WorldWideScience

Sample records for surface stations measurements

  1. Surface Flux Measurements at King Sejong Station in West Antarctica

    Science.gov (United States)

    Choi, T.; Lee, B.; Lee, H.; Shim, J.

    2004-12-01

    The Antarctic Peninsula is important in terms of global warming research due to pronounced increase of air temperature over the last century. The first eddy covariance system was established and turbulent fluxes of heat, water vapor, CO2 and momentum have been measured at King Sejong Station (62 \\deg 13øØS, 58 \\deg 47øØW) located in the northern edge of the Antarctic Peninsula since December in 2002. Our objectives are to better understand the interactions between the Antarctic land surface and the atmosphere and to test the feasibility of the long-term operation of eddy covariance system under extreme weather conditions. Various lichens cover the study area and the dominant species is Usnea fasciata-Himantormia. Based on the analyses on turbulent statistics such as integral turbulence characteristics of vertical velocity (w) and heat (T), stationarity test and investigation of correlation coefficient, they follow the Monin-Obukhov similarity and eddy covariance flux data were reliable. About 50 % of total retrieved sensible heat flux data could be used for further analysis. We will report on seasonal variations of energy and mass fluxes and environmental variables. In addition, factors controlling these fluxes will be presented. Acknowledgement: This study was supported by ¡rEnvironmental Monitoring on Human Impacts at the King Sejong Station, Antarctica¡_ (Project PP04102 of Korea Polar Research Institute) and ¡rEco-technopia 21 project¡_ (Ministry of Environment of Korea).

  2. On measuring surface wave phase velocity from station–station cross-correlation of ambient signal

    DEFF Research Database (Denmark)

    Boschi, Lapo; Weemstra, Cornelis; Verbeke, Julie

    2012-01-01

    We apply two different algorithms to measure surface wave phase velocity, as a function of frequency, from seismic ambient noise recorded at pairs of stations from a large European network. The two methods are based on consistent theoretical formulations, but differ in the implementation: one met...

  3. MEASUREMENT OF SURFACE SOLAR UV-B RADIATION AT TROPICAL COASTAL STATION BAKKHALI IN WEST BENGAL, INDIA

    OpenAIRE

    R. BHATTACHARYA; A. BHOUMICK

    2012-01-01

    Surface solar ultraviolet irradiance has been measured at Bakkhali (21.8ºN, 87.8ºE), a tropical rural station on the coast of Bay of Bengal, India in West Bengal. The measurements show a remarkable variation in UV-B load exists with a peak value at noon. The blockage of direct UV radiation in mangrove forest of costal site appears low when compared with UV load beneath the multiple trees of Mangifera indica in an inland site of Kalyani (22058' N, 88028' E), West Bengal. Mangrove forests have ...

  4. Multi-station synthesis of early twentieth century surface atmospheric electricity measurements for upper tropospheric properties

    Directory of Open Access Journals (Sweden)

    R. G. Harrison

    2007-07-01

    Full Text Available The vertical columnar current density in the global atmospheric electrical circuit depends on the local columnar resistance. A simple model for the columnar resistance is suggested, which separates the local boundary layer component from the upper troposphere cosmic ray component, and calculates the boundary layer component from a surface measurement of air conductivity. This theory is shown to provide reasonable agreement with observations. One application of the simple columnar model theory is to provide a basis for the synthesis of surface atmospheric electrical measurements made simultaneously at several European sites. Assuming the ionospheric potential to be common above all the sites, the theoretical air-earth current density present in the absence of a boundary layer columnar resistance can be found by extrapolation. This is denoted the free troposphere limit air-earth current density, J0. Using early surface data from 1909 when no ionospheric potential data are available for corroboration, J0 is found to be ~6 pA m−2, although this is subject to uncertainties in the data and limitations in the theory. Later (1966–1971 European balloon and surface data give J0=2.4 pA m−2.

  5. A Stabilizing Feedback Between Cloud Radiative Effects and Greenland Surface Melt: Verification From Multi-year Automatic Weather Station Measurements

    Science.gov (United States)

    Zender, C. S.; Wang, W.; van As, D.

    2017-12-01

    Clouds have strong impacts on Greenland's surface melt through the interaction with the dry atmosphere and reflective surfaces. However, their effects are uncertain due to the lack of in situ observations. To better quantify cloud radiative effects (CRE) in Greenland, we analyze and interpret multi-year radiation measurements from 30 automatic weather stations encompassing a broad range of climatological and topographical conditions. During melt season, clouds warm surface over most of Greenland, meaning the longwave greenhouse effect outweighs the shortwave shading effect; on the other hand, the spatial variability of net (longwave and shortwave) CRE is dominated by shortwave CRE and in turn by surface albedo, which controls the potential absorption of solar radiation when clouds are absent. The net warming effect decreases with shortwave CRE from high to low altitudes and from north to south (Fig. 1). The spatial correlation between albedo and net CRE is strong (r=0.93, palbedo determines the net CRE seasonal trend, which decreases from May to July and increases afterwards. On an hourly timescale, we find two distinct radiative states in Greenland (Fig. 2). The clear state is characterized by clear-sky conditions or thin clouds, when albedo and solar zenith angle (SZA) weakly correlates with CRE. The cloudy state is characterized by opaque clouds, when the combination of albedo and SZA strongly correlates with CRE (r=0.85, palbedo and solar zenith angle, explains the majority of the CRE variation in spatial distribution, seasonal trend in the ablation zone, and in hourly variability in the cloudy radiative state. Clouds warm the brighter and colder surfaces of Greenland, enhance snow melt, and tend to lower the albedo. Clouds cool the darker and warmer surfaces, inhibiting snow melt, which increases albedo, and thus stabilizes surface melt. This stabilizing mechanism may also occur over sea ice, helping to forestall surface melt as the Arctic becomes dimmer.

  6. Stage measurement at gaging stations

    Science.gov (United States)

    Sauer, Vernon B.; Turnipseed, D. Phil

    2010-01-01

    Stream and reservoir stage are critical parameters in the computation of stream discharge and reservoir volume, respectively. In addition, a record of stream stage is useful in the design of structures that may be affected by stream elevation, as well as for the planning for various uses of flood plains. This report describes equipment and methodology for the observation, sensing, and recording of stage in streams and reservoirs. Although the U.S. Geological Survey (USGS) still uses the traditional, basic stilling-well float system as a predominant gaging station, modern electronic stage sensors and water-level recorders are now commonly used. Bubble gages coupled with nonsubmersible pressure transducers eliminate the need for stilling wells. Submersible pressure transducers have become common in use for the measurement of stage in both rivers and lakes. Furthermore, noncontact methods, such as radar, acoustic, and laser methods of sensing water levels, are being developed and tested, and in the case of radar, are commonly used for the measurement of stage. This report describes commonly used gaging-station structures, as well as the design and operation of gaging stations. Almost all of the equipment and instruments described in this report will meet the accuracy standard set by the USGS Office of Surface Water (OSW) for the measurement of stage for most applications, which is ±0.01 foot (ft) or 0.2 percent of the effective stage. Several telemetry systems are used to transmit stage data from the gaging station to the office, although satellite telemetry has become the standard. These telemetry systems provide near real-time stage data, as well as other information that alerts the hydrographer to extreme or abnormal events, and instrument malfunctions.

  7. Near-surface ozone content at the Molodezhnaia and Mirnyi Antarctic stations, according to measurements made during spring 1987 to autumn 1988

    Energy Technology Data Exchange (ETDEWEB)

    Gruzdev, A.N.; Elokhov, A.S. (Rossiiskaia Akademiia Nauk, Institut Fiziki Atmosfery, Moscow (Russian Federation))

    1992-01-01

    Results are presented of near-surface ozone measurements at the Molodezhnaia and Mirnyi Antarctic stations, conducted from the spring of 1987 to the autumn of 1988, as well as of measurements by an aircraft flying along the Mirnyi-Vostok-Mirnyi path (one flight). Mechanisms of diurnal, day-to-day, and annual ozone variability are examined. It is found that, during synoptically active periods, the near-surface ozone correlates positively with the temperature above the atmosphere-land boundary layer, while during the synoptically quiet period the ozone concentrations correlate with the direction of the surface katabatic wind. 29 refs.

  8. Discharge measurements at gaging stations

    Science.gov (United States)

    Turnipseed, D. Phil; Sauer, Vernon B.

    2010-01-01

    The techniques and standards for making discharge measurements at streamflow gaging stations are described in this publication. The vertical axis rotating-element current meter, principally the Price current meter, has been traditionally used for most measurements of discharge; however, advancements in acoustic technology have led to important developments in the use of acoustic Doppler current profilers, acoustic Doppler velocimeters, and other emerging technologies for the measurement of discharge. These new instruments, based on acoustic Doppler theory, have the advantage of no moving parts, and in the case of the acoustic Doppler current profiler, quickly and easily provide three-dimensional stream-velocity profile data through much of the vertical water column. For much of the discussion of acoustic Doppler current profiler moving-boat methodology, the reader is referred to U.S. Geological Survey Techniques and Methods 3-A22 (Mueller and Wagner, 2009). Personal digital assistants (PDAs), electronic field notebooks, and other personal computers provide fast and efficient data-collection methods that are more error-free than traditional hand methods. The use of portable weirs and flumes, floats, volumetric tanks, indirect methods, and tracers in measuring discharge are briefly described.

  9. Simultaneous Determination of Structure and Event Location Using Body and Surface Wave Measurements at a Single Station: Preparation for Mars Data from the InSight Mission

    Science.gov (United States)

    Panning, M. P.; Banerdt, W. B.; Beucler, E.; Blanchette-Guertin, J. F.; Boese, M.; Clinton, J. F.; Drilleau, M.; James, S. R.; Kawamura, T.; Khan, A.; Lognonne, P. H.; Mocquet, A.; van Driel, M.

    2015-12-01

    An important challenge for the upcoming InSight mission to Mars, which will deliver a broadband seismic station to Mars along with other geophysical instruments in 2016, is to accurately determine event locations with the use of a single station. Locations are critical for the primary objective of the mission, determining the internal structure of Mars, as well as a secondary objective of measuring the activity of distribution of seismic events. As part of the mission planning process, a variety of techniques have been explored for location of marsquakes and inversion of structure, and preliminary procedures and software are already under development as part of the InSight Mars Quake and Mars Structure Services. One proposed method, involving the use of recordings of multiple-orbit surface waves, has already been tested with synthetic data and Earth recordings. This method has the strength of not requiring an a priori velocity model of Mars for quake location, but will only be practical for larger events. For smaller events where only first orbit surface waves and body waves are observable, other methods are required. In this study, we implement a transdimensional Bayesian inversion approach to simultaneously invert for basic velocity structure and location parameters (epicentral distance and origin time) using only measurements of body wave arrival times and dispersion of first orbit surface waves. The method is tested with synthetic data with expected Mars noise and Earth data for single events and groups of events and evaluated for errors in both location and structural determination, as well as tradeoffs between resolvable parameters and the effect of 3D crustal variations.

  10. Assessment of four methods to estimate surface UV radiation using satellite data, by comparison with ground measurements from four stations in Europe

    Science.gov (United States)

    Arola, Antti; Kalliskota, S.; den Outer, P. N.; Edvardsen, K.; Hansen, G.; Koskela, T.; Martin, T. J.; Matthijsen, J.; Meerkoetter, R.; Peeters, P.; Seckmeyer, G.; Simon, P. C.; Slaper, H.; Taalas, P.; Verdebout, J.

    2002-08-01

    Four different satellite-UV mapping methods are assessed by comparing them against ground-based measurements. The study includes most of the variability found in geographical, meteorological and atmospheric conditions. Three of the methods did not show any significant systematic bias, except during snow cover. The mean difference (bias) in daily doses for the Rijksinstituut voor Volksgezondheid en Milieu (RIVM) and Joint Research Centre (JRC) methods was found to be less than 10% with a RMS difference of the order of 30%. The Deutsches Zentrum für Luft- und Raumfahrt (DLR) method was assessed for a few selected months, and the accuracy was similar to the RIVM and JRC methods. It was additionally used to demonstrate how spatial averaging of high-resolution cloud data improves the estimation of UV daily doses. For the Institut d'Aéronomie Spatiale de Belgique (IASB) method the differences were somewhat higher, because of their original cloud algorithm. The mean difference in daily doses for IASB was about 30% or more, depending on the station, while the RMS difference was about 60%. The cloud algorithm of IASB has been replaced recently, and as a result the accuracy of the IASB method has improved. Evidence is found that further research and development should focus on the improvement of the cloud parameterization. Estimation of daily exposures is likely to be improved if additional time-resolved cloudiness information is available for the satellite-based methods. It is also demonstrated that further development work should be carried out on the treatment of albedo of snow-covered surfaces.

  11. Description of Measurements on Biogas Stations

    Directory of Open Access Journals (Sweden)

    Ladislav Novosád

    2016-08-01

    Full Text Available This paper focuses mainly on performance analysis for three biogas stations situated within the territory of the Czech Republic. This paper contains basic details of the individual biogas stations as well as description of their types. It also refers to the general description of the measurement gauge involved, with specifications of its potential use. The final part of this paper deals with the analysis of course data obtained, with special regard to voltage, current, active power and reactive power data.

  12. The surface physics work station: final design

    International Nuclear Information System (INIS)

    Landers, R.; Kleiman, G.G.; Castro, S.G.C. de; Douglas, R.A.; Nascente, P.A.P.

    1996-01-01

    Thanks to funding from FAPESP we will be installing in the beginning of 1997 a work station for electron spectroscopy designed for the study of clean solid surfaces and the modification of these surfaces by deposition in situ of ultra thin metallic films. The main analytical tool will be a high resolution hemispherical analyzer made by VSW-Omicrom (EA 125 HR) which is capable of better than 5 meV resolution and high transmission due to its five channeltron multi detection system. The system will also have a Rear View LEED Optics for single crystal studies. The system will be housed in a 16'' cylindrical chamber with mu metal magnetic shielding having two levels for analysis. The upper level will contain instruments for technique which do not require photons such as LEED and sample cleaning. The lower level will have the electron analyzer, conventional X-ray source (Al/Mg), electron gun for Auger, e-beam evaporators for thin film deposition and ports for the future addition of different detectors. We will have a manipulator with 5 degrees of freedom (thre translation and two rotational) and sample heating and LN cooling. Finally we will have a fast entry/preparation chamber. The pumping system will have a combination of turbomolecular and ion pumps for the main chamber and a turbo for the fast entr/prep chamber. The system will be used initially for the study of surface alloys by XPS and Photoelectron Diffraction but as soon as it is properly characterized it will be open for collaborations with other groups interested in using its capabilities. (author)

  13. Radiation measurements on the Mir Orbital Station

    International Nuclear Information System (INIS)

    Badhwar, G.D.; Atwell, W.; Reitz, G.; Beaujean, R.; Heinrich, W.

    2002-01-01

    Radiation measurements made onboard the MIR Orbital Station have spanned nearly a decade and covered two solar cycles, including one of the largest solar particle events, one of the largest magnetic storms, and a mean solar radio flux level reaching 250x10 4 Jansky that has been observed in the last 40 years. The cosmonaut absorbed dose rates varied from about 450 μGy day -1 during solar minimum to approximately half this value during the last solar maximum. There is a factor of about two in dose rate within a given module, and a similar variation from module to module. The average radiation quality factor during solar minimum, using the ICRP-26 definition, was about 2.4. The drift of the South Atlantic Anomaly was measured to be 6.0±0.5 deg. W, and 1.6±0.5 deg. N. These measurements are of direct applicability to the International Space Station. This paper represents a comprehensive review of Mir Space Station radiation data available from a variety of sources

  14. Radiation measurement on the International Space Station

    International Nuclear Information System (INIS)

    Akopova, A.B.; Manaseryan, M.M.; Melkonyan, A.A.; Tatikyan, S.Sh.; Potapov, Yu.

    2005-01-01

    The results of an investigation of radiation environment on board the ISS with apogee/perigee of 420/380km and inclination 51.6 o are presented. For measurement of important characteristics of cosmic rays (particles fluxes, LET spectrum, equivalent doses and heavy ions with Z>=2) a nuclear photographic emulsion as a controllable threshold detector was used. The use of this detector permits a registration of the LET spectrum of charged particles within wide range of dE/dx and during last years it has already been successfully used on board the MIR station, Space Shuttles and 'Kosmos' spacecrafts. An integral LET spectrum was measured in the range 0.5-2.2x103keV/μm and the value of equivalent dose 360μSv/day was estimated. The flux of biologically dangerous heavy particles with Z>=2 was measured (3.85x103particles/cm2)

  15. Surface science station of the infrared beamline at SPring-8

    International Nuclear Information System (INIS)

    Sakurai, M.; Moriwaki, T.; Kimura, H.; Nishida, S.; Nanba, T.

    2001-01-01

    An experimental station for surface science has been constructed at the infrared beamline (BL43IR) of SPring-8, Japan. The station utilizes synchrotron radiation in the energy range of 100-20000 cm -1 to perform infrared reflection absorption spectroscopy (IRAS) of surfaces. It consists of an experimental section, a preparation chamber, gas handling equipment and a pair of focusing optics. In situ observation of vibrational spectra is possible using both IRAS and high-resolution electron energy loss spectroscopy

  16. Surface and snowdrift sublimation at Princess Elisabeth station, East Antarctica

    Directory of Open Access Journals (Sweden)

    W. Thiery

    2012-08-01

    Full Text Available In the near-coastal regions of Antarctica, a significant fraction of the snow precipitating onto the surface is removed again through sublimation – either directly from the surface or from drifting snow particles. Meteorological observations from an Automatic Weather Station (AWS near the Belgian research station Princess Elisabeth in Dronning Maud Land, East-Antarctica, are used to study surface and snowdrift sublimation and to assess their impacts on both the surface mass balance and the surface energy balance during 2009 and 2010. Comparison to three other AWSs in Dronning Maud Land with 11 to 13 yr of observations shows that sublimation has a significant influence on the surface mass balance at katabatic locations by removing 10–23% of their total precipitation, but at the same time reveals anomalously low surface and snowdrift sublimation rates at Princess Elisabeth (17 mm w.e. yr−1 compared to 42 mm w.e. yr−1 at Svea Cross and 52 mm w.e. yr−1 at Wasa/Aboa. This anomaly is attributed to local topography, which shields the station from strong katabatic influence, and, therefore, on the one hand allows for a strong surface inversion to persist throughout most of the year and on the other hand causes a lower probability of occurrence of intermediately strong winds. This wind speed class turns out to contribute most to the total snowdrift sublimation mass flux, given its ability to lift a high number of particles while still allowing for considerable undersaturation.

  17. Measuring stations for gamma radiation - measured results 1982

    International Nuclear Information System (INIS)

    Kjelle, P.E.

    1983-01-01

    Gamma radiation is recorded continuously at 25 stations in Sweden. The evaluation of the data from five of the stations is made in a most accurate way, and the results are presented in this report. (G.B.)

  18. Measurement of complex surfaces

    International Nuclear Information System (INIS)

    Brown, G.M.

