, Laura; Salazar Bloise, Félix; Lu, Min; Koch, Alexander W

    2017-03-15

    The surface structure, especially the roughness, has a significant influence on numerous parameters, such as friction and wear, and therefore estimates the quality of technical systems. In the last decades, a broad variety of surface roughness measurement methods were developed. A destructive measurement procedure or the lack of feasibility of online monitoring are the crucial drawbacks of most of these methods. This article proposes a new non-contact method for measuring the surface roughness that is straightforward to implement and easy to extend to online monitoring processes. The key element is a liquid-crystal-based spatial light modulator, integrated in an interferometric setup. By varying the imprinted phase of the modulator, a correlation between the imprinted phase and the fringe visibility of an interferogram is measured, and the surface roughness can be derived. This paper presents the theoretical approach of the method and first simulation and experimental results for a set of surface roughnesses. The experimental results are compared with values obtained by an atomic force microscope and a stylus profiler.

  9. Measuring surface flow velocity with smartphones: potential for citizen observatories

    Science.gov (United States)

    Weijs, Steven V.; Chen, Zichong; Brauchli, Tristan; Huwald, Hendrik

    2014-05-01

    Stream flow velocity is an important variable for discharge estimation and research on sediment dynamics. Given the influence of the latter on rating curves (stage-discharge relations), and the relative scarcity of direct streamflow measurements, surface velocity measurements can offer important information for, e.g., flood warning, hydropower, and hydrological science and engineering in general. With the growing amount of sensing and computing power in the hands of more outdoorsy individuals, and the advances in image processing techniques, there is now a tremendous potential to obtain hydrologically relevant data from motivated citizens. This is the main focus of the interdisciplinary "WeSenseIt" project, a citizen observatory of water. In this subproject, we investigate the feasibility of stream flow surface velocity measurements from movie clips taken by (smartphone-) cameras. First results from movie-clip derived velocity information will be shown and compared to reference measurements.

  10. Topography measurements for determining the decay factors in surface replication

    International Nuclear Information System (INIS)

    Song, J; Zheng, A; Vorburger, T V; Rubert, P

    2008-01-01

    The electro-forming technique is used at National Institute of Standards and Technology (NIST) for the production of standard reference material (SRM) 2461 standard casings to support nationwide ballistics measurement traceability and measurement quality control in the US. In order to ensure that the SRM casings are produced with virtually the same surface topography, it is necessary to test the decay factors of the replication process. Twenty-six replica casings are replicated from the same master casing for the decay factor tests. The NIST topography measurement system is used for measurements and correlations of surface topography. The topography decays are quantified by the cross-correlation function maximum CCF max . Based on the test, it is expected that 256 SRM casings can be replicated from the same master with CCF max values higher than 95%

  11. Measurement of surface crack length using image processing technology

    International Nuclear Information System (INIS)

    Nahm, Seung Hoon; Kim, Si Cheon; Kim, Yong Il; Ryu, Dae Hyun

    2001-01-01

    The development of a new experimental method is required to easily observe the growth behavior of fatigue cracks. To satisfy the requirement, an image processing technique was introduced to fatigue testing. The length of surface fatigue crack could be successfully measured by the image processing system. At first, the image data of cracks were stored into the computer while the cyclic loading was interrupted. After testing, crack length was determined using image processing software which was developed by ourselves. Block matching method was applied to the detection of surface fatigue cracks. By comparing the data measured by image processing system with the data measured by manual measurement with a microscope, the effectiveness of the image processing system was established. If the proposed method is used to monitor and observe the crack growth behavior automatically, the time and efforts for fatigue test could be dramatically reduced

  12. A lidar system for measuring atmospheric pressure and temperature profiles

    Science.gov (United States)

    Schwemmer, Geary K.; Dombrowski, Mark; Korb, C. Laurence; Milrod, Jeffry; Walden, Harvey

    1987-01-01

    The design and operation of a differential absorption lidar system capable of remotely measuring the vertical structure of tropospheric pressure and temperature are described. The measurements are based on the absorption by atmospheric oxygen of the spectrally narrowband output of two pulsed alexandrite lasers. Detailed laser output spectral characteristics, which are critical to successful lidar measurements, are presented. Spectral linewidths of 0.026 and 0.018 per cm for the lasers were measured with over 99.99 percent of the energy contained in three longitudinal modes.

  13. Two-pulse rapid remote surface contamination measurement.

    Energy Technology Data Exchange (ETDEWEB)

    Headrick, Jeffrey M.; Kulp, Thomas J.; Bisson, Scott E.; Reichardt, Thomas A.; Farrow, Roger L.

    2010-11-01

    This project demonstrated the feasibility of a 'pump-probe' optical detection method for standoff sensing of chemicals on surfaces. Such a measurement uses two optical pulses - one to remove the analyte (or a fragment of it) from the surface and the second to sense the removed material. As a particular example, this project targeted photofragmentation laser-induced fluorescence (PF-LIF) to detect of surface deposits of low-volatility chemical warfare agents (LVAs). Feasibility was demonstrated for four agent surrogates on eight realistic surfaces. Its sensitivity was established for measurements on concrete and aluminum. Extrapolations were made to demonstrate relevance to the needs of outside users. Several aspects of the surface PF-LIF physical mechanism were investigated and compared to that of vapor-phase measurements. The use of PF-LIF as a rapid screening tool to 'cue' more specific sensors was recommended. Its sensitivity was compared to that of Raman spectroscopy, which is both a potential 'confirmer' of PF-LIF 'hits' and is also a competing screening technology.

  14. Electric field vector measurements in a surface ionization wave discharge

    International Nuclear Information System (INIS)

    Goldberg, Benjamin M; Adamovich, Igor V; Lempert, Walter R; Böhm, Patrick S; Czarnetzki, Uwe

    2015-01-01

    This work presents the results of time-resolved electric field vector measurements in a short pulse duration (60 ns full width at half maximum), surface ionization wave discharge in hydrogen using a picosecond four-wave mixing technique. Electric field vector components are measured separately, using pump and Stokes beams linearly polarized in the horizontal and vertical planes, and a polarizer placed in front of the infrared detector. The time-resolved electric field vector is measured at three different locations across the discharge gap, and for three different heights above the alumina ceramic dielectric surface, ∼100, 600, and 1100 μm (total of nine different locations). The results show that after breakdown, the discharge develops as an ionization wave propagating along the dielectric surface at an average speed of 1 mm ns −1 . The surface ionization wave forms near the high voltage electrode, close to the dielectric surface (∼100 μm). The wave front is characterized by significant overshoot of both vertical and horizontal electric field vector components. Behind the wave front, the vertical field component is rapidly reduced. As the wave propagates along the dielectric surface, it also extends further away from the dielectric surface, up to ∼1 mm near the grounded electrode. The horizontal field component behind the wave front remains quite significant, to sustain the electron current toward the high voltage electrode. After the wave reaches the grounded electrode, the horizontal field component experiences a secondary rise in the quasi-dc discharge, where it sustains the current along the near-surface plasma sheet. The measurement results indicate presence of a cathode layer formed near the grounded electrode with significant cathode voltage fall, ≈3 kV, due to high current density in the discharge. The peak reduced electric field in the surface ionization wave is 85–95 Td, consistent with dc breakdown field estimated from the Paschen

  15. Inferred pressure gradient and fluid flow in a condensing sessile droplet based on the measured thickness profile

    Science.gov (United States)

    Gokhale, Shripad J.; Plawsky, Joel L.; Wayner, Peter C.; DasGupta, Sunando

    2004-06-01

    The thickness and curvature profiles of partially wetting condensing drops of 2-propanol on a quartz surface were measured using image analyzing interferometry and a new data analysis procedure. The profiles give fundamental insight into the phenomena of phase change, pressure gradient, fluid flow and spreading in a condensing drop, and the physics of interfacial phenomena in the contact line region of a polar fluid. The precursor adsorbed film and interfacial slope (a measure of the contact angle) and curvature profiles are consistent with previous concepts based on interfacial models. The curvature profiles, which were obtained using a new data reduction procedure, clearly demonstrate the convex nature of the drop near the thicker part (negative value of curvature), whereas, in the thinner region, the drop is concave (positive curvature) where the partially wetting liquid merges with a flat adsorbed film. The pressure profiles inside the drop are calculated from the augmented Young-Laplace equation showing that the pressure gradient increases with an increase in the spreading velocity (rates of condensation) to support the higher liquid flow rates associated with the growth of the drop. Internal flow is towards the point of maximum positive curvature from both the thin film and convex regions. Apolar and polar components of the spreading coefficient help describe the interfacial phenomena occurring. The experimental techniques are relatively simple but very revealing.

  16. Surface photovoltage measurements and finite element modeling of SAW devices.

    Energy Technology Data Exchange (ETDEWEB)

    Donnelly, Christine

    2012-03-01

    Over the course of a Summer 2011 internship with the MEMS department of Sandia National Laboratories, work was completed on two major projects. The first and main project of the summer involved taking surface photovoltage measurements for silicon samples, and using these measurements to determine surface recombination velocities and minority carrier diffusion lengths of the materials. The SPV method was used to fill gaps in the knowledge of material parameters that had not been determined successfully by other characterization methods. The second project involved creating a 2D finite element model of a surface acoustic wave device. A basic form of the model with the expected impedance response curve was completed, and the model is ready to be further developed for analysis of MEMS photonic resonator devices.

  17. Design parameters for measurements of local catalytic activity on surfaces

    DEFF Research Database (Denmark)

    Johansson, Martin; Johannessen, Tue; Jørgensen, Jan Hoffmann

    2006-01-01

    Computational fluid dynamics in combination with experiments is used to characterize a gas sampling device for measurements of the local catalytic activity on surfaces. The device basically consists of a quartz capillary mounted concentrically inside an aluminum tube. Reactant gas is blown toward...... the catalytic surface through the annulus between the tubes, and the gas is sampled close to the surface by the capillary. The influence of various design parameters on the lateral resolution and sensitivity of the measurements is investigated. It is found that the cuter diameter of the annulus sets the upper......, the limits of the range in reaction rate, which can be Studied are estimated. (c) 2005 Elsevier B.V. All rights reserved....

  18. Acoustics and Surface Pressure Measurements from Tandem Cylinder Configurations

    Science.gov (United States)

    Hutcheson, Florence V.; Brooks, Thomas F.; Lockard, David P.; Choudhari, Meelan M.; Stead, Daniel J.

    2014-01-01

    Acoustic and unsteady surface pressure measurements from two cylinders in tandem configurations were acquired to study the effect of spacing, surface trip and freestream velocity on the radiated noise. The Reynolds number ranged from 1.15x10(exp 5) to 2.17x10(exp 5), and the cylinder spacing varied between 1.435 and 3.7 cylinder diameters. The acoustic and surface pressure spectral characteristics associated with the different flow regimes produced by the cylinders' wake interference were identified. The dependence of the Strouhal number, peak Sound Pressure Level and spanwise coherence on cylinder spacing and flow velocity was examined. Directivity measurements were performed to determine how well the dipole assumption for the radiation of vortex shedding noise holds for the largest and smallest cylinder spacing tested.

  19. Freeform surface measurement and characterisation using a toolmakers microscope

    International Nuclear Information System (INIS)

    Wong, Francis Seung-yin; Chauh, Kong-Bieng; Venuvinod, Patri K

    2014-01-01

    Current freeform surface (FFS) characterization systems mainly cover aspects related to computer-aided design/manufacture (CAD/CAM). This paper describes a new approach that extends into computer-aided inspection (CAI).The following novel features are addressed: - ◼ Feature recognition and extraction from surface data; - ◼ Characterisation of properties of the surface's M and N vectors at individual vertex; - ◼ Development of a measuring plan using a toolmakers microscope for the inspection of the FFS; - ◼ Inspection of the actual FFS produced by CNC milling; - ◼ Verification of the measurement results and comparison with the CAD design data; Tests have shown that the deviations between the CAI and CAD data were within the estimated uncertainty limits

  20. Development of measurement standards for verifying functional performance of surface texture measuring instruments

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, A [Life and Industrial Product Development Department Olympus Corporation, 2951 Ishikawa-machi, Hachiouji-shi, Tokyo (Japan); Suzuki, H [Industrial Marketing and Planning Department Olympus Corporation, Shinjyuku Monolith, 3-1 Nishi-Shinjyuku 2-chome, Tokyo (Japan); Yanagi, K, E-mail: a_fujii@ot.olympus.co.jp [Department of Mechanical Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka-machi, Nagaoka-shi, Niigata (Japan)

    2011-08-19

    A new measurement standard is proposed for verifying overall functional performance of surface texture measuring instruments. Its surface is composed of sinusoidal surface waveforms of chirp signals along horizontal cross sections of the material measure. One of the notable features is that the amplitude of each cycle in the chirp signal form is geometrically modulated so that the maximum slope is kept constant. The maximum slope of the chirp-like signal is gradually decreased according to movement in the lateral direction. We fabricated the measurement standard by FIB processing, and it was calibrated by AFM. We tried to evaluate the functional performance of Laser Scanning Microscope by this standard in terms of amplitude response with varying slope angles. As a result, it was concluded that the proposed standard can easily evaluate the performance of surface texture measuring instruments.

  1. Silicon surface barrier detectors used for liquid hydrogen density measurement

    Science.gov (United States)

    James, D. T.; Milam, J. K.; Winslett, H. B.

    1968-01-01

    Multichannel system employing a radioisotope radiation source, strontium-90, radiation detector, and a silicon surface barrier detector, measures the local density of liquid hydrogen at various levels in a storage tank. The instrument contains electronic equipment for collecting the density information, and a data handling system for processing this information.

  2. An instrument for the measurement of road surface reflection properties

    DEFF Research Database (Denmark)

    Corell, Dennis Dan; Sørensen, K.

    2017-01-01

    Road surface reflection data in the form of standard r-tables serve as input for design calculations of road lighting installations on traffic roads. However, in several countries the use of the standard r-tables has not been verified by measurement in a long period of time, while the types of road...

  3. Surface reflectance drives nest box temperature profiles and thermal suitability for target wildlife.

    Directory of Open Access Journals (Sweden)

    Stephen R Griffiths

    Full Text Available Thermal properties of tree hollows play a major role in survival and reproduction of hollow-dependent fauna. Artificial hollows (nest boxes are increasingly being used to supplement the loss of natural hollows; however, the factors that drive nest box thermal profiles have received surprisingly little attention. We investigated how differences in surface reflectance influenced temperature profiles of nest boxes painted three different colors (dark-green, light-green, and white: total solar reflectance 5.9%, 64.4%, and 90.3% respectively using boxes designed for three groups of mammals: insectivorous bats, marsupial gliders and brushtail possums. Across the three different box designs, dark-green (low reflectance boxes experienced the highest average and maximum daytime temperatures, had the greatest magnitude of variation in daytime temperatures within the box, and were consistently substantially warmer than light-green boxes (medium reflectance, white boxes (high reflectance, and ambient air temperatures. Results from biophysical model simulations demonstrated that variation in diurnal temperature profiles generated by painting boxes either high or low reflectance colors could have significant ecophysiological consequences for animals occupying boxes, with animals in dark-green boxes at high risk of acute heat-stress and dehydration during extreme heat events. Conversely in cold weather, our modelling indicated that there are higher cumulative energy costs for mammals, particularly smaller animals, occupying light-green boxes. Given their widespread use as a conservation tool, we suggest that before boxes are installed, consideration should be given to the effect of color on nest box temperature profiles, and the resultant thermal suitability of boxes for wildlife, particularly during extremes in weather. Managers of nest box programs should consider using several different colors and installing boxes across a range of both orientations and

  4. Surface reflectance drives nest box temperature profiles and thermal suitability for target wildlife.

    Science.gov (United States)

    Griffiths, Stephen R; Rowland, Jessica A; Briscoe, Natalie J; Lentini, Pia E; Handasyde, Kathrine A; Lumsden, Linda F; Robert, Kylie A

    2017-01-01

    Thermal properties of tree hollows play a major role in survival and reproduction of hollow-dependent fauna. Artificial hollows (nest boxes) are increasingly being used to supplement the loss of natural hollows; however, the factors that drive nest box thermal profiles have received surprisingly little attention. We investigated how differences in surface reflectance influenced temperature profiles of nest boxes painted three different colors (dark-green, light-green, and white: total solar reflectance 5.9%, 64.4%, and 90.3% respectively) using boxes designed for three groups of mammals: insectivorous bats, marsupial gliders and brushtail possums. Across the three different box designs, dark-green (low reflectance) boxes experienced the highest average and maximum daytime temperatures, had the greatest magnitude of variation in daytime temperatures within the box, and were consistently substantially warmer than light-green boxes (medium reflectance), white boxes (high reflectance), and ambient air temperatures. Results from biophysical model simulations demonstrated that variation in diurnal temperature profiles generated by painting boxes either high or low reflectance colors could have significant ecophysiological consequences for animals occupying boxes, with animals in dark-green boxes at high risk of acute heat-stress and dehydration during extreme heat events. Conversely in cold weather, our modelling indicated that there are higher cumulative energy costs for mammals, particularly smaller animals, occupying light-green boxes. Given their widespread use as a conservation tool, we suggest that before boxes are installed, consideration should be given to the effect of color on nest box temperature profiles, and the resultant thermal suitability of boxes for wildlife, particularly during extremes in weather. Managers of nest box programs should consider using several different colors and installing boxes across a range of both orientations and shade profiles (i

  5. Novel dynamic flux chamber for measuring air-surface exchange of Hg(o) from soils.

    Science.gov (United States)

    Lin, Che-Jen; Zhu, Wei; Li, Xianchang; Feng, Xinbin; Sommar, Jonas; Shang, Lihai

    2012-08-21

    Quantifying the air-surface exchange of Hg(o) from soils is critical to understanding the cycling of mercury in different environmental compartments. Dynamic flux chambers (DFCs) have been widely employed for Hg(o) flux measurement over soils. However, DFCs of different sizes, shapes, and sampling flow rates yield distinct measured fluxes for a soil substrate under identical environmental conditions. In this study, we performed an integrated modeling, laboratory and field study to design a DFC capable of producing a steady and uniform air flow over a flat surface. The new DFC was fabricated using polycarbonate sheets. The internal velocity field was experimentally verified against model predictions using both theoretical and computational fluid dynamics techniques, suggesting fully developed flow with velocity profiles in excellent agreement with model results. Laboratory flux measurements demonstrated that the new design improves data reproducibility as compared to a conventional DFC, and reproduces the model-predicted flux trend with increasing sampling flow. A mathematical relationship between the sampling flow rate and surface friction velocity, a variable commonly parametrized in atmospheric models, was developed for field application. For the first time, the internal shear property of a DFC can be precisely controlled using the sampling flow rate, and the flux under atmospheric condition can be inferred from the measured flux and surface shear property. The demonstrated methodology potentially bridges the gap in measured fluxes obtained by the DFC method and the micrometeorological methods.

  6. Prediction of Facial Profile Based on Morphometric Measurements and Profile Characteristics of Permanent Maxillary Central Incisor Teeth

    Directory of Open Access Journals (Sweden)

    N Raghavendra

    2015-01-01

    Full Text Available The computation of facial profile from dental morphometrics has been a subject of great interest in forensic odontology. The use of teeth to draw a profile and facial features is valuable in times of mass disasters when body remains are unavailable due to extreme destruction. This study aims to identify and evaluate applicable parameters in the permanent maxillary central incisors and the face of an individual. A correlation of these parameters establishes a mathematical equation that further charts a tooth-facial profile table. Thirty soft and hard tissue landmarks on the face in the frontal and the lateral profiles (using standardized photographs and seven landmarks on the facial/labial surface of the clinical crown of the permanent maxillary central incisor (using casts of the maxilla were identified for the study. Based on these, a set of eight horizontal and seven vertical parameters on the face and four parameters on the tooth were created for the assessment. Internal and external correlations between the two were carried out and statistically analyzed. A logistic regression was made to predict the probability of the parameters most likely to be reproduced in the creation of the facial profile, based on tooth morphometrics. The results indicated a definite correlation between the facial and the tooth parameters. Among the multiple parameters, a definite correlation in the horizontal dimension could be established between the mouth width and the mesiodistal width (MDW of the tooth. In the vertical dimension, a definite relationship existed between the crown height of the tooth and the width of the midface (zygoma-mandible. There exist divergences in the correlation of tooth and facial parameters.

  7. A new approach of surface flux measurements using DTS

    Science.gov (United States)

    van Emmerik, T. H. M.; Wenker, K. J. R.; Rimmer, A.; de Jong, S. A. P.; Lechinsky, Y.; van de Giesen, N. C.

    2012-04-01

    Estimation of surface fluxes is a difficult task, especially over lakes. Determining latent heat flux (evaporation), sensible heat flux and ground heat flux involves measurements and (or calculations) of net radiation, air temperature, water temperature, wind speed and relative humidity. This research presents a new method to measure surface fluxes by means of Distributed Temperature Sensing (DTS). From 0.5 m above lake level to 1.5 m under lake level DTS was applied to measure temperature. Using a PVC hyperboloid construction, a floating standalone measuring device was developed. This new setup distinguished itself by the open construction, so it is almost insensitive to direct radiation. While most of the lake ground heat changes occur very close to the lake surface, most measuring methods only obtain rough results. With this construction it was possible to create a spiral shaped fiber-optic cable setup, with which a vertical spatial resolution of 0.02 m and a temporal resolution of 1 min was obtained. The new method was tested in the deep Lake Kinneret (Israel) from 6 October, 2011 to 11 October, 2011and in the shallow Lake Binaba (Ghana) from 24 October, 2011 to 28 October, 2011. This study shows that with the developed method it is possible to capture the energy fluxes within the top water layer with a high resolution. When the old low resolution method was compared with the new high resolution method, it could be concluded that the impact of the surface fluxes in the upper layer is high on the energy balance on a daily scale. During the measuring period it was possible to use the temperature measured by the DTS to determine the sensible heat flux, the latent heat flux and the ground heat flux of both lakes.

  8. Estimation of surface area and surface area measure of three-dimensional sets from digitizations

    DEFF Research Database (Denmark)

    Ziegel, Johanna; Kiderlen, Markus

    2010-01-01

    A local method for estimating surface area and surface area measure of three-dimensional objects from discrete binary images is presented. A weight is assigned to each 2 × 2 × 2 configuration of voxels and the total surface area of an object is given by summation of the local area contributions....... The method is based on an exact asymptotic result that holds for increasing resolution of the digitization. It states that the number of occurrences of a 2 ×  2 × 2 configuration is asymptotically proportional to an integral of its “h-function” with respect to the surface area measure of the object. We find...

  9. Step-height measurements on sand surfaces: A comparison between optical scanner and coordinate measuring machine

    DEFF Research Database (Denmark)

    Mohaghegh, Kamran; Yazdanbakhsh, Seyed Alireza; Tiedje, Niels Skat

    2016-01-01

    the same routine to touch the different positions on the polygonised mesh. Each measurement was repeated 5 times. The results of step height measurements on sand surfaces showed a maximum error of ± 12 µm for CMM, while scanner shows only ± 4 µm. Generally speaking, optical step height values were measured...

  10. LHC Beam Instrumentation: Beam Profile Measurements (2/3)

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    The LHC is equipped with a full suite of sophisticated beam instrumentation which has been essential for rapid commissioning, the safe increase in total stored beam power and the understanding of machine optics and accelerator physics phenomena. These lectures will introduce these systems and comment on their contributions to the various stages of beam operation. They will include details on: the beam position system and its use for real-time global orbit feedback; the beam loss system and its role in machine protection; total and bunch by bunch intensity measurements; tune measurement and feedback; diagnostics for transverse beam size measurements, abort gap monitoring and longitudinal density measurements. Issues and problems encountered along the way will also be discussed together with the prospect for future upgrades.

  11. A measurement model of multiple intelligence profiles of management graduates

    Science.gov (United States)

    Krishnan, Heamalatha; Awang, Siti Rahmah

    2017-05-01

    In this study, developing a fit measurement model and identifying the best fitting items to represent Howard Gardner's nine intelligences namely, musical intelligence, bodily-kinaesthetic intelligence, mathematical/logical intelligence, visual/spatial intelligence, verbal/linguistic intelligence, interpersonal intelligence, intrapersonal intelligence, naturalist intelligence and spiritual intelligence are the main interest in order to enhance the opportunities of the management graduates for employability. In order to develop a fit measurement model, Structural Equation Modeling (SEM) was applied. A psychometric test which is the Ability Test in Employment (ATIEm) was used as the instrument to measure the existence of nine types of intelligence of 137 University Teknikal Malaysia Melaka (UTeM) management graduates for job placement purposes. The initial measurement model contains nine unobserved variables and each unobserved variable is measured by ten observed variables. Finally, the modified measurement model deemed to improve the Normed chi-square (NC) = 1.331; Incremental Fit Index (IFI) = 0.940 and Root Mean Square of Approximation (RMSEA) = 0.049 was developed. The findings showed that the UTeM management graduates possessed all nine intelligences either high or low. Musical intelligence, mathematical/logical intelligence, naturalist intelligence and spiritual intelligence contributed highest loadings on certain items. However, most of the intelligences such as bodily kinaesthetic intelligence, visual/spatial intelligence, verbal/linguistic intelligence interpersonal intelligence and intrapersonal intelligence possessed by UTeM management graduates are just at the borderline.

  12. Measurement of sound velocity profiles in fluids for process monitoring

    International Nuclear Information System (INIS)

    Wolf, M; Kühnicke, E; Lenz, M; Bock, M

    2012-01-01

    In ultrasonic measurements, the time of flight to the object interface is often the only information that is analysed. Conventionally it is only possible to determine distances or sound velocities if the other value is known. The current paper deals with a novel method to measure the sound propagation path length and the sound velocity in media with moving scattering particles simultaneously. Since the focal position also depends on sound velocity, it can be used as a second parameter. Via calibration curves it is possible to determine the focal position and sound velocity from the measured time of flight to the focus, which is correlated to the maximum of averaged echo signal amplitude. To move focal position along the acoustic axis, an annular array is used. This allows measuring sound velocity locally resolved without any previous knowledge of the acoustic media and without a reference reflector. In previous publications the functional efficiency of this method was shown for media with constant velocities. In this work the accuracy of these measurements is improved. Furthermore first measurements and simulations are introduced for non-homogeneous media. Therefore an experimental set-up was created to generate a linear temperature gradient, which also causes a gradient of sound velocity.

  13. Passive A-band Wind Sounder (PAWS) for measuring tropospheric wind velocity profile

    Science.gov (United States)

    Miecznik, Grzegorz; Pierce, Robert; Huang, Pei; Slaymaker, Philip A.; Kaptchen, Paul; Roark, Shane; Johnson, Brian R.; Heath, Donald F.

    2007-09-01

    The Passive A-Band Wind Sounder (PAWS) was funded through NASA's Instrument Incubator Program (IIP) to determine the feasibility of measuring tropospheric wind speed profiles from Doppler shifts in absorption O II A-band. It is being pursued as a low-cost and low-risk alternative capable of providing better wind data than is currently available. The instrument concept is adapted from the Wind Imaging Interferometer (WINDII) sensor on the Upper Atmosphere Research Satellite. The operational concept for PAWS is to view an atmospheric limb over an altitude range from the surface to 20 km with a Doppler interferometer in a sun-synchronous low-earth orbit. Two orthogonal views of the same sampling volume will be used to resolve horizontal winds from measured line-of-sight winds. A breadboard instrument was developed to demonstrate the measurement approach and to optimize the design parameters for the subsequent engineering unit and future flight sensor. The breadboard instrument consists of a telescope, collimator, filter assembly, and Michelson interferometer. The instrument design is guided by a retrieval model, which helps to optimize key parameters, spectral filter and optical path difference in particular.

  14. Characterization of Rockwell hardness indenter Tip using image processing and optical profiler and evaluation of measurement uncertainty

    Directory of Open Access Journals (Sweden)

    Moona G.

    2014-01-01

    Full Text Available Hardness is a measure of the resistance of a material to be penetrated and eroded by sharp projections of other materials such as diamond. The process of creating sharp projections on any test surface is known as indentation. Hardness measurement of any material is the result of a complex process of deformation during indentation. The indenter tip geometry, which includes radius of curvature at the tip and tip angle, affects the hardness measurement by influencing the nature of the penetration process on the test surface, because every indenter deforms the specimen surface with a different geometry. The controlled indenter geometry can improve the consistency of hardness measurement. In this paper we report the estimation of two important geometrical parameters, radius of curvature and tip angle of a Rockwell indenter by using a simple method of image processing and compare the results with those obtained with a traceable 3D optical profiler. Evaluation of uncertainty in measuremts is carried out as per ISO guidelines (ISO-GUM and a detailed uncertainty budget is presented. The tip angle estimted is 119.95 degree. The radius of curvature is estimted to be 199.96 ± 0.80μm by image analysis which agrees well with the value estimated by using optical profiler i.e. 199.12 μm.

  15. Analysis of flame surface density measurements in turbulent premixed combustion

    Energy Technology Data Exchange (ETDEWEB)

    Halter, Fabien [Institut PRISME, Universite d' Orleans, 45072 Orleans (France); Chauveau, Christian; Goekalp, Iskender [Institut de Combustion, Aerothermique, Reactivite et Environnement, Centre National de la Recherche Scientifique, 45071 Orleans (France); Veynante, Denis [Laboratoire E.M2.C, Centre National de la Recherche Scientifique, Ecole Centrale Paris, 92295 Chatenay-Malabry (France)

    2009-03-15

    In premixed turbulent combustion, reaction rates can be estimated from the flame surface density. This parameter, which measures the mean flame surface area available per unit volume, may be obtained from algebraic expressions or by solving a transport equation. In this study, detailed measurements were performed on a Bunsen-type burner fed with methane/air mixtures in order to determine the local flame surface density experimentally. This burner, located in a high-pressure combustion chamber, allows investigation of turbulent premixed flames under various flow, mixture, and pressure conditions. In the present work, equivalence ratio was varied from 0.6 to 0.8 and pressure from 0.1 to 0.9 MPa. Flame front visualizations by Mie scattering laser tomography are used to obtain experimental data on the instantaneous flame front dynamics. The exact equation given by Pope is used to obtain flame surface density maps for different flame conditions. Some assumptions are made in order to access three-dimensional information from our two-dimensional experiments. Two different methodologies are proposed and tested in term of global mass balance (what enters compared to what is burned). The detailed experimental flame surface data provided for the first time in this work should progressively allow improvement of turbulent premixed flame modeling approaches. (author)

  16. NOTE: Surface dose extrapolation measurements with radiographic film

    Science.gov (United States)

    Butson, Martin J.; Cheung, Tsang; Yu, Peter K. N.; Currie, Michael

    2004-07-01

    Assessment of surface dose delivered from radiotherapy x-ray beams for optimal results should be performed both inside and outside the prescribed treatment fields. An extrapolation technique can be used with radiographic film to perform surface dose assessment for open field high energy x-ray beams. This can produce an accurate two-dimensional map of surface dose if required. Results have shown that the surface percentage dose can be estimated within ±3% of parallel plate ionization chamber results with radiographic film using a series of film layers to produce an extrapolated result. Extrapolated percentage dose assessment for 10 cm, 20 cm and 30 cm square fields was estimated to be 15% ± 2%, 29% ± 3% and 38% ± 3% at the central axis and relatively uniform across the treatment field. The corresponding parallel plate ionization chamber measurements are 16%, 27% and 37%, respectively. Surface doses are also measured outside the treatment field which are mainly due to scattered electron contamination. To achieve this result, film calibration curves must be irradiated to similar x-ray field sizes as the experimental film to minimize quantitative variations in film optical density caused by varying x-ray spectrum with field size.

  17. Key techniques for vision measurement of 3D object surface

    Science.gov (United States)

    Yang, Huachao; Zhang, Shubi; Guo, Guangli; Liu, Chao; Yu, Ruipeng

    2006-11-01

    Digital close-range photogrammetry system and machine vision are widely used in production control, quality inspection. The main aim is to provide accurate 3D objects or reconstruction of an object surface and give an expression to an object shape. First, the key techniques of camera calibration and target image positioning for 3D object surface vision measurement were briefly reviewed and analyzed in this paper. Then, an innovative and effect method for precise space coordinates measurements was proposed. Test research proved that the thought and methods we proposed about image segmentation, detection and positioning of circular marks were effective and valid. A propriety weight value for adding parameters, control points and orientation elements in bundle adjustment with self-calibration are advantageous to gaining high accuracy of space coordinates. The RMS error of check points is less than +/-1 mm, which can meet the requirement in industrial measurement with high accuracy.

  18. Combined surface acoustic wave and surface plasmon resonance measurement of collagen and fibrinogen layer physical properties

    Directory of Open Access Journals (Sweden)

    J.-M. Friedt

    2016-12-01

    Full Text Available We use an instrument combining optical (surface plasmon resonance and acoustic (Love mode surface acoustic wave device real-time measurements on a same surface for the identification of water content in collagen and fibrinogen protein layers. After calibration of the surface acoustic wave device sensitivity by copper electrodeposition and surfactant adsorption, the bound mass and its physical properties – density and optical index – are extracted from the complementary measurement techniques and lead to thickness and water ratio values compatible with the observed signal shifts. Such results are especially usefully for protein layers with a high water content as shown here for collagen on an hydrophobic surface. We obtain the following results: collagen layers include 70±20% water and are 16±3 to 19±3 nm thick for bulk concentrations ranging from 30 to 300 μg/ml. Fibrinogen layers include 50±10% water for layer thicknesses in the 6±1.5 to 13±2 nm range when the bulk concentration is in the 46 to 460 μg/ml range. Keywords: surface acoustic wave, surface plasmon resonance, collagen, fibrinogen, density, thickness

  19. Convection and surface tension profiles for aqueous droplet under microwave radiation

    Science.gov (United States)

    Kanazawa, Yushin; Asada, Masahiro; Asakuma, Yusuke; Honda, Itsuro; Phan, Chi; Parmar, Harisinh; Pareek, Vishnu; Evans, Geoffrey

    2014-08-01

    Application of microwave irradiation for chemical processes, such as emulsification and polymerization, has been reported [1,2]. Surfactant free emulsion can be produced with the help of microwave irradiation. Surface tension is an important property for the industrial process such as foaming/defoaming, wetting/dewetting and flotation. Similarly, the interfacial tension plays crucial role in separation and mixing process of two immiscible liquids, which are important unit operations of the fundamental chemical engineering. In practice, surface and interfacial tensions are often altered by introducing surfactants. In our previous research [3,4], specific property for surface tension of water droplet with salt under microwave radiation was found. For example, lower surface tension after the radiation was measured. The formation of nano-bubble will explain this behavior. Normally, the surface tension of aqueous solution increases with the salt concentration because cation and anion collect water molecule more strongly as a solvation. However, the exact mechanism of surface tension reduction by microwave radiation is not clear. We tried not only measurement of surface tension but also convection in the droplet during microwave radiation. This study investigates the influence of microwave on surface tension of aqueous solution. Moreover, relation between the concentration, temperature and droplet shape, which are related with surface tension.

  20. An experimental method for making spectral emittance and surface temperature measurements of opaque surfaces

    International Nuclear Information System (INIS)

    Moore, Travis J.; Jones, Matthew R.; Tree, Dale R.; Daniel Maynes, R.; Baxter, Larry L.

    2011-01-01

    An experimental procedure has been developed to make spectral emittance and temperature measurements. The spectral emittance of an object is calculated using measurements of the spectral emissive power and of the surface temperature of the object obtained using a Fourier transform infrared (FTIR) spectrometer. A calibration procedure is described in detail which accounts for the temperature dependence of the detector. The methods used to extract the spectral emissive power and surface temperature from measured infrared spectra were validated using a blackbody radiator at known temperatures. The average error in the measured spectral emittance was 2.1% and the average difference between the temperature inferred from the recorded spectra and the temperature indicated on the blackbody radiator was 1.2%. The method was used to measure the spectral emittance of oxidized copper at various temperatures.

  1. Recent measurements of electron density profiles of plasmas in PLADIS I, a plasma disruption simulator

    International Nuclear Information System (INIS)

    Bradley, J. III; Sharp, G.; Gahl, J.M. Kuznetsov, V.; Rockett, P.; Hunter, J.

    1995-01-01

    Tokamak disruption simulation experiments are being conducted at the University of New Mexico (UNM) using the PLADIS I plasma gun system. PLADIS I is a high power, high energy coaxial plasma gun configured to produce an intense plasma beam. First wall candidate materials are placed in the beam path to determine their response under disruption relevant energy densities. An optically thick vapor shield plasma has been observed to form above the target surface in PLADIS I. Various diagnostics have been used to determine the characteristics of the incident plasma and the vapor shielding plasma. The cross sectional area of the incident plasma beam is a critical characteristic, as it is used in the calculation of the incident plasma energy density. Recently, a HeNe interferometer in the Mach-Zehnder configuration has been constructed and used to probe the electron density of the incident plasma beam and vapor shield plasma. The object beam of the interferometer is scanned across the plasma beam on successive shots, yielding line integrals of beam density on different chords through the plasma. Data from the interferometer is used to determine the electron density profile of the incident plasma beam as a function of beam radius. This data is then used to calculate the effective beam area. Estimates. of beam area, obtained from other diagnostics such as damage targets, calorimeter arrays and off-axis measurements of surface pressure, will be compared with data from the interferometer to obtain a better estimate of the beam cross sectional area

  2. A new surface resistance measurement method with ultrahigh sensitivity

    International Nuclear Information System (INIS)

    Liang, Changnian.

    1993-01-01

    A superconducting niobium triaxial cavity has been designed and fabricated to study residual surface resistance of planar superconducting materials. The edge of a 25.4 mm or larger diameter sample in the triaxial cavity is located outside the strong field region. Therefore, the edge effects and possible losses between the thin film and the substrate have been minimized, ensuring that induced RF losses are intrinsic to the test material. The fundamental resonant frequency of the cavity is the same as the working frequency of CEBAF cavities. The cavity has a compact size compared to its TE 011 counterpart, which makes it more sensitive to the sample's loss. For even higher sensitivity, a calorimetry method has been used to measure the RF losses on the superconducting sample. At 2 K, a 2 μK temperature change can be resolved by using carbon resistor sensors. The temperature distribution caused by RF heating is measured by 16 carbon composition resistor sensors. A 0.05 μW heating power can be detected as such a resolution, which translates to a surface resistance of 0.02 nΩ at a surface magnetic field of 52 Oe. This is the most sensitive device for surface resistance measurements to date. In addition, losses due to the indium seal, coupling probes, field emission sites other than the sample, and all of the high field resonator surface, are excluded in the measurement. Surface resistance of both niobium and high-Tc superconducting thin films has been measured. A low R s of 35.2 μΩ was measured for a 25.4 mm diameter YBa 2 Cu 3 O 7 thin film at 1.5 GHz and at 2 K. The measurement result is the first result for a large area epitaxially grown thin film sample at such a low RF frequency. The abrupt disappearance of multipacting between two parallel plates has been observed and monitored with the 16 temperature mapping sensors. Field emission or some field dependent anomalous RF losses on the niobium plate have also been observed

  3. Water Surface and Velocity Measurement-River and Flume

    Directory of Open Access Journals (Sweden)

    J. H. Chandler

    2014-06-01

    Full Text Available Understanding the flow of water in natural watercourses has become increasingly important as climate change increases the incidence of extreme rainfall events which cause flooding. Vegetation in rivers and streams reduce water conveyance and natural vegetation plays a critical role in flood events which needs to be understood more fully. A funded project at Loughborough University is therefore examining the influence of vegetation upon water flow, requiring measurement of both the 3-D water surface and flow velocities. Experimental work therefore requires the measurement of water surface morphology and velocity (i.e. speed and direction in a controlled laboratory environment using a flume but also needs to be adaptable to work in a real river. Measuring the 3D topographic characteristics and velocity field of a flowing water surface is difficult and the purpose of this paper is to describe recent experimental work to achieve this. After reviewing past work in this area, the use of close range digital photogrammetry for capturing both the 3D water surface and surface velocity is described. The selected approach uses either two or three synchronised digital SLR cameras in combination with PhotoModeler for data processing, a commercial close range photogrammetric package. One critical aspect is the selection and distribution of appropriate floating marker points, which are critical if automated and appropriate measurement methods are to be used. Two distinct targeting approaches are available: either large and distinct specific floating markers or some fine material capable of providing appropriate texture. Initial work described in this paper uses specific marker points, which also provide the potential measuring surface velocity. The paper demonstrates that a high degree of measurement and marking automation is possible in a flume environment, where lighting influences can be highly controlled. When applied to a real river it is apparent that

  4. Modelling of composition and stress profiles in low temperature surface engineered stainless steel

    DEFF Research Database (Denmark)

    Jespersen, Freja Nygaard; Hattel, Jesper Henri; Somers, Marcel A. J.

    2015-01-01

    stresses are introduced in the developing case, arising from the volume expansion that accompanies the dissolution of high interstitial contents in expanded austenite. Modelling of the composition and stress profiles developing during low temperature surface engineering from the processing parameters...... temperature, time and gas composition is a prerequisite for targeted process optimization. A realistic model to simulate the developing case has to take the following influences on composition and stress into account: - a concentration dependent diffusion coefficient - trapping of nitrogen by chromium atoms...... - the effect of residual stress on diffusive flux - the effect of residual stress on solubility of interstitials - plastic accommodation of residual stress. The effect of all these contributions on composition and stress profiles will be addressed....

  5. Monitoring of temperature profiles and surface morphologies during laser sintering of alumina ceramics

    Directory of Open Access Journals (Sweden)

    Bin Qian

    2014-06-01

    Full Text Available Additive manufacturing of alumina by laser is a delicate process and small changes of processing parameters might cause less controlled and understood consequences. The real-time monitoring of temperature profiles, spectrum profiles and surface morphologies were evaluated in off-axial set-up for controlling the laser sintering of alumina ceramics. The real-time spectrometer and pyrometer were used for rapid monitoring of the thermal stability during the laser sintering process. An active illumination imaging system successfully recorded the high temperature melt pool and surrounding area simultaneously. The captured images also showed how the defects form and progress during the laser sintering process. All of these real-time monitoring methods have shown a great potential for on-line quality control during laser sintering of ceramics.

  6. Sensitivity of Landsat 8 Surface Temperature Estimates to Atmospheric Profile Data: A Study Using MODTRAN in Dryland Irrigated Systems

    KAUST Repository

    Rosas, Jorge

    2017-09-26

    The land surface temperature (LST) represents a critical element in efforts to characterize global surface energy and water fluxes, as well as being an essential climate variable in its own right. Current satellite platforms provide a range of spatial and temporal resolution radiance data from which LST can be determined. One of the most complete records of data comes via the Landsat series of satellites, which provide a continuous sequence that extends back to 1982. However, for much of this time, Landsat thermal data were provided through a single broadband thermal channel, making surface temperature retrieval challenging. To fully exploit the valuable time-series of thermal information that is available from these satellites requires efforts to better describe and understand the accuracy of temperature retrievals. Here, we contribute to these efforts by examining the impact of atmospheric correction on the estimation of LST, using atmospheric profiles derived from a range of in-situ, reanalysis, and satellite data. Radiance data from the thermal infrared (TIR) sensor onboard Landsat 8 was converted to LST by using the MODTRAN version 5.2 radiative transfer model, allowing the production of an LST time series based upon 28 Landsat overpasses. LST retrievals were then evaluated against in-situ thermal measurements collected over an arid zone farmland comprising both bare soil and vegetated surface types. Atmospheric profiles derived from AIRS, MOD07, ECMWF, NCEP, and balloon-based radiosonde data were used to drive the MODTRAN simulations. In addition to examining the direct impact of using various profile data on LST retrievals, randomly distributed errors were introduced into a range of forcing variables to better understand retrieval uncertainty. Results indicated differences in LST of up to 1 K for perturbations in emissivity and profile measurements, with the analysis also highlighting the challenges in modeling aerosol optical depth (AOD) over arid lands and

  7. Profiles

    International Nuclear Information System (INIS)

    2004-01-01

    Profiles is a synthetic overview of more than 100 national energy markets in the world, providing insightful facts and key energy statistics. A Profile is structured around 6 main items and completed by key statistics: Ministries, public agencies, energy policy are concerned; main companies in the oil, gas, electricity and coal sectors, status, shareholders; reserve, production, imports and exports, electricity and refining capacities; deregulation of prices, subsidies, taxes; consumption trends by sector, energy market shares; main energy projects, production and consumption prospects. Statistical Profiles are present in about 3 pages the main data and indicators on oil, gas, coal and electricity. (A.L.B.)

  8. Ion temperature profile measurements using the far line wings of Hα

    International Nuclear Information System (INIS)

    Bengtson, R.D.; Boedo, J.; Rowan, W.L.

    1986-01-01

    This paper presents ion temperature profiles for the outer half of the TEXT plasma using the Doppler broadened far line wings of the H α line profile. The technique depends on the assumption that the hydrogen neutrals have equilibrated with the ions through charge exchange collisions. Data reduction depends upon going far enough out on the line wing that the intensity profile is characteristic of the hottest portion of the plasma along the line of sight, thus removing the need for an inversion procedure. A Fabry-Perot interferometer is used to measure the line profiles because of its superior instrumental profile. This technique is compared with the charge exchange technique and Doppler broadening of impurities. The application to ion temperature measurements using a diagnostic neutral beam is also discussed

  9. Temperature-dependent electronic decay profiles in CZT: probe of bulk and surface properties

    Science.gov (United States)

    Kessick, Royal; Maupin, Hugh; Tepper, Gary C.; Szeles, Csaba

    2003-01-01

    The electronic performance of CZT-based gamma radiation spectrometers is governed by a synergism of bulk and surface properties. Compensation is used to increase the bulk resistivity of Cd1-xZnxTe (x~0.1), but the same electronic states that are introduced to increase the material resistivity can also trap charge and reduce the carrier lifetime. Electrical and mechanical surface defects introduced during or subsequent to crystal harvesting are also known to interfere with device performance. Using a contactless, pulsed laser microwave cavity perturbation technique, electronic decay profiles were studied in high pressure Bridgman CZT as a function of temperature. The electronic decay profile was found to depend very strongly on temperature and was modeled using a function consisting of two exponential terms with temperature-dependent amplitudes and time constants. The model was used to relate the observed temperature dependent decay kinetics in CZT to specific trap energies. It was found that, at low temperatures, the electronic decay process is dominated by a deep trap with an energy of approximately 0.69 +/- 0.1 eV from the band edge. As the temperature is increased, the charge trapping becomes dominated by a second trap with an energy of approximately 0.60 +/- 0.1 eV from the band edge. Surface damage introduces additional charge traps that significantly alter the decay kinetics particularly at low temperatures.

  10. Geometric Parameters of Cutting Tools that Can be Used for Forming Sided Surfaces with Variable Profile

    Directory of Open Access Journals (Sweden)

    Razumov M.

    2017-03-01

    Full Text Available This article describes machining technology of polyhedral surfaces with varying profile, which is provided by planetary motion of multiblade block tools. The features of the technology and urgency of the problem is indicated. The purpose of the study is to determine the minimum value of the clearance angle of the tool. Also, the study is carried out about changing the value of the front and rear corners during the formation of polygonal surface using a planetary gear. The scheme of calculating the impact of various factors on the value of the minimum clearance angle of the tool and kinematic front and rear corners of the instrument is provided. The mathematical formula for calculating the minimum clearance angle of the tool is given. Also, given the formula for determining the front and rear corners of the tool during driving. This study can be used in the calculation of the design operations forming multifaceted external surfaces with a variable profile by using the planetary gear.

  11. Developing a peak performance profile measurement for sport ...

    African Journals Online (AJOL)

    The purpose of this study was to construct a measuring instrument to assess sportspersons' psychological strengths and weaknesses. With this in mind, various developmental procedures were applied in the construction and development of an instrument over a period of more than seven years. The research was ...

  12. Metastable atom probe for measuring electron beam density profiles

    Science.gov (United States)

    Lockhart, J. M.; Zorn, J. C.

    1972-01-01

    Metastable atom probe was developed for measuring current density in electron beam as function of two arbitrary coordinates, with spatial resolution better than 0.5 mm. Probe shows effects of space charge, magnetic fields, and other factors which influence electron current density, but operates with such low beam densities that introduced perturbation is very small.

  13. ClO and O3 stratospheric profiles - Balloon microwave measurements

    Science.gov (United States)

    Waters, J. W.; Stachnik, R. A.; Hardy, J. C.; Jarnot, R. F.

    1988-01-01

    Stratospheric ClO and O3 vertical profiles were measured at 32-deg N in May 1985 and October 1986. The ClO profiles and diurnal variation are in general agreement with theory, but have somewhat less midday ClO near 34 km. Measured 35-45 km O3 is larger than theoretical, and no stratospheric O3 diurnal variation was observed, as expected. HNO3 was detected, and an H2O2 upper limit was obtained.

  14. Hydrologic Science and Satellite Measurements of Surface Water (Invited)

    Science.gov (United States)

    Alsdorf, D. E.; Mognard, N. M.; Lettenmaier, D. P.

    2010-12-01

    While significant advances continue to be made for satellite measurements of surface waters, important science and application opportunities remain. Examples include the following: (1) Our current methods of measuring floodwater dynamics are either sparsely distributed or temporally inadequate. As an example, flood depths are measured by using high water marks, which capture only the peak of the flood wave, not its temporal variability. (2) Discharge is well measured at individual points along stream networks using in-situ gauges, but these do not capture within-reach hydraulic variability such as the water surface slope changes on the rising and falling limbs of flood waves. (3) Just a 1.0 mm/day error in ET over the Congo Basin translates to a 35,000 m3/s discharge error. Knowing the discharge of the Congo River and its many tributaries should significantly improve our understanding of the water balance throughout the basin. The Congo is exemplary of many other basins around the globe. (4) Arctic hydrology is punctuated by millions of unmeasured lakes. Globally, there might be as many as 30 million lakes larger than a hectare. Storage changes in these lakes are nearly unknown, but in the Arctic such changes are likely an indication of global warming. (5) Well over 100 rivers cross international boundaries, yet the sharing of water data is poor. Overcoming this helps to better manage the entire river basin while also providing a better assessment of potential water related disasters. The Surface Water and Ocean Topography (SWOT, http://swot.jpl.nasa.gov/) mission is designed to meet these needs by providing global measurements of surface water hydrodynamics. SWOT will allow estimates of discharge in rivers wider than 100m (50m goal) and storage changes in water bodies larger than 250m by 250m (and likely as small as one hectare).

  15. Compensation method for the alignment angle error of a gear axis in profile deviation measurement

    International Nuclear Information System (INIS)

    Fang, Suping; Liu, Yongsheng; Wang, Huiyi; Taguchi, Tetsuya; Takeda, Ryuhei

    2013-01-01

    In the precision measurement of involute helical gears, the alignment angle error of a gear axis, which was caused by the assembly error of a gear measuring machine, will affect the measurement accuracy of profile deviation. A model of the involute helical gear is established under the condition that the alignment angle error of the gear axis exists. Based on the measurement theory of profile deviation, without changing the initial measurement method and data process of the gear measuring machine, a compensation method is proposed for the alignment angle error of the gear axis that is included in profile deviation measurement results. Using this method, the alignment angle error of the gear axis can be compensated for precisely. Some experiments that compare the residual alignment angle error of a gear axis after compensation for the initial alignment angle error were performed to verify the accuracy and feasibility of this method. Experimental results show that the residual alignment angle error of a gear axis included in the profile deviation measurement results is decreased by more than 85% after compensation, and this compensation method significantly improves the measurement accuracy of the profile deviation of involute helical gear. (paper)

  16. Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis.

    Science.gov (United States)

    Wilde, Markus; Ohno, Satoshi; Ogura, Shohei; Fukutani, Katsuyuki; Matsuzaki, Hiroyuki

    2016-03-29

    Nuclear reaction analysis (NRA) via the resonant (1)H((15)N,αγ)(12)C reaction is a highly effective method of depth profiling that quantitatively and non-destructively reveals the hydrogen density distribution at surfaces, at interfaces, and in the volume of solid materials with high depth resolution. The technique applies a (15)N ion beam of 6.385 MeV provided by an electrostatic accelerator and specifically detects the (1)H isotope in depths up to about 2 μm from the target surface. Surface H coverages are measured with a sensitivity in the order of ~10(13) cm(-2) (~1% of a typical atomic monolayer density) and H volume concentrations with a detection limit of ~10(18) cm(-3) (~100 at. ppm). The near-surface depth resolution is 2-5 nm for surface-normal (15)N ion incidence onto the target and can be enhanced to values below 1 nm for very flat targets by adopting a surface-grazing incidence geometry. The method is versatile and readily applied to any high vacuum compatible homogeneous material with a smooth surface (no pores). Electrically conductive targets usually tolerate the ion beam irradiation with negligible degradation. Hydrogen quantitation and correct depth analysis require knowledge of the elementary composition (besides hydrogen) and mass density of the target material. Especially in combination with ultra-high vacuum methods for in-situ target preparation and characterization, (1)H((15)N,αγ)(12)C NRA is ideally suited for hydrogen analysis at atomically controlled surfaces and nanostructured interfaces. We exemplarily demonstrate here the application of (15)N NRA at the MALT Tandem accelerator facility of the University of Tokyo to (1) quantitatively measure the surface coverage and the bulk concentration of hydrogen in the near-surface region of a H2 exposed Pd(110) single crystal, and (2) to determine the depth location and layer density of hydrogen near the interfaces of thin SiO2 films on Si(100).

  17. A subharmonic detrending or data-smoothing approach for longitudinal road profile measurements

    DEFF Research Database (Denmark)

    Gaunholt, Hans

    2001-01-01

    Commonly used figure-of-merits for longitudinal road profiles such as the International Roughness Index (IRI) and the Ride Number (RN) are based on statistical properties. Raw measured longitudinal road profile data may contain large trending components especially when the measurements are made...... without significantly corrupting the short wavelength content of the profile data. The method called sub-harmonic detrending works by fitting sub-harmonic sinusoids to the data followed by circular filtering in order to remove the trend. The method is also well suited for data-smoothing....

  18. Hadron shower profile and direction measurements in a segmented calorimeter

    International Nuclear Information System (INIS)

    Auchincloss, P.; Blair, R.; Haber, C.

    1982-01-01

    Recently a test measurement was made to see how well the direction of the shower induced by neutrino interactions could be determined in the lab-E detector at Fermilab. While the calorimeter in lab-E has very coarse sampling compared to the detectors described at this workshop, the method used to sample the shower could be employed in other more finely segmented detectors. The shower angle resolution obtained (36 mr.FWHM) is largely constrained by the sampling. In this test pulse heights in 2mm. steps across the hadron shower at five points along the shower were recorded. This was done with 20 wires and 20 fast ADC's. A standard MWPC system intended to accomplish the same task would have required about 250 wires and 250 ADC channels. This considerable saving in system complexity should be possible for any system where finely segmented pulse height measurements are required

  19. Poloidal magnetic field profile measurements on the microwave tokamak experiment using far-infrared polarimetry

    International Nuclear Information System (INIS)

    Rice, B.W.