    1993-05-01

    Several of the components used in coil fabrication involve complex surfaces and dimensions that are not well suited to measurements using conventional dimensional measuring equipment. Some relatively simple techniques that are in use in the SSCL Magnet Systems Division (MSD) for incoming inspection will be described, with discussion of their suitability for specific applications. Components that are submitted for MSD Quality Assurance (QA) dimensional inspection may be divided into two distinct categories; the first category involves components for which there is an approved drawing and for which all nominal dimensions are known; the second category involves parts for which 'reverse engineering' is required, the part is available but there are no available drawings or dimensions. This second category typically occurs during development of coil end parts and coil turn filler parts where it is necessary to manually shape the part and then measure it to develop the information required to prepare a drawing for the part

  19. Magnetic field measurements near stand-alone transformer stations.

    Science.gov (United States)

    Kandel, Shaiela; Hareuveny, Ronen; Yitzhak, Nir-Mordechay; Ruppin, Raphael

    2013-12-01

    Extremely low-frequency (ELF) magnetic field (MF) measurements around and above three stand-alone 22/0.4-kV transformer stations have been performed. The low-voltage (LV) cables between the transformer and the LV switchgear were found to be the major source of strong ELF MFs of limited spatial extent. The strong fields measured above the transformer stations support the assessment method, to be used in future epidemiological studies, of classifying apartments located right above the transformer stations as highly exposed to MFs. The results of the MF measurements above the ground around the transformer stations provide a basis for the assessment of the option of implementing precautionary procedures.

  20. Measuring Robustness of Timetables at Stations using a Probability Distribution

    DEFF Research Database (Denmark)

    Jensen, Lars Wittrup; Landex, Alex

    Stations are often the limiting capacity factor in a railway network. This induces interdependencies, especially at at-grade junctions, causing network effects. This paper presents three traditional methods that can be used to measure the complexity of a station, indicating the robustness...... of the station’s infrastructure layout and plan of operation. However, these three methods do not take the timetable at the station into consideration. Therefore, two methods are introduced in this paper, making it possible to estimate the robustness of different timetables at a station or different...... infrastructure layouts given a timetable. These two methods provide different precision at the expense of a more complex calculation process. The advanced and more precise method is based on a probability distribution that can describe the expected delay between two trains as a function of the buffer time...

  1. Seasonal features of black carbon measured at Syowa Station, Antarctica

    Science.gov (United States)

    Hara, K.; Osada, K.; Yabuki, M.; Shiobara, M.; Yamanouchi, T.

    2015-12-01

    Black carbon (BC) is one of important aerosol constituents because the strong light absorption ability. Low concentrations of aerosols and BC let BC make insignificant contribution to aerosol radiative forcing in the Antarctica at the moment. Because of less or negligible source strength of BC in the Antarctic circle, BC can be used as a tracer of transport from the mid-latitudes. This study aims to understand seasonal feature, transport pathway, and origins of black carbon in the Antarctic coats. Black carbon measurement has been made using 7-wavelength aethalometer at Syowa Station, Antarctica since February, 2005. Mass BC concentrations were estimated from light attenuation by Weingartner's correction procedure (Weingartner et al., 2003) in this study. Detection limit was 0.2 - 0.4 ng/m3 in our measurement conditions (2-hour resolution and flow rate of ca. 10LPM). BC concentrations ranged from near detection limit to 55.7 ng/m3 at Syowa Station, Antarctica during the measurements. No trend has been observed since February, 2005. High BC concentrations were coincident with poleward flow from the mid-latitudes under the storm conditions by cyclone approach, whereas low BC concentrations were found in transport from coastal regions and the Antarctic continent. Considering that outflow from South America and Southern Africa affect remarkably air quality in the Southern Ocean of Atlantic and Indian Ocean sectors, BC at Syowa Station might be originated from biomass burning and human activity on South America and Southern Africa. Seasonal features of BC at Syowa Station shows maximum in September - October and lower in December - April. Spring maximum in September - October was obtained at the other Antarctic stations (Neumayer, Halley, South pole, and Ferraz). Although second maximum was found in January at the other stations, the maximum was not observed at Syowa Station.

  2. Mine alarm stations for mine haulage systems in coal surface mines. Stantsiya pozharnoi signalizatsii dlya gorno-transportnogo oborudovaniya ugol'nykh razrezov

    Energy Technology Data Exchange (ETDEWEB)

    Terebilo, N.I.; Bukhanets, B.N.; Rozhkov, V.L.; Martynenko, V.D. (Vsesoyuznyi Nauchno-Issledovatel' skii Institut Gornospasatel' nogo Dela, Donetsk (USSR))

    1988-01-01

    Describes design and operation of the STs fire alarm station developed by the Spetsavtomatika plant in Minsk and successfully tested in the Borodino surface coal mine. The station consists of 14 measuring circuits with the measuring cycle not longer than 4 s. The station detects fires at earthmoving and haulage equipment, cuts off energy supply to fire zones and activates fire extinguishing equipment. The station will be manufactured on a commercial scale. 2 refs.

  3. Measurement of surface roughness

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This document is used in connection with two 3 hours laboratory exercises that are part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The laboratories include a demonstration of the function of roughness measuring instruments plus a series of exercises illustrating roughness measurement...

  4. Preliminary measurements of gamma radiation in Chilean Antarctic Stations

    Energy Technology Data Exchange (ETDEWEB)

    Stuardo B, E. (Comision Chilena de Energia Nuclear, Santiago. Dept. de Aplicaciones Nucleares)

    1983-11-01

    Natural and artificial gamma radiation, 1 m above the soil, is being investigated in 4 Chilean Antartic Stations. The measurements are performed with different types of TLD detectors. Preliminary results in the Tte. Marsh Station are reported and discussed. An average exposition of 3,5 ..mu..R/h was found during a 108 days period. This exposition corresponds to an annual dose of about 40 mrad, 8% of the annual dose limit for individual of the public. The presence of low energy artificial radioisotopes was not found.

  5. Preliminary measurements of gamma radiation in Chilean Antarctic Stations

    International Nuclear Information System (INIS)

    Stuardo B, E.

    1983-01-01

    Natural and artificial gamma radiation, 1 m above the soil, is being investigated in 4 Chilean Antartic Stations. The measurements are performed with different types of TLD detectors. Preliminary results in the Tte. Marsh Station are reported and discussed. An average exposition of 3,5 μR/h was found during a 108 days period. This exposition corresponds to an annual dose of about 40 mrad, 8% of the annual dose limit for individual of the public. The presence of low energy artificial radioisotopes was not found. (Author)

  6. Radon Measurements in underground metro stations in Cairo City, Egypt

    International Nuclear Information System (INIS)

    Hafez, A.F.; Hussein, A.S.; Rasheed, N.M.

    2000-01-01

    Radon activity concentration were measured continuously during the year 1998-1999 at two different underground MERTO stations, namely, Mubarak and El-Sadat. The measurements were performed using the diffusion cups equipped with CR-39 and LR-115 polymeric nuclear track detectors. Using the experimentally measured calibration coefficients of the used detectors and the measured track densities (bare and filtered), the yearly mean radon concentration C=23 Bq m -3 , equilibrium factor F= 0,10 and effective dose E=0,06 mSv y -1 for the employed personal as well as E=5 mu Sv y -1 for the commuter were obtained

  7. Test Station for Measuring Aluminum Tube Geometrical Parameters

    CERN Document Server

    Oansea, D; Gongadze, A L; Gostkin, M I; Dedovich, D V; Evtoukhovitch, P G; Comanescu, B; Kotov, S A; Necsoiu, T; Potrap, I N; Rogalev, E V; Tskhadadze, E G; Chelkov, G A

    2001-01-01

    A test station for quality control of aluminum tube outer diameter and wall thickness is presented. The tested tubes are used for drift detector assembly of ATLAS (LHC, CERN) muon system. The outer diameter and wall thickness of aluminium tubes are measured by means of noncontact optical and ultrasonic methods respectively with the accuracy of 3 {\\mu}m. The testing process is automatic and interacts with the production data base.

  8. 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...

  9. Measurements of Electromagnetic Fields Emitted from Cellular Base Stations in

    Directory of Open Access Journals (Sweden)

    K. J. Ali

    2013-05-01

    Full Text Available With increasing the usage of mobile communication devices and internet network information, the entry of private telecommunications companies in Iraq has been started since 2003. These companies began to build up cellular towers to accomplish the telecommunication works but they ignore the safety conditions imposed for the health and environment that are considered in random way. These negative health effects which may cause a health risk for life beings and environment pollution. The aim of this work is to determine the safe and unsafe ranges and discuss damage caused by radiation emitted from Asia cell base stations in Shirqat city and discuses the best ways in which can be minimize its exposure level to avoid its negative health effects. Practical measurements of power density around base stations has been accomplished by using a radiation survey meter type (Radio frequency EMF Strength Meter 480846 in two ways. The first way of measurements has been accomplished at a height of 2 meters above ground for different distances from (0-300 meters .The second way is at a distance of 150 meters for different levels from (2-15 meters above ground level. The maximum measured power density is about (3 mW/m2. Results indicate that the levels of power density are far below the RF radiation exposure of USSR safety standards levels. And that means these cellular base station don't cause negative the health effect for life being if the exposure is within the acceptable international standard levels.

  10. Artefacts for optical surface measurement

    Science.gov (United States)

    Robson, Stuart; Beraldin, J.-Angelo; Brownhill, Andrew; MacDonald, Lindsay

    2011-07-01

    Flexible manufacturing technologies are supporting the routine production of components with freeform surfaces in a wide variety of materials and surface finishes. Such surfaces may be exploited for both aesthetic and performance criteria for a wide range of industries, for example automotive, aircraft, small consumer goods and medial components. In order to ensure conformance between manufactured part and digital design it is necessary to understand, validate and promote best practice of the available measurement technologies. Similar, but currently less quantifiable, measurement requirements also exist in heritage, museum and fine art recording where objects can be individually hand crafted to extremely fine levels of detail. Optical 3D measurement systems designed for close range applications are typified by one or more illumination sources projecting a spot, line or structured light pattern onto a surface or surfaces of interest. Reflections from the projected light are detected in one or more imaging devices and measurements made concerning the location, intensity and optionally colour of the image. Coordinates of locations on the surface may be computed either directly from an understanding of the illumination and imaging geometry or indirectly through analysis of the spatial frequencies of the projected pattern. Regardless of sensing configuration some independent means is necessary to ensure that measurement capability will meet the requirements of a given level of object recording and is consistent for variations in surface properties and structure. As technologies mature, guidelines for best practice are emerging, most prominent at the current time being the German VDI/VDE 2634 and ISO/DIS 10360-8 guidelines. This considers state of the art capabilities for independent validation of optical non-contact measurement systems suited to the close range measurement of table top sized manufactured or crafted objects.

  11. Thermoluminescent dose measurements on board Salyut type orbital stations

    International Nuclear Information System (INIS)

    Akatov, Yu.A.; Arkhangelskij, V.V.; Aleksandrov, A.P.

    1984-06-01

    A small, vibration- and shock-resistant thermoluminescent dosemeter (TLD) system - named PILLE - was developed for orbital stations at the Central Research Institute for Physics, Hungary, to measure the cosmic radiation dose on-board. The first on-board measurements with this system were performed by B. Farkas, the Hungarian astronaut, on the Salyut-6 space station in 1980. The same instrument was used by other crews in the following years. Doses measured at different sites in Salyut-6 are presented. The dose rates varied from 0.7 to 0.11 mGy.day -1 . After the first cosmic measurements, the system was further developed. The minimum detectable dose of the new TLD system is 1 μGy, i.e. less by one order of magnitude than that of the former system. The self-irradiation dose rate of the TLD bulbs is also reduced by more than an order of magnitude to 10 nGy.h -1 , by use of potassium-free glass for the bulb envelope. This new type of PILLE TLD system is currently on-board Salyut-7. The dose rates (0.12-0.23 mGy.day -1 ) measured in 1983 are presented in detail. (author)

  12. Transportable IOT measurement station for direct-broadcast satellites

    Science.gov (United States)

    Ulbricht, Michael

    A transportable 11.7-12.5-GHz flux-density measurement facility for use in the in-orbit testing (IOT) of the FRG TV-Sat direct-broadcast satellites is described. Major components include a 1.2-m-diameter antenna, the fluxmeter, a radiometer to determine atmospheric attenuation, a weather station, and a control and data-processing computer; all of the components are mounted on a 5.10 x 2.35 x 2.70-m trailer. IOT performance parameters include gain/temperature ratio 15.9 dB/K, measurement range -97 to -117 dBW/sq m, measurement accuracy less than 0.5 dB rms, and measurement rate 250-650 msec. Photographs and a block diagram are provided.

  13. The use of automatic weather stations to measure the soil temperature in the Mordovia State Nature Reserve (Russia) in 2016

    OpenAIRE

    Oleg G. Grishutkin

    2017-01-01

    The article presents the soil temperature data obtained using two automatic weather stations located in the Mordovia State Nature Reserve (Russia). Measurements were carried out at the soil surface and at depths of 20 cm, 40 cm and 60 cm. The meteorological stations are located 15 km apart, in general, in similar landscapes. This caused similar results of meteorological measurements. Differences in the average of the daily temperature at corresponding depths are less than 2°C. The average ann...

  14. Information measuring subsystem oil pumping station “Parabel”

    Directory of Open Access Journals (Sweden)

    Nyashina Galina S.

    2014-01-01

    Full Text Available Information-measurement subsystem oil pumping station (OPS “Parabel”, located on the site of the main pipeline “Alexandrov-Anzhero” (OJSC “AK” Transneft "”. Developed on the basis of a modern microprocessor equipment, automation, as well as high-speed digital data channels. The simple solution to meet the requirements set out in the guidance document "Automation and remote control of trunk pipelines. «General provisions» (RD-35.240.0000-KTN-207-08.

  15. SEE in-flight measurement on the MIR orbital station

    International Nuclear Information System (INIS)

    Falguere, D.; Duzellier, S.; Ecoffet, R.

    1994-01-01

    SEE spaceflight measurements are presented on HM65756 SRAM from Matra-MHS, Seeq 28C256 and Motorola MC68020 microprocessor (bulk version) in the MIR station orbit (350 km altitude, 51.6 degree inclination). Accelerator testing (heavy ion and proton) of flight spares permits the prediction of the event rates using standard model such as CREME and SPACERAD as well as characterizations of the flight components allowing the comparison of in-orbit observations. Event rate prediction and ground-testing data are compared

  16. Validation of AIRS V6 Surface Temperature over Greenland with GCN and NOAA Stations

    Science.gov (United States)

    Lee, Jae N.; Hearty, Thomas; Cullather, Richard; Nowicki, Sophie; Susskind, Joel

    2016-01-01

    This work compares the temporal and spatial characteristics of the AIRSAMSU (Atmospheric Infrared Sounder Advanced Microwave Sounding Unit A) Version 6 and MODIS (Moderate resolution Imaging Spectroradiometer) Collection 5 derived surface temperatures over Greenland. To estimate uncertainties in space-based surface temperature measurements, we re-projected the MODIS Ice Surface Temperature (IST) to 0.5 by 0.5 degree spatial resolution. We also re-gridded AIRS Skin Temperature (Ts) into the same grid but classified with different cloud conditions and surface types. These co-located data sets make intercomparison between the two instruments relatively straightforward. Using this approach, the spatial comparison between the monthly mean AIRS Ts and MODIS IST is in good agreement with RMS 2K for May 2012. This approach also allows the detection of any long-term calibration drift and the careful examination of calibration consistency in the MODIS and AIRS temperature data record. The temporal correlations between temperature data are also compared with those from in-situ measurements from GC-Net (GCN) and NOAA stations. The coherent time series of surface temperature evident in the correlation between AIRS Ts and GCN temperatures suggest that at monthly time scales both observations capture the same climate signal over Greenland. It is also suggested that AIRS surface air temperature (Ta) can be used to estimate the boundary layer inversion.

  17. Evaluation of Arctic broadband surface radiation measurements

    Science.gov (United States)

    Matsui, N.; Long, C. N.; Augustine, J.; Halliwell, D.; Uttal, T.; Longenecker, D.; Niebergall, O.; Wendell, J.; Albee, R.

    2012-02-01

    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.

  18. Independent measuring station for the GNEJS neutron spectrometer information and measurement system

    International Nuclear Information System (INIS)

    Gorokhov, I.S.; Laptev, A.B.; Marchenkov, V.V.; Tubol'tsev, Yu.V.; Fokin, E.Yu.; Shcherbakov, O.A.

    1984-01-01

    An independent measuring station (IMS) being a part of the information and measuring system of the neutron time-of-flight spectrometer is described. IMS represents the time (time-to-amplitude or time-to-angular) module analyzer assembled on the base of one or several CAMAC crates. The station permits to perform time measurements as well as the time measurements with amplitude weighing in an independent mode with subseqUent data transmission the central PDP-11/05 computer. The station processor unit is an independent controller. The software consists of the programming langUage of the controller from local terminal and programs ensuring measuring and shaping the spectra with their output on TV display devic. communication with the computer and dialogue with the operator

  19. Surface flow measurements from drones

    Science.gov (United States)

    Tauro, Flavia; Porfiri, Maurizio; Grimaldi, Salvatore

    2016-09-01

    Drones are transforming the way we sense and interact with the environment. However, despite their increased capabilities, the use of drones in geophysical sciences usually focuses on image acquisition for generating high-resolution maps. Motivated by the increasing demand for innovative and high performance geophysical observational methodologies, we posit the integration of drone technology and optical sensing toward a quantitative characterization of surface flow phenomena. We demonstrate that a recreational drone can be used to yield accurate surface flow maps of sub-meter water bodies. Specifically, drone's vibrations do not hinder surface flow observations, and velocity measurements are in agreement with traditional techniques. This first instance of quantitative water flow sensing from a flying drone paves the way to novel observations of the environment.

  20. Method of measuring surface density

    International Nuclear Information System (INIS)

    Gregor, J.

    1982-01-01

    A method is described of measuring surface density or thickness, preferably of coating layers, using radiation emitted by a suitable radionuclide, e.g., 241 Am. The radiation impinges on the measured material, e.g., a copper foil and in dependence on its surface density or thickness part of the flux of impinging radiation is reflected and part penetrates through the material. The radiation which has penetrated through the material excites in a replaceable adjustable backing characteristic radiation of an energy close to that of the impinging radiation (within +-30 keV). Part of the flux of the characteristic radiation spreads back to the detector, penetrates through the material in which in dependence on surface density or thickness of the coating layer it is partly absorbed. The flux of the penetrated characteristic radiation impinging on the face of the detector is a function of surface density or thickness. Only that part of the energy is evaluated of the energy spectrum which corresponds to the energy of characteristic radiation. (B.S.)

  1. Passive dosimetry aboard the Mir Orbital Station: internal measurements

    International Nuclear Information System (INIS)

    Benton, E.R.; Benton, E.V.; Frank, A.L.

    2002-01-01

    Passive radiation dosimeters were exposed aboard the Mir Orbital Station over a substantial portion of the solar cycle in order to measure the change in dose and dose equivalent rates as a function of time. During solar minimum, simultaneous measurements of the radiation environment throughout the habitable volume of the Mir were made using passive dosimeters in order to investigate the effect of localized shielding on dose and dose equivalent. The passive dosimeters consisted of a combination of thermoluminescent detectors to measure absorbed dose and CR-39 PNTDs to measure the linear energy transfer (LET) spectrum from charged particles of LET ∞ H 2 O≥5 keV/μm. Results from the two detector types were then combined to yield mean total dose rate, mean dose equivalent rate, and average quality factor. Contrary to expectations, both dose and dose equivalent rates measured during May-October 1991 near solar maximum were higher than similar measurements carried out in 1996-1997 during solar minimum. The elevated dose and dose equivalent rates measured in 1991 were probably due to a combination of intense solar activity, including a large solar particle event on 9 June 1991, and the temporary trapped radiation belt created in the slot region by the solar particle event and ensuing magnetic storm of 24 March 1991. During solar minimum, mean dose and dose equivalent rates were found to vary by factors of 1.55 and 1.37, respectively, between different locations through the interior of Mir. More heavily shielded locations tended to yield lower total dose and dose equivalent rates, but higher average quality factor than did more lightly shielding locations. However, other factors such as changes in the immediate shielding environment surrounding a given detector location, changes in the orientation of the Mir relative to its velocity vector, and changes in the altitude of the station also contributed to the variation. Proton and neutron-induced target fragment

  2. Optical measurements on contaminated surfaces

    Science.gov (United States)

    Bonham, T. E.; Schmitt, R. J.; Linford, R. M. F.