    1992-09-01

    The measurement of plasma poloidal magnetic field (B) profiles in tokamaks with good temporal and spatial resolution has proven to be a difficult but important measurement. A large range of toroidal confinement phenomena is expected to depend sensitively on the radial variation of B including the tearing instability, sawtooth oscillations, disruptions, and transport. Experimental confirmation of theoretical models describing these phenomena has been hampered by the lack of detailed B measurements. A fifteen chord far-infrared (FIR) polarimeter has been developed to measure B in the Microwave Tokamak, Experiment (MTX). Polarimetry utilizes the well known Faraday rotation effect, which causes a rotation of the polarization of an FIR beam propagating in the poloidal plane. The rotation angle is proportional to the component of B parallel to the beam. A new technique for determining the Faraday rotation angle is introduced, based on phase measurements of a rotating polarization ellipse. This instrument has been used successfully to measure B profiles for a wide range of experiments on MTX. For ohmic discharges, measurements of the safety factor on axis give q 0 ∼ 0.75 during sawteeth and q 0 > 1 without sawteeth. Large perturbations to the polarimeter signals correlated with the sawtooth crash are observed during some discharges. Measurements in discharges with electron cyclotron heating (ECH) show a transition from a hollow to peaked J profile that is triggered by the ECH pulse. Current-ramp experiments were done to perturb the J profile from the nominal Spitzer conductivity profile. Profiles for initial current ramps and ramps starting from a stable equilibrium have been measured and are compared with a cylindrical diffusion model. Finally, the tearing mode stability equation is solved using measured J profiles. Stability predictions are in good agreement with the existence of oscillations observed on the magnetic loops

  20. Relationship between types of surface shear stress profiles and membrane fouling.

    Science.gov (United States)

    Chan, C C V; Bérubé, P R; Hall, E R

    2011-12-01

    Shear stress has been recognized as an important parameter in controlling particle back-transport from membrane surfaces. However, little is known of the relationship between transient shear conditions induced by air sparging and fouling control near membrane surfaces. In this paper, the different types of surface shear stress profiles that had beneficial effects on minimizing reversible surface fouling were examined. The relationship between different statistical shear parameters (e.g. time-averaged shear, standard deviation of shear and amplitude of shear) and fouling control that have been used by others were examined as well. It was found that the fouling rate for membranes subjected to transient shear conditions was lower than for membranes subjected to constant shear conditions. The magnitude, duration and frequency of the shear conditions were found to have an impact on the fouling rate of membranes. It was also found that although some statistical shear parameters could generally be used to relate shear and fouling, they were inadequate to relate surface shear stress to fouling, for all transient shear conditions examined. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Compact Wideband and Low-Profile Antenna Mountable on Large Metallic Surfaces

    DEFF Research Database (Denmark)

    Zhang, Shuai; Pedersen, Gert F.

    2017-01-01

    This paper proposes a compact wideband and low-profile antenna mountable on large metallic surfaces. Six rows of coupled microstrip resonators with different lengths are printed on a Teflon block. The lengths of the microstrip resonators in different rows are gradually reduced along the end...... resonance at the lowest frequency. A trapezoid-shaped capacitive-feed (C-fed) strip is utilized and also printed on the Teflon block to globally optimize the wideband impedance matching. The proposed antenna covers a relative bandwidth of 109% for VSWR

  2. 1DTempPro: analyzing temperature profiles for groundwater/surface-water exchange

    Science.gov (United States)

    Voytek, Emily B.; Drenkelfuss, Anja; Day-Lewis, Frederick D.; Healy, Richard; Lane, John W.; Werkema, Dale D.

    2014-01-01

    A new computer program, 1DTempPro, is presented for the analysis of vertical one-dimensional (1D) temperature profiles under saturated flow conditions. 1DTempPro is a graphical user interface to the U.S. Geological Survey code Variably Saturated 2-Dimensional Heat Transport (VS2DH), which numerically solves the flow and heat-transport equations. Pre- and postprocessor features allow the user to calibrate VS2DH models to estimate vertical groundwater/surface-water exchange and also hydraulic conductivity for cases where hydraulic head is known.

  3. In Vitro assessment of dentin erosion after immersion in acidic beverages: surface profile analysis and energy-dispersive X-ray fluorescence spectrometry study

    OpenAIRE

    Caneppele, Taciana Marco Ferraz; Jeronymo, Raffaela Di Iorio; Di Nicoló, Rebeca; Araújo, Maria Amélia Máximo de; Soares, Luís Eduardo Silva

    2012-01-01

    The aim of this study was to investigate the effects of some acidic drinks on dentin erosion, using methods of surface profile (SP) analysis and energy-dispersive X-ray fluorescence spectrometry (EDXRF). One hundred standardized dentin slabs obtained from bovine incisor roots were used. Dentin slabs measuring 5x5 mm were ground flat, polished and half of each specimen surface was protected with nail polish. For 60 min, the dentin surfaces were immersed in 50 mL of 5 different drinks (Gatorade...

  4. Measurement of bubbly flows in vertical channels using ultrasonic velocity profile monitor

    International Nuclear Information System (INIS)

    Aritomi, Masanori; Zhou Shirong; Takeda, Yasushi; Nakamura, Hideo; Kukita, Yutaka

    1998-01-01

    The authors have been developing measurement technique, using the Ultrasonic Doppler effect and applicable for a bubbly flow in vertical channels in order to understand their multi-dimensional flow characteristics and to offer a data base to validate numerical codes for multi-dimensional two-phase flow. Our developed measurement system is composed of an ultrasonic velocity profile monitor with a video data processing unit, which can measure simultaneously velocity profiles in both gas and liquid phases, a void fraction profile for bubbly flow in a channel, and an average bubble diameter and void fraction. In this paper, our proposed measurement system was applied to bubbly countercurrent flows in a vertical rectangular channel the followings are discussed: (1) the measurement principle, (2) the data processing process, (3) measurement accuracy and (4) further problems. (author)

  5. Prevalence and Profile of Phonological and Surface Subgroups in College Students With a History of Reading Disability.

    Science.gov (United States)

    Birch, Stacy L

    2016-07-01

    The purpose of the present study was to identify and characterize surface and phonological subgroups of readers among college students with a prior diagnosis of developmental reading disability (RD). Using a speeded naming task derived from Castles and Coltheart's subtyping study, we identified subgroups of readers from among college students with RD and then compared them on a number of component reading tasks. Most of our adults with RD showed a discrepancy in lexical versus sublexical reading skills. The majority of classified individuals were in the phonological dyslexia group, and this group's performance was worse than that of other groups on a range of reading-related tasks. Specifically, being relatively less skilled at reading nonwords compared to irregular words was associated with deficits in both sublexical and lexical tasks, and with unique deficits compared to the surface dyslexia group not only in an independent measure of phonological coding but also in spelling, rapid automatized naming, and speeded oral reading. The surface dyslexia group was small, and the pattern of results for these readers was not consistent with the predicted profile of a specific deficit in lexical and automatized reading processes. Our surface group did not show reduced skill in lexical mechanisms specifically, nor any unique deficit compared to the phonological group. These results seem more supportive of models of reading that place phonological processing impairments at the core of RD, with all other impairments being clearly subsidiary. © Hammill Institute on Disabilities 2014.

  6. Magnetic flux surface measurements at the Wendelstein 7-X stellarator

    Energy Technology Data Exchange (ETDEWEB)

    Otte, Matthias; Andreeva, Tamara; Biedermann, Christoph; Bozhenkov, Sergey; Geiger, Joachim; Sunn Pedersen, Thomas [Max-Planck-Institut fuer Plasmaphysik, Greifswald (Germany); Lazerson, Samuel [Princeton Plasma Physics Laboratory, Princeton (United States)

    2016-07-01

    Recently the first plasma operation phase of the Wendelstein 7-X stellarator has been started at IPP Greifswald. Wendelstein 7-X is an optimized stellarator with a complex superconducting magnet system consisting of 50 non-planar and 20 planar field coils and further 10 normal conducting control and 5 trim coils. The magnetic confinement and hence the expected plasma performance are decisively determined by the properties of the magnet system, especially by the existence and quality of the magnetic flux surfaces. Even small error fields may result in significant changes of the flux surface topology. Therefore, measurements of the vacuum magnetic flux surfaces have been performed before plasma operation. The first experimental results confirm the existence and quality of the flux surfaces to the full extend from low field up to the nominal field strength of B=2.5T. This includes the dedicated magnetic limiter configuration that is exclusively used for the first plasma operation. Furthermore, the measurements are indicating that the intrinsic error fields are within the tolerable range and can be controlled utilizing the trim coils as expected.

  7. Surface albedo measurements in Mexico City metropolitan area

    Energy Technology Data Exchange (ETDEWEB)

    Castro, T; Mar, B; Longoria, R; Ruiz Suarez, L. G [Centro de Ciencias de la Atmosfera, UNAM, Mexico, D.F. (Mexico); Morales, L [Instituto de Geografia, UNAM, Mexico, D.F. (Mexico)

    2001-04-01

    Optical and thermal properties of soils are important input data for the meteorological and photochemical modules of air quality models. As development of these models increase on spatial resolution good albedo data become more important. In this paper measurements of surface albedo of UV (295-385 nm) and visible (450-550 nm) radiation are reported for different urban and rural surfaces in the vicinity of Mexico City. It was found for the downtown zone and average albedo value of 0.05 which is in very good agreement with reported values for urban surfaces. Our albedo values measured in UV region for grey cement and green grass are of 0.10 and 0.009, respectively, and quite similar to those found at the literature of 0.11 and 0.008 for those type of surfaces. [Spanish] Las propiedades opticas y termicas de suelos son datos importantes para los modulos meteorologicos y fotoquimicos de los modelos de calidad del aire. Conforme aumenta la resolucion espacial del modelo se vuelve mas importante contar con buenos datos de albedo. En este articulo se presentan mediciones de albedo superficial de radiacion Ultravioleta (295-385 nm) y visible (450-550 nm) para diferentes superficies urbanas. Los valores medidos de albedo en la region UV para cemento gris y pasto verde son de 0.10 y 0.009, respectivamente, y son muy similares a los reportados en la literatura, 0.11 y 0.008 para este tipo de superficies.

  8. Influence of thermal expansion mismatch on residual stress profile in veneering ceramic layered on zirconia: Measurement by hole-drilling.

    Science.gov (United States)

    Mainjot, Amélie K; Najjar, Achref; Jakubowicz-Kohen, Boris D; Sadoun, Michaël J

    2015-09-01

    Mismatch in thermal expansion coefficient between core and veneering ceramic (Δα=αcore-αveneer, ppm/°C) is reported as a crucial parameter influencing veneer fractures with Yttria-tetragonal-zirconia-polycrystal (Y-TZP) prostheses, which still constitutes a misunderstood problem. However, the common positive Δα concept remains empirical. The objective of this study is to investigate the Δα dependence of residual stress profiles in veneering ceramic layered on Y-TZP frameworks. The stress profile was measured with the hole-drilling method in bilayered disc samples of 20mm diameter with a 0.7mm thick Y-TZP framework and a 1.5mm thick veneer layer. 3 commercial and 4 experimental veneering ceramics (n=3 per group) were used to obtain different Δα varying from -1.3ppm/°C to +3.2ppm/°C, which were determined by dilatometric analyses. Veneer fractures were observed in samples with Δα≥+2.3 or ≤-0.3ppm/°C. Residual stress profiles measured in other groups showed compressive stresses in the surface, these stresses decreasing with depth and then becoming more compressive again near the interface. Small Δα variations were shown to induce significant changes in residual stress profiles. Compressive stress near the framework was found to decrease inversely to Δα. Veneer CTE close to Y-TZP (+0.2ppm/°C Δα) gived the most favorable stress profile. Yet, near the framework, Δα-induced residual stress varied inversely to predictions. This could be explained by the hypothesis of structural changes occurrence within the Y-TZP surface. Consequently, the optimum Δα value cannot be determined before understanding Y-TZP's particular behavior when veneered. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  9. Can atom-surface potential measurements test atomic structure models?

    Science.gov (United States)

    Lonij, Vincent P A; Klauss, Catherine E; Holmgren, William F; Cronin, Alexander D

    2011-06-30

    van der Waals (vdW) atom-surface potentials can be excellent benchmarks for atomic structure calculations. This is especially true if measurements are made with two different types of atoms interacting with the same surface sample. Here we show theoretically how ratios of vdW potential strengths (e.g., C₃(K)/C₃(Na)) depend sensitively on the properties of each atom, yet these ratios are relatively insensitive to properties of the surface. We discuss how C₃ ratios depend on atomic core electrons by using a two-oscillator model to represent the contribution from atomic valence electrons and core electrons separately. We explain why certain pairs of atoms are preferable to study for future experimental tests of atomic structure calculations. A well chosen pair of atoms (e.g., K and Na) will have a C₃ ratio that is insensitive to the permittivity of the surface, whereas a poorly chosen pair (e.g., K and He) will have a ratio of C₃ values that depends more strongly on the permittivity of the surface.

  10. Comparison of neutral density profiles measured using Dα and C5+ in NSTX-U

    Science.gov (United States)

    Bell, R. E.; Scotti, F.; Diallo, A.; Leblanc, B. P.; Podesta, M.; Sabbagh, S. A.

    2017-10-01

    Edge neutral density profiles determined from two different measurements are compared on NSTX-U plasmas. Neutral density measurements were not typical on NSTX plasmas. An array of fibers dedicated to the measurement of passive emission of C5+, used to subtract background emission for charge exchange recombination spectroscopy (CHERS), can be used to infer deuterium neutral density near the plasma edge. The line emission from C5+ is dominated by charge exchange with neutral deuterium near the plasma edge. An edge neutral density diagnostic consisting of a camera with a Dα filter was installed on NSTX-U. The line-integrated measurements from both diagnostics are inverted to obtain local emissivity profiles. Neutral density is then inferred using atomics rates from ADAS and profile measurements from Thomson scattering and CHERS. Comparing neutral density profiles from the two diagnostic measurements helps determine the utility of using the more routinely available C5+ measurements for neutral density profiles. Initial comparisons show good agreement between the two measurements inside the separatrix. Supported by US DoE Contracts DE-AC02-09CH11466 and DE-AC52-07NA27344.

  11. Measurement of electron beams profile of pierce type electron source using sensor of used Tv tube

    International Nuclear Information System (INIS)

    Darsono; Suhartono; Suprapto; Elin Nuraini

    2015-01-01

    The measurement of an electron beam profile has been performed using electron beam monitor based on method of phosphorescent materials. The main components of the electron beam monitor consists of a fluorescent sensor using a used Tv tube, CCTV camera to record images on a Tv screen, video adapter as interface between CCTV and laptop, and the laptop as a viewer and data processing. Two Pierce-type electron sources diode and triode was measured the shape of electron beam profile in real time. Results of the experiments showed that the triode electron source of Pierce type gave the shape of electron beam profiles better than that of the diode electron source .The anode voltage is not so influential on the beam profile shape. The focused voltage in the triode electron source is so influence to the shape of the electron beam profile, but above 5 kV no great effect. It can be concluded that the electron beam monitor can provide real time observations and drawings shape of the electron beam profile displayed on the used Tv tube glass screen which is the real picture of the shape of the electron beam profile. Triode electron source produces a better electron beam profile than that of the diode electron source. (author)

  12. SIMS-AMS depth profiles for NASA Genesis samples: Preliminary measurements

    Energy Technology Data Exchange (ETDEWEB)

    Cetina, C. [Nova Research, Inc., Alexandria, VA 22308 (United States)], E-mail: Catalina.Cetina@nrl.navy.mil; Grabowski, K.S.; Knies, D.L. [Naval Research Laboratory, Washington, DC 20375 (United States); Demoranville, L.T. [University of Maryland, College Park, MD 20742 (United States)

    2008-12-15

    A wide variety of elements present in solar wind were collected during a 2-year space flight by the NASA Genesis Discovery mission. The high-value Genesis samples are presently analyzed by a few groups using SIMS and other techniques. For some of the more challenging measurements a combined SIMS-AMS facility may provide the advantages of accelerator mass spectrometry (AMS) to SIMS analysis, including molecular fragmentation and low-background detection. Initial results from simulating standards are presented here, demonstrating the capability of the system for this kind of surface analysis. Measurements were performed on internally produced standards consisting of Si wafers implanted with 10{sup 14} atoms/cm{sup 2} doses of Mg, Ti, Fe, Ni, Cu, and Zn. At the ion source stage, crater-edge effects were filtered by position gating, while at the spectrograph focal plane, possible interferences were rejected by coincidence position-energy detection. Thus, SIMS-like depth profiles were obtained and will be used for estimating system-specific relative sensitivity factors.

  13. Ocean Profile Measurements During the Seasonal Ice Zone Reconnaissance Surveys Ocean Profiles

    Science.gov (United States)

    2017-01-01

    greater availability of synoptic snapshots of environmental properties over extended ranges. RELATED PROJECTS See Table 1 of the report for related...Guard mission are described by Hyles (2014). Our measurements are illustrated in Figure 1. Specifically, the core elements ( Table 1) are aircraft...modeling components (Schweiger et al.) will tie the SIZRS observations together. Other collaborating projects ( Table 2) have come forward to participate

  14. Quasi-quadrature interferometer for plasma density radial profile measurements

    International Nuclear Information System (INIS)

    Lowenthal, D.D.; Hoffman, A.L.

    1979-01-01

    A cw Mach Zehnder multichannel interferometer has been developed to measure time-dependent fractional fringe shifts with an accuracy of one-fortieth fringe. The design is quasi-quadrature in that known phase shifts, introduced in the reference beam, are time multiplexed with the normal reference beam. This technique requires only one detector per interferometer channel as compared to two detectors for most quadrature designs. The quadrature information makes the sense of density changes unambiguous, it automatically calibrates the instrument during the plasma event, and it makes fringe shift measurements virtually independent of fringe contrast fluctuations caused by plasma refractive and/or absorptive effects. The interferometer optical design is novel in that the electro-optic crystal used to introduce the 90 0 phase shifts is located in the common 2-mm-diam HeNe entrance beam to the interferometer, by exploiting polarization techniques, rather than in the expanded 1--2-cm reference beam itself. This arrangement greatly reduces the size, cost, and high-voltage requirements for the phase modulating crystal

  15. Surface moisture measurement system hardware acceptance test report

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, G.A., Westinghouse Hanford

    1996-05-28

    This document summarizes the results of the hardware acceptance test for the Surface Moisture Measurement System (SMMS). This test verified that the mechanical and electrical features of the SMMS functioned as designed and that the unit is ready for field service. The bulk of hardware testing was performed at the 306E Facility in the 300 Area and the Fuels and Materials Examination Facility in the 400 Area. The SMMS was developed primarily in support of Tank Waste Remediation System (TWRS) Safety Programs for moisture measurement in organic and ferrocyanide watch list tanks.

  16. System design description for surface moisture measurement system (SMMS)

    Energy Technology Data Exchange (ETDEWEB)

    Vargo, G.F.

    1996-09-23

    The SMMS has been developed to measure moisture in the top few centimeters of tank waste. The SMMS development was initiated by the preliminary findings of SAR-033, and does not necessarily fulfill any established DQO. After the SAR-033 is released, if no significant changes are made, moisture measurements in the organic waste tanks will rapidly become a DQO. The SMMS was designed to be installed in any 4 inch or larger riser, and to allow maximum adjustability for riser lengths, and is used to deploy a sensor package on the waste surface within a 6 foot radius about the azimuth. The first sensor package will be a neutron probe.

  17. Surface moisture measurement system hardware acceptance test procedure

    International Nuclear Information System (INIS)

    Ritter, G.A.

    1996-01-01

    The purpose of this acceptance test procedure is to verify that the mechanical and electrical features of the Surface Moisture Measurement System are operating as designed and that the unit is ready for field service. This procedure will be used in conjunction with a software acceptance test procedure, which addresses testing of software and electrical features not addressed in this document. Hardware testing will be performed at the 306E Facility in the 300 Area and the Fuels and Materials Examination Facility in the 400 Area. These systems were developed primarily in support of Tank Waste Remediation System (TWRS) Safety Programs for moisture measurement in organic and ferrocyanide watch list tanks

  18. Actual evaporation estimation from infrared measurement of soil surface temperature

    Directory of Open Access Journals (Sweden)

    Davide Pognant

    2013-09-01

    Full Text Available Within the hydrological cycle, actual evaporation represents the second most important process in terms of volumes of water transported, second only to the precipitation phenomena. Several methods for the estimation of the Ea were proposed by researchers in scientific literature, but the estimation of the Ea from potential evapotranspiration often requires the knowledge of hard-to-find parameters (e.g.: vegetation morphology, vegetation cover, interception of rainfall by the canopy, evaporation from the canopy surface and uptake of water by plant roots and many existing database are characterized by missing or incomplete information that leads to a rough estimation of the actual evaporation amount. Starting from the above considerations, the aim of this study is to develop and validate a method for the estimation of the Ea based on two steps: i the potential evaporation estimation by using the meteorological data (i.e. Penman-Monteith; ii application of a correction factor based on the infrared soil surface temperature measurements. The dataset used in this study were collected during two measurement campaigns conducted both in a plain testing site (Grugliasco, Italy, and in a mountain South-East facing slope (Cogne, Italy. During those periods, hourly measurement of air temperature, wind speed, infrared surface temperature, soil heat flux, and soil water content were collected. Results from the dataset collected in the two testing sites show a good agreement between the proposed method and reference methods used for the Ea estimation.

  19. The role of probe oxide in local surface conductivity measurements

    Science.gov (United States)

    Barnett, C. J.; Kryvchenkova, O.; Wilson, L. S. J.; Maffeis, T. G. G.; Kalna, K.; Cobley, R. J.

    2015-05-01

    Local probe methods can be used to measure nanoscale surface conductivity, but some techniques including nanoscale four point probe rely on at least two of the probes forming the same low resistivity non-rectifying contact to the sample. Here, the role of probe shank oxide has been examined by carrying out contact and non-contact I V measurements on GaAs when the probe oxide has been controllably reduced, both experimentally and in simulation. In contact, the barrier height is pinned but the barrier shape changes with probe shank oxide dimensions. In non-contact measurements, the oxide modifies the electrostatic interaction inducing a quantum dot that alters the tunneling behavior. For both, the contact resistance change is dependent on polarity, which violates the assumption required for four point probe to remove probe contact resistance from the measured conductivity. This has implications for all nanoscale surface probe measurements and macroscopic four point probe, both in air and vacuum, where the role of probe oxide contamination is not well understood.

  20. Holographic otoscope for nanodisplacement measurements of surfaces under dynamic excitation.

    Science.gov (United States)

    Flores-Moreno, J M; Furlong, Cosme; Rosowski, John J; Harrington, Ellery; Cheng, Jeffrey T; Scarpino, C; Santoyo, F Mendoza

    2011-01-01

    We describe a novel holographic otoscope system for measuring nanodisplacements of objects subjected to dynamic excitation. Such measurements are necessary to quantify the mechanical deformation of surfaces in mechanics, acoustics, electronics, biology, and many other fields. In particular, we are interested in measuring the sound-induced motion of biological samples, such as an eardrum. Our holographic otoscope system consists of laser illumination delivery (IS), optical head (OH), and image processing computer (IP) systems. The IS delivers the object beam (OB) and the reference beam (RB) to the OH. The backscattered light coming from the object illuminated by the OB interferes with the RB at the camera sensor plane to be digitally recorded as a hologram. The hologram is processed by the IP using the Fresnel numerical reconstruction algorithm, where the focal plane can be selected freely. Our holographic otoscope system is currently deployed in a clinic, and is packaged in a custom design. It is mounted in a mechatronic positioning system to increase its maneuverability degrees to be conveniently positioned in front of the object to be measured. We present representative results highlighting the versatility of our system to measure deformations of complex elastic surfaces in the wavelength scale including a copper foil membrane and postmortem tympanic membrane. SCANNING 33: 342-352, 2011. © 2011 Wiley Periodicals, Inc. Copyright © 2011 Wiley Periodicals, Inc.

  1. In-situ NO and NO2 profiles measured onboard passenger aircraft over Frankfurt airport in Germany

    Science.gov (United States)

    Berkes, Florian; Houben, Norbert; Blomel, Torben; Tappertzhofen, Marlon; Volz-Thomas, Andreas; Petzold, Andreas

    2017-04-01

    NOx (sum of NO and NO2) play a central role in atmospheric chemistry related to ozone and oxidation capacity (OH and NO3 radicals). The most important sources of NOx in the upper troposphere are lightning, and transport from the boundary layer (combustion processes, from biomass burning, agriculture, and industry/transport/aircraft emissions). In-situ measurements of NOx from the upper troposphere and lower stratosphere (UTLS) down to the surface are rare, but important for understanding the local photochemistry and for the assessment of the impact of aviation on the budgets of greenhouse gases such as ozone. The European Research Infrastructure IAGOS (In-service Aircraft for a Global Observing System) operates a global-scale monitoring system for atmospheric temperature, trace gases, aerosols and clouds at high spatial resolution by passenger aircraft. The IAGOS NOx instrument is designed for the autonomous measurement of nitrogen oxides over serval months. The measurement principle is based on the well-established chemiluminescence technique, using one channel with sequential measurements of NO and NOx every 50 s. Here, we present vertical profiles of nitrogen oxides from the UTLS down to the surface for day and night time conditions obtained over 12 months in 2015 and 2016. The analysis focuses mainly on Europe, the region with the largest amount of profiles. Other regions (North America, South America and East Asia) will also be discussed. Typically, NO and NO2 varies in the low ppt range in the UT, slightly increasing towards the pressure altitude of 200 hPa. Down to the surface, the values of NO and of NO2 increase up to several ppb. These profiles combined with in-situ water vapor and cloud parameters will be valuable for validation of model and of satellite data in the future.

  2. Using IR-measured soil surface temperatures to estimate hydraulic properties of the top soil layer

    Science.gov (United States)

    Steenpass, Christian; Vanderborght, Jan; Herbst, Michael; Simunek, Jirka; Vereecken, Harry

    2010-05-01

    The temporal and spatial development of soil surface temperatures (SST) depends on water availability in the near-surface soil layer. Since the soil loses latent heat during evaporation and water available for evaporation depends on soil hydraulic properties (SHP), the temporal variability of SST should contain information about the near-surface SHP. This study was conducted to investigate the information content of soil surface temperatures for estimation of soil hydraulic properties and their uncertainties, and to determine the effect of soil tillage on near-surface SHP. A hydrological model (HYDRUS-1D) coupled with a global optimizer (DREAM) was used to inversely estimate the van Genuchten-Mualem parameters of SHP from infra-red measured SST and TDR-measured water contents. The general applicability of this approach was tested using synthetic data. The same approach was then applied to a real data set, which was collected during September 2008 in Selhausen, Germany. The synthetic data set was generated using HYDRUS-1D for the same initial and boundary conditions and measurement protocol as the real data set. Using synthetic and real data it was found that although estimated SHP are sensitive to SST, their estimates are relatively uncertain when only information about SST is used. These uncertainties can be reduced by additionally considering also measured soil water contents. A comparison of SHP determined in the laboratory on undisturbed soil samples with those estimated from SST and TDR data measured in a harrowed soil showed similar results for the deeper undisturbed soil and large differences for the harrowed part of the soil profile. This shows the important effect of soil tillage on soil hydraulic properties. Application of the method in the field to characterize the hydraulic properties of the upper soil layer may reduce the amount of needed in-soil measurements and therefore allows larger scale observations.

  3. Combined analysis of surface reflection imaging and vertical seismic profiling at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Daley, T.M.; Majer, E.L.; Karageorgi, E.