    1975-01-01

    A bidirectional reflectometer system was developed for in situ measurements of the changes in spectral reflectance of surfaces contaminated with films of organic materials. The system permits experiments with films of controlled thickness in an environment that simulates the thermal, radiation, and vacuum conditions of space. The mechanical and optical construction of the reflectometer are discussed in detail, and actual data curves are used to illustrate its operation and performance.

  3. 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.

  4. Challenges to fire protection measures at Hamaoka Nuclear Power Station

    International Nuclear Information System (INIS)

    Narama, Takeshi

    2015-01-01

    New regulatory standards for fire protection at nuclear power plants have been established by the Nuclear Regulation Authority. This paper introduces the measures taken by the Hamaoka Nuclear Power Station for the following four items, which were especially big changes. (1) To install a combination of sensors of different types or instruments with equivalent functions so as to be able to emit unique signals to inform a fire in the early stage. (2) To conduct 'UL vertical burn test' as the demonstration test for self-extinguishing performance as the condition for flame-retardant cable. (3) To install automatic fire-extinguishers or fixed fire-extinguishing devices of manual type at the spots where fire-fighting is difficult due to the filling of smoke in a fire or the effect of radiation. (4) To separate the system for purpose of ensuring safety function to attain the high-temperature shutdown and cold-temperature shutdown of a reactor whatever fire may happen at the nuclear facilities. The examples of the installation of fire-extinguishers as the measures for the above Item (3) are as follows; (A) as for the devices containing oil, a foam-extinguishing agent is released against each target device from the nozzle, and (B) for large vertical pump motors indoors and relatively small pump motors, IA type automatic foam extinguishing systems are installed. (A.O.)

  5. Diurnal variability of surface fluxes at an oceanic station in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, Y.V.B.; Rao, D.P.

    Diurnal variability of the surface fluxes and ocean heat content was studied using the time-series data on marine surface meteorological parameters and upper ocean temperature collected at an oceanic station in the Bay of Bengal during 1st to 8th...

  6. 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.

  7. Near-station terrain corrections for gravity data by a surface-integral technique

    Science.gov (United States)

    Gettings, M.E.

    1982-01-01

    A new method of computing gravity terrain corrections by use of a digitizer and digital computer can result in substantial savings in the time and manual labor required to perform such corrections by conventional manual ring-chart techniques. The method is typically applied to estimate terrain effects for topography near the station, for example within 3 km of the station, although it has been used successfully to a radius of 15 km to estimate corrections in areas where topographic mapping is poor. Points (about 20) that define topographic maxima, minima, and changes in the slope gradient are picked on the topographic map, within the desired radius of correction about the station. Particular attention must be paid to the area immediately surrounding the station to ensure a good topographic representation. The horizontal and vertical coordinates of these points are entered into the computer, usually by means of a digitizer. The computer then fits a multiquadric surface to the input points to form an analytic representation of the surface. By means of the divergence theorem, the gravity effect of an interior closed solid can be expressed as a surface integral, and the terrain correction is calculated by numerical evaluation of the integral over the surfaces of a cylinder, The vertical sides of which are at the correction radius about the station, the flat bottom surface at the topographic minimum, and the upper surface given by the multiquadric equation. The method has been tested with favorable results against models for which an exact result is available and against manually computed field-station locations in areas of rugged topography. By increasing the number of points defining the topographic surface, any desired degree of accuracy can be obtained. The method is more objective than manual ring-chart techniques because no average compartment elevations need be estimated ?

  8. Diurnal and seasonal variations in surface methane at a tropical coastal station: Role of mesoscale meteorology.

    Science.gov (United States)

    Kavitha, M; Nair, Prabha R; Girach, I A; Aneesh, S; Sijikumar, S; Renju, R

    2018-08-01

    In view of the large uncertainties in the methane (CH 4 ) emission estimates and the large spatial gaps in its measurements, studies on near-surface CH 4 on regional basis become highly relevant. This paper presents the first time observational results of a study on the impacts of mesoscale meteorology on the temporal variations of near-surface CH 4 at a tropical coastal station, in India. It is based on the in-situ measurements conducted during January 2014 to August 2016, using an on-line CH 4 analyzer working on the principle of gas chromatography. The diurnal variation shows a daytime low (1898-1925ppbv) and nighttime high (1936-2022ppbv) extending till early morning hours. These changes are closely associated with the mesoscale circulations, namely Sea Breeze (SB) and Land Breeze (LB), as obtained through the meteorological observations, WRF simulations of the circulations and the diurnal variation of boundary layer height as observed by the Microwave Radiometer Profiler. The diurnal enhancement always coincides with the onset of LB. Several cases of different onset timings of LB were examined and results presented. The CH 4 mixing ratio also exhibits significant seasonal patterns being maximum in winter and minimum in pre-monsoon/monsoon with significant inter-annual variations, which is also reflected in diurnal patterns, and are associated with changing synoptic meteorology. This paper also presents an analysis of in-situ measured near-surface CH 4 , column averaged and upper tropospheric CH 4 retrieved by Atmospheric Infrared Sounder (AIRS) onboard Earth Observing System (EOS)/Aqua which gives insight into the vertical distribution of the CH 4 over the location. An attempt is also made to estimate the instantaneous radiative forcing for the measured CH 4 mixing ratio. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Electromagnetic fields from base stations for cellular mobile telephones. Measurements around base stations in the Oslo area

    International Nuclear Information System (INIS)

    Hannevik, Merete

    2000-01-01

    Measurements of radio frequent radiation from base station antennas for cellular mobile telephony have been performed. Measurements were performed inside the buildings in the area just behind or below antennas mounted on the wall or rooftop on buildings and on the ground below tower-mounted antennas. Except from the area 2-3 meters just in front of the antennas the electrical field levels were well below the international guidelines. (Author)

  10. Results from data gathered at the Rheinhausen measuring station in the year 1976

    International Nuclear Information System (INIS)

    Hoffmann, G.; Sauter, H.

    1978-11-01

    Construction, site and equipment of the Rheinhausen measuring station are described as far as they are meaningful for heat exchange and visibility research. Technical experiences are discussed. The sensible heat flux is found to be dependent mainly on air and water temperature, horizontal and vertical wind speed components, and wind direction. The dependencies are fitted by linear formulae. Measurements above the river yield better correlations than those above the bank. Furthermore there are statistical studies and interpretations of fog frequencies presented. The dependency on water-air temperature differences is discussed. The material represents the conditions above the Rhine surface which is almost not heated yet. Recommendations for continued measurements are given considering the so far results. (orig.) [de

  11. 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

  12. In situ measurement of electrostatic charge and charge distribution on flyash particles in power station exhaust stream

    Energy Technology Data Exchange (ETDEWEB)

    Guang, D.

    1992-01-01

    The electrostatic charges and charge distributions on individual flyash particles were experimentally measured in situ at four power stations in New South Wales and in the laboratory with an Electrostatic Charge Classifier. The global charge of these flyashes was also measured. The electrostatic charge on flyash particles of four power stations was found to be globally native. The median charge on the flyash particles varies linearly with particle diameter for all four flyashes. The electrostatic charge on the Tallawarra flyash particles was found to increase after passage through the air heater having huge metal surface areas, suggesting that triboelectrification was the primary charging mechanism for flyash particles. Distinctly different characteristics of the electrostatic charge, particle size and particle shape were found between the Eraring and the Tallawarra flyashes. The spherical Eraring ash has the highest proportion of lines and positively charged particles, but the lowest global charge level among the four flyashes. In contrast, the Tallawarra flyash has just the opposite. It is the distinct characteristics of the flyashes from Eraring and Tallawarra power stations that are responsible for the significant differences in their baghouse performance. The napping feature on the surface of the filter bags used in the Eraring and Tallawarra power stations provides an upstream surface of low fibre density above the fabric bulk. This feature presents and advantage to highly charged particles, like the Tallawarra flyash particles. Highly charged particles tend to deposit on such an upstream surface resulting in a porous dust cake with much less contact areas with the fabric medium than would otherwise be formed. This cake is easy to remove and provides less resistance to the gas flow. After singeing the naps on the filter bag surface at the Eraring power station, the problems of high pressure drop and retention of dust cake on the bas surface have been resolved.

  13. Turbulence characteristics of surface boundary layer over the Kalpakkam tropical coastal station, India

    Science.gov (United States)

    Prasad, K. B. R. R. Hari; Srinivas, C. V.; Singh, A. Bagavth; Naidu, C. V.; Baskaran, R.; Venkatraman, B.

    2018-05-01

    In this study turbulent fluxes and their intensity features are studied in different seasons at the tropical Indian coastal station, Kalpakkam. Measurements from Ultrasonic anemometer at 10 m agl over 30-day period of four seasons (winter 1-30 January; summer/spring 1-30 April; SW monsoon 1-30 July; NE monsoon 1-30 October) in 2013 and 2014 are used for this work. Various surface layer parameters viz, friction velocity (u *), Obukhov length (L), momentum flux (M), turbulent heat flux (H), turbulence kinetic energy (TKE) are computed using eddy correlation method. Results indicate that the study region is highly turbulent in summer followed by NE monsoon, winter and SW monsoon seasons. Derived parameters indicate that shear is the main contributing mechanism for TKE generation during SW monsoon and both shear and buoyancy contributed for the generation of TKE in other seasons. Site specific turbulent intensity relationships were developed by analyzing second order moments of 3D wind components as a function of stability parameter (z/L). The turbulent components of wind followed 1/3 power law in the unstable regime and - 1 power law in the stable regime. Comparisons with previous studies indicate that the turbulent intensity for horizontal winds at the coastal station is relatively less especially in the unstable conditions. The derived relationships are found to be unique and vary seasonally and suggest their application for improved modeling of atmospheric dispersion in the study domain. Rate of dissipation of TKE (ϕ ɛ) for stable and unstable conditions at the observation site is different from the earlier proposed relationships in the literature. Thus, a new relationship is proposed for the better fit of the data at this site.

  14. First observations of tropospheric δD data observed by ground- and space-based remote sensing and surface in-situ measurement techniques at MUSICA's principle reference station (Izaña Observatory, Spain)

    Science.gov (United States)

    González, Yenny; Schneider, Matthias; Christner, Emanuel; Rodríguez, Omaira E.; Sepúlveda, Eliezer; Dyroff, Christoph; Wiegele, Andreas

    2013-04-01

    The main goal of the project MUSICA (Multiplatform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water) is the generation of a quasi global tropospheric water vapor isototopologue dataset of a good and well-documented quality. Therefore, new ground- and space-based remote sensing observations (NDACC-FTIR and IASI/METOP) are combined with in-situ measurements. This work presents the first comparison between in-situ and remote sensing observations made at the Izaña Atmospheric Research Centre (Tenerife, Canary Islands, Spain). The in-situ measurements are made by a Picarro L2120-i water vapor isotopologue analyzer. At Izaña the in-situ data are affected by local small-scale mixing processes: during daylight, the thermally buoyant upslope flow prompts the mixing between the Marine Boundary Layer (MBL) and the low Free Troposphere (FT). However, the remote sensors detect δD values averaged over altitudes that are more representative for the free troposphere. This difference has to be considered for the comparison. In general, a good agreement between the MUSICA remote sensing and the in situ H2O-versus-δD plots is found, which demonstrates that the MUSICA δD remote sensing products add scientifically valuable information to the H2O data.

  15. Measuring market share of petrol stations using conditional probability approach

    Science.gov (United States)

    Sharif, Shamshuritawati; Lwee, Xue Yin

    2017-05-01

    Oil and gas production is the strength of Malaysia's growth over past decades. It is one of the most strategic economic branches in the world. Since the oil industry is essential for the economic growth of a country, only a few undertakings have been achieved to establish. It is a very risky business. Therefore the dealer must have some information in hand before setting up a new business plan. Understanding the current business situation is an important strategy to avoid risky ventures. In this study, the aim is to deliver a very simple but essential way to identify the market share based on customer's choice factors. This approach is presented to encourage the non-statisticians to use it easily in helping their business performance. From this study, the most important factors differ from one station to another station. The results show that the factors of customer's choice for BHPetrol, Caltex, PETRON, PETRONAS and SHELL are site location, service quality, service quality, size of the petrol station, and brand image, respectively.

  16. Daily snow depth measurements from 195 stations in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Allison, L.J. [ed.] [Oak Ridge National Lab., TN (United States). Carbon Dioxide Information Analysis Center; Easterling, D.R.; Jamason, P.; Bowman, D.P.; Hughes, P.Y.; Mason, E.H. [National Oceanic and Atmospheric Administration, Asheville, NC (United States). National Climatic Data Center

    1997-02-01

    This document describes a database containing daily measurements of snow depth at 195 National Weather Service (NWS) first-order climatological stations in the United States. The data have been assembled and made available by the National Climatic Data Center (NCDC) in Asheville, North Carolina. The 195 stations encompass 388 unique sampling locations in 48 of the 50 states; no observations from Delaware or Hawaii are included in the database. Station selection criteria emphasized the quality and length of station records while seeking to provide a network with good geographic coverage. Snow depth at the 388 locations was measured once per day on ground open to the sky. The daily snow depth is the total depth of the snow on the ground at measurement time. The time period covered by the database is 1893--1992; however, not all station records encompass the complete period. While a station record ideally should contain daily data for at least the seven winter months (January through April and October through December), not all stations have complete records. Each logical record in the snow depth database contains one station`s daily data values for a period of one month, including data source, measurement, and quality flags.

  17. The use of automatic weather stations to measure the soil temperature in the Mordovia State Nature Reserve (Russia in 2016

    Directory of Open Access Journals (Sweden)

    Oleg G. Grishutkin

    2017-10-01

    Full Text Available The article presents the soil temperature data obtained using two automatic weather stations located in the Mordovia State Nature Reserve (Russia. Measurements were carried out at the soil surface and at depths of 20 cm, 40 cm and 60 cm. The meteorological stations are located 15 km apart, in general, in similar landscapes. This caused similar results of meteorological measurements. Differences in the average of the daily temperature at corresponding depths are less than 2°C. The average annual temperature differs less than 0.5°C, i.е. within a sensor's error. The annual temperature trend is typical for Central Russia. And it is characterised by well warming in summer and stagnation in winter. The diurnal amplitudes are small. This can be explained by the location of both weather stations under the forest canopy and a well-developed ground vegetation cover.

  18. Measurements and modelling of base station power consumption under real traffic loads.

    Science.gov (United States)

    Lorincz, Josip; Garma, Tonko; Petrovic, Goran

    2012-01-01

    Base stations represent the main contributor to the energy consumption of a mobile cellular network. Since traffic load in mobile networks significantly varies during a working or weekend day, it is important to quantify the influence of these variations on the base station power consumption. Therefore, this paper investigates changes in the instantaneous power consumption of GSM (Global System for Mobile Communications) and UMTS (Universal Mobile Telecommunications System) base stations according to their respective traffic load. The real data in terms of the power consumption and traffic load have been obtained from continuous measurements performed on a fully operated base station site. Measurements show the existence of a direct relationship between base station traffic load and power consumption. According to this relationship, we develop a linear power consumption model for base stations of both technologies. This paper also gives an overview of the most important concepts which are being proposed to make cellular networks more energy-efficient.

  19. Measurements and Modelling of Base Station Power Consumption under Real Traffic Loads

    Directory of Open Access Journals (Sweden)

    Goran Petrovic

    2012-03-01

    Full Text Available Base stations represent the main contributor to the energy consumption of a mobile cellular network. Since traffic load in mobile networks significantly varies during a working or weekend day, it is important to quantify the influence of these variations on the base station power consumption. Therefore, this paper investigates changes in the instantaneous power consumption of GSM (Global System for Mobile Communications and UMTS (Universal Mobile Telecommunications System base stations according to their respective traffic load. The real data in terms of the power consumption and traffic load have been obtained from continuous measurements performed on a fully operated base station site. Measurements show the existence of a direct relationship between base station traffic load and power consumption. According to this relationship, we develop a linear power consumption model for base stations of both technologies. This paper also gives an overview of the most important concepts which are being proposed to make cellular networks more energy-efficient.

  20. Reassessment of urbanization effect on surface air temperature trends at an urban station of North China

    Science.gov (United States)

    Bian, Tao; Ren, Guoyu

    2017-11-01

    Based on a homogenized data set of monthly mean temperature, minimum temperature, and maximum temperature at Shijiazhuang City Meteorological Station (Shijiazhuang station) and four rural meteorological stations selected applying a more sophisticated methodology, we reanalyzed the urbanization effects on annual, seasonal, and monthly mean surface air temperature (SAT) trends for updated time period 1960-2012 at the typical urban station in North China. The results showed that (1) urbanization effects on the long-term trends of annual mean SAT, minimum SAT, and diurnal temperature range (DTR) in the last 53 years reached 0.25, 0.47, and - 0.50 °C/decade, respectively, all statistically significant at the 0.001 confidence level, with the contributions from urbanization effects to the overall long-term trends reaching 67.8, 78.6, and 100%, respectively; (2) the urbanization effects on the trends of seasonal mean SAT, minimum SAT, and DTR were also large and statistically highly significant. Except for November and December, the urbanization effects on monthly mean SAT, minimum SAT, and DTR were also all statistically significant at the 0.05 confidence level; and (3) the annual, seasonal, and monthly mean maximum SAT series at the urban station registered a generally weaker and non-significant urbanization effect. The updated analysis evidenced that our previous work for this same urban station had underestimated the urbanization effect and its contribution to the overall changes in the SAT series. Many similar urban stations were being included in the current national and regional SAT data sets, and the results of this paper further indicated the importance and urgency for paying more attention to the urbanization bias in the monitoring and detection of global and regional SAT change based on the data sets.

  1. Joint Inversion of Surface Waves Dispersion and Receiver Function at Cuba Seismic Stations

    International Nuclear Information System (INIS)

    Gonzalez, O'Leary; Moreno, Bladimir; Romanelli, Fabio; Panza, Giuliano F.