    1994-08-01

    This report presents results from surface and borehole seismic profiling performed by the Lawrence Berkeley Laboratory (LBL) on Yucca Mountain. This work was performed as part of the site characterization effort for the potential high-level nuclear waste repository. Their objective was to provide seismic imaging from the near surface (200 to 300 ft. depth) to the repository horizon and below, if possible. Among the issues addressed by this seismic imaging work are location and depth of fracturing and faulting, geologic identification of reflecting horizons, and spatial continuity of reflecting horizons. The authors believe their results are generally positive, with tome specific successes. This was the first attempt at this scale using modem seismic imaging techniques to determine geologic features on Yucca Mountain. The principle purpose of this report is to present the interpretation of the seismic reflection section in a geologic context. Three surface reflection profiles were acquired and processed as part of this study. Because of environmental concerns, all three lines were on preexisting roads. Line 1 crossed the mapped surface trace of the Ghost Dance fault and it was intended to study the dip and depth extent of the fault system. Line 2 was acquired along Drill Hole wash and was intended to help the ESF north ramp design activities. Line 3 was acquired along Yucca Crest and was designed to image geologic horizons which were thought to be less faulted along the ridge. Unfortunately, line 3 proved to have poor data quality, in part because of winds, poor field conditions and limited time. Their processing and interpretation efforts were focused on lines 1 and 2 and their associated VSP studies

  4. On the discrepancy in measurement of Q using surface waves and normal modes

    Science.gov (United States)

    Meschede, M.; Romanowicz, B. A.

    2012-12-01

    We revisit the decade-old unsolved problem of why measurements of the quality factor (Q) for fundamental mode propagating Rayleigh waves differs by up to 20% from that measured using normal modes, in the frequency band where both approaches are possible. Surface wave measurements consistently yield lower Q values than modes. Since it is unclear which measurement is more accurate, this is currently a limitation on the resolution of 1D average Q profiles in the Earth, compounded by the fact that the measurement bias may not only affect the region of the spectrum where both methods are available but every Q measurement that is based upon one or the other of the mentioned techniques. We investigate the effect of elastic focussing and defocussing on long time series using a spectral element method that we have shown to be accurate enough for the relevant period ranges and the necessarily long time series. While previous investigations are based upon approximate methods that are only valid for smooth 3D models and weak heterogeneities, the SEM allows us to estimate the effect of more realistic distributions of heterogeneities on amplitude measurements, and therefore Q. Our investigations show a bias towards lower Q in the first arriving surface wave trains and a bias towards higher Q in later arrivals which could explain the mode surface-wave discrepancy. Heuristically this can be explained by the fact that energy that has been scattered off the great circle path is brought back into the great circle after multiple-orbits, leading to increased amplitude in late arrivals. Further we reinvestigate the effects of noise that predominantly influences the later part of the seismogram, the effect of post-processing as well as mode amplitude modulations that could potentially bias the measurements. We plan to present preliminary results on applying our insights to debias real data and reduce the error bounds on 1D Q models from normal modes and surface waves.

  5. Design of an O-mode frequency modulated reflectometry system for the measurement of Alborz Tokamak plasma density profile

    Energy Technology Data Exchange (ETDEWEB)

    Koohestani, Saeideh [Department of Energy Engineering and physics, Amirkabir University of Technology, Tehran, 15875-4413, Islamic Republic of Iran (Iran, Islamic Republic of); Amrollahi, Reza, E-mail: amrollahi@aut.ac.ir [Department of Energy Engineering and physics, Amirkabir University of Technology, Tehran, 15875-4413, Islamic Republic of Iran (Iran, Islamic Republic of); Moradi, Gholamreza [Department of Electrical Engineering, Amirkabir University of Technology, Tehran, 15875-4413, Islamic Republic of Iran (Iran, Islamic Republic of)

    2016-12-15

    Reflectometry is a common method for plasma diagnostic, in which microwaves are launched into the plasma and reflected at the critical surfaces. Comparing the reflected microwave signals with the launched waves would give rise to the plasma density profiles. In the present study, an ordinary mode (O-mode) frequency modulation (FM) reflectometry system has been designed for the electron density profile measurement of the Alborz Tokamak plasma. This system has been considered to operate at K-band (18–26.5 GHz) frequency range and scan the frequency band between 18 to 26 GHz in 40 μS. The density profile from major radius r = 47.9–51.55 cm can be measured in Alborz Tokamak plasma. Based on the Alborz Tokamak operational conditions, the characteristic frequencies, and some dimensional limitations, all parts of reflectometer have been designed so that an appropriate efficiency with minimum attenuation, especially in transmitting/receiving system would be achieved. A dual antenna and an oversized waveguide of X-band (8–12 GHz) for transmitting and receiving purposes and a balanced detector for absolute phase determination have been utilized. The details of the Alborz Tokamak FM reflectometry components focusing on the antenna and waveguide design and mounting are described in this paper. Additionally, the procedure of plasma profile reconstruction using the system output signal is discussed. This system uses signal phase shift to determine the position of the cutoff layer.

  6. CONTACT ANGLE MEASUREMENT OF DENTAL RESTORATIVE MATERIALS BY DROP PROFILE IMAGE ANALYSIS

    OpenAIRE

    M. Rinastiti, H. D. K. Yulianto dan

    2014-01-01

    The capability of initial microbial adhesion to dental restorative composites surface is influenced by the surface wettability of the materials. The common method to evaluate surface wettability of materials is contact angle measurement. The existing conventional method to measure contact angle is by means of a contact angle (CA)-Goniometer device, which is less practically applicable in clinical circumstances. Therefore, a more practical and applicable method is needed to measure contact ang...

  7. Composition and structure of Si-doped NiTi with a complex surface profile

    Science.gov (United States)

    Slabodchikov, Vladimir A.; Ovchinnikov, Stanislav V.; Kuznetsov, Vladimir M.

    2017-12-01

    The paper presents Auger spectroscopy and electron microscopy data on the elemental composition and structure of NiTi specimens with blind holes doped with Si through plasma immersion ion implantation. The data demonstrate how silicon is distributed through the depth of NiTi from its front surface and along the side of its hole. The upper layer formed upon treatment is shown to be amorphous, and its thickness measuring several tens of nanometers is about two times larger on the side surface of the hole than on the front surface.

  8. Development of ultrasonic velocity profile method for flow rate measurements of power plant (effect of measurement volume on turbulent flow measurement)

    International Nuclear Information System (INIS)

    Hiroshige, Kikura; Gentaro, Yamanaka; Tsuyoshi, Taishi; Masanori, Aritomi; Yasushi, Takeda; Michitsugu, Mori

    2001-01-01

    Ultrasonic Velocity Profile method has many advantages for flow rate measurement of power plant over the conventional flow measurement methods, such as measurement of the instantaneous velocity profile along the measuring line and its applicability to opaque liquids. Furthermore, the method has an advantage of being non-intrusive. Hence, it is applicable to various flow conditions, although it requires a relatively large measurement volume. In this paper, the effects of the measurement volume on the mean velocity profile for flow rate measurements of power plant and the Reynolds stress measurement have been investigated for fully developed turbulent pipe flows in a vertical pipe. The results are then compared with data obtained by Direct Numerical Simulation (DNS). (authors)

  9. Measurement system of bubbly flow using ultrasonic velocity profile monitor and video data processing unit

    International Nuclear Information System (INIS)

    Aritomi, Masanori; Zhou, Shirong; Nakajima, Makoto; Takeda, Yasushi; Mori, Michitsugu; Yoshioka, Yuzuru.

    1996-01-01

    The authors have been developing a measurement system for bubbly flow in order to clarify its multi-dimensional flow characteristics and to offer a data base to validate numerical codes for multi-dimensional two-phase flow. In this paper, the measurement system combining an ultrasonic velocity profile monitor with a video data processing unit is proposed, which can measure simultaneously velocity profiles in both gas and liquid phases, a void fraction profile for bubbly flow in a channel, and an average bubble diameter and void fraction. Furthermore, the proposed measurement system is applied to measure flow characteristics of a bubbly countercurrent flow in a vertical rectangular channel to verify its capability. (author)

  10. Deposition of corrosion products from dowels on human dental root surfaces measured with proton microprobe technique

    Science.gov (United States)

    Brune, D.; Brunell, G.; Lindh, U.

    1982-06-01

    Distribution of copper, mercury and zinc on human teeth root surfaces adjacent to dowels of gold alloy or brass as well as dowels of brass in conjunction with an amalgam crown has been measured with a proton microprobe using PIXE techniques. Upper limits of the contents of gold and silver on the root surfaces were established. Pronounced concentration profiles of copper and zinc were observed on the root surfaces of teeth prepared with dowels of brass. The dowel of gold alloy revealed only zinc deposition. The major part of copper on the root surfaces is assumed to arise from corrosion of the dowels, and has been transported to the surface by diffusion through the dential tubuli. Zinc in the volume analysed is a constituent of dentin tissue as well as a corrosion product of the brass dowel. Part of the zinc level could also be ascribed to erosion of the zinc phosphate cement matrix. The volumes analysed were (25×25×25)μm 3. The levels of copper, mercury and zinc on the tooth root surfaces attained values up to about 200, 20 and 600 ppm, respectively.

  11. Diagnostic Profiles of Patients Differentially Failing Executive Functioning Measures.

    Science.gov (United States)

    Hammers, Dustin; Ramirez, Gabriela; Persad, Carol; Heidebrink, Judith; Barbas, Nancy; Giordani, Bruno

    2016-05-01

    Limited research exists to explain differential executive functioning impairment in clinical populations, particularly between the Wisconsin Card Sorting Task (WCST) and the Trail Making Test (TMT). The distribution of clinical diagnoses was examined in patients failing none, one, or both tasks, and executive task performance was compared among dementia-related diagnoses. Two hundred and sixty-six participants received evaluations through an Alzheimer's Disease Research Center, which included executive tasks. Dementia-related diagnoses were established through consensus. Chi-square analyses indicated that TMT failure, with or without WCST failure, possessed higher associations with dementia diagnoses. Repeated measures analysis of variance similarly indicated that participants with dementia, especially mild and moderate severity, performed worse on TMT. Executive dysfunction was observed in dementia-related diagnoses, and TMT failure was implicated in dementia in higher proportions than WCST impairment. Trail Making Test appears more sensitive than WCST for assessing executive impairment across diagnoses, especially when time and resources are limited in screening and clinical settings. © The Author(s) 2015.

  12. Smoothness of ozone profiles: analysis of 11 years of ozone sonde measurements at Sodankylä

    Directory of Open Access Journals (Sweden)

    V. F. Sofieva

    2004-09-01

    Full Text Available This paper discusses the smoothness of vertical profiles of ozone concentrations. We describe the smoothness of ozone profiles via a characteristic scale of the profile fluctuations. The characteristic scale was computed for 11-years (1989-1999 ozone sonde data at Sodankylä. Mean values of the characteristic scale were determined. They are ~1km in the troposphere and ~1.4km in the lower stratosphere (up to 25km. Only slight seasonal variations of these parameters are observed. The information about smoothness of ozone profiles is needed both in the instrumental design for defining the vertical resolution requirements and in the development of inversion algorithms from remote sensing measurements, in order to obtain the best accuracy in retrieved ozone profiles and sufficient resolution.

  13. Smoothness of ozone profiles: analysis of 11 years of ozone sonde measurements at Sodankylä

    Directory of Open Access Journals (Sweden)

    V. F. Sofieva

    2004-09-01

    Full Text Available This paper discusses the smoothness of vertical profiles of ozone concentrations. We describe the smoothness of ozone profiles via a characteristic scale of the profile fluctuations. The characteristic scale was computed for 11-years (1989-1999 ozone sonde data at Sodankylä. Mean values of the characteristic scale were determined. They are ~1km in the troposphere and ~1.4km in the lower stratosphere (up to 25km. Only slight seasonal variations of these parameters are observed.

    The information about smoothness of ozone profiles is needed both in the instrumental design for defining the vertical resolution requirements and in the development of inversion algorithms from remote sensing measurements, in order to obtain the best accuracy in retrieved ozone profiles and sufficient resolution.

  14. Fabrication of Micro-Optics Elements with Arbitrary Surface Profiles Based on One-Step Maskless Grayscale Lithography

    Directory of Open Access Journals (Sweden)

    Qinyuan Deng

    2017-10-01

    Full Text Available A maskless lithography method to realize the rapid and cost-effective fabrication of micro-optics elements with arbitrary surface profiles is reported. A digital micro-mirror device (DMD is applied to flexibly modulate that the exposure dose according to the surface profile of the structure to be fabricated. Due to the fact that not only the relationship between the grayscale levels of the DMD and the exposure dose on the surface of the photoresist, but also the dependence of the exposure depth on the exposure dose, deviate from a linear relationship arising from the DMD and photoresist, respectively, and cannot be systemically eliminated, complicated fabrication art and large fabrication error will results. A method of compensating the two nonlinear effects is proposed that can be used to accurately design the digital grayscale mask and ensure a precise control of the surface profile of the structure to be fabricated. To testify to the reliability of this approach, several typical array elements with a spherical surface, aspherical surface, and conic surface have been fabricated and tested. The root-mean-square (RMS between the test and design value of the surface height is about 0.1 μm. The proposed method of compensating the nonlinear effect in maskless lithography can be directly used to control the grayscale levels of the DMD for fabricating the structure with an arbitrary surface profile.

  15. Microwave radiometer to retrieve temperature profiles from the surface to the stratopause

    Directory of Open Access Journals (Sweden)

    O. Stähli

    2013-09-01

    Full Text Available TEMPERA (TEMPERature RAdiometer is a new ground-based radiometer which measures in a frequency range from 51–57 GHz radiation emitted by the atmosphere. With this instrument it is possible to measure temperature profiles from ground to about 50 km. This is the first ground-based instrument with the capability to retrieve temperature profiles simultaneously for the troposphere and stratosphere. The measurement is done with a filterbank in combination with a digital fast Fourier transform spectrometer. A hot load and a noise diode are used as stable calibration sources. The optics consist of an off-axis parabolic mirror to collect the sky radiation. Due to the Zeeman effect on the emission lines used, the maximum height for the temperature retrieval is about 50 km. The effect is apparent in the measured spectra. The performance of TEMPERA is validated by comparison with nearby radiosonde and satellite data from the Microwave Limb Sounder on the Aura satellite. In this paper we present the design and measurement method of the instrument followed by a description of the retrieval method, together with a validation of TEMPERA data over its first year, 2012.

  16. Influence of zirconia framework thickness on residual stress profile in veneering ceramic: measurement by hole-drilling.

    Science.gov (United States)

    Mainjot, Amélie K; Schajer, Gary S; Vanheusden, Alain J; Sadoun, Michaël J

    2012-04-01

    Framework design is reported to influence chipping in zirconia-based restorations, which is an important cause of failure of such restorations. Residual stress profile in the veneering ceramic after the manufacturing process is an important predictive factor of the mechanical behavior of the material. The objective of this study is to investigate the influence of framework thickness on the stress profile measured in zirconia-based structures. The stress profile was measured with the hole-drilling method in bilayered disc samples of 20mm diameter with a 1.5 mm thick veneering ceramic layer. Six different framework thicknesses from 0.5 mm to 3 mm were studied. Two different cooling procedures were also investigated. Compressive stresses were observed in the surface, and tensile stresses in the depth of most of the samples. The slow cooling procedure was found to promote the development of interior tensile stresses, except for the sample with a 3mm thick framework. With the tempering procedure, samples with a 1.5 mm thick framework exhibited the most favorable stress profile, while thicker and thinner frameworks exhibited respectively in surface or interior tensile stresses. The measurements performed highlight the importance of framework thickness, which determine the nature of stresses and can explain clinical failures encountered, especially with thin frameworks. The adequate ratio between veneering ceramic and zirconia is hard to define, restricting the range of indications of zirconia-based restorations until a better understanding of such a delicate veneering process is achieved. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  17. Use of dispersive effects for density profile reconstruction from pulse radar reflectometry measurements alone

    International Nuclear Information System (INIS)

    Hacquin, S.; Heuraux, S.; Colin, M.; Leclert, G.

    2000-01-01

    Reflectometry deduces the density profiles from the time of flight measurements for different frequencies of the probing wave. Pulse radar reflectometry allows the time of flight measurements at only a few discrete frequencies (typically 10 frequencies), which can lead to bad profile reconstruction. In order to improve the profile determination, it is proposed to use a dispersive effect of higher order, namely the pulse broadening. It is shown that usual methods of profile reconstruction are then improved. Particular attention is paid to the initialization problem, which is crucial in O-mode reflectometry. Initialization methods that use only reflectometry measurements have been developed. The sensitivity of each method to the measurement errors is discussed. Errors due to density fluctuations have been investigated numerically. For density fluctuations with moderate amplitude, the time of flight can be significantly modified whereas the pulse broadening is mostly unchanged. It is shown that, even with significant errors (10% on the time of flight, up to 40% on the pulse broadening) the profile initialization can be improved by using both time of flight and optimal length. The density profile is then reconstructed with an acceptable accuracy. (author)

  18. High resolution measurements and modeling of auroral hydrogen emission line profiles

    Directory of Open Access Journals (Sweden)

    B. S. Lanchester

    2003-07-01

    Full Text Available Measurements in the visible wavelength range at high spectral resolution (1.3 Å have been made at Longyearbyen, Svalbard (15.8 E,78.2 N during an interval of intense proton precipitation. The shape and Doppler shift of hydrogen Balmer beta line profiles have been compared with model line profiles, using as input ion energy spectra from almost coincident passes of the FAST and DMSP spacecraft. The comparison shows that the simulation contains the important physical processes that produce the profiles, and confirms that measured changes in the shape and peak wave-length of the hydrogen profiles are the result of changing energy input. This combination of high resolution measurements with modeling provides a method of estimating the incoming energy and changes in flux of precipitating protons over Svalbard, for given energy and pitch-angle distributions. Whereas for electron precipitation, information on the incident particles is derived from brightness and brightness ratios which require at least two spectral windows, for proton precipitation the Doppler profile of resulting hydrogen emission is directly related to the energy and energy flux of the incident energetic protons and can be used to gather information about the source region. As well as the expected Doppler shift to shorter wavelengths, the measured profiles have a significant red-shifted component, the result of upward flowing emitting hydrogen atoms.Key words. Ionosphere (auroral ionosphere; particle precipitation – Magnetospheric physics (auroral phenomena

  19. High resolution measurements and modeling of auroral hydrogen emission line profiles

    Directory of Open Access Journals (Sweden)

    B. S. Lanchester

    Full Text Available Measurements in the visible wavelength range at high spectral resolution (1.3 Å have been made at Longyearbyen, Svalbard (15.8 E,78.2 N during an interval of intense proton precipitation. The shape and Doppler shift of hydrogen Balmer beta line profiles have been compared with model line profiles, using as input ion energy spectra from almost coincident passes of the FAST and DMSP spacecraft. The comparison shows that the simulation contains the important physical processes that produce the profiles, and confirms that measured changes in the shape and peak wave-length of the hydrogen profiles are the result of changing energy input. This combination of high resolution measurements with modeling provides a method of estimating the incoming energy and changes in flux of precipitating protons over Svalbard, for given energy and pitch-angle distributions. Whereas for electron precipitation, information on the incident particles is derived from brightness and brightness ratios which require at least two spectral windows, for proton precipitation the Doppler profile of resulting hydrogen emission is directly related to the energy and energy flux of the incident energetic protons and can be used to gather information about the source region. As well as the expected Doppler shift to shorter wavelengths, the measured profiles have a significant red-shifted component, the result of upward flowing emitting hydrogen atoms.

    Key words. Ionosphere (auroral ionosphere; particle precipitation – Magnetospheric physics (auroral phenomena

  20. The evaporative fraction as a measure of surface energy partitioning

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, W.E. [Pacific Northwest Lab., Richland, WA (United States); Cuenca, R.H. [Oregon State Univ., Corvallis, OR (United States)

    1990-12-31

    The evaporative fraction is a ratio that expresses the proportion of turbulent flux energy over land surfaces devoted to evaporation and transpiration (evapotranspiration). It has been used to characterize the energy partition over land surfaces and has potential for inferring daily energy balance information based on mid-day remote sensing measurements. The HAPEX-MOBILHY program`s SAMER system provided surface energy balance data over a range of agricultural crops and soil types. The databases from this large-scale field experiment was analyzed for the purpose of studying the behavior and daylight stability of the evaporative fraction in both ideal and general meteorological conditions. Strong linear relations were found to exist between the mid-day evaporative fraction and the daylight mean evaporative fraction. Statistical tests however rejected the hypothesis that the two quantities were equal. The relations between the evaporative fraction and the surface soil moisture as well as soil moisture in the complete vegetation root zone were also explored.

  1. The evaporative fraction as a measure of surface energy partitioning

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, W.E. (Pacific Northwest Lab., Richland, WA (United States)); Cuenca, R.H. (Oregon State Univ., Corvallis, OR (United States))

    1990-01-01

    The evaporative fraction is a ratio that expresses the proportion of turbulent flux energy over land surfaces devoted to evaporation and transpiration (evapotranspiration). It has been used to characterize the energy partition over land surfaces and has potential for inferring daily energy balance information based on mid-day remote sensing measurements. The HAPEX-MOBILHY program's SAMER system provided surface energy balance data over a range of agricultural crops and soil types. The databases from this large-scale field experiment was analyzed for the purpose of studying the behavior and daylight stability of the evaporative fraction in both ideal and general meteorological conditions. Strong linear relations were found to exist between the mid-day evaporative fraction and the daylight mean evaporative fraction. Statistical tests however rejected the hypothesis that the two quantities were equal. The relations between the evaporative fraction and the surface soil moisture as well as soil moisture in the complete vegetation root zone were also explored.

  2. Relative vegetation profiles in a Neotropical forest: comparison of lidar instrumentation and field-based measurements

    Science.gov (United States)

    Sullivan, F. B.; Palace, M. W.; Ducey, M.; Czarnecki, C.; Zanin Shimbo, J.; Mota e Silva, J.

    2012-12-01

    Tropical forests are considered to be some of the most structurally complex forests in the world. Understanding vegetation height structure in these forests can aid in understanding the spatial temporal components of disturbance, from blowdowns to gap dynamics. Vegetation profiles can be used to better estimate carbon storage and flux across the landscape. Using light detection and ranging (lidar) data collected at La Selva, Costa Rica from four instruments (three airborne, one terrestrial) at four times since 2005, and field data collected in January 2012, we generated relative vegetation profiles for twenty plots in La Selva. Relative vegetation profiles were derived from lidar data by accounting for obscured plant material through a log transformation of the cumulative proportion of observations (percent canopy closure). Profiles were derived from field data using two different sets of allometric equations describing crown shape and tree height. We conducted a cluster analysis on similarity matrices developed in R (version 2.14.1) using three different metrics (sum of squares, Kullback-Leibler divergence, Kolmogorov-Smirnov D statistic) and identified general similarity between lidar profiles. Results were consistent across each of the three similarity metrics. Three distinct clusters were found, with profiles from three airborne lidar instruments, two profiles from a terrestrial lidar instrument, and profiles derived from field data forming the clusters. Our results indicate that although estimating lidar relative vegetation profiles from field data was not possible, terrestrial lidar relative vegetation profiles are generally similar to airborne relative vegetation profiles. Given the rapidity and repeatability of terrestrial lidar measurements, these results show promise for terrestrial lidar instruments to collect plot-specific data on forest structure and vertical distribution of plant material. Furthermore, identifying relationships between terrestrial and

  3. Airborne Spectral Measurements of Surface-Atmosphere Anisotropy for Several Surfaces and Ecosystem over Southern Africa

    Science.gov (United States)

    Gatebe, C. K.; King, M. D.; Tsay, S.; Arnold, G. T.; Li, J. Y.

    2001-12-01

    The Cloud Absorption Radiometer (CAR) was flown aboard the University of Washington Convair CV-580 research aircraft and took measurements on 23 flights between August 15 and September 16. On 12 of those flights, BRF measurements were obtained over different natural surfaces and ecosystem in southern Africa. The BRF measurements were done to characterize surface anisotropy in support of SAFARI 2000 science objectives principally to validate products from NASA's EOS satellites, and to parameterize and validate BRF models. In this paper we present results of BRFs taken over two EOS validation sites: Skukuza tower, South Africa (25.0 oS, 31.5 oE) and Mongu tower, Zambia (15.4 oS, 23.3 oE). Additional sites are also considered and include, Maun tower, Botswana (20.0 oS, 23.5 oE), Sowa Pan, Botswana (20.6 oS, 26.2 oE) and Etosha Pan, Namibia (19.0 oS, 16.0 oE). The CAR is capable of measuring scattered light in fourteen spectral bands. The scan mirror, rotating at 100 rpm, directs the light into a Dall-Kirkham telescope where the beam is split into nine paths. Eight light beams pass through beam splitters, dichroics, and lenses to individual detectors (0.34-1.27 μ m), and finally are registered by eight data channels. They are sampled simultaneously and continuously. The ninth beam passes through a spinning filter wheel to an InSb detector cooled by a Stirling cycle cooler. Signals registered by the ninth data channel are selected from among six spectral channels (1.55-2.30 μ m). The filter wheel can either cycle through all six spectral bands at a prescribed interval (usually changing filter every fifth scan line), or lock onto any one of the six spectral bands and sample it continuously. To measure the BRF of the surface-atmosphere system, the University of Washington CV-580 had to bank at a comfortable roll angle of ~20 o and fly in a circle about 3 km in diameter above the surface for roughly two minutes. Replicated observations (multiple circular orbits) were

  4. Surface Current Measurements In Terra Nova Bay By Hf Radar

    Science.gov (United States)

    Flocco, D.; Falco, P.; Wadhams, P.; Spezie, G.

    We present the preliminary results of a field experiment carried out within frame- work of the CLIMA project of the Italian National Programme for Antarctic Research (PNRA) and in cooperation with the Scott Polar Research Institute of Cambridge. Dur- ing the second period (02/12/1999-23/01/2000) of the XV Italian expedition a coastal radar was used to characterize the current field in the area of Terra Nova Bay (TNB). One of the aims of the CLIMA (Climatic Long-term Interactions for the Mass balance in Antarctica) project is to determine the role of the polynya in the sea ice mass bal- ance, water structure and local climate. The OSCR-II experiment was planned in order to provide surface current measurements in the area of TNB polynya, one of the most important coastal polynya of the Ross Sea. OSCR (Ocean Surface Current Radar) is a shore based, remote sensing system designed to measure sea surface currents in coastal waters. Two radar sites (a master and a slave) provide with radial current mea- surements; data combined from both sites yield the total current vector. Unfortunately the master and slave stations did not work together throughout the whole period of the experiment. A description of the experiment and a discussion of the results, will be proposed.

  5. Determining water sources in the boundary layer from tall tower profiles of water vapor and surface water isotope ratios after a snowstorm in Colorado

    Directory of Open Access Journals (Sweden)

    D. Noone

    2013-02-01

    Full Text Available The D/H isotope ratio is used to attribute boundary layer humidity changes to the set of contributing fluxes for a case following a snowstorm in which a snow pack of about 10 cm vanished. Profiles of H2O and CO2 mixing ratio, D/H isotope ratio, and several thermodynamic properties were measured from the surface to 300 m every 15 min during four winter days near Boulder, Colorado. Coeval analysis of the D/H ratios and CO2 concentrations find these two variables to be complementary with the former being sensitive to daytime surface fluxes and the latter particularly indicative of nocturnal surface sources. Together they capture evidence for strong vertical mixing during the day, weaker mixing by turbulent bursts and low level jets within the nocturnal stable boundary layer during the night, and frost formation in the morning. The profiles are generally not well described with a gradient mixing line analysis because D/H ratios of the end members (i.e., surface fluxes and the free troposphere evolve throughout the day which leads to large uncertainties in the estimate of the D/H ratio of surface water flux. A mass balance model is constructed for the snow pack, and constrained with observations to provide an optimal estimate of the partitioning of the surface water flux into contributions from sublimation, evaporation of melt water in the snow and evaporation from ponds. Results show that while vapor measurements are important in constraining surface fluxes, measurements of the source reservoirs (soil water, snow pack and standing liquid offer stronger constraint on the surface water balance. Measurements of surface water are therefore essential in developing observational programs that seek to use isotopic data for flux attribution.

  6. Measurements of solar and terrestrial heating and cooling rate profiles in Arctic and sub-tropic stratocumulus

    Science.gov (United States)

    Gottschalk, Matthias; Lauermann, Felix; Ehrlich, André; Siebert, Holger; Wendisch, Manfred

    2017-04-01

    Stratocumulus covers approximately 20 % (annually averaged) of the Earth's surface and thus strongly influences the atmospheric and surface radiative energy budget resulting in radiative cooling and heating effects. Globally, the solar cooling effect of the widespread sub-tropical stratocumulus dominates. However, in the Arctic the solar cloud albedo effect (cooling) is often smaller than the thermal-infrared greenhouse effect (warming), which is a result of the lower incoming solar radiation and the low cloud base height. Therefore, Arctic stratocumulus mostly warms the atmosphere and surface below the cloud. Additionally, different environmental conditions lead to differences between sub-tropical and Arctic stratocumulus. Broadband pyranometers and pyrgeometers will be used to measure heating and cooling rate profiles in and above stratocumulus. For this purpose two slowly moving platforms are used (helicopter and tethered balloon) in order to consider for the long response times of both broadband radiation sensors. Two new instrument packages are developed for the applied tethered balloon and helicopter platforms, which will be operated within Arctic and sub-tropical stratocumulus, respectively. In June 2017, the balloon will be launched from a sea ice floe north of 80 °N during the Arctic Balloon-borne profiling Experiment (ABEX) as part of (AC)3 (Arctic Amplification: Climate Relevant Atmospheric and Surface Processes and Feedback Mechanisms) Transregional Collaborative Research Center. The helicopter will sample sub-tropical stratocumulus over the Azores in July 2017.

  7. Surface temperature measurements of heterogeneous explosives by IR emission

    Energy Technology Data Exchange (ETDEWEB)

    Henson, B.F.; Funk, D.J.; Dickson, P.M.; Fugard, C.S.; Asay, B.W.

    1998-03-01

    The authors present measurements of the integrated IR emission (1--5 {micro}m) from both the heterogeneous explosive PBX 9501 and pure HMX at calibrated temperatures from 300 C to 2,500 C. The IR power emitted as a function of temperature is that expected of a black body, attenuated by a unique temperature independent constant which the authors report as the thermal emissivity. The authors have utilized this calibration of IR emission in measurements of the surface temperature from PBX 9501 subject to 1 GPa, two dimensional impact, and spontaneous ignition in unconfined cookoff. They demonstrate that the measurement of IR emission in this spectral region provides a temperature probe of sufficient sensitivity to resolve the thermal response from the solid explosive throughout the range of weak mechanical perturbation, prolonged heating to ignition, and combustion.

  8. Application of laser tracker technology for measuring optical surfaces

    Science.gov (United States)

    Zobrist, Tom L.

    The pages of this dissertation detail the development of an advanced metrology instrument for measuring large optical surfaces. The system is designed to accurately guide the fabrication of the Giant Magellan Telescope and future telescopes through loose-abrasive grinding. The instrument couples a commercial laser tracker with an advanced calibration technique and a set of external references to mitigate a number of error sources. The system is also required to work as a verification test for the GMT principal optical interferometric test of the polished mirror segment to corroborate the measurements in several low-order aberrations. A set of system performance goals were developed to ensure that the system will achieve these purposes. The design, analysis, calibration results, and measurement performance of the Laser Tracker Plus system are presented in this dissertation.

  9. Measurement of steep aspheric surfaces using an anamorphic probe

    International Nuclear Information System (INIS)

    Biswas, Amiya; Coupland, Jeremy

    2008-01-01

    Synthetic aperture interferometry has been previously proposed as a possible in-process method to measure aspheric form (R. Tomlinson, Appl. Opt.42, 701, 2003.APOPAI0003-693510.1364/AO.42.000701). Preliminary demonstration utilized a scanning probe consisting of a pair of bare single mode fibers to perform source and receive functions. It was found that this probe did not have sufficient numerical aperture (NA) to measure steep surfaces and that simply increasing the NA decreases the light gathering efficiency substantially. In this paper, we introduce supplementary optics to increase the NA, and the light gathering efficiency has been increased by adopting an anamorphic design. A spherical test optic of known form is measured to demonstrate the capability of the new probe design

  10. Measurement of steep aspheric surfaces using an anamorphic probe

    Science.gov (United States)

    Biswas, Amiya; Coupland, Jeremy

    2008-04-01

    Synthetic aperture interferometry has been previously proposed as a possible in-process method to measure aspheric form (R. Tomlinson, Appl. Opt.42, 701, 2003.APOPAI0003-693510.1364/AO.42.000701). Preliminary demonstration utilized a scanning probe consisting of a pair of bare single mode fibers to perform source and receive functions. It was found that this probe did not have sufficient numerical aperture (NA) to measure steep surfaces and that simply increasing the NA decreases the light gathering efficiency substantially. In this paper, we introduce supplementary optics to increase the NA, and the light gathering efficiency has been increased by adopting an anamorphic design. A spherical test optic of known form is measured to demonstrate the capability of the new probe design.

  11. Beam profile measurement of ES-200 using secondary electron emission monitor

    Directory of Open Access Journals (Sweden)

    E Ebrahimi Basabi

    2015-09-01

    Full Text Available Up to now, different designs have been introduced for measurement beam profile accelerators. Secondary electron emission monitors (SEM are one of these devices which have been used for this purpose. In this work, a SEM has been constructed to measure beam profile of ES-200 accelerator, a proton electrostatic accelerator which is installed at SBU. Profile grid for both planes designed with 16 wires which are insulated relative to each other. The particles with maximum energy of 200 keV and maximum current of 400 μA are stopped in copper wires. Each of the wires has an individual current-to-voltage amplifier. With a multiplexer, the analogue values are transported to an ADC. The ADCs are read out by a microcontroller and finally profile of beam shows by a user interface program

  12. Error Correction of Measured Unstructured Road Profiles Based on Accelerometer and Gyroscope Data

    Directory of Open Access Journals (Sweden)

    Jinhua Han

    2017-01-01

    Full Text Available This paper describes a noncontact acquisition system composed of several time synchronized laser height sensors, accelerometers, gyroscope, and so forth in order to collect the road profiles of vehicle riding on the unstructured roads. A method of correcting road profiles based on the accelerometer and gyroscope data is proposed to eliminate the adverse impacts of vehicle vibration and attitudes change. Because the power spectral density (PSD of gyro attitudes concentrates in the low frequency band, a method called frequency division is presented to divide the road profiles into two parts: high frequency part and low frequency part. The vibration error of road profiles is corrected by displacement data obtained through two times integration of measured acceleration data. After building the mathematical model between gyro attitudes and road profiles, the gyro attitudes signals are separated from low frequency road profile by the method of sliding block overlap based on correlation analysis. The accuracy and limitations of the system have been analyzed, and its validity has been verified by implementing the system on wheeled equipment for road profiles’ measuring of vehicle testing ground. The paper offers an accurate and practical approach to obtaining unstructured road profiles for road simulation test.

  13. Estimating regional methane surface fluxes: the relative importance of surface and GOSAT mole fraction measurements

    Directory of Open Access Journals (Sweden)

    A. Fraser

    2013-06-01

    Full Text Available We use an ensemble Kalman filter (EnKF, together with the GEOS-Chem chemistry transport model, to estimate regional monthly methane (CH4 fluxes for the period June 2009–December 2010 using proxy dry-air column-averaged mole fractions of methane (XCH4 from GOSAT (Greenhouse gases Observing SATellite and/or NOAA ESRL (Earth System Research Laboratory and CSIRO GASLAB (Global Atmospheric Sampling Laboratory CH4 surface mole fraction measurements. Global posterior estimates using GOSAT and/or surface measurements are between 510–516 Tg yr−1, which is less than, though within the uncertainty of, the prior global flux of 529 ± 25 Tg yr−1. We find larger differences between regional prior and posterior fluxes, with the largest changes in monthly emissions (75 Tg yr−1 occurring in Temperate Eurasia. In non-boreal regions the error reductions for inversions using the GOSAT data are at least three times larger (up to 45% than if only surface data are assimilated, a reflection of the greater spatial coverage of GOSAT, with the two exceptions of latitudes >60° associated with a data filter and over Europe where the surface network adequately describes fluxes on our model spatial and temporal grid. We use CarbonTracker and GEOS-Chem XCO2 model output to investigate model error on quantifying proxy GOSAT XCH4 (involving model XCO2 and inferring methane flux estimates from surface mole fraction data and show similar resulting fluxes, with differences reflecting initial differences in the proxy value. Using a series of observing system simulation experiments (OSSEs we characterize the posterior flux error introduced by non-uniform atmospheric sampling by GOSAT. We show that clear-sky measurements can theoretically reproduce fluxes within 10% of true values, with the exception of tropical regions where, due to a large seasonal cycle in the number of measurements because of clouds and aerosols, fluxes are within 15% of true fluxes. We evaluate our

  14. Measurements of flow velocity and temperature profile in a propane-oxygen combustion MHD channel

    International Nuclear Information System (INIS)

    Aoki, Yoshiaki; Kayukawa, Naoyuki; Yamazaki, Hatsuo

    1986-01-01

    In a propane-oxygen combustion MHD channel, experimental measurements were made of the plasma flow velocity by means of a cross-correlation function analysis and of the boundary-layer temperature-profile by a newly-devised light-polarization line-reversal method. The following results were obtained: the velocity decreased gradually, the temperature profile of the boundary layer varied appreciably as the magnitude of the externally applied magnetic field increased, and the temperature increased from Joule heating, making the boundary layer profile steeper. (author)

  15. On the effectiveness of surface assimilation in probabilistic nowcasts of planetary boundary layer profiles

    Science.gov (United States)

    Rostkier-Edelstein, Dorita; Hacker, Joshua

    2013-04-01

    Surface observations comprise a wide, non-expensive and reliable source of information about the state of the near-surface planetary boundary layer (PBL). Operational data assimilation systems have encountered several difficulties in effectively assimilating them, among others due to their local-scale representativeness, the transient coupling between the surface and the atmosphere aloft and the balance constraints usually used. A long-term goal of this work is to find an efficient system for probabilistic PBL nowcasting that can be employed wherever surface observations are present. Earlier work showed that surface observations can be an important source of information with a single column model (SCM) and an ensemble filter (EF). Here we extend that work to quantify the probabilistic skill of ensemble SCM predictions with a model including added complexity. We adopt a factor separation analysis to quantify the contribution of surface assimilation relative to that of selected model components (parameterized radiation and externally imposed horizontal advection) to the probabilistic skill of the system, and of any beneficial or detrimental interactions between them. To assess the real utility of the flow-dependent covariances estimated with the EF and of the SCM of the PBL we compare the skill of the SCM/EF system to that of a reference one based on climatological covariances and a 30-min persistence model. It consists of a dressing technique, whereby a deterministic 3D mesoscale forecast (e.g. from WRF model) is adjusted and dressed with uncertainty using a seasonal sample of mesoscale forecasts and surface forecast errors. Results show that assimilation of surface observations can improve deterministic and probabilistic profile predictions more significantly than major model improvements. Flow-dependent covariances estimated with the SCM/EF show clear advantage over the use of climatological covariances when the flow is characterized by wide variability, when

  16. The extent of temporal smearing in surface-temperature histories derived from borehole temperature measurements

    Science.gov (United States)

    Clow, G.D.

    1992-01-01

    The ability of borehole temperature data to resolve past climatic events is investigated using Backus-Gilbert inversion methods. Two experimental approaches are considered: (1) the data consist of a single borehole temperature profile, and (2) the data consist of climatically-induced temperature transients measured within a borehole during a monitoring experiment. The sensitivity of the data's resolving power to the vertical distribution of the measurements, temperature measurement errors, the inclusion of a local meteorological record, and the duration of a monitoring experiment, are investigated. The results can be used to help interpret existing surface temperature histories derived from borehole temperature data and to optimize future experiments for the detection of climatic signals. ?? 1992.

  17. Measuring and interpreting X-ray fluorescence from planetary surfaces.

    Science.gov (United States)

    Owens, Alan; Beckhoff, Burkhard; Fraser, George; Kolbe, Michael; Krumrey, Michael; Mantero, Alfonso; Mantler, Michael; Peacock, Anthony; Pia, Maria-Grazia; Pullan, Derek; Schneider, Uwe G; Ulm, Gerhard

    2008-11-15

    As part of a comprehensive study of X-ray emission from planetary surfaces and in particular the planet Mercury, we have measured fluorescent radiation from a number of planetary analog rock samples using monochromatized synchrotron radiation provided by the BESSY II electron storage ring. The experiments were carried out using a purpose built X-ray fluorescence (XRF) spectrometer chamber developed by the Physikalisch-Technische Bundesanstalt, Germany's national metrology institute. The XRF instrumentation is absolutely calibrated and allows for reference-free quantitation of rock sample composition, taking into account secondary photon- and electron-induced enhancement effects. The fluorescence data, in turn, have been used to validate a planetary fluorescence simulation tool based on the GEANT4 transport code. This simulation can be used as a mission analysis tool to predict the time-dependent orbital XRF spectral distributions from planetary surfaces throughout the mapping phase.

  18. Depth profile of In and As in Si measured by RBS with He and C ions

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Q.; Fang, Z. [Newcastle Univ., NSW (Australia). Dept. of Physics; Ophel, T.R. [Australian National Univ., Canberra, ACT (Australia). Dept. of Nuclear Physics

    1993-12-31

    The depth profile of As and In implanted into Si have been measured by RBS (Rutherford Backscattering Spectrometry) with 2 MeV He ions and 6 MeV C ions. Advantages of enhanced depth and mass resolution with C ions have been demonstrated over the conventional He RBS. More reliable information for the depth profile of In and As in Si has been obtained. 12 refs., 3 figs.

  19. Electrical properties of Titan's surface from Cassini RADAR scatterometer measurements

    Science.gov (United States)

    Wye, Lauren C.; Zebker, Howard A.; Ostro, Steven J.; West, Richard D.; Gim, Yonggyu; Lorenz, Ralph D.; The Cassini Radar Team

    2007-06-01

    albedo feature Shangri-La is best fit by a Hagfors model with a dielectric constant close to 2.4 and an rms slope near 9.5°. From the modeled backscatter curves, we find the average radar albedo in the same linear (SL) polarization to be near 0.34. We constrain the total-power albedo in order to compare the measurements with available groundbased radar results, which are typically obtained in both senses of circular polarization. We estimate an upper limit of 0.4 on the total-power albedo, a value that is significantly higher than the 0.21 total albedo value measured at 13 cm [Campbell, D., Black, G., Carter, L., Ostro, S., 2003. Science 302, 431-434]. This is consistent with a surface that has more small-scale structure and is thus more reflective at 2-cm than 13-cm. We compare results across overlapping observations and observe that the reduction and analysis are repeatable and consistent. We also confirm the strong correlations between radar and near-infrared images.

  20. Research on improved design of airfoil profiles based on the continuity of airfoil surface curvature of wind turbines

    DEFF Research Database (Denmark)

    Chen, Jin; Cheng, Jiangtao; Shen, Wenzhong

    2013-01-01

    Aerodynamic of airfoil performance is closely related to the continuity of its surface curvature, and airfoil profiles with a better aerodynamic performance plays an important role in the design of wind turbine. The surface curvature distribution along the chord direction and pressure distributio...

  1. Surface solar irradiance from SCIAMACHY measurements: algorithm and validation

    Directory of Open Access Journals (Sweden)

    P. Wang

    2011-05-01

    Full Text Available Broadband surface solar irradiances (SSI are, for the first time, derived from SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY satellite measurements. The retrieval algorithm, called FRESCO (Fast REtrieval Scheme for Clouds from the Oxygen A band SSI, is similar to the Heliosat method. In contrast to the standard Heliosat method, the cloud index is replaced by the effective cloud fraction derived from the FRESCO cloud algorithm. The MAGIC (Mesoscale Atmospheric Global Irradiance Code algorithm is used to calculate clear-sky SSI. The SCIAMACHY SSI product is validated against globally distributed BSRN (Baseline Surface Radiation Network measurements and compared with ISCCP-FD (International Satellite Cloud Climatology Project Flux Dataset surface shortwave downwelling fluxes (SDF. For one year of data in 2008, the mean difference between the instantaneous SCIAMACHY SSI and the hourly mean BSRN global irradiances is −4 W m−2 (−1 % with a standard deviation of 101 W m−2 (20 %. The mean difference between the globally monthly mean SCIAMACHY SSI and ISCCP-FD SDF is less than −12 W m−2 (−2 % for every month in 2006 and the standard deviation is 62 W m−2 (12 %. The correlation coefficient is 0.93 between SCIAMACHY SSI and BSRN global irradiances and is greater than 0.96 between SCIAMACHY SSI and ISCCP-FD SDF. The evaluation results suggest that the SCIAMACHY SSI product achieves similar mean bias error and root mean square error as the surface solar irradiances derived from polar orbiting satellites with higher spatial resolution.

  2. Measurement of the density profile of pure and seeded molecular beams by femtosecond ion imaging

    NARCIS (Netherlands)

    Meng, C.; Janssen, M.H.M.

    2015-01-01

    Here, we report on femtosecond ion imaging experiments to measure the density profile of a pulsed supersonic molecular beam. Ion images are measured for both a molecular beam and bulk gas under identical experimental conditions via femtosecond multiphoton ionization of Xe atoms. We report the

  3. Opto-thermal moisture content and moisture depth profile measurements in organic materials

    NARCIS (Netherlands)

    Xiao, P.; Guo, X.; Cui, Y.Y.; Imhof, R.; Bicanic, D.D.

    2004-01-01

    Opto-thermal transient emission radiometry(OTTER) is a infrared remote sensing technique, which has been successfully used in in vivo skin moisture content and skin moisture depth profiling measurements.In present paper, we extend this moisture content measurement capability to analyze the moisture

  4. Dysarthria Impact Profile: Development of a Scale to Measure Psychosocial Effects

    Science.gov (United States)

    Walshe, Margaret; Peach, Richard K.; Miller, Nick

    2009-01-01

    Background: The psychosocial impact of acquired dysarthria on the speaker is well recognized. To date, speech-and-language therapists have no instrument available to measure this construct. This has implications for outcome measurement and for planning intervention. This paper describes the Dysarthria Impact Profile (DIP), an instrument that has…

  5. Simultaneous measurements with 3D PIV and Acoustic Doppler Velocity Profiler

    NARCIS (Netherlands)

    Blanckaert, K.J.F.; McLelland, S.J.

    2009-01-01

    Simultaneous velocity measurements were taken using Particle Image Velocimetry (PIV) and an Acoustic Doppler Velocity Profiler (ADVP) in a sharp open-channel bend with an immobile gravel bed. The PIV measures 3D velocity vectors in a vertical plane (~40cm x 20cm) at a frequency of 7.5 Hz, whereas

  6. Airborne spectral measurements of surface-atmosphere anisotropy for several surfaces and ecosystems over southern Africa

    Science.gov (United States)

    Gatebe, Charles K.; King, Michael D.; Platnick, Steve; Arnold, G. Thomas; Vermote, Eric F.; Schmid, Beat

    2003-07-01

    The Cloud Absorption Radiometer (CAR) was flown aboard the University of Washington Convair CV-580 research aircraft during the Southern Africa Regional Science Initiative 2000 (SAFARI 2000) dry season campaign and obtained measurements of bidirectional reflectance distribution function (BRDF) for a variety of natural surfaces and ecosystems in southern Africa. To measure the BRDF of the surface-atmosphere system, the University of Washington CV-580 banked at a roll angle of ˜20° and flew circles about 3 km in diameter above the surface, taking approximately 2 min. Multiple circular orbits were acquired over selected surfaces so that average BRDFs could be acquired, smoothing out small-scale surface and atmospheric inhomogeneities. In this paper, we present results of BRDFs taken over two Earth Observing System (EOS) validation sites: Skukuza tower, South Africa (25.0°S, 31.5°E) and Mongu tower, Zambia (15.4°S, 23.3°E). Additional sites are discussed and include the Maun tower, Botswana (20.0°S, 23.6°E), Sua Pan, Botswana (20.6°S, 25.9°E), Etosha Pan, Namibia (19.0°S, 16.0°E), and marine stratocumulus clouds off the west coast of Namibia (20.5°S, 13.1°E). Results clearly show anisotropy in reflected solar radiation over the various surfaces types: savanna, salt pans, and cloud. The greatest anisotropy is observed over marine stratus clouds, which exhibit strong forward scattering as well as important water cloud scattering features such as the rainbow and glory. The BRDF over savanna is characterized by a distinct backscattering peak in the principal plane and shows directional and spectral variations. Over the pans, the BRDF is more enhanced in the backscattering plane than forward scattering plane and shows little directional variation.

  7. Constraining Saturn's interior density profile from precision gravity field measurement obtained during Grand Finale

    Science.gov (United States)

    Movshovitz, N.; Fortney, J. J.; Helled, R.; Hubbard, W. B.; Mankovich, C.; Thorngren, D.; Wahl, S. M.; Militzer, B.; Durante, D.

    2017-12-01

    The external gravity field of a planetary body is determined by the distribution of mass in its interior. Therefore, a measurement of the external field, properlyinterpreted, tells us about the interior density profile, ρ(r), which in turn can be used to constrain the composition in the interior and thereby learn about theformation mechanism of the planet. Recently, very high precision measurements of the gravity coefficients for Saturn have been made by the radio science instrument on the Cassini spacecraft during its Grand Finale orbits. The resulting coefficients come with an associated uncertainty. The task of matching a given density profile to a given set of gravity coefficients is relatively straightforward, but the question of how to best account for the uncertainty is not. In essentially all prior work on matching models to gravity field data inferences about planetary structure have rested on assumptions regarding the imperfectly known H/He equation of state and the assumption of an adiabatic interior. Here we wish to vastly expand the phase space of such calculations. We present a framework for describing all the possible interior density structures of a Jovian planet constrained by a given set of gravity coefficients and their associated uncertainties. Our approach is statistical. We produce a random sample of ρ(a) curves drawn from the underlying (and unknown) probability distribution of all curves, where ρ is the density on an interior level surface with equatorial radius a. Since the resulting set of density curves is a random sample, that is, curves appear with frequency proportional to the likelihood of their being consistent with the measured gravity, we can compute probability distributions for any quantity that is a function of ρ, such as central pressure, oblateness, core mass and radius, etc. Our approach is also Bayesian, in that it can utilize any prior assumptions about the planet's interior, as necessary, without being overly

  8. Methodology for extraction of space charge density profiles at nanoscale from Kelvin probe force microscopy measurements.

    Science.gov (United States)

    Villeneuve-Faure, C; Boudou, L; Makasheva, K; Teyssedre, G

    2017-12-15

    To understand the physical phenomena occurring at metal/dielectric interfaces, determination of the charge density profile at nanoscale is crucial. To deal with this issue, charges were injected applying a DC voltage on lateral Al-electrodes embedded in a SiN x thin dielectric layer. The surface potential induced by the injected charges was probed by Kelvin probe force microscopy (KPFM). It was found that the KPFM frequency mode is a better adapted method to probe accurately the charge profile. To extract the charge density profile from the surface potential two numerical approaches based on the solution to Poisson's equation for electrostatics were investigated: the second derivative model method, already reported in the literature, and a new 2D method based on the finite element method (FEM). Results highlight that the FEM is more robust to noise or artifacts in the case of a non-flat initial surface potential. Moreover, according to theoretical study the FEM appears to be a good candidate for determining charge density in dielectric films with thicknesses in the range from 10 nm to 10 μm. By applying this method, the charge density profile was determined at nanoscale, highlighting that the charge cloud remains close to the interface.

  9. Methodology for extraction of space charge density profiles at nanoscale from Kelvin probe force microscopy measurements

    Science.gov (United States)

    Villeneuve-Faure, C.; Boudou, L.; Makasheva, K.; Teyssedre, G.

    2017-12-01

    To understand the physical phenomena occurring at metal/dielectric interfaces, determination of the charge density profile at nanoscale is crucial. To deal with this issue, charges were injected applying a DC voltage on lateral Al-electrodes embedded in a SiN x thin dielectric layer. The surface potential induced by the injected charges was probed by Kelvin probe force microscopy (KPFM). It was found that the KPFM frequency mode is a better adapted method to probe accurately the charge profile. To extract the charge density profile from the surface potential two numerical approaches based on the solution to Poisson’s equation for electrostatics were investigated: the second derivative model method, already reported in the literature, and a new 2D method based on the finite element method (FEM). Results highlight that the FEM is more robust to noise or artifacts in the case of a non-flat initial surface potential. Moreover, according to theoretical study the FEM appears to be a good candidate for determining charge density in dielectric films with thicknesses in the range from 10 nm to 10 μm. By applying this method, the charge density profile was determined at nanoscale, highlighting that the charge cloud remains close to the interface.

  10. Improved Satellite Estimation of Near-Surface Humidity Using Vertical Water Vapor Profile Information

    Science.gov (United States)

    Tomita, H.; Hihara, T.; Kubota, M.

    2018-01-01

    Near-surface air-specific humidity is a key variable in the estimation of air-sea latent heat flux and evaporation from the ocean surface. An accurate estimation over the global ocean is required for studies on global climate, air-sea interactions, and water cycles. Current remote sensing techniques are problematic and a major source of errors for flux and evaporation. Here we propose a new method to estimate surface humidity using satellite microwave radiometer instruments, based on a new finding about the relationship between multichannel brightness temperatures measured by satellite sensors, surface humidity, and vertical moisture structure. Satellite estimations using the new method were compared with in situ observations to evaluate this method, confirming that it could significantly improve satellite estimations with high impact on satellite estimation of latent heat flux. We recommend the adoption of this method for any satellite microwave radiometer observations.

  11. Multi-Energy Soft X-ray Measurements of the Electron Temperature Profile

    Science.gov (United States)

    Tritz, K.; Clayton, D. J.; Stutman, D.; Bell, R. E.; Diallo, A.; Leblanc, B. P.; Podesta, M.; Sabbagh, S.; NSTX Team

    2013-10-01

    A novel analysis method using a neural network algorithm has been used to reconstruct the electron temperature profile for high power NSTX discharges with fast time resolution (> 10 kHz) using multi-energy soft X-ray (ME-SXR) arrays both alone and in combination with low time-resolution space-resolved spectroscopy and a single chord of line-integrated density. This fast profile reconstruction uses the measured electron temperature profile from the 60 Hz multipoint Thomson scattering (MPTS) diagnostic to train the neural network with the high time resolution ME-SXR data. Comparisons using cross-validation between the neural network reconstruction and the measured Te profiles from MPTS show agreement within 5% over the profile radius. The accuracy of the neural network reconstruction demonstrates the ability to use ME-SXR diagnostics for high time resolution electron temperature measurements, and will be available on both EAST and NSTX-U for studies of electron heat transport as well as other general studies including impurity/particle transport, ELM profile dynamics, and MHD. Work supported by DoE grant no. DE-FG02-09ER55012.

  12. A LIDAR-Based Tree Canopy Characterization under Simulated Uneven Road Condition: Advance in Tree Orchard Canopy Profile Measurement

    Directory of Open Access Journals (Sweden)

    Yue Shen

    2017-01-01

    Full Text Available In real outdoor canopy profile detection, the accuracy of a LIDAR scanner to measure canopy structure is affected by a potentially uneven road condition. The level of error associated with attitude angles from undulations in the ground surface can be reduced by developing appropriate correction algorithm. This paper proposes an offline attitude angle offset correction algorithm based on a 3D affine coordinate transformation. The validity of the correction algorithm is verified by conducting an indoor experiment. The experiment was conducted on an especially designed canopy profile measurement platform. During the experiment, an artificial tree and a tree-shaped carved board were continuously scanned at constant laser scanner travel speed and detection distances under simulated bumpy road conditions. Acquired LIDAR laser scanner raw data was processed offline by exceptionally developed MATLAB program. The obtained results before and after correction method show that the single attitude angle offset correction method is able to correct the distorted data points in tree-shaped carved board profile measurement, with a relative error of 5%, while the compound attitude angle offset correction method is effective to reduce the error associated with compound attitude angle deviation from the ideal scanner pose, with relative error of 7%.