    2010-06-01

    Joint inversion of Rayleigh wave group velocity dispersion and receiver functions have been used to estimate the crust and upper mantle structure at eight seismic stations in Cuba. Receiver functions have been computed from teleseismic recordings of earthquakes at epicentral (angular) distances between 30 o and 90 o and Rayleigh wave group velocity dispersion have been taken from a surface-wave tomography study of the Caribbean area. The thickest crust (around 27 km) is found at Cascorro (CCC), Soroa (SOR), Moa (MOA) and Maisi (MAS) stations while the thinnest crust (around 18 km) is found at stations Rio Carpintero (RCC) and Guantanamo Bay (GTBY), in the southeastern of Cuba; this result is in agreement with the southward gradual thinning of the crust revealed by previous studies. The inversion shows a crystalline crust with S-wave velocity between 2.9 km/s and 3.9 km/s and at the crust-mantle transition zone the shear wave velocity varies from 3.9 km/s and 4.3 km/s. The lithospheric thickness varies from 74 km, in the youngest lithosphere, to 200 km in the middle of the Cuban island. Evidences of a subducted slab possibly belonging to the Caribbean plate are present below the stations Las Mercedes (LMG), RCC and GTBY and a thicker slab is present below the SOR station. (author)

  2. WIND SPEED AND ATMOSPHERIC STABILITY TRENDS FOR SELECTED UNITED STATES SURFACE STATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, R; Allen H. Weber, A

    2006-11-01

    Recently it has been suggested that global warming and a decrease in mean wind speeds over most land masses are related. Decreases in near surface wind speeds have been reported by previous investigators looking at records with time spans of 15 to 30 years. This study focuses on United States (US) surface stations that have little or no location change since the late 1940s or the 1950s--a time range of up to 58 years. Data were selected from 62 stations (24 of which had not changed location) and separated into ten groups for analysis. The group's annual averages of temperature, wind speed, and percentage of Pasquill-Gifford (PG) stability categories were fitted with linear least squares regression lines. The results showed that the temperatures have increased for eight of the ten groups as expected. Wind speeds have decreased for nine of the ten groups. The mean slope of the wind speed trend lines for stations within the coterminous US was -0.77 m s{sup -1} per century. The percentage frequency of occurrence for the neutral (D) PG stability category decreased, while that for the unstable (B) and the stable (F) categories increased in almost all cases except for the group of stations located in Alaska.

  3. Measurement of seismic moments at the RSTN station RSSD for NTS explosions

    International Nuclear Information System (INIS)

    Taylor, S.R.; Patton, H.J.

    1983-01-01

    We have estimated the seismic moment for two Nevada Test Site (NTS) explosions (Nebbiolo, 6/24/82; Atrisco, 8/5/82) at the Regional Seismic Test Network (RSTN) station in South Dakota (RSSD; distance from NTS approx. 1280 km). The moments are calculated from the vertical component mid-period channel for the Rayleigh waves and the merged mid- and short-period band for the P waves. The moment estimates from surface waves give values of 1.0 x 10 23 and 2.0 x 10 23 dyn-cm for Nebbiolo and Atrisco, respectively. The body-wave moments obtained at 0.5 Hz are approximately five times greater than those from surface waves and give values of 4.8 x 10 23 and 1.0 x 10 24 dyn-cm for Nebbiolo and Atrisco, respectively. The apparent discrepancy between the body and surface-wave moments can be resolved if there is overshoot (of 5:1) in the explosion source spectrum. As a check on the absolute value of the surface-wave moments, we compared them to moment values predicted from empirical moment-yield relationships for different emplacement media at NTS (Patton, 1983). We found that the agreement between observed and predicted values is satisfactory, within the measurement error on the moments at the one sigma level

  4. Core power distribution measurement and data processing in Daya Bay Nuclear Power Station

    International Nuclear Information System (INIS)

    Zhang Hong

    1997-01-01

    For the first time in China, Daya Bay Nuclear Power Station applied the advanced technology of worldwide commercial pressurized reactors to the in-core detectors, the leading excore six-chamber instrumentation for precise axial power distribution, and the related data processing. Described in this article are the neutron flux measurement in Daya Bay Nuclear Power Station, and the detailed data processing

  5. Project authorization process in the thermal power stations vs in the hydroelectric power stations: two weights, two measurements?

    International Nuclear Information System (INIS)

    Comtois, Y.

    2004-01-01

    Key topics include the long tendering process, a comparison of two projects: thermal station vs. hydroelectrical station, and the solutions towards reducing the delay in obtaining authorization. (author)

  6. The Rover Environmental Monitoring Station Ground Temperature Sensor: A Pyrometer for Measuring Ground Temperature on Mars

    Directory of Open Access Journals (Sweden)

    Miguel Ramos

    2010-10-01

    Full Text Available We describe the parameters that drive the design and modeling of the Rover Environmental Monitoring Station (REMS Ground Temperature Sensor (GTS, an instrument aboard NASA’s Mars Science Laboratory, and report preliminary test results. REMS GTS is a lightweight, low-power, and low cost pyrometer for measuring the Martian surface kinematic temperature. The sensor’s main feature is its innovative design, based on a simple mechanical structure with no moving parts. It includes an in-flight calibration system that permits sensor recalibration when sensor sensitivity has been degraded by deposition of dust over the optics. This paper provides the first results of a GTS engineering model working in a Martian-like, extreme environment.

  7. Station-keeping control of an unmanned surface vehicle exposed to current and wind disturbances

    OpenAIRE

    Sarda, Edoardo I.; Qu, Huajin; Bertaska, Ivan R.; von Ellenrieder, Karl D.

    2017-01-01

    Field trials of a 4 meter long, 180 kilogram, unmanned surface vehicle (USV) have been conducted to evaluate the performance of station-keeping heading and position controllers in an outdoor marine environment disturbed by wind and current. The USV has a twin hull configuration and a custom-designed propulsion system, which consists of two azimuthing thrusters, one for each hull. Nonlinear proportional derivative, backstepping and sliding mode feedback controllers were tested in winds of abou...

  8. Measurement station for interim inspections of Lightbridge metallic fuel rods at the Halden Boiling Water Reactor

    Science.gov (United States)

    Hartmann, C.; Totemeier, A.; Holcombe, S.; Liverud, J.; Limi, M.; Hansen, J. E.; Navestad, E. AB(; )

    2018-01-01

    Lightbridge Corporation has developed a new Uranium-Zirconium based metallic fuel. The fuel rods aremanufactured via a co-extrusion process, and are characterized by their multi-lobed (cruciform-shaped) cross section. The fuel rods are also helically-twisted in the axial direction. Two experimental fuel assemblies, each containing four Lightbridge fuel rods, are scheduled to be irradiated in the Halden Boiling Water Reactor (HBWR) starting in 2018. In addition to on-line monitoring of fuel rod elongation and critical assembly conditions (e.g. power, flow rates, coolant temperatures, etc.) during the irradiation, several key parameters of the fuel will be measured out-of-core during interim inspections. An inspection measurement station for use in the irradiated fuel handling compartment at the HBWR has therefore been developed for this purpose. The multi-lobed cladding cross section combined with the spiral shape of the Lightbridge metallic fuel rods requires a high-precision guiding system to ensure good position repeatability combined with low-friction guiding. The measurement station is equipped with a combination of instruments and equipment supplied from third-party vendors and instruments and equipment developed at Institute for Energy Technology (IFE). Two sets of floating linear voltage differential transformer (LVDT) pairs are used to measure swelling and diameter changes between the lobes and the valleys over the length of the fuel rods. Eddy current probes are used to measure the thickness of oxide layers in the valleys and on the lobe tips and also to detect possible surface cracks/pores. The measurement station also accommodates gamma scans. Additionally, an eddy-current probe has been developed at IFE specifically to detect potential gaps or discontinuities in the bonding layer between the metallic fuel and the Zirconium alloy cladding. Potential gaps in the bonding layer will be hidden behind a 0.5-1.0 mm thick cladding wall. It has therefore been

  9. Measuring the Amount of Eroded Soil and Surface Runoff Water in the Field

    OpenAIRE

    Abdulfatah Faraj Aboufayed

    2013-01-01

    Water erosion is the most important problems of the soil in the Jabel Nefusa area located in northwest of Libya; therefore, erosion station had been established in the Faculty of Veterinary and dryfarming research Station, University of the Al-japel Al-gharbi in Zentan. The length of the station is 72.6 feet, 6 feet width and the percentage of its slope is 3%. The station were established to measure the amount of soil eroded and amount of surface water produced during the seasons 95/96 and 96...

  10. 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....

  11. Air pollution assessment in the Slovak Republic in 2005. Measurement stations of air quality monitoring network

    International Nuclear Information System (INIS)

    Anon

    2006-05-01

    In this Appendix to the report 'Air pollution assessment in the Slovak Republic in 2005' the main characteristics of measurement stations of air quality monitoring network of the Slovak Republic are presented

  12. Air pollution assessment in the Slovak Republic in 2004. Measurement stations of air quality monitoring network

    International Nuclear Information System (INIS)

    Anon

    2005-07-01

    In this Appendix to the report 'Air pollution assessment in the Slovak Republic in 2004' the main characteristics of measurement stations of air quality monitoring network of the Slovak Republic are presented

  13. Radiation Measurement from Mobile Base Stations at a University Campus in Malaysia

    OpenAIRE

    Md. R. Islam; Othman O. Khalifa; Liakot Ali; Amir Azli; Mohd Zulkarnain

    2006-01-01

    The tremendous growth of telecommunication industry results the number of hand phone users increases everyday. In order to support the growing number of users, the mobile base stations can be seen in almost everywhere. This scenario has created uncomfortable feelings to the people that they may be affected by the radiations from antennas. A measurement was done at student hostels and office premises near to base stations in International Islamic University Malaysia, Gombak campus. Measured va...

  14. Reliability of Various Measurement Stations for Determining Plantar Fascia Thickness and Echogenicity

    Directory of Open Access Journals (Sweden)

    Adebisi Bisi-Balogun

    2016-04-01

    Full Text Available This study aimed to determine the relative and absolute reliability of ultrasound (US measurements of the thickness and echogenicity of the plantar fascia (PF at different measurement stations along its length using a standardized protocol. Twelve healthy subjects (24 feet were enrolled. The PF was imaged in the longitudinal plane. Subjects were assessed twice to evaluate the intra-rater reliability. A quantitative evaluation of the thickness and echogenicity of the plantar fascia was performed using Image J, a digital image analysis and viewer software. A sonography evaluation of the thickness and echogenicity of the PF showed a high relative reliability with an Intra class correlation coefficient of ≥0.88 at all measurement stations. However, the measurement stations for both the PF thickness and echogenicity which showed the highest intraclass correlation coefficient (ICCs did not have the highest absolute reliability. Compared to other measurement stations, measuring the PF thickness at 3 cm distal and the echogenicity at a region of interest 1 cm to 2 cm distal from its insertion at the medial calcaneal tubercle showed the highest absolute reliability with the least systematic bias and random error. Also, the reliability was higher using a mean of three measurements compared to one measurement. To reduce discrepancies in the interpretation of the thickness and echogenicity measurements of the PF, the absolute reliability of the different measurement stations should be considered in clinical practice and research rather than the relative reliability with the ICC.

  15. Reliability of Various Measurement Stations for Determining Plantar Fascia Thickness and Echogenicity.

    Science.gov (United States)

    Bisi-Balogun, Adebisi; Cassel, Michael; Mayer, Frank

    2016-04-13

    This study aimed to determine the relative and absolute reliability of ultrasound (US) measurements of the thickness and echogenicity of the plantar fascia (PF) at different measurement stations along its length using a standardized protocol. Twelve healthy subjects (24 feet) were enrolled. The PF was imaged in the longitudinal plane. Subjects were assessed twice to evaluate the intra-rater reliability. A quantitative evaluation of the thickness and echogenicity of the plantar fascia was performed using Image J, a digital image analysis and viewer software. A sonography evaluation of the thickness and echogenicity of the PF showed a high relative reliability with an Intra class correlation coefficient of ≥0.88 at all measurement stations. However, the measurement stations for both the PF thickness and echogenicity which showed the highest intraclass correlation coefficient (ICCs) did not have the highest absolute reliability. Compared to other measurement stations, measuring the PF thickness at 3 cm distal and the echogenicity at a region of interest 1 cm to 2 cm distal from its insertion at the medial calcaneal tubercle showed the highest absolute reliability with the least systematic bias and random error. Also, the reliability was higher using a mean of three measurements compared to one measurement. To reduce discrepancies in the interpretation of the thickness and echogenicity measurements of the PF, the absolute reliability of the different measurement stations should be considered in clinical practice and research rather than the relative reliability with the ICC.

  16. Aspheric surface measurement using capacitive probes

    Science.gov (United States)

    Tao, Xin; Yuan, Daocheng; Li, Shaobo

    2017-02-01

    With the application of aspheres in optical fields, high precision and high efficiency aspheric surface metrology becomes a hot research topic. We describe a novel method of non-contact measurement of aspheric surface with capacitive probe. Taking an eccentric spherical surface as the object of study, the averaging effect of capacitive probe measurement and the influence of tilting the capacitive probe on the measurement results are investigated. By comparing measurement results from simultaneous measurement of the capacitive probe and contact probe of roundness instrument, this paper indicates the feasibility of using capacitive probes to test aspheric surface and proposes the compensation method of measurement error caused by averaging effect and the tilting of the capacitive probe.

  17. Measurements of MIMO Indoor Channels at 1800 MHz with Multiple Indoor and Outdoor Base Stations

    Directory of Open Access Journals (Sweden)

    Jaldén Niklas

    2007-01-01

    Full Text Available This paper proposes several configurations for multiple base stations in indoor MIMO systems and compares their performance. The results are based on channel measurements realized with a MIMO testbed. The receiver was moved along several routes and floors on an office building. Both outdoor and indoor locations are considered for the transmitters or base stations, which allow the analysis of not only indoor but also outdoor-to-indoor environment. The use of 2 base stations with different system level combinations of the two is analyzed. We show that the configuration with base station selection provides almost as good performance as a full water-filling scheme when the 2 base stations are placed at different locations. Also the spatial correlation properties for the different configurations are analyzed and the importance of considering path loss when evaluating capacity is highlighted.

  18. 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.

  19. Radiochemical analyses of surface water from U.S. Geological Survey hydrologic bench-mark stations

    Science.gov (United States)

    Janzer, V.J.; Saindon, L.G.

    1972-01-01

    The U.S. Geological Survey's program for collecting and analyzing surface-water samples for radiochemical constituents at hydrologic bench-mark stations is described. Analytical methods used during the study are described briefly and data obtained from 55 of the network stations in the United States during the period from 1967 to 1971 are given in tabular form.Concentration values are reported for dissolved uranium, radium, gross alpha and gross beta radioactivity. Values are also given for suspended gross alpha radioactivity in terms of natural uranium. Suspended gross beta radioactivity is expressed both as the equilibrium mixture of strontium-90/yttrium-90 and as cesium-137.Other physical parameters reported which describe the samples include the concentrations of dissolved and suspended solids, the water temperature and stream discharge at the time of the sample collection.

  20. Study on the three-station typical network deployments of workspace Measurement and Positioning System

    Science.gov (United States)

    Xiong, Zhi; Zhu, J. G.; Xue, B.; Ye, Sh. H.; Xiong, Y.

    2013-10-01

    As a novel network coordinate measurement system based on multi-directional positioning, workspace Measurement and Positioning System (wMPS) has outstanding advantages of good parallelism, wide measurement range and high measurement accuracy, which makes it to be the research hotspots and important development direction in the field of large-scale measurement. Since station deployment has a significant impact on the measurement range and accuracy, and also restricts the use-cost, the optimization method of station deployment was researched in this paper. Firstly, positioning error model was established. Then focusing on the small network consisted of three stations, the typical deployments and error distribution characteristics were studied. Finally, through measuring the simulated fuselage using typical deployments at the industrial spot and comparing the results with Laser Tracker, some conclusions are obtained. The comparison results show that under existing prototype conditions, I_3 typical deployment of which three stations are distributed in a straight line has an average error of 0.30 mm and the maximum error is 0.50 mm in the range of 12 m. Meanwhile, C_3 typical deployment of which three stations are uniformly distributed in the half-circumference of an circle has an average error of 0.17 mm and the maximum error is 0.28 mm. Obviously, C_3 typical deployment has a higher control effect on precision than I_3 type. The research work provides effective theoretical support for global measurement network optimization in the future work.

  1. Surface texture measurement for additive manufacturing

    Science.gov (United States)

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

    2015-06-01

    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.

  2. 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)

  3. Over 600 mobile base station measurements in Buenos Aires City, how far are general public limits?

    International Nuclear Information System (INIS)

    Aguirre, Anibal; Dalmas Di Giovanni, Norberto; Garcia Diaz, Javier; Douthat, Analia; Munoz, Claudio; Saint Nom, Roxana

    2008-01-01

    Full text: The general public worries about non ionizing radiation (NIR), produced by mobile base station aren't new, mainly in big cities like Buenos Aires where the amount of antennas of wide communication services (mobile, data links, FM Broadcasting, TV and others), are so considerable. Buenos Aires City has 3 million inhabitants in a surface of 203 km 2 and has about 700 mobile base stations between macro and micro cells. When public demand arrived to local government authorities, the first logical step was to promote a big measurement campaign to do a radiation map of the city. This measurement campaign has been done for two measurement teams, one with CITEFA NIR specialists and the other with ITBA NIR specialists, during 6 months. Local NRI measurement guidelines established that has to be taken between 12 and 16 points around NRI source in a 50 m or 100 m radius, depending on the neighbourhood buildings features (buildings located in the centre of the city aren't the same as a quiet house district). The obtained measured values had to be compared with Argentinean exposure limits, which are the same that ICNIRP limits. With over 7500 measured points in the entire city with wide band instruments (200 kHz-40 GHz), we have started our analysis. This information has been used by local authorities to upgrade a radiation map that can be consulted on the local government internet site. We have compared the obtained values with some international general public exposure limits. From this comparison we found that over 90% of measured points were under general public ICNIRP cell phone frequency limits, but the surprise was that, about 80% of them were below Russian limits (6 V/m) that are the strictest of the world. According to the obtained results and to provide a conclusion we could say that, if in a big city with a very high NIR sources density, we find a majority of lower limits values, this situation will be better in a little town with few NIR sources. However

  4. Measuring Light Reflectance of BGO Crystal Surfaces

    Science.gov (United States)

    Janecek, Martin; Moses, William W.

    2008-10-01

    A scintillating crystal's surface reflectance has to be well understood in order to accurately predict and optimize the crystal's light collection through Monte Carlo simulations. In this paper, we measure the inner surface reflectance properties for BGO. The measurements include BGO crystals with a mechanically polished surface, rough-cut surface, and chemically etched surface, and with various reflectors attached, both air-coupled and with coupling compound. The measurements are performed with a laser aimed at the center of a hemispherical shaped BGO crystal. The hemispherical shape eliminates any non-perpendicular angles for light entering and exiting the crystal. The reflected light is collected with an array of photodiodes. The laser can be set at an arbitrary angle, and the photodiode array is rotated to fully cover 2pi of solid angle. The current produced in the photodiodes is readout with a digital multimeter connected through a multiplexer. The two rows of photodiodes achieve 5-degree by 4-degree resolution, and the current measurement has a dynamic range of 105:1. The acquired data was not described by the commonly assumed linear combination of specular and diffuse (Lambertian) distributions, except for a very few surfaces. Surface roughness proved to be the most important parameter when choosing crystal setup. The reflector choice was of less importance and of almost no consequence for rough-cut surfaces. Pure specular reflection distribution for all incidence angles was measured for polished surfaces with VM2000 film, while the most Lambertian distribution for any surface finish was measured for titanium dioxide paint. The distributions acquired in this paper will be used to create more accurate Monte Carlo models for light reflection distribution within BGO crystals.

  5. Data Collected in 1959 by English Research Vessels at Serial and Surface Hydrographic Stations (NODC Accession 6900852)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The present volume contains data collected in 1959 by English research vessels at serial and surface hydrographic stations. The data list are preceded by a number of...

  6. Geometric Measure Theory and Minimal Surfaces

    CERN Document Server

    Bombieri, Enrico

    2011-01-01

    W.K. ALLARD: On the first variation of area and generalized mean curvature.- F.J. ALMGREN Jr.: Geometric measure theory and elliptic variational problems.- E. GIUSTI: Minimal surfaces with obstacles.- J. GUCKENHEIMER: Singularities in soap-bubble-like and soap-film-like surfaces.- D. KINDERLEHRER: The analyticity of the coincidence set in variational inequalities.- M. MIRANDA: Boundaries of Caciopoli sets in the calculus of variations.- L. PICCININI: De Giorgi's measure and thin obstacles.