  13. [Measurements of surface ocean carbon dioxide partial pressure during WOCE

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    This paper discusses the research progress of the second year of research under Measurement of Surface Ocean Carbon Dioxide Partial Pressure During WOCE'' and proposes to continue measurements of underway pCO[sub 2]. During most of the first year of this grant, our efforts to measure pCO[sub 2] on WOCE WHP legs were frustrated by ship problems. The R/V Knorr, which was originally scheduled to carry out the first work on WHP lines P19 and P16 in the southeastem Pacific during the 1990-91 austral summer, was delayed in the shipyard during her mid-life refit for more than a year. In the interim, the smaller R/V Thomas Washington, was pressed into service to carry out lower-latitude portions of WHP lines P16 and P17 during mid-1991 (TUNES Expedition). We installed and operated our underway chromatographic system on this expedition, even though space and manpower on this smaller vessel were limited and no one from our group would be aboard any of the 3 WHP expedition legs. The results for carbon dioxide and nitrous oxide are shown. A map of the cruise track is shown for each leg, marked with cumulative distance. Following each track is a figure showing the carbon dioxide and nitrous oxide results as a function of distance along this track. The results are plotted as dry-gas mole fractions (in ppm and ppb, respectively) in air and in gas equilibrated with surface seawater at a total pressure equal to the barometric pressure. The air data are plotted as a 10-point running mean, and appear as a roughly horizontal line. The seawater data are plotted as individual points, using a 5-point Gaussian smoother. Equal values Of xCO[sub 2] in air and surface seawater indicate air-sea equilibrium.

  14. Neutron activation analysis to the profile surface sediments from several sites on the Havana Bay

    International Nuclear Information System (INIS)

    Diaz Riso, O.; Gelen, A.; Lopez, N.; Gonzalez, H.; Manso, M.V.; Graciano, A.M.; Nogueira, C.A.; Beltran, J.; Soto, J.

    2003-01-01

    Instrumental neutron activation analysis (INAA) technique was employed to analyze the surface sediments from several sites on the Havana Bay, Cuba. Measurements of heavy and trace elements in the sediments are reported. The results show that the concentration of the elements is site dependent. The data suggest that an anthropogenic input into the bay from domestic sewage and industries occurred

  15. The Measurement and Interpretation of Surface Wave Group Arrival Times

    Science.gov (United States)

    Masters, G.; Kane, D.; Morrow, J.; Zhou, Y.; Tromp, J.

    2005-12-01

    We have recently developed an efficient technique for measuring the relative group arrival times of surface waves by using cross-correlation and cluster analysis of waveform envelope functions. Applying the analysis to minor arc Love and Rayleigh waves in the frequency band 7 to 35 mHz for all events over magnitude 5.5 results in a dataset of over 200,000 measurements at each frequency for long period Rayleigh waves (frequency less than 25 mHz) and about 100,000 measurements at the shorter periods. Analysis of transverse components results in about half as many Love wave measurements. Simple ray theory inversions of the relative arrival times for apparent group velocity produce maps which are accurate representations of the data (often over 90% variance reduction of the relative arrival times) and which show features strongly correlated with tectonics and crustal thickness. The apparent group velocity variations can be extremely large: 30% velocity variations for 20 mHz Rayleigh waves and 40% variations for 30 mHz Rayleigh waves and can have abrupt lateral changes. This raises the concern that non-ray theory effects could be important. Indeed, a recent analysis by Dahlen and Zhou (personal communication) suggests that the group arrival times should be a functions of both the group velocity AND the phase velocity. The simplest way to test the interpretation of the measurements is to perform the analysis on synthetic seismograms computed for a realistic model of the Earth. Here, we use the SEM with a model which incorporates realistic crust and mantle structure. We are currently computing synthetics for a suite of roughly 1000 events recorded globally that extend to a period of 18 seconds. We shall present the results of applying both ray-based and finite frequency inversions to the synthetic data as well as evaluating the effects of off path propagation at short periods using surface wave ray tracing.

  16. Measuring the surface roughness of geological rock surfaces in SAR data using fractal geometry

    Science.gov (United States)

    Ghafouri, Ali; Amini, Jalal; Dehmollaian, Mojtaba; Kavoosi, Mohammad Ali

    2017-05-01

    Determining surface morphology using synthetic aperture radar (SAR) data requires accurate topographic and microtopographic models. To distinguish different surface geometric patterns and to differentiate the formation of geological rock surfaces, it is necessary to model the smoothness and roughness of surfaces based on radar signal backscattering. Euclidean geometry is less able than fractal geometry to describe natural phenomena; however, in application to radar backscattering models, fractal geometry has never fully replaced Euclidean geometry. Using fractal geometry only, this paper attempts to improve the backscattering simulation generated by an Integral Equation Model to improve the description of geological rock surfaces. As the application of radar signal backscattering is a rarity in the domain of geology, the paper also discusses the efficiency of the method in improving the results of conventional geological mapping methods. The proposed method is applied to the Anaran geological formation (between Dehloran and Ilam in IRAN) using TerraSAR-X SAR data and in situ roughness measurements on pure sites with rough, intermediate, and smooth morphologies. This implementation shows fractal and diffractal behavior of geological morphologies under various conditions.

  17. Measurements of the vertical profile of water vapor abundance in the Martian atmosphere from Mars Observer

    Science.gov (United States)

    Schofield, J. T.; Mccleese, Daniel J.

    1988-01-01

    An analysis is presented of the Pressure Modulator Infrared Radiometer (PMIRR) capabilities along with how the vertical profiles of water vapor will be obtained. The PMIRR will employ filter and pressure modulation radiometry using nine spectral channels, in both limb scanning and nadir sounding modes, to obtain daily, global maps of temperature, dust extinction, condensate extinction, and water vapor mixing ratio profiles as a function of pressure to half scale height or 5 km vertical resolution. Surface thermal properties will also be mapped, and the polar radiactive balance will be monitored.

  18. Quantitative evaluation of sputtering induced surface roughness and its influence on AES depth profiles of polycrystalline Ni/Cu multilayer thin films

    Energy Technology Data Exchange (ETDEWEB)

    Yan, X.L.; Coetsee, E. [Department of Physics, University of the Free State, P O Box 339, Bloemfontein, ZA9300 (South Africa); Wang, J.Y., E-mail: wangjy@stu.edu.cn [Department of Physics, Shantou University, 243 Daxue Road, Shantou, 515063, Guangdong (China); Swart, H.C., E-mail: swartHC@ufs.ac.za [Department of Physics, University of the Free State, P O Box 339, Bloemfontein, ZA9300 (South Africa); Terblans, J.J., E-mail: terblansjj@ufs.ac.za [Department of Physics, University of the Free State, P O Box 339, Bloemfontein, ZA9300 (South Africa)

    2017-07-31

    Highlights: • Linear Least Square (LLS) method used to separate Ni and Cu Auger spectra. • The depth-dependent ion sputtering induced roughness was quantitatively evaluated. • The depth resolution better when profiling with dual-ion beam vs. a single-ion beam. • AES depth profiling with a lower ion energy results in a better depth resolution. - Abstract: The polycrystalline Ni/Cu multilayer thin films consisting of 8 alternating layers of Ni and Cu were deposited on a SiO{sub 2} substrate by means of electron beam evaporation in a high vacuum. Concentration-depth profiles of the as-deposited multilayered Ni/Cu thin films were determined with Auger electron spectroscopy (AES) in combination with Ar{sup +} ion sputtering, under various bombardment conditions with the samples been stationary as well as rotating in some cases. The Mixing-Roughness-Information depth (MRI) model used for the fittings of the concentration-depth profiles accounts for the interface broadening of the experimental depth profiling. The interface broadening incorporates the effects of atomic mixing, surface roughness and information depth of the Auger electrons. The roughness values extracted from the MRI model fitting of the depth profiling data agrees well with those measured by atomic force microscopy (AFM). The ion sputtering induced surface roughness during the depth profiling was accordingly quantitatively evaluated from the fitted MRI parameters with sample rotation and stationary conditions. The depth resolutions of the AES depth profiles were derived directly from the values determined by the fitting parameters in the MRI model.

  19. Effect of surface fissure on apparent resistivity measurements

    Science.gov (United States)

    Sailhac, P.; Gance, J.; Malet, J.

    2013-12-01

    Fissures are features of interest, prone to create preferential flow path, modifying locally the soil hydrogeological behavior. Electrical Resistivity Tomography (ERT) is a suitable tool to monitor such preferential flow path. However, this technique is not efficient in the presence of surface fissure, due to a bad resistivity recovering around the fissure vicinity during the inversion process. Therefore, we propose a description of fissure effect on raw apparent resistivity on three resistivity arrays. The purposes of the study are multiple. First, we aim at making ERT users aware of surface fissure effect, and propose a first help to interpret basically resistivity pseudo sections. Second, we propose to ERT users to automatically conduct a surface fissure survey on the studied profile, in order to consider each fissure in a forward DC model and to suppress their effect. Finally, this study is only a first step toward 2D fissure shape inversion, and time-lapse monitoring of fissure drying and filling. In this study, we create a fissure model based on different geomorphological descriptors. After describing the FEM-DC forward modeling strategy, we investigate the fissure effect on pseudo section of apparent resistivity for a Wenner-Schlumberger (WS), a dipole-dipole (DD) and a gradient (GRAD) array. We determine a fissure detectability threshold for each array and perform a sensitivity analysis on the different fissure parameters (position, width, depth, dip angles...). The crack filling or drying effect is also investigated. The possibility to remove fissure effect and to propose a first interpretation of time-lapse data is illustrated on real data. This study show again the higher sensitivity of the DD array compared to the GRAD and WS arrays. Not only the maximal amplitude in the pseudo section is higher for the DD array, but also the anomaly pattern created by the fissure is much larger for this acquisition geometry. The minimal depth detectable for the DD

  20. Reliability of surface EMG measurements from the suprahyoid muscle complex

    DEFF Research Database (Denmark)

    Kothari, Mohit; Stubbs, Peter William; Pedersen, Asger Roer

    2017-01-01

    of using the suprahyoid muscle complex (SMC) using surface electromyography (sEMG) to assess changes to neural pathways by determining the reliability of measurements in healthy participants over days. Methods: Seventeen healthy participants were recruited. Measurements were performed twice with one week...... between sessions. Single pulse (at 120% and 140% of the resting motor threshold (rMT)) and paired pulse (2 ms and 15 ms paired pulse) transcranial magnetic stimulation (TMS) were used to elicit MEPs in the SMC which were recorded using sEMG. Results: ≈50% of participants (range: 42%-58%; depending...... on stimulus type/intensity) had significantly different MEP values between day 1 and day 2 for single pulse and paired pulse TMS. A large stimulus artefact resulted in MEP responses that could not be assessed in four participants. Conclusions: The assessment of the SMC using sEMG following TMS was poorly...

  1. Measurement of Tritium Surface Distribution on TFTR Bumper Limiter Tiles

    International Nuclear Information System (INIS)

    Sugiyama, K.; Tanabe, T.; Skinner, C.H.; Gentile, C.A.

    2004-01-01

    The tritium surface distribution on graphite tiles used in the Tokamak Fusion Test Reactor (TFTR) bumper limiter and exposed to TFTR deuterium-tritium (D-T) discharges from 1993 to 1997 was measured by the Tritium Imaging Plate Technique (TIPT). The TFTR bumper limiter shows both re-/co-deposition and erosion. The tritium images for all tiles measured are strongly correlated with erosion and deposition patterns, and long-term tritium retention was found in the re-/co-depositions and flakes. The CFC tiles located at erosion dominated areas clearly showed their woven structure in their tritium images owing to different erosion yields between fibers and matrix. Significantly high tritium retention was observed on all sides of the erosion tiles, indicating carbon transport via repetition of local erosion/deposition cycles

  2. 3D Surface Temperature Measurement of Plant Canopies Using Photogrammetry Techniques From A UAV.

    Science.gov (United States)

    Irvine, M.; Lagouarde, J. P.

    2017-12-01

    Surface temperature of plant canopies and within canopies results from the coupling of radiative and energy exchanges processes which govern the fluxes at the interface soil-plant-atmosphere. As a key parameter, surface temperature permits the estimation of canopy exchanges using processes based modeling methods. However detailed 3D surface temperature measurements or even profile surface temperature measurements are rarely made as they have inherent difficulties. Such measurements would greatly improve multi-level canopy models such as NOAH (Chen and Dudhia 2001) or MuSICA (Ogée and Brunet 2002, Ogée et al 2003) where key surface temperature estimations, at present, are not tested. Additionally, at larger scales, canopy structure greatly influences satellite based surface temperature measurements as the structure impacts the observations which are intrinsically made at varying satellite viewing angles and solar heights. In order to account for these differences, again accurate modeling is required such as through the above mentioned multi-layer models or with several source type models such as SCOPE (Van der Tol 2009) in order to standardize observations. As before, in order to validate these models, detailed field observations are required. With the need for detailed surface temperature observations in mind we have planned a series of experiments over non-dense plant canopies to investigate the use of photogrammetry techniques. Photogrammetry is normally used for visible wavelengths to produce 3D images using cloud point reconstruction of aerial images (for example Dandois and Ellis, 2010, 2013 over a forest). From these cloud point models it should be possible to establish 3D plant surface temperature images when using thermal infrared array sensors. In order to do this our experiments are based on the use of a thermal Infrared camera embarked on a UAV. We adapt standard photogrammetry to account for limits imposed by thermal imaginary, especially the low

  3. Analysis of Mass Profiles and Cooling Flows of Bright, Early-Type Galaxies AO2, AO3 and Surface Brightness Profiles and Energetics of Intracluster Gas in Cool Galaxy Clusters AO3

    Science.gov (United States)

    White, Raymond E., III

    1998-01-01

    This final report uses ROSAT observations to analyze two different studies. These studies are: Analysis of Mass Profiles and Cooling Flows of Bright, Early-Type Galaxies; and Surface Brightness Profiles and Energetics of Intracluster Gas in Cool Galaxy Clusters.

  4. Measured ground-surface movements, Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Massey, B.L.

    1981-01-01

    The Cerro Prieto geothermal area in the Mexicali Valley, 30 kilometers southeast of Mexicali, Baja California, incurred slight deformation because of the extraction of hot water and steam, and probably, active tectonism. During 1977 to 1978, the US Geological Survey established and measured two networks of horizontal control in an effort to define both types of movement. These networks consisted of: (1) a regional trilateration net brought into the mountain ranges west of the geothermal area from stations on an existing US Geological Survey crustal-strain network north of the international border; and (2) a local net tied to stations in the regional net and encompassing the present and planned geothermal production area. Electronic distance measuring instruments were used to measure the distances between stations in both networks in 1978, 1979 and 1981. Lines in the regional net averaged 25 km. in length and the standard deviation of an individual measurement is estimated to be approx. 0.3 part per million of line length. The local network was measured using different instrumentation and techniques. The average line length was about 5 km. and the standard deviation of an individual measurement approached 3 parts per million per line length. Ground-surface movements in the regional net, as measured by both the 1979 and 1981 resurveys, were small and did not exceed the noise level. The 1979 resurvey of the local net showed an apparent movement of 2 to 3 centimeters inward toward the center of the production area. This apparent movement was restricted to the general limits of the production area. The 1981 resurvey of the local net did not show increased movement attributable to fluid extraction.

  5. Detection of flaws on surface of civil infrastructures and their profiling using imaging system with laser displacement sensor

    Science.gov (United States)

    Giri, Paritosh; Kharkovsky, Sergey

    2016-04-01

    Civil infrastructures such as buildings, bridges, roads and pipelines are the integral part of people's lives and their failure can have large public safety and economic consequences. Early detection of flaws in civil infrastructures and their appropriate retrofitting will aid in preventing this failure. Flaws such as cracks and impact damages initially occur on the surface and propagate inside the materials causing further degradation. There is a need to develop systems that can detect these surface flaws. Developing a system with one sensing technique which can detect the flaws is a challenging task since infrastructures are made up of diverse materials such as concrete, metal, plastics, composite and timber that have different electrical and mechanical properties. It is also desired that non-plain surfaces with complex profiles can be interrogated and surface flaws can be detected. We have proposed an imaging system capable of interrogating structures with complex surface profiles for the purpose of detection and evaluation of surface flaws such as cracks and impact damages using laser displacement sensor (LDS). The developed system consists of LDS mounted on the scanner which is able to perform raster scan over the specimen under test. The reading of displacement from the sensor head to the laser spot on the surface of the test material is then used to generate images which can be used to detect the surface flaws. The proof of concept is given by testing specimens made of metal, concrete and plastics with complex surface profiles.

  6. Calculation of the Scattered Radiation Profile in 64 Slice CT Scanners Using Experimental Measurement

    Directory of Open Access Journals (Sweden)

    Afshin Akbarzadeh

    2009-06-01

    Full Text Available Introduction: One of the most important parameters in x-ray CT imaging is the noise induced by detected scattered radiation. The detected scattered radiation is completely dependent on the scanner geometry as well as size, shape and material of the scanned object. The magnitude and spatial distribution of the scattered radiation in x-ray CT should be quantified for development of robust scatter correction techniques. Empirical methods based on blocking the primary photons in a small region are not able to extract scatter in all elements of the detector array while the scatter profile is required for a scatter correction procedure. In this study, we measured scatter profiles in 64 slice CT scanners using a new experimental measurement. Material and Methods: To measure the scatter profile, a lead block array was inserted under the collimator and the phantom was exposed at the isocenter. The raw data file, which contained detector array readouts, was transferred to a PC and was read using a dedicated GUI running under MatLab 7.5. The scatter profile was extracted by interpolating the shadowed area. Results: The scatter and SPR profiles were measured. Increasing the tube voltage from 80 to 140 kVp resulted in an 80% fall off in SPR for a water phantom (d=210 mm and 86% for a polypropylene phantom (d = 350 mm. Increasing the air gap to 20.9 cm caused a 30% decrease in SPR. Conclusion: In this study, we presented a novel approach for measurement of scattered radiation distribution and SPR in a CT scanner with 64-slice capability using a lead block array. The method can also be used on other multi-slice CT scanners. The proposed technique can accurately estimate scatter profiles. It is relatively straightforward, easy to use, and can be used for any related measurement.

  7. Measurements of land surface features using an airborne laser altimeter: the HAPEX-Sahel experiment

    International Nuclear Information System (INIS)

    Ritchie, J.C.; Menenti, M.; Weltz, M.A.

    1997-01-01

    An airborne laser profiling altimeter was used to measure surface features and properties of the landscape during the HAPEX-Sahel Experiment in Niger, Africa in September 1992. The laser altimeter makes 4000 measurements per second with a vertical resolution of 5 cm. Airborne laser and detailed field measurements of vegetation heights had similar average heights and frequency distribution. Laser transects were used to estimate land surface topography, gully and channel morphology, and vegetation properties ( height, cover and distribution). Land surface changes related to soil erosion and channel development were measured. For 1 km laser transects over tiger bush communities, the maximum vegetation height was between 4-5 and 6-5 m, with an average height of 21 m. Distances between the centre of rows of tiger bush vegetation averaged 100 m. For two laser transects, ground cover for tiger bush was estimated to be 225 and 301 per cent for vegetation greater than 0-5m tall and 190 and 25-8 per cent for vegetation greater than 10m tall. These values are similar to published values for tiger bush. Vegetation cover for 14 and 18 km transects was estimated to be 4 per cent for vegetation greater than 0-5 m tall. These cover values agree within 1-2 per cent with published data for short transects (⩾ 100 m) for the area. The laser altimeter provided quick and accurate measurements for evaluating changes in land surface features. Such information provides a basis for understanding land degradation and a basis for management plans to rehabilitate the landscape. (author)

  8. Measuring surface energy and evapotranspiration across Caribbean mangrove forests

    Science.gov (United States)

    Lagomasino, D.; Fatoyinbo, T. E.; Price, R.

    2014-12-01

    Coastal mangroves lose large amounts of water through evapotranspiration (ET) that can be equivalent to the amount of annual rainfall in certain years. Satellite remote sensing has been used to estimate surface energy and ET variability in many forested ecosystems, yet has been widely overlooked in mangrove forests. Using a combination of long-term datasets (30-year) acquired from the NASA Landsat 5 and 7 satellite databases, the present study investigated ET and surface energy balance variability between two mangrove forest sites in the Caribbean: 1) Everglades National Park (ENP; Florida, USA) and 2) Sian Ka'an Biosphere Reserve (SKBR; Quintana Roo, Mexico). A satellite-derived surface energy balance model was used to estimate ET in tall and scrub mangroves environments at ENP and SKBR. Results identified significant differences in soil heat flux measurements and ET between the tall and scrub mangrove environments. Scrub mangroves exhibited the highest soil heat flux coincident with the lowest biophysical indices (i.e., Fractional Vegetation Cover, Normalized Difference Vegetation Index, and Soil-Adjusted Vegetation Index) and ET rates. Mangrove damage and mortality was observed on the satellite images following strong tropical storms and associated with anthropogenic modifications and resulted in low values in spectral vegetation indices, higher soil heat flux, and higher ET. Recovery of the spectral characteristics, soil heat flux and ET was within 1-2 years following hurricane disturbance while, degradation caused by human disturbance persisted for many years. Remotely sensed ET of mangrove forests can provide estimates over a few decades and provide us with some understanding of how these environments respond to disturbances to the landscape in periods where no ground data exists or in locations that are difficult to access. Moreover, relationships between energy and water balance components developed for the coastal mangroves of Florida and Mexico could be

  9. Profile measurements in the plasma edge of mega amp spherical tokamak using a ball pen probe.

    Science.gov (United States)

    Walkden, N R; Adamek, J; Allan, S; Dudson, B D; Elmore, S; Fishpool, G; Harrison, J; Kirk, A; Komm, M

    2015-02-01

    The ball pen probe (BPP) technique is used successfully to make profile measurements of plasma potential, electron temperature, and radial electric field on the Mega Amp Spherical Tokamak. The potential profile measured by the BPP is shown to significantly differ from the floating potential both in polarity and profile shape. By combining the BPP potential and the floating potential, the electron temperature can be measured, which is compared with the Thomson scattering (TS) diagnostic. Excellent agreement between the two diagnostics is obtained when secondary electron emission is accounted for in the floating potential. From the BPP profile, an estimate of the radial electric field is extracted which is shown to be of the order ∼1 kV/m and increases with plasma current. Corrections to the BPP measurement, constrained by the TS comparison, introduce uncertainty into the ER measurements. The uncertainty is most significant in the electric field well inside the separatrix. The electric field is used to estimate toroidal and poloidal rotation velocities from E × B motion. This paper further demonstrates the ability of the ball pen probe to make valuable and important measurements in the boundary plasma of a tokamak.

  10. Profile measurements in the plasma edge of mega amp spherical tokamak using a ball pen probe

    Science.gov (United States)

    Walkden, N. R.; Adamek, J.; Allan, S.; Dudson, B. D.; Elmore, S.; Fishpool, G.; Harrison, J.; Kirk, A.; Komm, M.

    2015-02-01

    The ball pen probe (BPP) technique is used successfully to make profile measurements of plasma potential, electron temperature, and radial electric field on the Mega Amp Spherical Tokamak. The potential profile measured by the BPP is shown to significantly differ from the floating potential both in polarity and profile shape. By combining the BPP potential and the floating potential, the electron temperature can be measured, which is compared with the Thomson scattering (TS) diagnostic. Excellent agreement between the two diagnostics is obtained when secondary electron emission is accounted for in the floating potential. From the BPP profile, an estimate of the radial electric field is extracted which is shown to be of the order ˜1 kV/m and increases with plasma current. Corrections to the BPP measurement, constrained by the TS comparison, introduce uncertainty into the ER measurements. The uncertainty is most significant in the electric field well inside the separatrix. The electric field is used to estimate toroidal and poloidal rotation velocities from E × B motion. This paper further demonstrates the ability of the ball pen probe to make valuable and important measurements in the boundary plasma of a tokamak.

  11. Profile measurements in the plasma edge of mega amp spherical tokamak using a ball pen probe

    International Nuclear Information System (INIS)

    Walkden, N. R.; Adamek, J.; Komm, M.; Allan, S.; Elmore, S.; Fishpool, G.; Harrison, J.; Kirk, A.; Dudson, B. D.

    2015-01-01

    The ball pen probe (BPP) technique is used successfully to make profile measurements of plasma potential, electron temperature, and radial electric field on the Mega Amp Spherical Tokamak. The potential profile measured by the BPP is shown to significantly differ from the floating potential both in polarity and profile shape. By combining the BPP potential and the floating potential, the electron temperature can be measured, which is compared with the Thomson scattering (TS) diagnostic. Excellent agreement between the two diagnostics is obtained when secondary electron emission is accounted for in the floating potential. From the BPP profile, an estimate of the radial electric field is extracted which is shown to be of the order ∼1 kV/m and increases with plasma current. Corrections to the BPP measurement, constrained by the TS comparison, introduce uncertainty into the E R measurements. The uncertainty is most significant in the electric field well inside the separatrix. The electric field is used to estimate toroidal and poloidal rotation velocities from E × B motion. This paper further demonstrates the ability of the ball pen probe to make valuable and important measurements in the boundary plasma of a tokamak

  12. Beam Profile Measurement in MTA Beam Line for High Pressure RF Cavity Beam Test

    International Nuclear Information System (INIS)

    Jana, M.R.; Bross, A.; Chung, M.; Greer, S.; Johnstone, C.; Kobilarcik, T.; Koizumi, G.; Leonova, M.; Moretti, A.; Popovic, M.; Schwartz, T.

    2012-01-01

    Recent High Pressure RF (HPRF) cavity experiment at MuCool Test Area (MTA) has used 400 MeV Linac proton beam to study the beam loading effect. When the energetic proton beam passes through the cavity, it ionizes the inside gas and produces the electrons. These electrons consume RF power inside the cavity. Number of electrons produced per cm inside the cavity (at 950 psi Hydrogen gas) per incident proton is ∼ 1200. The measurement of beam position and profile are necessary. MTA is flammable gas (Hydrogen) hazard zone so we have developed a passive beam diagnostic instrument using Chromox-6 scintillation screen and CCD camera. This paper presents quantitative information about beam position and beam profile. Neutral density filter was used to avoid saturation of CCD camera. Image data is filtered and fitted with Gaussian function to compute the beam size. The beam profile obtained from scintillation screen shall be compared with multi-wire beam profile.

  13. Measurement and modeling of nitrogen resonance line profiles from an electrodeless discharge lamp

    International Nuclear Information System (INIS)

    Wood, D.R.; Skinner, G.B.; Lifshitz, A.