  7. A Probabilistic Model to Evaluate the Optimal Density of Stations Measuring Snowfall.

    Science.gov (United States)

    Schneebeli, Martin; Laternser, Martin

    2004-05-01

    Daily new snow measurements are very important for avalanche forecasting and tourism. A dense network of manual or automatic stations measuring snowfall is necessary to have spatially reliable data. Snow stations in Switzerland were built at partially subjective locations. A probabilistic model based on the frequency and spatial extent of areas covered by heavy snowfalls was developed to quantify the probability that snowfall events are measured by the stations. Area probability relations were calculated for different thresholds of daily accumulated snowfall. A probabilistic model, including autocorrelation, was used to calculate the optimal spacing of stations based on simulated triangular grids and to compare the capture probability of different networks and snowfall thresholds. The Swiss operational snow-stations network captured snowfall events with high probability, but the distribution of the stations could be optimized. The spatial variability increased with higher thresholds of daily accumulated snowfall, and the capture probability decreased with increasing thresholds. The method can be used for other areas where the area probability relation for threshold values of snow or rain can be calculated.

  8. Current situation and control measures of groundwater pollution in gas station

    Science.gov (United States)

    Wu, Qiong; Zhang, Xiaofeng; Zhang, Qianjin

    2017-11-01

    In recent years, pollution accidents caused by gas station leakage has occurred worldwide which can be persistent in groundwater. Numerous studies have demonstrated that the contaminated groundwater is threatening the ecological environment and human health. In this article, current status and sources of groundwater pollution by gas station are analyzed, and experience of how to prevent groundwater pollution from gas stations are summarized. It is demonstrated that installation of secondary containment measures for the oil storage of the oil tank system, such as installation of double-layer oil tanks or construction of impermeable ponds, is a preferable method to prevent gas stations from groundwater pollution. Regarding to the problems of groundwater pollution caused by gas station, it is proposed that it is urgent to investigate the leakage status of gas station. Relevant precise implementation regulations shall be issued and carried out, and supervision management of gas stations would need to be strengthened. Then single-layer steel oil tanks shall be replaced by double-layer tanks, and the impermeable ponds should be constructed according to the risk ranking. From the control methodology, the groundwater environment monitoring systems, supervision level, laws and regulations as well as pollution remediation should also be carried out and strengthened.

  9. A Novel RFID Sensing System Using Enhanced Surface Wave Technology for Battery Exchange Stations

    Directory of Open Access Journals (Sweden)

    Yeong-Lin Lai

    2014-01-01

    Full Text Available This paper presents a novel radio-frequency identification (RFID sensing system using enhanced surface wave technology for battery exchange stations (BESs of electric motorcycles. Ultrahigh-frequency (UHF RFID technology is utilized to automatically track and manage battery and user information without manual operation. The system includes readers, enhanced surface wave leaky cable antennas (ESWLCAs, coupling cable lines (CCLs, and small radiation patches (SRPs. The RFID sensing system overcomes the electromagnetic interference in the metallic environment of a BES cabinet. The developed RFID sensing system can effectively increase the efficiency of BES operation and promote the development of electric vehicles which solve the problem of air pollution as well as protect the environment of the Earth.

  10. Sound field separation with cross measurement surfaces.

    Directory of Open Access Journals (Sweden)

    Jin Mao

    Full Text Available With conventional near-field acoustical holography, it is impossible to identify sound pressure when the coherent sound sources are located on the same side of the array. This paper proposes a solution, using cross measurement surfaces to separate the sources based on the equivalent source method. Each equivalent source surface is built in the center of the corresponding original source with a spherical surface. According to the different transfer matrices between equivalent sources and points on holographic surfaces, the weighting of each equivalent source from coherent sources can be obtained. Numerical and experimental studies have been performed to test the method. For the sound pressure including noise after separation in the experiment, the calculation accuracy can be improved by reconstructing the pressure with Tikhonov regularization and the L-curve method. On the whole, a single source can be effectively separated from coherent sources using cross measurement.

  11. Magnetostrictive device for high-temperature sound and vibration measurement in nuclear power stations

    International Nuclear Information System (INIS)

    Hans, R.; Podgorski, J.

    1977-01-01

    The demands on the monitoring systems in nuclear power stations are increasing continuously, not only because of more stringent safety requirements but also for reasons of plant availability and thus economic efficiency. The noise and vibration measurements which therefore have to be taken make it necessary to provide measuring devices with a high degree of efficiency, adequate sensitivity and resistance to high temperatures, radiation and corrosion. Probes using the magnetostrictive effect, whereby a ferromagnetic core changes its length in a magnetic field - a phenomenon which has been known for approximately fifty years - fulfill all the conditions for application in nuclear power stations. (orig.) [de

  12. Total gamma activity measurements for determining the radioactivity of residual materials from nuclear power stations

    International Nuclear Information System (INIS)

    Auler, I.; Meyer, M.; Stickelmann, J.

    1995-01-01

    Large amounts of residual materials from retrofitting measures and from decommissioning of nuclear power stations shows such a weak level of radioactivity that they could be released after decision measurements. Expenses incurred with complex geometry cannot be taken with common methods. NIS developed a Release Measurement Facility (RMF) based on total gamma activity measurements especially for these kind of residual materials. The RMF has been applied for decision measurements in different nuclear power plants. Altogether about 2,000 Mg of various types of materials have been measured up to now. More than 90 % of these materials could be released 0 without any restriction after decision measurements

  13. 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

  14. Different Multifractal Scaling of the 0 cm Average Ground Surface Temperature of Four Representative Weather Stations over China

    Directory of Open Access Journals (Sweden)

    Lei Jiang

    2013-01-01

    Full Text Available The temporal scaling properties of the daily 0 cm average ground surface temperature (AGST records obtained from four selected sites over China are investigated using multifractal detrended fluctuation analysis (MF-DFA method. Results show that the AGST records at all four locations exhibit strong persistence features and different scaling behaviors. The differences of the generalized Hurst exponents are very different for the AGST series of each site reflecting the different scaling behaviors of the fluctuation. Furthermore, the strengths of multifractal spectrum are different for different weather stations and indicate that the multifractal behaviors vary from station to station over China.

  15. 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…

  16. 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...

  17. 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.

  18. Spectrum of the cosmic background radiation: early and recent measurements from the White Mountain Research Station

    International Nuclear Information System (INIS)

    Smoot, G.F.

    1985-09-01

    The White Mountain Research Station has provided a support facility at a high, dry, radio-quiet site for measurements that have established the blackbody character of the cosmic microwave background radiation. This finding has confirmed the interpretation of the radiation as a relic of the primeval fireball and helped to establish the hot Big Bang theory as the standard cosmological model

  19. Infrared and UV-visible absorption measurement at Syowa Station (abstract)

    OpenAIRE

    Murata,Isao; Kita,Kazuyuki; Iwagami,Naomoto; Ogawa ,Toshihiro

    1993-01-01

    Vertical column contents of some trace gases were observed by solar infrared and UV-visible absorption techniques at Syowa Station, to study the dynamics and chemistry of Antarctic ozone. HCl, HF, N_2O, OCS, CO and C_2H_6 column contents were measured by infrared absorption spectroscopy in the 3-5

  20. Tethered balloon operation for wintering aerosol measurements in the lower troposphere at Syowa Station, Antarctica

    OpenAIRE

    Keiichiro Hara; Kazuo Osada; Takashi Yamanouchi

    2007-01-01

    The 46th Japanese Antarctic Research Expedition (JARE-46) carried out twenty seven tethered-balloon-borne aerosol measurements at Syowa Station for better understanding of aerosol chemical and physical properties in the lower troposphere from 6th January 2005 until 11 December 2005. This report summarizes the plan, preparation, field activities and some troubles/problems in the tethered-balloon observations.

  1. Simulating air temperature in an urban street canyon in all weather conditions using measured data at a reference meteorological station

    Science.gov (United States)

    Erell, E.; Williamson, T.

    2006-10-01

    A model is proposed that adapts data from a standard meteorological station to provide realistic site-specific air temperature in a city street exposed to the same meso-scale environment. In addition to a rudimentary description of the two sites, the canyon air temperature (CAT) model requires only inputs measured at standard weather stations; yet it is capable of accurately predicting the evolution of air temperature in all weather conditions for extended periods. It simulates the effect of urban geometry on radiant exchange; the effect of moisture availability on latent heat flux; energy stored in the ground and in building surfaces; air flow in the street based on wind above roof height; and the sensible heat flux from individual surfaces and from the street canyon as a whole. The CAT model has been tested on field data measured in a monitoring program carried out in Adelaide, Australia, in 2000-2001. After calibrating the model, predicted air temperature correlated well with measured data in all weather conditions over extended periods. The experimental validation provides additional evidence in support of a number of parameterisation schemes incorporated in the model to account for sensible heat and storage flux.

  2. Validation of OMI UV measurements against ground-based measurements at a station in Kampala, Uganda

    Science.gov (United States)

    Muyimbwa, Dennis; Dahlback, Arne; Stamnes, Jakob; Hamre, Børge; Frette, Øyvind; Ssenyonga, Taddeo; Chen, Yi-Chun

    2015-04-01

    We present solar ultraviolet (UV) irradiance data measured with a NILU-UV instrument at a ground site in Kampala (0.31°N, 32.58°E), Uganda for the period 2005-2014. The data were analyzed and compared with UV irradiances inferred from the Ozone Monitoring Instrument (OMI) for the same period. Kampala is located on the shores of lake Victoria, Africa's largest fresh water lake, which may influence the climate and weather conditions of the region. Also, there is an excessive use of worn cars, which may contribute to a high anthropogenic loading of absorbing aerosols. The OMI surface UV algorithm does not account for absorbing aerosols, which may lead to systematic overestimation of surface UV irradiances inferred from OMI satellite data. We retrieved UV index values from OMI UV irradiances and validated them against the ground-based UV index values obtained from NILU-UV measurements. The UV index values were found to follow a seasonal pattern similar to that of the clouds and the rainfall. OMI inferred UV index values were overestimated with a mean bias of about 28% under all-sky conditions, but the mean bias was reduced to about 8% under clear-sky conditions when only days with radiation modification factor (RMF) greater than 65% were considered. However, when days with RMF greater than 70, 75, and 80% were considered, OMI inferred UV index values were found to agree with the ground-based UV index values to within 5, 3, and 1%, respectively. In the validation we identified clouds/aerosols, which were present in 88% of the measurements, as the main cause of OMI inferred overestimation of the UV index.

  3. 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)

  4. Measurements of RF Radiation in the Vicinity of FM and TV Broadcasting Stations

    Directory of Open Access Journals (Sweden)

    Abdulaziz S. Al-Ruwais

    2001-12-01

    Full Text Available This paper provides measurements of power density around an FM and VHF-TV broadcasting station and its variation with distance.  The maximum measured value was about 2.4 mW/cm2 at a height of 2 meters above ground level while the average value was fluctuating around 1 mW/cm2.  It was found that the measured power density increases with height above ground and it reaches about 3.5 mW/cm2 at a height of about 15 meters at a location of about 400 meters from the station.  At a nearer distance of 185 meters from the tower another measurement was taken at a height of 18 meters, the power density increased to 41 mW/cm2.

  5. Survey of radiofrequency radiation levels around GSM base stations and evaluation of measurement uncertainty

    Directory of Open Access Journals (Sweden)

    Vulević Branislav D.

    2011-01-01

    Full Text Available This paper is a summary of broadband measurement values of radiofrequency radiation around GSM base stations in the vicinity of residential areas in Belgrade and 12 other cities in Serbia. It will be useful for determining non-ionizing radiation exposure levels of the general public in the future. The purpose of this paper is also an appropriate representation of basic information on the evaluation of measurement uncertainty.

  6. Selection of the reference concept for the surface examination stations in the fuels and materials examination facility

    International Nuclear Information System (INIS)

    Frandsen, G.B.; Nash, C.R.

    1978-01-01

    The prototype surface examination station for the Fuels and Materials Examination Facility (FMEF) will use closed circuit television (CCTV) for routine modes of operation along with a nuclear periscope for special examination needs. The CCTV and the nuclear periscope were evaluated against prescribed station requirements and compared in a side-by-side demonstration. A quantitative evaluation of their outputs showed that both systems were capable of meeting surface anomaly detection requirements. The CCTV system was superior in its ability to collect, suppress and present data into a more useful form for the experimenters

  7. 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.

  8. Surface aerosol measurements at Barrow during AGASP

    International Nuclear Information System (INIS)

    Bodhaine, B.A.; Dutton, E.G.; DeLuisi, J.J.

    1984-01-01

    Surface aerosol measurements were made at the Barrow GMCC Observatory during the AGASP flight series in March 1983. The condensation nucleus, scattering extinction coefficient, size distribution, and total aerosol optical depth measurements all clearly show conditions of background Arctic haze for March 9-11, a series of haze episodes during March 12-16, and a return to background haze for March 17-18. Angstrom exponents calculated from scattering coefficient data were low during March 9-11, relatively higher during March 12-14, and highest during March 15-18. Surface aerosol data and aerosol optical depth data are in good qualitative agreement for the 10-day period studied. Background haze was present when trajectories circled the Arctic basin, and haze episodes occurred when trajectories originated in western Asia and Europe

  9. Plasma measurements with surface barrier detectors

    International Nuclear Information System (INIS)

    Futch, A.H. Jr.; Bradley, A.E.

    1969-01-01

    A surface barrier detector system for measuring the loss rate of protons from a hydrogen plasma and their energy spectrum is described. A full width at half maximum (FWHM) resolution of 1.4 keV for 15-keV hydrogen atoms was obtained using a selected detector having a sensitive area of 3 mm 2 and a depletion depth of 700 microns

  10. 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

  11. 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.)

  12. Study of sources, dose contribution and control measures of Argon-41 at Kaiga Generating Station

    International Nuclear Information System (INIS)

    Venkata Ramana, K.; Shrikrishna, U.V.; Manojkumar, M.; Ramesh, R.; Madhan, V.; Varadhan, R.S.

    2001-01-01

    Air is used as a medium for cooling calandria vault and thermal shield systems in the earlier Pressurised Heavy Water Reactors (Rajasthan Atomic Power Station and Madras Atomic Power Station) in India. This leads to production of significant quantity of 41 Ar in calandria vault and thermal shield cooling systems due to neutron activation of 40 Ar present in air (∼1% v/v). The presence of 41 Ar in reactor building contributes significant external doses to plant personnel during reactor operation and the release of this radionuclide to the environment result in dose to the public in the vicinity of the plants. An attempt is made to eliminate Argon-41 production in Indian standard Pressurised Heavy Water Reactors (Narora Atomic Power Station, Kakrapar Atomic Power Station, Kaiga Generating Station -1 and 2 and Rajasthan Atomic Power Station-3 and 4), by filling the calandria vault with demineralized water and providing a separate Annulus Gas Monitoring System (AGMS) for detecting leaks from calandria tube or pressure tube using Carbon dioxide as a medium. However, 41 Ar is produced in the Annulus Gas Monitoring System, Primary Heat Transport cover gas system and moderator cover gas system due to ingress of air into the systems during operational transients or due to trace quantity of air present as an impurity in the gases used for the above systems. A study was conducted to identify and quantify the sources of 41 Ar in the work areas. This report brings out the sources of 41 Ar, reasons for 41 Ar production and the results of the measures incorporated to reduce the presence of 41 Ar in the above systems. (author)

  13. Doping profile measurement on textured silicon surface

    Science.gov (United States)

    Essa, Zahi; Taleb, Nadjib; Sermage, Bernard; Broussillou, Cédric; Bazer-Bachi, Barbara; Quillec, Maurice

    2018-04-01

    In crystalline silicon solar cells, the front surface is textured in order to lower the reflection of the incident light and increase the efficiency of the cell. This texturing whose dimensions are a few micrometers wide and high, often makes it difficult to determine the doping profile measurement. We have measured by secondary ion mass spectrometry (SIMS) and electrochemical capacitance voltage profiling the doping profile of implanted phosphorus in alkaline textured and in polished monocrystalline silicon wafers. The paper shows that SIMS gives accurate results provided the primary ion impact angle is small enough. Moreover, the comparison between these two techniques gives an estimation of the concentration of electrically inactive phosphorus atoms.

  14. Highly accurate surface maps from profilometer measurements

    Science.gov (United States)

    Medicus, Kate M.; Nelson, Jessica D.; Mandina, Mike P.

    2013-04-01

    Many aspheres and free-form optical surfaces are measured using a single line trace profilometer which is limiting because accurate 3D corrections are not possible with the single trace. We show a method to produce an accurate fully 2.5D surface height map when measuring a surface with a profilometer using only 6 traces and without expensive hardware. The 6 traces are taken at varying angular positions of the lens, rotating the part between each trace. The output height map contains low form error only, the first 36 Zernikes. The accuracy of the height map is ±10% of the actual Zernike values and within ±3% of the actual peak to valley number. The calculated Zernike values are affected by errors in the angular positioning, by the centering of the lens, and to a small effect, choices made in the processing algorithm. We have found that the angular positioning of the part should be better than 1?, which is achievable with typical hardware. The centering of the lens is essential to achieving accurate measurements. The part must be centered to within 0.5% of the diameter to achieve accurate results. This value is achievable with care, with an indicator, but the part must be edged to a clean diameter.

  15. Intercomparison study of atmospheric methane and carbon dioxide concentrations measured at the Ebre River Delta Station

    Science.gov (United States)

    Occhipinti, Paola; Morguí, Josep Anton; Àgueda, Alba; Batet, Oscar; Borràs, Sílvia; Cañas, Lídia; Curcoll, Roger; Grossi, Claudia; Nofuentes, Manel; Vazquez, Eusebi; Rodó, Xavier

    2015-04-01

    In the framework of the ClimaDat project, IC3 has established a network of eight monitoring stations across the Iberian Peninsula and the Canarian Archipelago with the aim of studying climate processes. The monitoring station at the Ebre River Delta (DEC3) is located in the Ebre River Delta Natural Park (40° 44' N; 0° 47' E) and it is characterized by the typical North-Western Mediterranean climate. Since 2013, atmospheric greenhouse gases (GHG) and 222Rn tracer gas together with the meteorological parameters are continuously measured from a 10 m a.g.l. height tower. Atmospheric GHG (CO2, CH4, CO and N2O) concentrations are determined using a Picarro analyzer G2301 (CO2 and CH4) and a modified gas chromatograph (GC) Agilent 6890N (CO2, CH4, CO and N2O). Open data access is available from the www.climadat.es website. Data collected at the DEC3 station are also submitted to the InGOS platform since this station is part of the InGOS European infrastructure project. Researchers from the Laboratory of the Atmosphere and the Oceans (LAO) at IC3 have performed an intercomparison study at the DEC3 site between three different Picarro analyzers (two Picarro G2301 and one Picarro G2301M), a Los Gatos Research (LGR) analyzer and the GC system already installed at the station. The aim of this study is to compare and assess the measuring agreement between the four optical gas analyzers and the GC. In the first part of the experiment, all instruments have been calibrated using NOAA gases as primary standards analyzing five Praxair provided targets to evaluate the precision of the measuring instruments. Max Plank Institute (MPI) gases have been used as secondary standards for the GC whereas Praxair provided tanks are used as secondary standards for the Picarro and the LGR analyzers. In the second part of the experiment, atmospheric GHG were measured from natural atmospheric air taken from a 10 m a.g.l. inlet. Daily cycles of GHG measurements were carried out using different

  16. Measuring Crowdedness between Adjacent Stations in an Urban Metro System: a Chinese Case Study

    Directory of Open Access Journals (Sweden)

    Liudan Jiao

    2017-12-01

    Full Text Available The urban metro system has been widely appreciated as the most important component in urban infrastructures. It plays a critical role in promoting urban social and economic development, and particularly in reducing the urban traffic congestion. However, there are various inherent problems with operating metro systems, which typically involve the crowdedness both at stations and inside vehicles. Both policymakers and academic researchers in China have paid little attention to the crowdedness between metro stations. In order to solve the problem of crowdedness, it is necessary to develop a method to evaluate the level of crowdedness. This work establishes a model to measure the crowdedness between adjacent stations in a metro system based on the load factor principle, passenger standing density, and other factors such as the metro operation schedule and estimations of passenger flows. The Chongqing Metro Line 3 in China is used as a case study to demonstrate the application of the evaluation model. The case study reveals that the model introduced in this study can assist with assessing the crowdedness level between adjacent stations in a metro line. The model is an effective tool for helping the metro management and administration understand the level of crowdedness, apply proper methods to mitigate the crowdedness, and thus improve the quality of the service for those utilizing the metro system.

  17. History of measures taken to reduce radiation exposure at Hamaoka Nuclear Power Station

    International Nuclear Information System (INIS)

    Kondou, Masashi; Takagi, Nobuyuki; Yabushita, Kazuo; Dekijima, Makoto

    2009-01-01

    Hamaoka Nuclear Power Station currently has five reactors, Units 1 to 5. Units 1 and 2 halted commercial operation in January 2009 and are now being prepared for decommissioning. Units 3 to 5 are operating at the rated thermal output with the gross electrical output of 3504 MWe. Hamaoka Nuclear Power Station has been operating for about 30 years since Unit 1 started up in 1976. Various measures have been taken to control water chemistry: for controlling SCC in the core internals and structural materials, hydrogen injection and noble metal injection were implemented; and to reduce radiation exposure for workers, condensate filter demineralizers were added, hollow fiber filters and pleated filters were installed in the condensate cleanup system, and zinc injection was performed. This paper describes measures taken at Hamaoka to reduce exposure in terms of water chemistry and techniques to monitor ion impurities in the reactor water. (author)

  18. Trends in Surface-Water Quality at Selected Ambient-Monitoring Network Stations in Kentucky, 1979-2004

    Science.gov (United States)

    Crain, Angela S.; Martin, Gary R.

    2009-01-01

    Increasingly complex water-management decisions require water-quality monitoring programs that provide data for multiple purposes, including trend analyses, to detect improvement or deterioration in water quality with time. Understanding surface-water-quality trends assists resource managers in identifying emerging water-quality concerns, planning remediation efforts, and evaluating the effectiveness of the remediation. This report presents the results of a study conducted by the U.S. Geological Survey, in cooperation with the Kentucky Energy and Environment Cabinet-Kentucky Division of Water, to analyze and summarize long-term water-quality trends of selected properties and water-quality constituents in selected streams in Kentucky's ambient stream water-quality monitoring network. Trends in surface-water quality for 15 properties and water-quality constituents were analyzed at 37 stations with drainage basins ranging in size from 62 to 6,431 square miles. Analyses of selected physical properties (temperature, specific conductance, pH, dissolved oxygen, hardness, and suspended solids), for major ions (chloride and sulfate), for selected metals (iron and manganese), for nutrients (total phosphorus, total nitrogen, total Kjeldahl nitrogen, nitrite plus nitrate), and for fecal coliform were compiled from the Commonwealth's ambient water-quality monitoring network. Trend analyses were completed using the S-Plus statistical software program S-Estimate Trend (S-ESTREND), which detects trends in water-quality data. The trend-detection techniques supplied by this software include the Seasonal Kendall nonparametric methods for use with uncensored data or data censored with only one reporting limit and the Tobit-regression parametric method for use with data censored with multiple reporting limits. One of these tests was selected for each property and water-quality constituent and applied to all station records so that results of the trend procedure could be compared among

  19. Surface temperature measurement with radioactive kryptonates

    International Nuclear Information System (INIS)

    Pruzinec, J.; Piatrik, M.

    1976-01-01

    The preparation and use of radioactive kryptonates is described for measuring surface temperatures within the region of 45 to 70 degC. Two samples each were prepared of kryptonated beechwood and hydroquinone on a paper carrier. One sample served as the standard which during the experiment was placed in a thermostat at a constant temperature of 45 degC. The second sample was placed in another thermostat where the temperature changed from 45 to 70 degC. Both samples were in the thermostat for 30 mins. The temperature was raised in steps of 2.5 degC and the time of measurement was constant in both samples. The dependences are given of the drop in activity on temperature for both types of samples. The difference was determined of the drop in activity between the standard and the second sample and the relation for measuring the temperature of the sample was determined therefrom. (J.B.)

  20. Tissue equivalent detector measurements on Mir space station. Comparison with other data

    Energy Technology Data Exchange (ETDEWEB)

    Bottollier-Depois, J.F. [CEA Centre d`Etudes de Fontenay-aux-Roses, 92 (France). Dept. de Protection de la Sante de l`Homme et de Dosimetrie; Siegrist, M. [Centre National d`Etudes Spatiales (CNES), 31 - Toulouse (France); Duvivier, E.; Almarcha, B. [STEEL Technologies, Mazeres sur Salat (France); Dachev, T.P.; Semkova, J.V. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Central Lab. of Solar Energy and New Energy Sources; Petrov, V.M.; Bengin, V.; Koslova, S.B. [Institute of Biomedical Problems, Moscow (Russian Federation)

    1995-12-31

    The measurement of the dose received by the cosmonauts, due to cosmic radiations, during a space mission is an important parameter to estimate the radiological risk. Tissue equivalent measurements of radiation environment inside the MIR space station were performed continuously since July 1992. Interesting results about radiation measurements show (a) the South Atlantic Anomaly (SAA) crossing, (c) the increase of radiation near the poles and (d) the effects of solar eruptions. These data are compared with solid state detector (SSD) and other tissue equivalent proportional counter (TEPC) results. (authors). 4 refs., 7 figs.

  1. An in situ measurement of the radio-frequency attenuation in ice at Summit Station, Greenland

    OpenAIRE

    Avva, J.; Kovac, J. M.; Miki, C.; Saltzberg, D.; Vieregg, A. G.

    2014-01-01

    We report an in situ measurement of the electric field attenuation length Lα at radio frequencies for the bulk ice at Summit Station, Greenland, made by broadcasting radio-frequency signals vertically through the ice and measuring the relative power in the return ground bounce signal. We find the depth-averaged field attenuation length to be hLαi = 947+92 −85 m at 75 MHz. While this measurement has clear radioglaciological applications, the radio clarity of the ice also has implications for t...

  2. Tissue equivalent detector measurements on Mir space station. Comparison with other data

    International Nuclear Information System (INIS)

    Bottollier-Depois, J.F.; Duvivier, E.; Almarcha, B.; Dachev, T.P.; Semkova, J.V.

    1995-01-01

    The measurement of the dose received by the cosmonauts, due to cosmic radiations, during a space mission is an important parameter to estimate the radiological risk. Tissue equivalent measurements of radiation environment inside the MIR space station were performed continuously since July 1992. Interesting results about radiation measurements show (a) the South Atlantic Anomaly (SAA) crossing, (c) the increase of radiation near the poles and (d) the effects of solar eruptions. These data are compared with solid state detector (SSD) and other tissue equivalent proportional counter (TEPC) results. (authors). 4 refs., 7 figs

  3. Tethered balloon operation for wintering aerosol measurements in the lower troposphere at Syowa Station, Antarctica

    Directory of Open Access Journals (Sweden)

    Keiichiro Hara

    2007-03-01

    Full Text Available The 46th Japanese Antarctic Research Expedition (JARE-46 carried out twenty seven tethered-balloon-borne aerosol measurements at Syowa Station for better understanding of aerosol chemical and physical properties in the lower troposphere from 6th January 2005 until 11 December 2005. This report summarizes the plan, preparation, field activities and some troubles/problems in the tethered-balloon observations.

  4. Measurement and removal of surface contamination

    International Nuclear Information System (INIS)

    Neider, M.; Tamberg, T.

    1990-01-01

    This is a critical reappraisal of the sampling factor which is important for indirect contamination measurement. The factor gives the radioactivity collected by means of a wipe sample as a fraction of the total loose radioactivity i.e. without firm adhesion. It is used in national and international standard specifications and stated, frequently with excessive conservatism, as 0.1. Secondly, the standard specifications for the testing and appraisal of surface materials in relation to their decontamination capacity and for testing the effect of decontamination agents hitherto bond and Co-60 and Cs-137 are to be expanded to include radioactive iodine, which is important in nuclear medicine. The selection of optimum surface materials will thus be put on an improved basis. (orig./DG) [de

  5. 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.

  6. Detecting earthquakes over a seismic network using single-station similarity measures

    Science.gov (United States)

    Bergen, Karianne J.; Beroza, Gregory C.

    2018-06-01

    New blind waveform-similarity-based detection methods, such as Fingerprint and Similarity Thresholding (FAST), have shown promise for detecting weak signals in long-duration, continuous waveform data. While blind detectors are capable of identifying similar or repeating waveforms without templates, they can also be susceptible to false detections due to local correlated noise. In this work, we present a set of three new methods that allow us to extend single-station similarity-based detection over a seismic network; event-pair extraction, pairwise pseudo-association, and event resolution complete a post-processing pipeline that combines single-station similarity measures (e.g. FAST sparse similarity matrix) from each station in a network into a list of candidate events. The core technique, pairwise pseudo-association, leverages the pairwise structure of event detections in its network detection model, which allows it to identify events observed at multiple stations in the network without modeling the expected moveout. Though our approach is general, we apply it to extend FAST over a sparse seismic network. We demonstrate that our network-based extension of FAST is both sensitive and maintains a low false detection rate. As a test case, we apply our approach to 2 weeks of continuous waveform data from five stations during the foreshock sequence prior to the 2014 Mw 8.2 Iquique earthquake. Our method identifies nearly five times as many events as the local seismicity catalogue (including 95 per cent of the catalogue events), and less than 1 per cent of these candidate events are false detections.

  7. Statistical analysis of electromagnetic radiation measurements in the vicinity of indoor microcell GSM/UMTS base stations in Serbia.

    Science.gov (United States)

    Koprivica, Mladen; Petrić, Majda; Nešković, Nataša; Nešković, Aleksandar

    2016-01-01

    To determine the level of radiofrequency radiation generated by base stations of Global System for Mobile Communications and Universal Mobile Telecommunication System, extensive electromagnetic field strength measurements were carried out in the vicinity of 664 base station locations. These were classified into three categories: indoor, masts, and locations with installations on buildings. Although microcell base stations with antennas installed indoors typically emit less power than outdoor macrocell base stations, the fact that people can be found close to antennas requires exposure originating from these base stations to be carefully considered. Measurement results showed that maximum recorded value of electric field strength exceeded International Commission on Non-Ionizing Radiation Protection reference levels at 7% of indoor base station locations. At the same time, this percentage was much lower in the case of masts and installations on buildings (0% and 2.5%, respectively). © 2015 Wiley Periodicals, Inc.

  8. 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.

  9. Modified SPC for short run test and measurement process in multi-stations

    Science.gov (United States)

    Koh, C. K.; Chin, J. F.; Kamaruddin, S.

    2018-03-01

    Due to short production runs and measurement error inherent in electronic test and measurement (T&M) processes, continuous quality monitoring through real-time statistical process control (SPC) is challenging. Industry practice allows the installation of guard band using measurement uncertainty to reduce the width of acceptance limit, as an indirect way to compensate the measurement errors. This paper presents a new SPC model combining modified guard band and control charts (\\bar{\\text{Z}} chart and W chart) for short runs in T&M process in multi-stations. The proposed model standardizes the observed value with measurement target (T) and rationed measurement uncertainty (U). S-factor (S f) is introduced to the control limits to improve the sensitivity in detecting small shifts. The model was embedded in automated quality control system and verified with a case study in real industry.

  10. LOFT fuel rod surface temperature measurement testing

    International Nuclear Information System (INIS)

    Eaton, A.M.; Tolman, E.L.; Solbrig, C.W.

    1978-01-01

    Testing of the LOFT fuel rod cladding surface thermocouples has been performed to evaluate how accurately the LOFT thermocouples measure the cladding surface temperature during a loss-of-coolant accident (LOCA) sequence and what effect, if any, the thermocouple would have on core performance. Extensive testing has been done to characterize the thermocouple design. Thermal cycling and corrosion testing of the thermocouple weld design have provided an expected lifetime of 6000 hours when exposed to reactor coolant conditions of 620 K and 15.9 MPa and to sixteen thermal cycles with an initial temperature of 480 K and peak temperatures ranging from 870 to 1200K. Departure from nucleate boiling (DNB) tests have indicated a DNB penalty (5 to 28% lower) during steady state operation and negligible effects during LOCA blowdown caused by the LOFT fuel rod surface thermocouple arrangement. Experience with the thermocouple design in Power Burst Facility (PBF) and LOFT nonnuclear blowdown testing has been quite satisfactory. Tests discussed here were conducted using both stainless steel and zircaloy-clad electrically heated rod in the LOFT Test Support Facility (LTSF) blowdown simulation loop

  11. Measuring Transit Oriented Development of Existing Urban Areas around Metro Stations in Faridabad City

    Directory of Open Access Journals (Sweden)

    Sat Pal

    2018-01-01

    Full Text Available Urban population in Indian cities is encouraging auto reliance and having unsafe economic, social and environmental consequences. Land-use-change patterns are the outcome of the complex relations between the human and the physical surroundings. To address these issues the planners are moving beyond land use planning to a sustainable development. Transit and Land use planning are important components to achieve sustainable future of urban development. TOD is a planning tool to encourage this integration. This paper discusses the land use scenario and opportunity around four Metro transit stations in Faridabad city. Different methods and various sets of indicators are considered to evaluate and measure TOD index in this study. This study will evaluate and measure the Faridabad city in the context of land use around Metro Stations to support TOD. This paper seeks to answer how to promote walkable communities, compact and transit-oriented development (TOD that incorporates mixed land use development, including neighbourhood schools, retail and business related space and a mix range of housing types within walkable distance. This paper concludes that the stations area which had a low TOD score needs to have policy for improvement. If planned efficiently, TODs can realize the sustainable development with considerable change in the urban development that focuses on pedestrian based neighbourhood planning.

  12. Bacterial DNA of Ocean and Land on the Surface of the International Space Station.

    Science.gov (United States)

    Grebennikova, Tatiana

    A.V. Syroeshkin2, T.V. Grebennikova1, E.V. Shubralova3, V.A. Shuvalov3, O.S. Tsygankov4, V.B. Lapshin2 1D. I. Ivanovsky Virology Institute, Moscow, Russia 2 Academician E. K. Fedorov Institute of Applied Geophysics, Moscow, Russia 3S.P. Korolev Rocket and Space Corporation «Energia» Korolev, Russia 4Central Research Institute of Machine Building, Korolev, Russia Existence of biological molecules as markers of microorganisms in the space environment has always attracted attention of researchers. There is great attention to the search for extraterrestrial life forms [Nicholson W.L. 2009, Kawaguchi Y. et al 2013], and as well as the coping mechanisms of living organisms in the interplanetary space [Hotchin J. et al 1965, Baranov V.M. 2009, Horneck G. et al 2010]. Experiments on American and Japanese segments of the International Space Station (ISS) over the different nature of resistance during prolonged stay in space were conducted [Scalzi G et al 2012, Wassmann M. et al 2012]. As a result of these experiments confirmed the possibility of preserving the viability of organisms in an open space for a long time. Consequence, became interested in the transfer of living matter from the stratosphere to near-Earth space [Smith D.J. 2013]. We hypothesized that viable forms, or at least, intact DNA can be transferred to the orbit of the ISS with the ascending branch of the global electric circuit. Samples of cosmic dust collected from the surface of the window of the ISS during the exit of an astronaut in space. Samples (washes with material of tampons and tampons) which were in vacuo, were analyzed for the presence of bacterial DNA by nested PCR using primers specific DNA genus Mycobacterium, the DNA of the strain of the genus Bacillus anthracis and DNA encoding the bacterial 16S ribosomal RNA after transportation of the samples to Earth. The results of amplification, followed by sequencing and phylogenetic analysis showed the presence in samples of cosmic dust DNA

  13. The use of vertical and horizontal surface displacements at EPOS GNSS stations in Greenland to study ice sheet mass balance

    DEFF Research Database (Denmark)

    Khan, Shfaqat Abbas

    2014-01-01

    The European Plate Observing System (EPOS) includes e.g. seismic and geodetic permanent national monitoring networks on a European scale. The main purpose is to create data platforms for monitoring and study geophysics processes like earthquakes, volcanoes, surface dynamics and tectonics. Here we...... present data from arctic GNSS stations included in the EPOS network. The arctic EPOS GNSS network consists of 16 continuous GPS stations spread across Greenland. This network is able to map the velocity fields associated with, plate motion, postglacial rebound and improve our understanding of tectonic...

  14. On-line gamma spectroscopy measuring station for cover gas monitoring at KNK II

    International Nuclear Information System (INIS)

    Hoffmann, G.; Letz, K.D.

    1980-02-01

    An automated Ge-γ-spectrometer was developed for cover gas monitoring at KNK II which, by the gamma spectra measured, is to allow the following statements to be made on fuel cladding failure: Type, size, variation with time and subsequent development of the failure. In this report the hardware and software will be explained. Besides, an instruction manual was written for the measuring station, which allows to operate it without detailed knowledge of the manuals for the individual hardware components. (orig.) 891 HP/orig. 892 MKO [de

  15. The Full Aperture Backscatter Station Measurement System on the National Ignition Facility

    International Nuclear Information System (INIS)

    Bower, D; McCarville, T; Alvarez, S; Ault, L; Brown, M; Chrisp, M; Damian, C; DeHope, W; Froula, D; Glenzer, S; Grace, S; Gu, K; Holdener, F; Huffer, C; Kamperschroer, J; Kelleher, T; Kimbrough, J

    2004-01-01

    A Full Aperture Backscatter Station (FABS) target diagnostic has been activated on the first four beams of the National Ignition Facility (NIF). Backscattered light from the target propagates back down the beam path into the FABS diagnostic system. FABS measures both stimulated Brillouin scattering (SBS) and stimulated Raman scattering (SRS) with a suite of measurement instruments. Digital cameras and spectrometers record spectrally resolved energy for both P and S polarized light. Streaked spectrometers measure the spectral and temporal behavior of the backscattered light. Calorimeters and fast photodetectors measure the integrated energy and temporal behavior of the light, respectively. This paper provides an overview of the FABS measurements system and detailed descriptions of the diagnostic instruments and the optical path

  16. Some recent results of Russian measurements of surface ozone in Antarctica. A meteorological interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Gruzdev, A.N.; Elokhov, A.S.; Makarov, O.V.; Mokhov, I.I. (Russian Academy of Sciences, Moscow (Russian Federation). Inst. of Atmospheric Physics)

    1993-01-01

    Surface ozone measurements were carried out at Molodezhnaya and Mirny stations in spring 1987-autumn 1988. The data show an annual variation with a summer minimum at 15 ppbv value. The striking feature of the surface ozone record is two types of day-to-day variability. One of the types is characterized by large day-to-day variations with about 10 ppbv magnitude. The likely mechanism of such variations is the vertical transport induced by cyclonic activity. The other type occurs in synoptically quiet periods (frequent in summer) when the day-to-day ozone variations are significant but not so large. The most likely mechanism of these variations is the slope katabatic wind which transports ozone from inside the Antarctic continent. The latitudinal distribution of surface ozone for this period, measured aboard an aircraft, showed a slight increase towards Vostok station. (26 refs., 3 figs.).