    1987-01-01

    Experimental profiles of the 1200 A resonance triplet of atomic nitrogen were measured for a variety of operating conditions of an end-on electrodeless lamp, and corresponding absorption curves were calculated. Each source profile was determined by fitting parameters to an empirical two-layer model, then convoluting with the instrumental function for comparison with experimental data. Each three-component profile was fitted with three adjustable parameters: an absorption parameter for each of the two layers and a third absorption parameter to adjust for radiation trapping. Curves of absorption as a function of atom concentration, calculated from these profiles, are very similar to the shock tube calibrations of Thielen and Roth in which a source of similar design has been used

  14. From the chlorophyll a in the surface layer to its vertical profile: a Greenland Sea relationship for satellite applications

    Directory of Open Access Journals (Sweden)

    A. Cherkasheva

    2013-04-01

    Full Text Available Current estimates of global marine primary production range over a factor of two. Improving these estimates requires an accurate knowledge of the chlorophyll vertical profiles, since they are the basis for most primary production models. At high latitudes, the uncertainty in primary production estimates is larger than globally, because here phytoplankton absorption shows specific characteristics due to the low-light adaptation, and in situ data and ocean colour observations are scarce. To date, studies describing the typical chlorophyll profile based on the chlorophyll in the surface layer have not included the Arctic region, or, if it was included, the dependence of the profile shape on surface concentration was neglected. The goal of our study was to derive and describe the typical Greenland Sea chlorophyll profiles, categorized according to the chlorophyll concentration in the surface layer and further monthly resolved profiles. The Greenland Sea was chosen because it is known to be one of the most productive regions of the Arctic and is among the regions in the Arctic where most chlorophyll field data are available. Our database contained 1199 chlorophyll profiles from R/Vs Polarstern and Maria S. Merian cruises combined with data from the ARCSS-PP database (Arctic primary production in situ database for the years 1957–2010. The profiles were categorized according to their mean concentration in the surface layer, and then monthly median profiles within each category were calculated. The category with the surface layer chlorophyll (CHL exceeding 0.7 mg C m−3 showed values gradually decreasing from April to August. A similar seasonal pattern was observed when monthly profiles were averaged over all the surface CHL concentrations. The maxima of all chlorophyll profiles moved from the greater depths to the surface from spring to late summer respectively. The profiles with the smallest surface values always showed a subsurface chlorophyll

  15. Neural networks for the dimensionality reduction of GOME measurement vector in the estimation of ozone profiles

    International Nuclear Information System (INIS)

    Del Frate, F.; Iapaolo, M.; Casadio, S.; Godin-Beekmann, S.; Petitdidier, M.

    2005-01-01

    Dimensionality reduction can be of crucial importance in the application of inversion schemes to atmospheric remote sensing data. In this study the problem of dimensionality reduction in the retrieval of ozone concentration profiles from the radiance measurements provided by the instrument Global Ozone Monitoring Experiment (GOME) on board of ESA satellite ERS-2 is considered. By means of radiative transfer modelling, neural networks and pruning algorithms, a complete procedure has been designed to extract the GOME spectral ranges most crucial for the inversion. The quality of the resulting retrieval algorithm has been evaluated by comparing its performance to that yielded by other schemes and co-located profiles obtained with lidar measurements

  16. Neural networks for the dimensionality reduction of GOME measurement vector in the estimation of ozone profiles

    Energy Technology Data Exchange (ETDEWEB)

    Del Frate, F. [Dipartimento di Informatica Sistemi e Produzione, Universita Tor Vergata, Viadel Politecnico 1, I-00133 Rome (Italy)]. E-mail: delfrate@disp.uniroma2.it; Iapaolo, M. [Dipartimento di Informatica Sistemi e Produzione, Universita Tor Vergata, Viadel Politecnico 1, I-00133 Rome (Italy); Casadio, S. [Institut for Geophysics, Karl Franzens University of Graz, c/o ESA/ESRIN, Via G. Galilei, I-00044 Rome (Italy); Godin-Beekmann, S. [Institut Pierre Simon Laplace, Service d' Aeronomie, UPMC - Boite 102, 4 Place Jussieu, 75252 Paris Cedex 05 (France); Petitdidier, M. [Institut Pierre Simon Laplace, Centre d' etude des Environnements Terrestre et Planetaires, 10-12 Avenue de l' Europe, 78140 Velizy (France)

    2005-05-15

    Dimensionality reduction can be of crucial importance in the application of inversion schemes to atmospheric remote sensing data. In this study the problem of dimensionality reduction in the retrieval of ozone concentration profiles from the radiance measurements provided by the instrument Global Ozone Monitoring Experiment (GOME) on board of ESA satellite ERS-2 is considered. By means of radiative transfer modelling, neural networks and pruning algorithms, a complete procedure has been designed to extract the GOME spectral ranges most crucial for the inversion. The quality of the resulting retrieval algorithm has been evaluated by comparing its performance to that yielded by other schemes and co-located profiles obtained with lidar measurements.

  17. Neural networks for the dimensionality reduction of GOME measurement vector in the estimation of ozone profiles

    Science.gov (United States)

    Del Frate, F.; Iapaolo, M.; Casadio, S.; Godin-Beekmann, S.; Petitdidier, M.

    2005-05-01

    Dimensionality reduction can be of crucial importance in the application of inversion schemes to atmospheric remote sensing data. In this study the problem of dimensionality reduction in the retrieval of ozone concentration profiles from the radiance measurements provided by the instrument Global Ozone Monitoring Experiment (GOME) on board of ESA satellite ERS-2 is considered. By means of radiative transfer modelling, neural networks and pruning algorithms, a complete procedure has been designed to extract the GOME spectral ranges most crucial for the inversion. The quality of the resulting retrieval algorithm has been evaluated by comparing its performance to that yielded by other schemes and co-located profiles obtained with lidar measurements.

  18. Entrance surface dose measurements in mammography using thermoluminescence technique

    International Nuclear Information System (INIS)

    Rivera, T.; Vega C, H.R.; Manzanares A, E; Azorin, J.; Gonzalez, P.R.

    2007-01-01

    Full text: Of the various techniques that can be used for personnel dosimetry, thermoluminescence dosimetry (TLD) has emerged as a superior technique due to its manifold advantages over other methods of dose estimation. Various phosphors have been therefore investigated regarding their suitability for dosimetry. In this paper, a dosimetry system based on thermally stimulated luminescence (TSL) from zirconium oxide phosphors embedded in polytetrafluorethylene (ZrO 2 +PTFE) was developed for entrance surface doses (ES) measurements in mammography. Small ZrO 2 pellets of 5 mm in diameter and 0.8 mm in thickness were used. The reproducibility of measurements and linearity of ZrO 2 were also studied. The results were compared with those obtained from LiF:Mg,Cu,P usually used for the determination of absorbed dose in mammography. Measurements both per unit air kerma and In vivo were performed using a mammography unit model DMR (General Electric). The results showed that ZrO 2 TLDs can be used for the same X-ray dosimetry applications as LiF:Mg,Cu,P, with each type having the disadvantage of a response dependent on energy, particularly at low energies. These results indicate a considerable potential for use in routine control and In vivo ES measurements in mammography. (Author)

  19. Optical bi-sensorial measurement system for production control of extruded profiles

    Science.gov (United States)

    Weckenmann, A.; Bernstein, J.

    2008-09-01

    Extruded profiles are semi-finished products (made out of steel, brass, aluminum, synthetics...) which are appointed for wide applications in manufacturing of technical products. As yet used optical sensors in process control working to the shading technology detect the object's shadow orthographically to the axis of illumination. As a consequence they record it unattached by the profiles coat in measurement range at any point of the measured profile with high precision. As a matter of fact, concave zones cannot be captured. Alternatively the measurement of concave zones can be arranged by light-section systems. These do not comply with the required accuracy, are comparatively slow and moreover affected by dislocations of the section of the profile. A measurement system including a light-section and a shading system combines the advantages of both optical systems. It is to serve with a reliable conception for the assembly of a bi-sensorial measurement system consisting of both systems as well as suitable methods of analysis for the in-line inspection of concave profiles. As a result it contains conclusions concerning requirements of the light source, the arrangement of this source and the cameras, obtainable precision and sampling rate as well as the essential synchronization of both systems. After designing an appropriate prototype, the selected light-section system and the shading system will be synchronized and aligned. Therefore, the metered geometrical data will be merged for the evaluation of form deviation. So, developed and adapted software supports and contains proposals to the uncertainty after successful tests. The system and a calibration method will be proved in production where robustness will be a most critical despite of heat, dust and vibrations. The target uncertainty of less than 0.1 mm at every section of the profiles coat has to be met.

  20. Ozone profile smoothness as a priori information in the inversion of limb measurements

    Directory of Open Access Journals (Sweden)

    V. F. Sofieva

    2004-11-01

    Full Text Available In this work we discuss inclusion of a priori information about the smoothness of atmospheric profiles in inversion algorithms. The smoothness requirement can be formulated in the form of Tikhonov-type regularization, where the smoothness of atmospheric profiles is considered as a constraint or in the form of Bayesian optimal estimation (maximum a posteriori method, MAP, where the smoothness of profiles can be included as a priori information. We develop further two recently proposed retrieval methods. One of them - Tikhonov-type regularization according to the target resolution - develops the classical Tikhonov regularization. The second method - maximum a posteriori method with smoothness a priori - effectively combines the ideas of the classical MAP method and Tikhonov-type regularization. We discuss a grid-independent formulation for the proposed inversion methods, thus isolating the choice of calculation grid from the question of how strong the smoothing should be. The discussed approaches are applied to the problem of ozone profile retrieval from stellar occultation measurements by the GOMOS instrument on board the Envisat satellite. Realistic simulations for the typical measurement conditions with smoothness a priori information created from 10-years analysis of ozone sounding at Sodankylä and analysis of the total retrieval error illustrate the advantages of the proposed methods. The proposed methods are equally applicable to other profile retrieval problems from remote sensing measurements.

  1. Ozone profile smoothness as a priori information in the inversion of limb measurements

    Directory of Open Access Journals (Sweden)

    V. F. Sofieva

    2004-11-01

    Full Text Available In this work we discuss inclusion of a priori information about the smoothness of atmospheric profiles in inversion algorithms. The smoothness requirement can be formulated in the form of Tikhonov-type regularization, where the smoothness of atmospheric profiles is considered as a constraint or in the form of Bayesian optimal estimation (maximum a posteriori method, MAP, where the smoothness of profiles can be included as a priori information. We develop further two recently proposed retrieval methods. One of them - Tikhonov-type regularization according to the target resolution - develops the classical Tikhonov regularization. The second method - maximum a posteriori method with smoothness a priori - effectively combines the ideas of the classical MAP method and Tikhonov-type regularization. We discuss a grid-independent formulation for the proposed inversion methods, thus isolating the choice of calculation grid from the question of how strong the smoothing should be.

    The discussed approaches are applied to the problem of ozone profile retrieval from stellar occultation measurements by the GOMOS instrument on board the Envisat satellite. Realistic simulations for the typical measurement conditions with smoothness a priori information created from 10-years analysis of ozone sounding at Sodankylä and analysis of the total retrieval error illustrate the advantages of the proposed methods.

    The proposed methods are equally applicable to other profile retrieval problems from remote sensing measurements.

  2. Accurate fluid force measurement based on control surface integration

    Science.gov (United States)

    Lentink, David

    2018-01-01

    Nonintrusive 3D fluid force measurements are still challenging to conduct accurately for freely moving animals, vehicles, and deforming objects. Two techniques, 3D particle image velocimetry (PIV) and a new technique, the aerodynamic force platform (AFP), address this. Both rely on the control volume integral for momentum; whereas PIV requires numerical integration of flow fields, the AFP performs the integration mechanically based on rigid walls that form the control surface. The accuracy of both PIV and AFP measurements based on the control surface integration is thought to hinge on determining the unsteady body force associated with the acceleration of the volume of displaced fluid. Here, I introduce a set of non-dimensional error ratios to show which fluid and body parameters make the error negligible. The unsteady body force is insignificant in all conditions where the average density of the body is much greater than the density of the fluid, e.g., in gas. Whenever a strongly deforming body experiences significant buoyancy and acceleration, the error is significant. Remarkably, this error can be entirely corrected for with an exact factor provided that the body has a sufficiently homogenous density or acceleration distribution, which is common in liquids. The correction factor for omitting the unsteady body force, {{{ {ρ f}} {1 - {ρ f} ( {{ρ b}+{ρ f}} )}.{( {{{{ρ }}b}+{ρ f}} )}}} , depends only on the fluid, {ρ f}, and body, {{ρ }}b, density. Whereas these straightforward solutions work even at the liquid-gas interface in a significant number of cases, they do not work for generalized bodies undergoing buoyancy in combination with appreciable body density inhomogeneity, volume change (PIV), or volume rate-of-change (PIV and AFP). In these less common cases, the 3D body shape needs to be measured and resolved in time and space to estimate the unsteady body force. The analysis shows that accounting for the unsteady body force is straightforward to non

  3. Adaptation profiles comprising objective and subjective measures in fibromyalgia: the al-Ándalus project.

    Science.gov (United States)

    Estévez-López, Fernando; Segura-Jiménez, Víctor; Álvarez-Gallardo, Inmaculada C; Borges-Cosic, Milkana; Pulido-Martos, Manuel; Carbonell-Baeza, Ana; Aparicio, Virginia A; Geenen, Rinie; Delgado-Fernández, Manuel

    2017-11-01

    The aim of this study was to identify subgroups in terms of adaptation to FM and to test differences in FM severity between these subgroups. The al-Ándalus project made it possible to perform a comprehensive population-based cross-sectional study in 486 FM patients including multiple assessments of modifiable (could be targeted in therapy) resilience and vulnerability factors, measured by objective and subjective assessments, related to psychological and physical function. FM severity was assessed by means of FM impact (total score of the Revised Fibromyalgia Impact Questionnaire) and distress (Polysymptomatic Distress Scale of the modified 2011 preliminary criteria for FM). Exploratory factor analysis, cluster analysis and analysis of variance were conducted. Factor analysis yielded eight factors: three included objective measures (declarative memory, active lifestyle and objective physical fitness) and five included subjective measures (fatigue, psychological distress, catastrophizing, resilience and subjective physical fitness). Cluster analysis based on these eight factors identified five profiles: Adapted (16%), Fit (18%), Poor performer (20%), Positive (20%) and Maladapted (26%). Most profile comparisons revealed different levels of FM severity varying from Adapted (the most favourable profile) to Maladapted (the most unfavourable profile) with Fit, Poor performer and Positive obtaining intermediate positions. Heterogeneity of FM was shown by five clinically meaningful profiles of modifiable factors that were associated with FM severity. It is of clinical interest to examine whether these profiles are associated with FM prognosis and the effectiveness of interventions, which would enhance the development of customized interventions based on adaptation profiles in FM. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  4. A robust fibre laser system for electro-optic electron bunch profile measurements at FLASH

    International Nuclear Information System (INIS)

    Wissmann, Laurens-Georg

    2012-08-01

    For the electro-optic measurement of electron bunch profiles at FLASH a robust ytterbium doped fibre laser (YDFL) system has been developed consisting of a laser oscillator and a two-staged amplifier. The oscillator is designed to meet the specifications of high reliability and low noise operation. The amplifier makes use of tailored nonlinearity to enhance the spectral bandwidth of the output laser pulses. Active repetition rate control enables sub-picosecond synchronisation of the laser to the accelerator reference RF. Using a two-stage gating scheme the output pulse train repetition rate is adopted to the accelerator repetition rate. An experimental site used for electro-optic electron bunch diagnostics has been redesigned to support single-shot bunch profile measurements based on spectral decoding. An existing bunch profile monitor with a similar laser system was upgraded and electro-optic bunch profile measurements were conducted, allowing for a comparison with measurements done with other longitudinal electron bunch diagnostics and with former measurements.

  5. A robust fibre laser system for electro-optic electron bunch profile measurements at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Wissmann, Laurens-Georg

    2012-08-15

    For the electro-optic measurement of electron bunch profiles at FLASH a robust ytterbium doped fibre laser (YDFL) system has been developed consisting of a laser oscillator and a two-staged amplifier. The oscillator is designed to meet the specifications of high reliability and low noise operation. The amplifier makes use of tailored nonlinearity to enhance the spectral bandwidth of the output laser pulses. Active repetition rate control enables sub-picosecond synchronisation of the laser to the accelerator reference RF. Using a two-stage gating scheme the output pulse train repetition rate is adopted to the accelerator repetition rate. An experimental site used for electro-optic electron bunch diagnostics has been redesigned to support single-shot bunch profile measurements based on spectral decoding. An existing bunch profile monitor with a similar laser system was upgraded and electro-optic bunch profile measurements were conducted, allowing for a comparison with measurements done with other longitudinal electron bunch diagnostics and with former measurements.

  6. Clear air boundary layer spaced antenna wind measurement with the Multiple Antenna Profiler (MAPR

    Directory of Open Access Journals (Sweden)

    S. A. Cohn

    Full Text Available Spaced antenna (SA wind measurement techniques are applied to Multiple Antenna Profiler (MAPR data to evaluate its performance in clear air conditions. MAPR is a multiple antenna 915 MHz wind profiler developed at the National Center for Atmospheric Research (NCAR and described in Cohn et al. (1997, designed to make high resolution wind measurements. Previous reported measurements with MAPR were restricted to precipitation because of low signal to noise (SNR and signal to ground-clutter (SCR ratios. By using a standard pulse-coding technique and upgrading the profiler control software, increases in average power and SNR were achieved, making routine measurements in clear air possible. Comparison of winds measured by MAPR and by a sonic anemometer on a nearby 300 m tower show correlation coefficients in the range of R2 = 0.75 – 0.80, and an average absolute error of ~ 1.4 m s - 1 . This compares favorably with the agreement typically found in wind profiler comparisons. We also consider the use of the parameter ah , which is related to the value of the cross-correlation function at its zero crossing. This parameter is a data quality indicator and possibly a key component in a ground clutter removal technique.

    Key words. Meteorology and atmospheric dynamics (mesoscale meteorology; instruments and techniques – Radio science (remote sensing

  7. A new temperature profiling probe for investigating groundwater-surface water interaction

    Science.gov (United States)

    Naranjo, Ramon C.; Robert Turcotte,

    2015-01-01

    Measuring vertically nested temperatures at the streambed interface poses practical challenges that are addressed here with a new discrete subsurface temperature profiling probe. We describe a new temperature probe and its application for heat as a tracer investigations to demonstrate the probe's utility. Accuracy and response time of temperature measurements made at 6 discrete depths in the probe were analyzed in the laboratory using temperature bath experiments. We find the temperature probe to be an accurate and robust instrument that allows for easily installation and long-term monitoring in highly variable environments. Because the probe is inexpensive and versatile, it is useful for many environmental applications that require temperature data collection for periods of several months in environments that are difficult to access or require minimal disturbance.

  8. Design of co-path scanning long trace profiler for measurement of x-ray space optical elements

    Science.gov (United States)

    Shun, Li; Yan, Gong; Wei, Zhang; Yang, Zhao

    2010-08-01

    The Long Trace Profiler (LTP) is a precision surface slope error measurement instrument used in synchrotron radiation optics for many years. By making some modifications to the LTP system, we developed a co-path scanning LTP (CSLTP) system to test the cylindrical aspherical surface which used in X-ray space optics. To reduce the mistake caused by air turbulence and manufacture faults of optical elements used, the CSLTP is designed with the least difference between the testing beam path and the reference beam path. Also, it uses multiple-beam interference but double beam interference to reduce the width of beam fringe. This improves the position precision of the beam fringe on the image plane.

  9. Toothbrush probe for instantaneous measurement of radial profile in tokamak boundary plasma

    Energy Technology Data Exchange (ETDEWEB)

    Uehara, Kazuya; Sengoku, Seio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Amemiya, Hiroshi

    1997-04-01

    A new probe for the instantaneous measurement of radial profiles of the boundary scrape-off layer (SOL) plasma has been developed in a tokamak. Five asymmetric double-probe chips are aligned in parallel to a strong magnetic field in the boundary plasma in a tokamak. This probe is named the `toothbrush probe` and can measure the ion temperature as well as the electron temperature and the plasma density in the SOL plasma within only one tokamak plasma shot. First, only one asymmetric probe is mounted on the divertor plate and it is tried to determine the ion temperature. Then, a manufactured toothbrush probe is mounted in the SOL plasma and the radial plasma profiles are simultaneously obtained. Data on the e-folding length of the plasma profile obtained by the toothbrush probe can determine the information on the transport properties such as the diffusion coefficient and the thermal conductivity of electrons and ions. (author)

  10. Modeling and Experimental Tests of a Mechatronic Device to Measure Road Profiles Considering Impact Dynamics

    DEFF Research Database (Denmark)

    Souza, A.; Santos, Ilmar

    2002-01-01

    of a vehicle and to test its components in laboratory. In this framework a mechanism to measure road profiles is designed and presented. Such a mechanism is composed of two rolling wheels and two long beams attached to the vehicles by means of four Kardan joints. The wheels are kept in contact to the ground...... to highlight that the aim of this device is to independently measure two road profiles, without the influence of the vehicle dynamics where the mechanism is attached. Before the mechatronic mechanism is attached to a real vehicle, its dynamic behavior must be known. A theoretical analysis of the mechanism...... predicts well the mechanism movements. However it was also experimentally observed that the contact between the wheels and the road profile is not permanent. To analyze the non-contact between the wheels and the road, the Newton-Euler´s Method is used to calculate forces and moments of reactions between...

  11. Response Surface Methods For Spatially-Resolved Optical Measurement Techniques

    Science.gov (United States)

    Danehy, P. M.; Dorrington, A. A.; Cutler, A. D.; DeLoach, R.

    2003-01-01

    Response surface methods (or methodology), RSM, have been applied to improve data quality for two vastly different spatially-resolved optical measurement techniques. In the first application, modern design of experiments (MDOE) methods, including RSM, are employed to map the temperature field in a direct-connect supersonic combustion test facility at NASA Langley Research Center. The laser-based measurement technique known as coherent anti-Stokes Raman spectroscopy (CARS) is used to measure temperature at various locations in the combustor. RSM is then used to develop temperature maps of the flow. Even though the temperature fluctuations at a single point in the flowfield have a standard deviation on the order of 300 K, RSM provides analytic fits to the data having 95% confidence interval half width uncertainties in the fit as low as +/- 30 K. Methods of optimizing future CARS experiments are explored. The second application of RSM is to quantify the shape of a 5-meter diameter, ultra-lightweight, inflatable space antenna at NASA Langley Research Center. Photogrammetry is used to simultaneously measure the shape of the antenna at approximately 500 discrete spatial locations. RSM allows an analytic model to be developed that describes the shape of the majority of the antenna with an uncertainty of 0.4 mm, with 95% confidence. This model would allow a quantitative comparison between the actual shape of the antenna and the original design shape. Accurately determining this shape also allows confident interpolation between the measured points. Such a model could, for example, be used for ray tracing of radio-frequency waves up to 95 GHz. to predict the performance of the antenna.

  12. Colour measurements of surfaces to evaluate the restoration materials

    Science.gov (United States)

    Lo Monaco, Angela; Marabelli, Maurizio; Pelosi, Claudia; Picchio, Rodolfo

    2011-06-01

    In this paper two case studies on the application of colour measurements for the evaluation of some restoration materials are discussed. The materials related to the research are: watercolours employed in restoration of wall paintings and preservative/consolidants for wood artifacts. Commercial watercolours, supplied by Maimeri, Windsor&Newton and Talens factories have been tested. Colour measurements have been performed by means of a reflectance spectrophotometer (RS) before and after accelerated ageing of watercolours at 92% relative humidity (RH) and in a Solar Box chamber. The experimental results show that watercolours based on natural earths and artificial ultramarine undergo the main colour changes, expressed as L*, a* and b* variations and total colour difference (▵E*). In the other cases colour differences depend on both watercolour typology and suppliers. The other example concerns the evaluation of colour change due to surface treatment of Poplar (Populus sp.) and chestnut (Castanea sativa L.) wood samples. The wooden samples have been treated with a novel organic preservative/consolidant product that has been tested also in a real case as comparison. The treated samples have been artificially aged in Solar Box chamber equipped with a 280 nm UV filter. Colour has been measured before and after the artificial ageing by means of a RS. Colour changes have been determined also for the main door of an historical mansion in Viterbo, made of chestnut wood, and exposed outdoors.

  13. Comparison of GOME-2/Metop-A ozone profiles with GOMOS, OSIRIS and MLS measurements

    Science.gov (United States)

    Määttä, A.; Tuinder, O. N. E.; Tukiainen, S.; Sofieva, V.; Tamminen, J.

    2015-07-01

    This paper presents a comparison of vertical ozone profiles retrieved by the Ozone ProfilE Retrieval Algorithm (OPERA) from the Global Ozone Monitoring Experiment 2 (GOME-2) measurements on board Metop-A with high-vertical-resolution ozone profiles by Global Ozone Monitoring by Occultation of Stars (GOMOS), Optical Spectrograph and Infrared Imager System (OSIRIS) and Microwave Limb Sounder (MLS). The comparison, with global coverage, focuses on the stratosphere and the lower mesosphere and covers the period from March 2008 until the end of 2011. The comparison shows an agreement of the GOME-2 ozone profiles with those of GOMOS, OSIRIS and MLS within ±15 % in the altitude range from 15 km up to ~ 35-40 km depending on latitude. The GOME-2 ozone profiles from non-degradation corrected radiances have a tendency to a systematic negative bias with respect to the reference data above ~ 30 km. The GOME-2 bias with respect to the high-vertical resolution instruments depends on season, with the strongest dependence observed at high latitudes.

  14. Advanced metrology of surface defects measurement for aluminum die casting

    Directory of Open Access Journals (Sweden)

    D. Myszka

    2011-07-01

    Full Text Available The scientific objective of the research is to develop a strategy to build computer based vision systems for inspection of surface defects inproducts, especially discontinuities which appear in castings after machining. In addition to the proposed vision inspection method theauthors demonstrates the development of the advanced computer techniques based on the methods of scanning to measure topography ofsurface defect in offline process control. This method allow to identify a mechanism responsible for the formation of casting defects. Also,the method allow investigating if the, developed vision inspection system for identification of surface defects have been correctlyimplemented for an online inspection. Finally, in order to make casting samples with gas and shrinkage porosity defects type, the LGT gas meter was used . For this task a special camera for a semi-quantitative assessment of the gas content in aluminum alloy melts, using a Straube-Pfeiffer method was used. The results demonstrate that applied solution is excellent tool in preparing for various aluminum alloysthe reference porosity samples, identified next by the computer inspection system.

  15. X-ray beam penetration in TXRF measurement of polycrystalline and amorphous surfaces

    International Nuclear Information System (INIS)

    Ghatak-Roy, A.R.; Hossain, T.Z.

    2000-01-01

    For TXRF measurement on single crystal silicon surface, it is generally agreed that the x-ray beam penetration is of the order of a few hundred Angstroms from the surface. However, for polycrystalline and amorphous surfaces - frequently used in semiconductor manufacturing there are evidences that x-rays penetrate much deeper revealing underlying layers. The evidences come from various measurements done with films such as silicon dioxide, silicon nitride and metal films such as aluminum, titanium and cobalt. A systematic study was carried out to help understand the issue further. Four sets of samples (on 8 inch wafers) were prepared to create layers buried under various deposited metal and non-metal layers. The metal layers created were aluminum, titanium and cobalt and the non-metal layers were silicon dioxide and silicon nitride. These samples were analyzed by TXRF under various angles and energies and the data were analyzed for signals from various buried layers along with their angular dependence. The results indicated deep penetration of x-ray beams. The samples were further analyzed by SIMS (Secondary Ion Mass Spectrometry) and some of them by ICP-MS (Inductively Coupled Plasma - Mass Spectrometry) to obtain information about their depth profiles. This was done in order to rule out the possibility of intermixing of layers during deposition. (author)

  16. Surface Acoustic Wave Vibration Sensors for Measuring Aircraft Flutter

    Science.gov (United States)

    Wilson, William C.; Moore, Jason P.; Juarez, Peter D.

    2016-01-01

    Under NASA's Advanced Air Vehicles Program the Advanced Air Transport Technology (AATT) Project is investigating flutter effects on aeroelastic wings. To support that work a new method for measuring vibrations due to flutter has been developed. The method employs low power Surface Acoustic Wave (SAW) sensors. To demonstrate the ability of the SAW sensor to detect flutter vibrations the sensors were attached to a Carbon fiber-reinforced polymer (CFRP) composite panel which was vibrated at six frequencies from 1Hz to 50Hz. The SAW data was compared to accelerometer data and was found to resemble sine waves and match each other closely. The SAW module design and results from the tests are presented here.