  17. The Skipheia Wind Measurement Station. Instrumentation, Wind Speed Profiles and Turbulence Spectra

    Energy Technology Data Exchange (ETDEWEB)

    Aasen, S E

    1995-10-01

    This thesis describes the design of a measurement station for turbulent wind and presents results from an analysis of the collected data. The station is located at Skipheia near the south-west end of Froeya, an island off the coast of Mid-Norway. The station is unique for studies of turbulent winds because of the large numbers of sensors, which are located at various heights above ground up to 100 m, a sampling rate of 0.85 Hz and storage of the complete time series. The frequency of lightning and atmospheric discharges to the masts are quite high and much effort has gone into minimizing the damage caused by lightning activity. A major part of the thesis deals with data analysis and modelling. There are detailed discussions on the various types of wind sensors and their calibration, the data acquisition system and operating experiences with it, the database, data quality control, the wind speed profile and turbulence. 40 refs., 78 figs., 17 tabs.

  18. 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

  19. Metrological and operational performance of measuring systems used in vehicle compressed natural gas filling stations

    Energy Technology Data Exchange (ETDEWEB)

    Velosa, Jhonn F.; Abril, Henry; Garcia, Luis E. [CDT de GAS (Venezuela). Gas Technological Development Center Corporation

    2008-07-01

    Corporation CDT GAS financially supported by the Colombian government through COLCIENCIAS, carried out a study aimed at designing, developing and implementing in Colombia a calibration and metrological verification 'specialized service' for gas meters installed at dispensers of filling stations using compressed natural gas. The results permitted the identification of improving opportunities (in measuring systems, equipment and devices used to deliver natural gas) which are focused on achieving the highest security and reliability of trading processes of CNG for vehicles. In the development of the first stage of the project, metrological type variables were initially considered, but given the importance of the measuring system and its interaction with the various elements involving gas supply to the filling station, the scope of the work done included aspects related to the operational performance, that is, those influencing the security of the users and the metrological performance of the measuring system. The development of the second stage counted on the collaboration of national companies from the sector of CNG for vehicles, which permitted the carrying out of multiple calibrations to the measuring systems installed in the CNG dispensers, thus achieving, in a concrete way, valid and reliable technological information of the implemented procedures. (author)

  20. Development and calibration of an accurate 6-degree-of-freedom measurement system with total station

    International Nuclear Information System (INIS)

    Gao, Yang; Lin, Jiarui; Yang, Linghui; Zhu, Jigui

    2016-01-01

    To meet the demand of high-accuracy, long-range and portable use in large-scale metrology for pose measurement, this paper develops a 6-degree-of-freedom (6-DOF) measurement system based on total station by utilizing its advantages of long range and relative high accuracy. The cooperative target sensor, which is mainly composed of a pinhole prism, an industrial lens, a camera and a biaxial inclinometer, is designed to be portable in use. Subsequently, a precise mathematical model is proposed from the input variables observed by total station, imaging system and inclinometer to the output six pose variables. The model must be calibrated in two levels: the intrinsic parameters of imaging system, and the rotation matrix between coordinate systems of the camera and the inclinometer. Then corresponding approaches are presented. For the first level, we introduce a precise two-axis rotary table as a calibration reference. And for the second level, we propose a calibration method by varying the pose of a rigid body with the target sensor and a reference prism on it. Finally, through simulations and various experiments, the feasibilities of the measurement model and calibration methods are validated, and the measurement accuracy of the system is evaluated. (paper)

  1. Output power distributions of mobile radio base stations based on network measurements

    International Nuclear Information System (INIS)

    Colombi, D; Thors, B; Persson, T; Törnevik, C; Wirén, N; Larsson, L-E

    2013-01-01

    In this work output power distributions of mobile radio base stations have been analyzed for 2G and 3G telecommunication systems. The approach is based on measurements in selected networks using performance surveillance tools part of the network Operational Support System (OSS). For the 3G network considered, direct measurements of output power levels were possible, while for the 2G networks, output power levels were estimated from measurements of traffic volumes. Both voice and data services were included in the investigation. Measurements were conducted for large geographical areas, to ensure good overall statistics, as well as for smaller areas to investigate the impact of different environments. For high traffic hours, the 90th percentile of the averaged output power was found to be below 65% and 45% of the available output power for the 2G and 3G systems, respectively.

  2. Output power distributions of mobile radio base stations based on network measurements

    Science.gov (United States)

    Colombi, D.; Thors, B.; Persson, T.; Wirén, N.; Larsson, L.-E.; Törnevik, C.

    2013-04-01

    In this work output power distributions of mobile radio base stations have been analyzed for 2G and 3G telecommunication systems. The approach is based on measurements in selected networks using performance surveillance tools part of the network Operational Support System (OSS). For the 3G network considered, direct measurements of output power levels were possible, while for the 2G networks, output power levels were estimated from measurements of traffic volumes. Both voice and data services were included in the investigation. Measurements were conducted for large geographical areas, to ensure good overall statistics, as well as for smaller areas to investigate the impact of different environments. For high traffic hours, the 90th percentile of the averaged output power was found to be below 65% and 45% of the available output power for the 2G and 3G systems, respectively.

  3. Mini neutron monitor measurements at the Neumayer III station and on the German research vessel Polarstern

    Science.gov (United States)

    Heber, B.; Galsdorf, D.; Herbst, K.; Gieseler, J.; Labrenz, J.; Schwerdt, C.; Walter, M.; Benadé, G.; Fuchs, R.; Krüger, H.; Moraal, H.

    2015-08-01

    Neutron monitors (NMs) are ground-based devices to measure the variation of cosmic ray intensities, and although being reliable they have two disadvantages: their size as well as their weight. As consequence, [1] suggested the development of a portable, and thus much smaller and lighter, calibration neutron monitor that can be carried to any existing station around the world [see 2; 3]. But this mini neutron monitor, moreover, can also be installed as an autonomous station at any location that provides ’’office” conditions such as a) temperatures within the range of around 0 to less than 40 degree C as well as b) internet and c) power supply. However, the best location is when the material above the NM is minimized. In 2011 a mini Neutron Monitor was installed at the Neumayer III station in Antarctica as well as the German research vessel Polarstern, providing scientific data since January 2014 and October 2012, respectively. The Polarstern, which is in the possession of the Federal Republic of Germany represented by the Ministry of Education and Research and operated by the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research and managed by the shipping company Laeisz, was specially designed for working in the polar seas and is currently one of the most sophisticated polar research vessels worldwide. It spends almost 310 days a year at sea usually being located in the waters of Antarctica between November and March while spending the northern summer months in Arctic waters. Therefore, the vessel scans the rigidity range below the atmospheric threshold and above 10 GV twice a year. In contrast to spacecraft measurements NM data are influenced by variations of the geomagnetic field as well as the atmospheric conditions. Thus, in order to interpret the data a detailed knowledge of the instrument sensitivity with geomagnetic latitude (rigidity) and atmospheric pressure is essential. In order to determine the atmospheric response data from the

  4. Mini neutron monitor measurements at the Neumayer III station and on the German research vessel Polarstern

    International Nuclear Information System (INIS)

    Heber, B; Galsdorf, D; Herbst, K; Gieseler, J; Labrenz, J; Schwerdt, C; Walter, M; Benadé, G; Fuchs, R; Krüger, H; Moraal, H

    2015-01-01

    Neutron monitors (NMs) are ground-based devices to measure the variation of cosmic ray intensities, and although being reliable they have two disadvantages: their size as well as their weight. As consequence, [1] suggested the development of a portable, and thus much smaller and lighter, calibration neutron monitor that can be carried to any existing station around the world [see 2; 3]. But this mini neutron monitor, moreover, can also be installed as an autonomous station at any location that provides ’’office” conditions such as a) temperatures within the range of around 0 to less than 40 degree C as well as b) internet and c) power supply. However, the best location is when the material above the NM is minimized. In 2011 a mini Neutron Monitor was installed at the Neumayer III station in Antarctica as well as the German research vessel Polarstern, providing scientific data since January 2014 and October 2012, respectively. The Polarstern, which is in the possession of the Federal Republic of Germany represented by the Ministry of Education and Research and operated by the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research and managed by the shipping company Laeisz, was specially designed for working in the polar seas and is currently one of the most sophisticated polar research vessels worldwide. It spends almost 310 days a year at sea usually being located in the waters of Antarctica between November and March while spending the northern summer months in Arctic waters. Therefore, the vessel scans the rigidity range below the atmospheric threshold and above 10 GV twice a year. In contrast to spacecraft measurements NM data are influenced by variations of the geomagnetic field as well as the atmospheric conditions. Thus, in order to interpret the data a detailed knowledge of the instrument sensitivity with geomagnetic latitude (rigidity) and atmospheric pressure is essential. In order to determine the atmospheric response data from the

  5. Ice nuclei measurements at a high altitude remote station in the Northern Apennines

    Science.gov (United States)

    Schrod, Jann; Bingemer, Heinz; Haunold, Werner; Curtius, Joachim; Decesari, Stefano; Marinoni, Angela; Rinaldi, Matteo; Bonasoni, Paolo; Cristofanelli, Paolo

    2013-04-01

    During a field campaign of the PEGASOS (Pan-European Gas-AeroSOls-climate interactions Study, http://pegasos.iceht.forth.gr/) project in June 2012 we have made daily ice nucleus measurements on top of the Monte Cimone (44.18° N, 10.70° E, 2165 m asl) in the Northern Apennines at the "O. Vittori" Climate Observatory. Samples were taken at this GAW-WMO Global Station in a six hour rhythm (4 a.m., 10 a.m., 4 p.m. and 10 p.m.) and at increased frequency during specific events (e.g. dust transport episodes). Ice nuclei were measured by an offline technique. Aerosol particles of 40 liters of air were collected by electrostatic precipitation on a silicon substrate. Subsequently the ice nuclei were analyzed in the vacuum diffusion chamber FRIDGE [Klein et al. 2010] (FRankfurt Ice Nuclei Deposition FreezinG Experiment) by exposing the particles to supersaturation with respect to ice (106 % to 119 %) at -8 ° C, -13 ° C and -18 ° C. In our setup ice nuclei are activated in deposition and condensation freezing modes. A camera detects and counts ice crystals grown on ice nuclei. Every ice crystal counted is assumed to represent at least one ice nucleus. The mean IN concentration at Mt. Cimone was 60 IN per liter (at -18 ° C and 119% relative humility over ice), significantly higher than a longstanding mean at Mt. Kleiner Feldberg (30 IN/l), Germany for June. A mean active site density (IN per surface area of large aerosol particles) of 2.3 * 109 m-2 was calculated. The origin of the air masses sampled was established based on backward trajectories. With more than 100 IN/l on average (at -18° C and 119% relative humility over ice) the samples originating from North Africa were highest, and activated fractions were 4 to 20 times higher than for other transport sectors. An intensive event of dust transport was recorded by several instruments in the middle of June. At its peak in the morning of the 21st of June large aerosol surface and mass concentrations were observed by

  6. A large-scale measurement of electromagnetic fields near GSM base stations in Guangxi, China for risk communication.

    Science.gov (United States)

    Wu, Tongning; Shao, Qing; Yang, Lei; Qi, Dianyuan; Lin, Jun; Lin, Xiaojun; Yu, Zongying

    2013-06-01

    Radiofrequency (RF) electromagnetic field (EMF) exposure from wireless telecommunication base station antennae can lead to debates, conflicts or litigations among the adjacent residents if inappropriately managed. This paper presents a measurement campaign for the GSM band EMF exposure in the vicinity of 827 base station sites (totally 6207 measurement points) in Guangxi, China. Measurement specifications are designed for risk communication with the residents who previously complained of over-exposure. The EMF power densities with the global positioning system coordinate at each measured point were recorded. Compliance with the International Commission on Non-Ionizing Radiation Protection guidelines and Chinese environmental EMF safety standards was studied. The results show that the GSM band EMF level near the base stations is very low. The measurement results and the EMF risk communication procedures positively influence public perception of the RF EMF exposure from the base stations and promote the exchange of EMF exposure-related knowledge.

  7. A large-scale measurement of electromagnetic fields near GSM base stations in Guangxi, China for risk communication

    International Nuclear Information System (INIS)

    Wu, T.; Shao, Q.; Yang, L.; Qi, D.; Lin, J.; Lin, X.; Yu, Z.

    2013-01-01

    Radiofrequency (RF) electromagnetic field (EMF) exposure from wireless telecommunication base station antennae can lead to debates, conflicts or litigations among the adjacent residents if inappropriately managed. This paper presents a measurement campaign for the GSM band EMF exposure in the vicinity of 827 base station sites (totally 6207 measurement points) in Guangxi, China. Measurement specifications are designed for risk communication with the residents who previously complained of over-exposure. The EMF power densities with the global positioning system coordinate at each measured point were recorded. Compliance with the International Commission on Non-Ionizing Radiation Protection guidelines and Chinese environmental EMF safety standards was studied. The results show that the GSM band EMF level near the base stations is very low. The measurement results and the EMF risk communication procedures positively influence public perception of the RF EMF exposure from the base stations and promote the exchange of EMF exposure-related knowledge. (authors)

  8. Statistical analysis of electromagnetic radiation measurements in the vicinity of GSM/UMTS base station antenna masts.

    Science.gov (United States)

    Koprivica, Mladen; Neskovic, Natasa; Neskovic, Aleksandar; Paunovic, George

    2014-01-01

    As a result of dense installations of public mobile base station, additional electromagnetic radiation occurs in the living environment. In order to determine the level of radio-frequency radiation generated by base stations, extensive electromagnetic field strength measurements were carried out for 664 base station locations. Base station locations were classified into three categories: indoor, masts and locations with installations on buildings. Having in mind the large percentage (47 %) of sites with antenna masts, a detailed analysis of this location category was performed, and the measurement results were presented. It was concluded that the total electric field strength in the vicinity of base station antenna masts in no case exceeded 10 V m(-1), which is quite below the International Commission on Non-Ionizing Radiation Protection reference levels. At horizontal distances >50 m from the mast bottom, the median and maximum values were <1 and 2 V m(-1), respectively.

  9. Statistical analysis of electromagnetic radiation measurements in the vicinity of GSM/UMTS base station antenna masts

    International Nuclear Information System (INIS)

    Koprivica, M.; Neskovic, N.; Neskovic, A.; Paunovic, G.

    2014-01-01

    As a result of dense installations of public mobile base station, additional electromagnetic radiation occurs in the living environment. In order to determine the level of radio-frequency radiation generated by base stations, extensive electromagnetic field strength measurements were carried out for 664 base station locations. Base station locations were classified into three categories: indoor, masts and locations with installations on buildings. Having in mind the large percentage (47 %) of sites with antenna masts, a detailed analysis of this location category was performed, and the measurement results were presented. It was concluded that the total electric field strength in the vicinity of base station antenna masts in no case exceeded 10 V m -1 , which is quite below the International Commission on Non-Ionizing Radiation Protection reference levels. At horizontal distances >50 m from the mast bottom, the median and maximum values were -1 , respectively. (authors)

  10. Tethered balloon-borne aerosol measurements: seasonal and vertical variations of aerosol constituents over Syowa Station, Antarctica

    Directory of Open Access Journals (Sweden)

    K. Hara

    2013-09-01

    Full Text Available Tethered balloon-borne aerosol measurements were conducted at Syowa Station, Antarctica, during the 46th Japanese Antarctic expedition (2005–2006. Direct aerosol sampling was operated from near the surface to the lower free troposphere (approximately 2500 m using a balloon-borne aerosol impactor. Individual aerosol particles were analyzed using a scanning electron microscope equipped with an energy dispersive X-ray spectrometer. Seasonal and vertical features of aerosol constituents and their mixing states were investigated. Results show that sulfate particles were predominant in the boundary layer and lower free troposphere in summer, whereas sea-salt particles were predominant during winter through spring. Minerals, MgSO4, and sulfate containing K were identified as minor aerosol constituents in both boundary layer and free troposphere over Syowa Station. Although sea-salt particles were predominant during winter through spring, the relative abundance of sulfate particles increased in the boundary layer when air masses fell from the free troposphere over the Antarctic coast and continent. Sea-salt particles were modified considerably through heterogeneous reactions with SO42− CH3SO3− and their precursors during summer, and were modified slightly through heterogeneous reactions with NO3− and its precursors. During winter through spring, sea-salt modification was insignificant, particularly in the cases of high relative abundance of sea-salt particles and higher number concentrations. In August, NO3− and its precursors contributed greatly to sea-salt modification over Syowa Station. Because of the occurrence of sea-salt fractionation on sea ice, Mg-rich sea-salt particles were identified during the months of April through November. In contrast, Mg-free sea-salt particles and slightly Mg-rich sea-salt particles coexisted in the lower troposphere during summer. Thereby, Mg separation can proceed by sea-salt fractionation during summer in

  11. Comparative Measurement of Microcystins in Diverse Surface ...

    Science.gov (United States)

    The measurement of microcystins, cyanotoxins associated with cyanobacterial blooms which are increasingly prevalent in inland waters, is complicated by the diversity of congeners which have been observed in the environment. At present, more than 150 microcystin congeners have been identified, and this poses a significant challenge to analytical methods intended to assess human health risks in surface and drinking water systems. The most widely employed analytical method at present is the ADDA-ELISA technique which is potentially sensitive to all microcystins, but it is primarily intended as a semi-quantitative method, and questions have been raised regarding the potential for cross-reactivity and false positives. LC-MS/MS methods targeting specific congeners, such as US EPA Method 544, are intended for use as a secondary confirmation following a positive ELISA response, but these techniques can target only those congeners for which commercial standards are available. Accordingly, they are not suitable for ascertaining the safety of a given water sample, given the potential for omitting unknown microcystin congeners which might be present.An alternative approach involves oxidative transformation of microcystins to a common product, 2-methyl-3-methoxy-4-phenylbutyric acid, or MMPB. Measuring MMPB by LC-MS/MS can potentially provide a metric for the sum of all microcystin congeners present in a sample, subject to the efficiency and overall yield of conversion. The

  12. Measurement uncertainty recapture (MUR) power uprates operation at Kuosheng Nuclear Power Station

    International Nuclear Information System (INIS)

    Chang Chinjang; Wang Tunglu; Lin Chihpao

    2009-01-01

    Measurement Uncertainty Recapture PowerUprates (MUR PU) are achieved through the use of state-of-the-art feedwater flow measurement devices, i.e., ultrasonic flow meters (UFMs), that reduce the degree of uncertainty associated with feedwater flow measurement and in turn provide for a more accurate calculation of thermal power. The Institute of Nuclear Energy Research (INER) teamed with Sargent and Lundy, LLC (S and L), Pacific Engineers and Constructors, Ltd (PECL), and AREVA to develop a program and plan for the Kuosheng Nuclear Power Station (KNPS) MUR PU Engineering Service Project and for the assistance to Kuosheng MUR PU operation. After regulator's approval of the licensing requests, KSNPS conducted the power ascension test and switchover to the new rated thermal power for Unit 2 and Unit 1 on 7/7/2007 and 11/30/2007, respectively. From then on, KNPS became the first nuclear power plant implementing MUR PU operation in Taiwan and in Asia. (author)

  13. Confirmatory Survey Results for the Reactor Building Dome Upper Structural Surfaces, Rancho Saco Nuclear Generating Station, Herald, California

    International Nuclear Information System (INIS)

    Wade C. Adams

    2006-01-01

    Results from a confirmatory survey of the upper structural surfaces of the Reactor Building Dome at the Rancho Seco Nuclear Generating Station (RSNGS) performed by the Oak Ridge Institute for Science and Education for the NRC. Also includes results of interlaboratory comparison analyses on several archived soil samples that would be provided by RSNGS personnel. The confirmatory surveys were performed on June 7 and 8, 2006

  14. Measurement and evaluation of thermal effects in the intermixing zone at low power nuclear station outfall

    International Nuclear Information System (INIS)

    Kamath, P.R.; Gurg, R.P.; Bhat, I.S.; Vyas, P.V.