  17. Measurements of radial profiles of ion cyclotron resonance heating on the Tandem Mirror Experiment-Upgrade

    International Nuclear Information System (INIS)

    Falabella, S.

    1988-01-01

    A small Radial Energy Analyzer (REA) was used on the Tandem Mirror Experiment-Upgrade (TMX-U), at Lawerence Livermore National Laboratory, to investigate the radial profiles of ion temperature, density, and plasma potential during Ion Cyclotron Resonance Heating (ICRH). The probe has been inserted into the central-cell plasma at temperatures of 200 eV and densities of 3 x 10 12 cm/sup /minus 3// without damage to the probe, or major degradation of the plasma. This analyzer has indicated an increase in ion temperature from near 20 eV before ICRH to near 150 eV during ICRH, with about 60 kW of broadcast power. The REA measurements were cross-checked against other diagnostics on TMX-U and found to be consistent. The ion density measurement was compared to the line-density measured by microwave interferometry and found to agree within 10 to 20%. A radial intergral of n/sub i/T/sub i/ as measured by the REA shows good agreement with the diamagnetic loop measurement of plasma energy. The radial density profile is observed to broaden during the RF heating pulses, without inducing additional radial losses in the core plasma. The radial profile of plasma is seen to vary from axially peaked, to nearly flat as the plasma conditions carried over the series of experiments. To relate the increase in ion temperature to power absorbed by the plasma, a power balance as a function of radius was performed. The RF power absorbed is set equal to the sum of the losses during ICRH, minus those without ICRH. This method accounts for more than 70% of the broadcast power using a simple power balance model. The measured radial profile of the RF heating was compared to the calculations of two codes, ANTENA and GARFIELD, to test their effectiveness as predictors of power absorption profiles for TMX-U. 62 refs., 63 figs., 7 tabs

  18. The influence of profiled ceilings on sports hall acoustics : Ground effect predictions and scale model measurements

    NARCIS (Netherlands)

    Wattez, Y.C.M.; Tenpierik, M.J.; Nijs, L.

    2018-01-01

    Over the last few years, reverberation times and sound pressure levels have been measured in many sports halls. Most of these halls, for instance those made from stony materials, perform as predicted. However, sports halls constructed with profiled perforated steel roof panels have an unexpected

  19. Measuring Quality in Inclusive Preschool Classrooms: Development and Validation of the Inclusive Classroom Profile (ICP)

    Science.gov (United States)

    Soukakou, Elena P.

    2012-01-01

    The purpose of this study was to develop and validate an observation measure designed to assess classroom quality in inclusive preschool programs, the Inclusive Classroom Profile (ICP). Developing the rating scale entailed systematic fieldwork in inclusive settings and review of the literature on preschool inclusion. Results from the validation…

  20. Continuous measurements of discharge from a horizontal acoustic Doppler current profiler in a tidal river

    NARCIS (Netherlands)

    Hoitink, A.J.F.; Buschman, F.A.; Vermeulen, B.

    2009-01-01

    Acoustic Doppler current profilers (ADCPs) can be mounted horizontally at a river bank, yielding single-depth horizontal array observations of velocity across the river. This paper presents a semideterministic, semistochastic method to obtain continuous measurements of discharge from horizontal ADCP

  1. Magnetically Filtered Faraday Probe for Measuring the Ion Current Density Profile of a Hall Thruster

    National Research Council Canada - National Science Library

    Rovey, Joshua L; Walker, Mitchell L. R; Gallimore, Alec D; Peterson, Peter Y

    2006-01-01

    .... In this study, a MFFP, Faraday probe with a reduced acceptance angle (BFP), and nude Faraday probe are used to measure the ion current density profile of a 5 kW Hall thruster operating over the range of 300-500 V and 5-10 mg...

  2. Dose profile measurement in computerized axial tomography equipment using thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Azorin V, J.C.; Falcony, C.; Azorin N, J.

    2000-01-01

    In this work are presented the results about measuring the radiation dose profile in two equipment of computerized axial tomography (Tac). Thermoluminescent dosemeters (Dtl) of LiF, Mg, Cu, P + Ptfe in form of disks were used which were developed and made in Mexico. The results showed that Dtl are appropriated for these type of studies. (Author)

  3. Self-consistent electronic structure and segregation profiles of the Cu-Ni (001) random-alloy surface

    DEFF Research Database (Denmark)

    Ruban, Andrei; Abrikosov, I. A.; Kats, D. Ya.

    1994-01-01

    -density approximation. Temperature effects were accounted for by means of the cluster-variation method and, for comparison, by mean-field theory. The necessary interaction parameters were calculated by the Connolly-Williams method generalized to the case of a surface of a random alloy. We find the segregation profiles......We have calculated the electronic structure and segregation profiles of the (001) surface of random Cu-Ni alloys with varying bulk concentrations by means of the coherent potential approximation and the linear muffin-tin-orbitals method. Exchange and correlation were included within the local...

  4. Assessing the Expectations of Patients Demanding Rhinoplasty on Profile Photographs using Proportional Measurements and Simulation Programs

    Directory of Open Access Journals (Sweden)

    İsmail Küçüker

    2016-06-01

    Full Text Available Objective: The aim of this study was to define the desired profile measurements in patients who demand rhinoplasty and to assess the needs of extra profile surgeries in these patients. Material and Methods: Overall, 100 patients (60 women, 40 men demanding rhinoplasty between January and December 2013 were included in this study. Standard profile photos were taken. Rhinoplasty and extra profile surgeries were simulated in those photos with both patient and surgeon decisions. These simulated photos were assumed as the desired profile view. In those photos, some angles or measurements were calculated to understand the desired proportions on the profile view. Then, these desired proportions were compared with the universal ideal proportions to understand the needs of extra profile surgeries in those patients. Results: It has been found that 43% of women and 27.5% of men would benefit from fat injections to the forehead. Sagittal lowering of the nasion was necessary in 25% of both men and women. Respectively in women and men, demands in; nasolabial angle increase were 85% and 75%, projection increase according to Goode ratio were 35% and 32%, according to Baum ratio, 80 and 75%. Lower chins vertical height was longer than the nose in 18% and 17%, nose was longer than the lower chin in 17% and 7.5% in women and men respectively. Lower 2/3rds of the chin was longer than normal in 21% of the patients in both women and men. In two different proportions, the chin was found to be retruded in 23%–36% and 30%–35% and protruded in 23%–26% and 25%–30% in women and men, respectively. Conclusion: Personal demands may vary from the universal ideals. Therefore, pre-surgical simulations become necessary to assess the extra surgery needs in patients demanding rhinoplasty. These simulations may help the surgeon to personalize the surgery according to the patients demand, and patient satisfaction may increase as a result this approach.

  5. Diagnosis of the Course Vertical Profile of Radiative Heating with CERES Surface and Atmosphere Radiation Budget (SARB) for Terra and Aqua

    Science.gov (United States)

    Charlock, T. P.; Rose, F. G.; Rutan, D. A.

    2007-12-01

    The vertical profiles of SW and LW fluxes (surface, 500 hPa, 200 hPa, 70 hPa, and TOA) have been computed over the globe with the Langley Fu-Liou (FL) code and inputs for clouds from MODIS (Minnis et al.), aerosols from the MODIS-Atmosphere Team and the NCAR Model for Atmospheric Transport and Chemistry (MATCH), temperature and humidity from GEOS-4, and ozone from SMOBA (mostly SBUV). Surface spectral albedo for the ice-free ocean was based on Jin et al.; clear-sky broadband CERES SW observations and a look-up table to FL were used to develop surface albedo elsewhere. Tuned (i.e., based on adjustments to cloud properties) and untuned fluxes were compared with CERES at TOA for every footprint. Systematic validation with independent broadband SW and LW measurements at 60 sites worldwide has been a severe teacher on disparate accounts: RMS discrepancies of calculations with observations show that computed instantaneous diabatic profiles with clouds have limited meaning. For clear footprints over land, time-mean computed and observed surface insolations often agree, but this is partly due to offsetting errors in the code and aerosol inputs (MFRSR and Cimel photometers show MODIS Collection 4 land optical depths are too high). CERES broadband SW TOA observations appear to be low by 2-3 percent. Matched surface and TOA validation indicates, however, the LW profiles merit attention on the monthly scale: the interannual variability of surface LW downwelling compares astoundingly well with collocated ARM measurements of E13 and C01 (RMS of retrieval and measurement less than RMS of measurements). On both the interannual (deviation of an individual month from the calendar monthly mean) and synoptic (snapshot deviation from the mean of the individual month) scales, layer radiative heating correlates with layer water vapor more strongly than with layer temperature; and coherence in the upper troposphere exceeds that in the lower troposphere. Clouds introduce noise and reduce

  6. Research and application of online measurement system of tire tread profile in automobile tire production

    Science.gov (United States)

    Wang, Pengyao; Chen, Xiangguang; Yang, Kai; Liu, Xuejiao

    2017-01-01

    To improve the measuring efficiency of width and thickness of tire tread in the process of automobile tire production, the actual condition for the tire production process is analyzed, and a fast online measurement system based on moving tire tread of tire specifications is established in this paper. The coordinate data of tire tread profile is acquired by 3D laser sensor, and we use C# language for programming which is an object-oriented programming language to complete the development of client program. The system with laser sensor can provide real-time display of tire tread profile and the data to require in the process of tire production. Experimental results demonstrate that the measuring precision of the system is <= 1mm, it can meet the measurement requirements of the production process, and the system has the characteristics of convenient installation and testing, system stable operation.

  7. Measurement of dynamic wedge angles and beam profiles by means of MRI ferrous sulphate gel dosimetry

    Science.gov (United States)

    Bengtsson, Magnus; Furre, Torbjørn; Rødal, Jan; Skretting, Arne; Olsen, Dag R.

    1996-02-01

    The purpose of this study is to examine the possible value of measuring the dose distribution in dynamic wedge photon beams using ferrous sulphate gel phantoms analysed by MRI. The wedge angles and dose profiles were measured for a field size of and for dynamic wedge angles of , , and using a 15 MV photon beam generated from a Clinac 2100 CD (Varian). The dose profiles obtained from MRI ferrous sulphate gel were in good agreement with the dose measurements performed with a diode detector array. Also, the wedge angles determined from the MRI ferrous sulphate gel agreed well with the values obtained by using film dosimetry and with calculations by use of TMS (treatment planning system) (Helax, Uppsala, Sweden). The study demonstrated that MRI ferrous sulphate gel dosimetry is an adequate tool for measurements of some beam characteristics of dynamic radiation fields.

  8. First Experimental Results And Improvements On Profile Measurements With The Vibrating Wire Scanner

    CERN Document Server

    Arutunian, S G; Dobrovolski, N M; Mailian, M R; Soghoyan, H E; Vasiniuk, I E

    2003-01-01

    The paper presents the first experimental results of transverse profile scans using a wire scanner based on a vibrating wire (vibrating wire scanner - VWS). The measurements were performed at the injector electron beam (6 nA) of the Yerevan synchrotron. The beam profile information is obtained by measuring the wire natural oscillations that depend on the wire temperature. This first experiments on weak electron beam proved this new method as a very sensitive tool, even suitable for tail measurements. Additional, improvements were tested to overcome some problems connected with signal conditioning and signal transfer in the presence of electromagnetic noise. As a result the noises were neatly separated and reduced. A mathematical method for rejection of distorted data was developed. Experiments with the scanner at the PETRA accelerator at DESY are planned for measurements of beam tails.

  9. Channel Storage change: a new remote sensed surface water measurement

    Science.gov (United States)

    Coss, S. P.; Durand, M. T.; Yi, Y.; Guo, Q.; Shum, C. K.; Allen, G. H.; Pavelsky, T.

    2017-12-01

    Here we present river channel storage change (CSC) measurements for 17 major world rivers from 2002-2016. We combined interpolated daily 1 km resolution Global River Radar Altimeter Time Series (GRRATS) river surface elevation data with static widths from the global river Global River Widths from Landsat (GRWL) dataset, to generate preliminary channel storage measurements. CSC is a previously unmeasured component of the terrestrial water balance It is a fundamental Earth science quantity with global bearing on floodplains, ecology, and geochemistry. CSC calculations require only remote sensed data, making them an ideal tool for studying remote regions where hydrological data is not easily accessible. CSC is uniquely suited to determine the role of hydrologic and hydraulic controls in basins with strong seasonal cycles (freeze-up and break-up). The cumulative CSC anomaly can impart spatial details that discharge measurements cannot. With this new measurement, we may be able to determine critical hydrological and hydraulic controls on rapidly changing systems like Arctic rivers. Results for Mississippi River indicate that peak CSC anomaly was the highest in 2011 (12.6 km3) and minimum CSC anomaly was in 2012 (-12.2 km3). Peak CSC has most frequently occurs in May (5 years), but has come as late in the year as July, and as early as January. Results for the Yukon River indicate that peak CSC anomaly was the highest in 2013 (13.9 km3) and minimum CSC anomaly was in 2010 (-14.2 km3). Peak CSC has most frequently come in early to mid-June (4-18), but has occurred in May (19-31) four years in the study period (three of the last 6 years) and once on April 30th.

  10. Measuring sea surface height with a GNSS-Wave Glider

    Science.gov (United States)

    Morales Maqueda, Miguel Angel; Penna, Nigel T.; Foden, Peter R.; Martin, Ian; Cipollini, Paolo; Williams, Simon D.; Pugh, Jeff P.

    2017-04-01

    A GNSS-Wave Glider is a novel technique to measure sea surface height autonomously using the Global Navigation Satellite System (GNSS). It consists of an unmanned surface vehicle manufactured by Liquid Robotics, a Wave Glider, and a geodetic-grade GNSS antenna-receiver system, with the antenna installed on a mast on the vehicle's deck. The Wave Glider uses the differential wave motion through the water column for propulsion, thus guaranteeing an, in principle, indefinite autonomy. Solar energy is collected to power all on-board instrumentation, including the GNSS system. The GNSS-Wave Glider was first tested in Loch Ness in 2013, demonstrating that the technology is capable of mapping geoid heights within the loch with an accuracy of a few centimetres. The trial in Loch Ness did not conclusively confirm the reliability of the technique because, during the tests, the state of the water surface was much more benign than would normally be expect in the open ocean. We now report on a first deployment of a GNSS-Wave Glider in the North Sea. The deployment took place in August 2016 and lasted thirteen days, during which the vehicle covered a distance of about 350 nautical miles in the north western North Sea off Great Britain. During the experiment, the GNSS-Wave Glider experienced sea states between 1 (0-0.1 m wave heights) and 5 (2.5-4 m wave heights). The GNSS-Wave Glider data, recorded at 5 Hz frequency, were analysed using a post-processed kinematic GPS-GLONASS precise point positioning (PPP) approach, which were quality controlled using double difference GPS kinematic processing with respect to onshore reference stations. Filtered with a 900 s moving-average window, the PPP heights reveal geoid patterns in the survey area that are very similar to the EGM2008 geoid model, thus demonstrating the potential use of a GNSS-Wave Glider for marine geoid determination. The residual of subtracting the modelled or measured marine geoid from the PPP signal combines information

  11. Measuring surface temperature of isolated neutron stars and related problems

    Science.gov (United States)

    Teter, Marcus Alton

    New and exciting results for measuring neutron star surface temperatures began with the successful launch of the Chandra X-ray observatory. Among these results are new detections of neutron star surface temperatures which have made it possible to seriously test neutron star thermal evolution theories. The important new temperature determination of the Vela pulsar (Pavlov, et al., 2001a) requires a non-standard cooling scenario to explain it. Apart from this result, we have measured PSR B1055-52's surface temperature in this thesis, determining that it can be explained by standard cooling with heating. Our spectral fit of the combined data from ROSAT and Chandra have shown that a three component model, two thermal blackbodies and an non-thermal power-law, is required to explain the data. Furthermore, our phase resolved spectroscopy has begun to shed light on the geometry of the hot spot on PSR B1055-52's surface as well as the structure of the magnetospheric radiation. Also, there is strong evidence for a thermal distribution over its surface. Most importantly, the fact that PSR B1055-52 does not have a hydrogen atmosphere has been firmly established. To reconcile these two key observations, on the Vela pulsar and PSR B1055-52, we tested neutron star cooling with neutrino processes including the Cooper pair neutrino emission process. Overall, it has been found that a phase change associated with pions being present in the cores of more massive neutron stars explains all current of the data. A transition from neutron matter to pion condensates in the central stellar core explains the difference between standard and non-standard cooling scenarios, because the superfluid suppression of pion cooling will reduce the emissivity of the pion direct URCA process substantially. A neutron star with a mass of [Special characters omitted.] with a medium stiffness equation of state and a T72 type neutron superfluid models the standard cooling case well. A neutron star of [Special

  12. Surface current dynamics under sea breeze conditions observed by simultaneous HF radar, ADCP and drifter measurements

    Science.gov (United States)

    Sentchev, Alexei; Forget, Philippe; Fraunié, Philippe

    2017-04-01

    Ocean surface boundary layer dynamics off the southern coast of France in the NW Mediterranean is investigated by using velocity observations by high-frequency (HF) radars, surface drifting buoys and a downward-looking drifting acoustic Doppler current profiler (ADCP). The analysis confirms that velocities measured by HF radars correspond to those observed by an ADCP at the effective depth z f = k -1, where k is wavenumber of the radio wave emitted by the radar. The radials provided by the radars were in a very good agreement with in situ measurements, with the relative errors of 1 and 9 % and root mean square (RMS) differences of 0.02 and 0.04 m/s for monostatic and bistatic radar, respectively. The total radar-based velocities appeared to be slightly underestimated in magnitude and somewhat biased in direction. At the end of the survey period, the difference in the surface current direction, based on HF radar and ADCP data, attained 10°. It was demonstrated that the surface boundary layer dynamics cannot be reconstructed successfully without taking into the account velocity variation with depth. A significant misalignment of ˜30° caused by the sea breeze was documented between the HF radar (HFR-derived) surface current and the background current. It was also found that the ocean response to a moderate wind forcing was confined to the 4-m-thick upper layer. The respective Ekman current attained the maximum value of 0.15 m/s, and the current rotation was found to be lagging the wind by approximately 40 min, with the current vector direction being 15-20° to the left of the wind. The range of velocity variability due to wind forcing was found comparable with the magnitude of the background current variability.

  13. Sensitivity Analysis of Dune Height Measurements Along Cross-shore Profiles Using a Novel Method for Dune Ridge Extraction

    Science.gov (United States)

    Hardin, E.; Mitasova, H.; Overton, M.

    2010-12-01

    meets landward-facing slope. In this study, a novel approach for dune ridge extraction is proposed. First, two alongshore end-points of the studied dune ridge are identified using a standard, profile-based method. Then, the dune ridge is traced as the least cost path connecting the two end-points on a cost surface that represents the cumulative penalty for tracing a low elevation path. The cost surface is derived from elevation (i.e., elevation is equal to the cologarithm of the cost). The extracted dune ridge is then sampled at the DEM resolution of 0.5m and analysis of dune ridge height is performed. Statistics on variation in dune height are computed to help understand the sensitivity of dune height measurements to profile spacing and placement. Preliminary results suggest that dune height becomes nearly uncorrelated within 50m and ranges on average nearly a half meter within a five meter window suggesting that dune height measurements are sensitive to profile placement.

  14. Extrapolated surface dose measurements using a NdFeB magnetic deflector for 6 MV x-ray beams.

    Science.gov (United States)

    Damrongkijudom, N; Butson, M; Rosenfeld, A

    2007-03-01

    Extrapolated surface dose measurements have been performed using radiographic film to measure 2-Dimensional maps of skin and surface dose with and without a magnetic deflector device aimed at reducing surface dose. Experiments are also performed using an Attix parallel plate ionisation chamber for comparison to radiographic film extrapolation surface dose analysis. Extrapolated percentage surface dose assessments from radiographic film at the central axis of a 6 MV x-ray beam with magnetic deflector for field size 10 x 10 cm2, 15 x 15 cm2 and 20 x 20 cm2 are 9 +/- 3%, 13 +/- 3% and 16 +/- 3%, these compared to 14 +/- 3%, 19 +/- 3%, and 27 +/- 3% for open fields, respectively. Results from Attix chamber for the same field size are 12 +/- 1%, 15 +/- 1% and 18 +/- 1%, these compared to 16 +/- 1%, 21 +/- 1% and 27 +/- 1% for open fields, respectively. Results are also shown for profiles measured in-plane and cross-plane to the magnetic deflector and compared to open field data. Results have shown that the surface dose is reduced at all sites within the treatment field with larger reductions seen on one side of the field due to the sweeping nature of the designed magnetic field. Radiographic film extrapolation provides an advanced surface dose assessment and has matched well with Attix chamber results. Film measurement allows for easy 2 dimensional dose assessments.

  15. Visible imaging measurement of position and displacement of the last closed flux surface in EAST tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y.F. [School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China); Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Xu, G.S., E-mail: gsxu@ipp.ac.cn [School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China); Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Li, Y.L.; Yang, J.H.; Yan, N.; Liu, L.; Yuan, S.; Luo, Z.P. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Sang, C.F. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Gu, S.; Xu, J.C.; Hu, G.H.; Wang, Y.S. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Peng, Y.K.M.; Wan, B.N. [School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China); Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2017-06-15

    Highlights: • A new method for measuring the position and displacement of the LCFS has been developed in EAST tokamak. • This method is based on the visible imaging diagnostic and shown to be an effective and convenient approach. • This method can be applied to measure displacements of the LCFS during application of resonant magnetic perturbation fields. - Abstract: A new method for measuring the position and displacement of the last closed flux surface (LCFS) with visible imaging diagnostics has been developed in EAST. By measuring the relative intensity profiles of the green visible Li-II emission in the tangential planes of the optical systems, it is possible to infer the positions of certain points on the LCFS. This emission line is readily available in discharges with Li-coating wall routinely employed to improve the plasma performance. We describe the measuring method, giving results which are compared with those obtained by EFIT, and showing this as an effective and convenient approach to determine the position of the LCFS. This method is further applied to measure the displacements of the LCFS during application of resonant magnetic perturbation fields in the EAST tokamak.

  16. Ultrasonic Measurement of Velocity Profile on Bubbly Flow Using Fast Fourier Transform (FFT) Technique

    Science.gov (United States)

    Wongsaroj, W.; Hamdani, A.; Thong-un, N.; Takahashi, H.; Kikura, H.

    2017-10-01

    In two-phase bubbly flow, measurement of liquid and bubble velocity is a necessity to understand fluid characteristic. The conventional ultrasonic velocity profiler (UVP), which has been known as a nonintrusive measurement technique, can measure velocity profile of liquid and bubble simultaneously by applying a separation technique for both phases (liquid and bubble) and transparent test section is unnecessary. The aim of this study was to develop a new technique for separating liquid and bubble velocity data in UVP method to measure liquid and bubble velocity profiles separately. The technique employs only single resonant frequency transducer and a simple UVP system. An extra equipment is not required. Fast Fourier Transform (FFT) based frequency estimator paralleled with other signal processing techniques, which is called as proposed technique, was proposed to measure liquid and bubble velocity separately. The experimental facility of two-phase bubbly flow in the vertical pipe was constructed. Firstly, the Doppler frequency estimation by using the FFT technique was evaluated in single-phase liquid flow. Results showed that FFT technique showed a good agreement with autocorrelation and maximum likelihood estimator. Then, separation of liquid and bubble velocity was demonstrated experimentally in the two-phase bubbly flow. The proposed technique confirmed that liquid and bubble velocity could be measured efficiently.

  17. Comparison of predicted and measured pulsed-column profiles and inventories

    International Nuclear Information System (INIS)

    Ostenak, C.A.; Cermak, A.F.

    1983-01-01

    Nuclear materials accounting and process control in fuels reprocessing plants can be improved by near-real-time estimation of the in-process inventory in solvent-extraction contactors. Experimental studies were conducted on pilot- and plant-scale pulsed columns by Allied-General Nuclear Service (AGNS), and the extensive uranium concentration-profile and inventory data were analyzed by Los Alamos and AGNS to develop and evaluate different predictive inventory techniques. Preliminary comparisons of predicted and measured pulsed-column profiles and inventories show promise for using these predictive techniques to improve nuclear materials accounting and process control in fuels reprocessing plants

  18. 2D electron density profile measurement in tokamak by laser-accelerated ion-beam probe.

    Science.gov (United States)

    Chen, Y H; Yang, X Y; Lin, C; Wang, L; Xu, M; Wang, X G; Xiao, C J

    2014-11-01

    A new concept of Heavy Ion Beam Probe (HIBP) diagnostic has been proposed, of which the key is to replace the electrostatic accelerator of traditional HIBP by a laser-driven ion accelerator. Due to the large energy spread of ions, the laser-accelerated HIBP can measure the two-dimensional (2D) electron density profile of tokamak plasma. In a preliminary simulation, a 2D density profile was reconstructed with a spatial resolution of about 2 cm, and with the error below 15% in the core region. Diagnostics of 2D density fluctuation is also discussed.

  19. Comparison of GOME tropospheric NO2 columns with NO2 profiles deduced from ground-based in situ measurements

    Directory of Open Access Journals (Sweden)

    D. Schaub

    2006-01-01

    Full Text Available Nitrogen dioxide (NO2 vertical tropospheric column densities (VTCs retrieved from the Global Ozone Monitoring Experiment (GOME are compared to coincident ground-based tropospheric NO2 columns. The ground-based columns are deduced from in situ measurements at different altitudes in the Alps for 1997 to June 2003, yielding a unique long-term comparison of GOME NO2 VTC data retrieved by a collaboration of KNMI (Royal Netherlands Meteorological Institute and BIRA/IASB (Belgian Institute for Space Aeronomy with independently derived tropospheric NO2 profiles. A first comparison relates the GOME retrieved tropospheric columns to the tropospheric columns obtained by integrating the ground-based NO2 measurements. For a second comparison, the tropospheric profiles constructed from the ground-based measurements are first multiplied with the averaging kernel (AK of the GOME retrieval. The second approach makes the comparison independent from the a priori NO2 profile used in the GOME retrieval. This allows splitting the total difference between the column data sets into two contributions: one that is due to differences between the a priori and the ground-based NO2 profile shapes, and another that can be attributed to uncertainties in both the remaining retrieval parameters (such as, e.g., surface albedo or aerosol concentration and the ground-based in situ NO2 profiles. For anticyclonic clear sky conditions the comparison indicates a good agreement between the columns (n=157, R=0.70/0.74 for the first/second comparison approach, respectively. The mean relative difference (with respect to the ground-based columns is −7% with a standard deviation of 40% and GOME on average slightly underestimating the ground-based columns. Both data sets show a similar seasonal behaviour with a distinct maximum of spring NO2 VTCs. Further analysis indicates small GOME columns being systematically smaller than the ground-based ones. The influence of different shapes in the a

  20. GEOS-3 ocean current investigation using radar altimeter profiling. [Gulf Stream surface topography

    Science.gov (United States)

    Leitao, C. D.; Huang, N. E.; Parra, C. G.

    1978-01-01

    Both quasi-stationary and dynamic departures from the marine geoid were successfully detected using altitude measurements from the GEOS-3 radar altimeter. The quasi-stationary departures are observed either as elevation changes in single pass profiles across the Gulf Stream or at the crowding of contour lines at the western and northern areas of topographic maps generated using altimeter data spanning one month or longer. Dynamic features such as current meandering and spawned eddies can be monitored by comparing monthly mean maps. Comparison of altimeter inferred eddies with IR detected thermal rings indicates agreement of the two techniques. Estimates of current velocity are made using derived slope estimates in conjunction with the geostrophic equation.