    1978-01-01

    Observations and evaluations of thermal effects in the lake near the RAPS-1 REACTOR, are reported. The coolant waters are drawn from the lake at a depth of 8-10 m below the surface and discharged through an open channel with a temperature rise of 10deg C. Temperature profiles and spread in the velocity of the outfall are mapped using in situ monitors. These studies show evidence of thermal stratification in the period following winter and the existence of a well established thermocline. Parasitism and eutrophication are also observed. The thermal effects are found to be accentuated by photosynthetic effects. Proposal to utilise waste heat for algal culture in the Kalpakkam nuclear site in South and mariculture (lobsters, prawns) in the heated effluents canal at the Tarapur Atomic Power Station near Bombay are discussed. (K.B.)

  15. Experimental measurements of negative hydrogen ion production from surfaces

    International Nuclear Information System (INIS)

    Graham, W.G.

    1977-09-01

    Experimental measurements of the production of H - from surfaces bombarded with hydrogen are reviewed. Some measurements of H + and H 0 production from surfaces are also discussed with particular emphasis on work which might be relevant to ion source applications

  16. A gas chromatograph system for semi-continuous greenhouse gas measurements at Puy de Dôme station, Central France

    Science.gov (United States)

    Lopez, M.; Schmidt, M.; Ramonet, M.; Bonne, J.-L.; Colomb, A.; Kazan, V.; Laj, P.; Pichon, J.-M.

    2015-03-01

    Three years of greenhouse gases measurements, obtained using a gas chromatograph (GC) system located at the Puy de Dôme station at 1465 m a.s.l. in Central France are presented. The GC system was installed in 2010 at Puy de Dôme and was designed for automatic and accurate semi-continuous measurements of atmospheric carbon dioxide, methane, nitrous oxide and sulfur hexafluoride mole fractions. We present in detail the instrumental set up and the calibration strategy, which together allow the GC to reach repeatabilities of 0.1 μmol mol-1, 1.2, 0.3 nmol mol-1 and 0.06 pmol mol-1 for CO2, CH4, N2O and SF6, respectively. Comparisons of the atmospheric time series with those obtained using other instruments shown that the GC system meets the World Meteorological Organization recommendations. The analysis of the three-year atmospheric time series revealed how the planetary boundary layer height drives the mole fractions observed at a mountain site such as Puy de Dôme where air masses alternate between the planetary boundary layer and the free troposphere. Accurate long-lived greenhouse gases measurements collocated with 222Rn measurements as an atmospheric tracer, allowed us to determine the CO2, CH4 and N2O emissions in the catchment area of the station. The derived CO2 surface flux revealed a clear seasonal cycle with net uptake by plant assimilation in the spring and net emission caused by the biosphere and burning of fossil fuel during the remainder of the year. We calculated a mean annual CO2 flux of 1150 t(CO2) km-2. The derived CH4 and N2O emissions in the station catchment area were 5.6 t(CH4) km-2 yr-1 and 1.5 t(N2O) km-2 yr-1, respectively. Our derived annual CH4 flux is in agreement with the national French inventory, whereas our derived N2O flux is five times larger than the same inventory.

  17. Three years of semicontinuous greenhouse gas measurements at the Puy de Dôme station (central France)

    Science.gov (United States)

    Lopez, M.; Schmidt, M.; Ramonet, M.; Bonne, J.-L.; Colomb, A.; Kazan, V.; Laj, P.; Pichon, J.-M.

    2015-09-01

    Three years of greenhouse gas measurements, obtained using a gas chromatograph (GC) system located at the Puy de Dôme station at 1465 m a.s.l. in central France, are presented. The GC system was installed in 2010 at Puy de Dôme and was designed for automatic and accurate semicontinuous measurements of atmospheric carbon dioxide, methane, nitrous oxide and sulfur hexafluoride mole fractions. We present in detail the instrumental setup and the calibration strategy, which together allow the GC to reach repeatabilities of 0.1 μmol mol-1, 1.2 nmol mol-1, 0.3 nmol mol-1 and 0.06 pmol mol-1 for CO2, CH4, N2O and SF6, respectively. The analysis of the 3-year atmospheric time series revealed how the planetary boundary layer height drives the mole fractions observed at a mountain site such as Puy de Dôme where air masses alternate between the planetary boundary layer and the free troposphere. Accurate long-lived greenhouse gas measurements collocated with 222Rn measurements as an atmospheric tracer allowed us to determine the CO2, CH4 and N2O emissions in the catchment area of the station. The derived CO2 surface flux revealed a clear seasonal cycle, with net uptake by plant assimilation in the spring and net emission caused by the biosphere and burning of fossil fuel during the remainder of the year. We calculated a mean annual CO2 flux of 1310 ± 680 t CO2 km-2. The derived CH4 and N2O emissions in the station catchment area were 7.0 ± 4.0 t CH4 km-2 yr-1 and 1.8 ± 1.0 t N2O km-2 yr-1, respectively. Our derived annual CH4 flux is in agreement with the national French inventory, whereas our derived N2O flux is 5 times larger than the same inventory.

  18. Three years of semicontinuous greenhouse gas measurements at the Puy de Dôme station (central France

    Directory of Open Access Journals (Sweden)

    M. Lopez

    2015-09-01

    Full Text Available Three years of greenhouse gas measurements, obtained using a gas chromatograph (GC system located at the Puy de Dôme station at 1465 m a.s.l. in central France, are presented. The GC system was installed in 2010 at Puy de Dôme and was designed for automatic and accurate semicontinuous measurements of atmospheric carbon dioxide, methane, nitrous oxide and sulfur hexafluoride mole fractions. We present in detail the instrumental setup and the calibration strategy, which together allow the GC to reach repeatabilities of 0.1 μmol mol−1, 1.2 nmol mol−1, 0.3 nmol mol−1 and 0.06 pmol mol−1 for CO2, CH4, N2O and SF6, respectively. The analysis of the 3-year atmospheric time series revealed how the planetary boundary layer height drives the mole fractions observed at a mountain site such as Puy de Dôme where air masses alternate between the planetary boundary layer and the free troposphere. Accurate long-lived greenhouse gas measurements collocated with 222Rn measurements as an atmospheric tracer allowed us to determine the CO2, CH4 and N2O emissions in the catchment area of the station. The derived CO2 surface flux revealed a clear seasonal cycle, with net uptake by plant assimilation in the spring and net emission caused by the biosphere and burning of fossil fuel during the remainder of the year. We calculated a mean annual CO2 flux of 1310 ± 680 t CO2 km−2. The derived CH4 and N2O emissions in the station catchment area were 7.0 ± 4.0 t CH4 km−2 yr−1 and 1.8 ± 1.0 t N2O km−2 yr−1, respectively. Our derived annual CH4 flux is in agreement with the national French inventory, whereas our derived N2O flux is 5 times larger than the same inventory.

  19. Upgrade of the SPIRAL identification station for high-precision measurements of nuclear β decay

    Science.gov (United States)

    Grinyer, G. F.; Thomas, J. C.; Blank, B.; Bouzomita, H.; Austin, R. A. E.; Ball, G. C.; Bucaille, F.; Delahaye, P.; Finlay, P.; Frémont, G.; Gibelin, J.; Giovinazzo, J.; Grinyer, J.; Kurtukian-Nieto, T.; Laffoley, A. T.; Leach, K. G.; Lefèvre, A.; Legruel, F.; Lescalié, G.; Perez-Loureiro, D.

    2014-03-01

    The low-energy identification station at SPIRAL (Système de Production d'Ions Radioactifs Accélérés en Ligne) has been upgraded for studying the β decays of short-lived radioactive isotopes and to perform high-precision half-life and branching-ratio measurements for superallowed Fermi and isospin T=1/2 mirror β decays. These new capabilities, combined with an existing Paul trap setup for measurements of β-ν angular-correlation coefficients, provide a powerful facility for investigating fundamental properties of the electroweak interaction through nuclear β decays. A detailed description of the design study, construction, and first results obtained from an in-beam commissioning experiment on the β+ decays 14 O and 17F are presented.

  20. Soil moisture characterization of the Valencia anchor station. Ground, aircraft measurements and simulations

    DEFF Research Database (Denmark)

    Lopez-Baeza, E; Antolin, M C; Balling, Jan E.

    2009-01-01

    In the framework of ESA SMOS Mission, the Valencia Anchor Station (VAS) has been selected as a core validation site. Its reasonable homogeneous characteristics make it appropriate to undertake the validation of SMOS Level 2 land products before attempting other more complex areas. Close to SMOS...... launch (2nd Nov. 2009), ESA defined the SMOS Validation Rehearsal Campaign Plan with the aim of testing the readiness, ensemble coordination and speed of operations, to be able to avoid as far as possible any unexpected deficiencies of the plan and procedure during the real Commissioning Phase campaigns......). Together with the ground SM measurements, other ground and meteorological measurements from the VAS area, kindly provided by other institutions, are currently been used to simulate passive microwave brightness temperature to obtain satellite "match ups" for validation purposes and to test the retrieval...

  1. Legislative measures for suppressing emission of nitrogen oxides from thermal power stations

    Energy Technology Data Exchange (ETDEWEB)

    Kotler, V.R.

    1987-11-01

    Reviews measures taken by some countries to control emission of nitrogen oxides from thermal power stations run on solid fuels, mazout and gas. Refers to maximum permissible concentrations of nitrogen oxides in USA (100 mg/m/sup 3/), Canada (460 mg/m/sup 3/), Japan (41-62 mg/m/sup 3/) and several European countries. Discusses legislative measures in FRG (Federal Regulations BImSchG), particularly Instruction No. 13 BImSchV concerning large boilers run on solid fuels or mazout (continuous monitoring of nitrogen oxide emission into atmosphere, equipping old boilers with means of reducing nitrogen oxide emission, reduction of acid rain). Gives maximum permissible concentrations of nitrogen oxides for new boilers agreed by various countries. 5 refs.

  2. ANITA Air Monitoring on the International Space Station: Results Compared to Other Measurements

    Science.gov (United States)

    Honne, A.; Schumann-Olsen, H.; Kaspersen, K.; Limero, T.; Macatangay, A.; Mosebach, H.; Kampf, D.; Mudgett, P. D.; James, J. T.; Tan, G.; hide

    2009-01-01

    ANITA (Analysing Interferometer for Ambient Air) is a flight experiment precursor for a permanent continuous air quality monitoring system on the ISS (International Space Station). For the safety of the crew, ANITA can detect and quantify quasi-online and simultaneously 33 gas compounds in the air with ppm or sub-ppm detection limits. The autonomous measurement system is based on FTIR (Fourier Transform Infra-Red spectroscopy). The system represents a versatile air quality monitor, allowing for the first time the detection and monitoring of trace gas dynamics in a spacecraft atmosphere. ANITA operated on the ISS from September 2007 to August 2008. This paper summarizes the results of ANITA s air analyses with emphasis on comparisons to other measurements. The main basis of comparison is NASA s set of grab samples taken onboard the ISS and analysed on ground applying various GC-based (Gas Chromatography) systems.

  3. Spatial-temporal dynamics of chemical composition of surface snow in East Antarctica along the Progress station-Vostok station transect

    Science.gov (United States)

    Khodzher, T. V.; Golobokova, L. P.; Osipov, E. Yu.; Shibaev, Yu. A.; Lipenkov, V. Ya.; Osipova, O. P.; Petit, J. R.

    2014-05-01

    In January of 2008, during the 53rd Russian Antarctic Expedition, surface snow samples were taken from 13 shallow (0.7 to 1.5 m depth) snow pits along the first tractor traverse from Progress to Vostok stations, East Antarctica. Sub-surface snow/firn layers are dated from 2.1 to 18 yr. The total length of the coast to inland traverse is more than 1280 km. Here we analysed spatial variability of concentrations of sulphate ions and elements and their fluxes in the snow deposited within the 2006-2008 time interval. Anions were analysed by high-performance liquid chromatography (HPLC), and the determination of selected metals, including Na, K, Mg, Ca and Al, was carried out by mass spectroscopy with atomization by induced coupled plasma (ICP-MS). Surface snow concentration records were examined for trends versus distance inland, elevation, accumulation rate and slope gradient. Na shows a significant positive correlation with accumulation rate, which decreases as distance from the sea and altitude increase. K, Ca and Mg concentrations do not show any significant relationship either with distance inland or with elevation. Maximal concentrations of these elements with a prominent Al peak are revealed in the middle part of the traverse (500-600 km from the coast). Analysis of element correlations and atmospheric circulation patterns allow us to suggest their terrestrial origin (e.g. aluminosilicates carried as a continental dust) from the Antarctic nunatak areas. Sulphate concentrations show no significant relationship with distance inland, elevation, slope gradient and accumulation rate. Non-sea salt secondary sulphate is the most important contribution to the total sulphate budget along the traverse. Sulphate of volcanic origin attributed to the Pinatubo eruption (1991) was revealed in the snow pit at 1276 km (depth 120-130 cm).

  4. Probing Anisotropic Surface Properties of Molybdenite by Direct Force Measurements.

    Science.gov (United States)

    Lu, Zhenzhen; Liu, Qingxia; Xu, Zhenghe; Zeng, Hongbo

    2015-10-27

    Probing anisotropic surface properties of layer-type mineral is fundamentally important in understanding its surface charge and wettability for a variety of applications. In this study, the surface properties of the face and the edge surfaces of natural molybdenite (MoS2) were investigated by direct surface force measurements using atomic force microscope (AFM). The interaction forces between the AFM tip (Si3N4) and face or edge surface of molybdenite were measured in 10 mM NaCl solutions at various pHs. The force profiles were well-fitted with classical DLVO (Derjaguin-Landau-Verwey-Overbeek) theory to determine the surface potentials of the face and the edge surfaces of molybdenite. The surface potentials of both the face and edge surfaces become more negative with increasing pH. At neutral and alkaline conditions, the edge surface exhibits more negative surface potential than the face surface, which is possibly due to molybdate and hydromolybdate ions on the edge surface. The point of zero charge (PZC) of the edge surface was determined around pH 3 while PZC of the face surface was not observed in the range of pH 3-11. The interaction forces between octadecyltrichlorosilane-treated AFM tip (OTS-tip) and face or edge surface of molybdenite were also measured at various pHs to study the wettability of molybdenite surfaces. An attractive force between the OTS-tip and the face surface was detected. The force profiles were well-fitted by considering DLVO forces and additional hydrophobic force. Our results suggest the hydrophobic feature of the face surface of molybdenite. In contrast, no attractive force between the OTS-tip and the edge surface was detected. This is the first study in directly measuring surface charge and wettability of the pristine face and edge surfaces of molybdenite through surface force measurements.

  5. Test Station for Magnetization Measurements on Large Quantities of Superconducting Strands

    CERN Document Server

    Le Naour, S; Billan, J; Genest, J

    2001-01-01

    In the superconducting main magnets of the Large Hadron Collider (LHC), persistent currents in the superconductor determine the field quality at injection field. For this reason it is necessary to check the magnetization of the cable strands during their production. During four years, this requires measurements of the width of the strand magnetization hysteresis loop at 0.5 T, 1.9 K, at a rate of up to eight samples per day. This paper describes the design, construction and the first results of a magnetization test station built for this purpose. The samples are cooled in a cryostat, with a 2-m long elliptic tail. This tail is inserted in a normal conducting dipole magnet with a field between ± 1.5 T. Racetrack pick-up coils, integrated in the cryostat, detect the voltage due to flux change, which is then integrated numerically. The sample holder can contain eight strand samples, each 20 cm long. The test station operates in two modes: either the sample is fixed while the external field is changed, or the sa...

  6. A Pseudorange Measurement Scheme Based on Snapshot for Base Station Positioning Receivers.

    Science.gov (United States)

    Mo, Jun; Deng, Zhongliang; Jia, Buyun; Bian, Xinmei

    2017-12-01

    Digital multimedia broadcasting signal is promised to be a wireless positioning signal. This paper mainly studies a multimedia broadcasting technology, named China mobile multimedia broadcasting (CMMB), in the context of positioning. Theoretical and practical analysis on the CMMB signal suggests that the existing CMMB signal does not have the meter positioning capability. So, the CMMB system has been modified to achieve meter positioning capability by multiplexing the CMMB signal and pseudo codes in the same frequency band. The time difference of arrival (TDOA) estimation method is used in base station positioning receivers. Due to the influence of a complex fading channel and the limited bandwidth of receivers, the regular tracking method based on pseudo code ranging is difficult to provide continuous and accurate TDOA estimations. A pseudorange measurement scheme based on snapshot is proposed to solve the problem. This algorithm extracts the TDOA estimation from the stored signal fragments, and utilizes the Taylor expansion of the autocorrelation function to improve the TDOA estimation accuracy. Monte Carlo simulations and real data tests show that the proposed algorithm can significantly reduce the TDOA estimation error for base station positioning receivers, and then the modified CMMB system achieves meter positioning accuracy.

  7. Analysis of the results of the measurements of the Venus atmosphere parameters in the places of landing of the ''Venera-11'' and ''Venera-12'' artificial interplanetary stations

    International Nuclear Information System (INIS)

    Avduevskij, V.S.; Borodin, N.F.; Vasil'ev, V.N.

    1979-01-01

    Presented is the analysis of the results of the Venus atmosphere parameter measurements by the ''Venera 11'' and ''Venera 12'' automatic interplanetary stations. The automatic stations have reached the Venus surface on the 25 and 21.12.1978 in the points with the following coordinates: PHI=-14.0 deg, lambda= 299 deg at the Sun zenith angle of 20.1 deg and PHI=-7 deg, lambda=294 deg at the Sun zenith angle of 25.2 deg, respectively. The measuring of temperature has been carried out on the area of the launching with the use of the brake parachute and whereas the temperature and pressure measuring have been carried out on the launching area with the help of the brake panel. The temperature has been measured by four platinum termometers of resistence with the general full-scale range from 30 to 530 deg C. The atmosphere pressure measurements have been carried out by four manometers with the general full-scale range from 1 to 150 ata. Presented are the measurements of pressure, temperature and height during the station launching time, pressure dependence on temperature, high-altitude profiles of pressure and temperature in the Venus atmosphere. The data on pressure and temperature for higher part of the Venus atmosphere agree satisfactorily with those, obtained by the method of radioscopy with the help of the ''Venera 9'' and ''Venera 10'' automatic atations. Thr results, obtained, are of preliminary character and may be specified in future

  8. Influence of different land surfaces on atmospheric conditions measured by a wireless sensor network

    Science.gov (United States)

    Lengfeld, Katharina; Ament, Felix

    2010-05-01

    Atmospheric conditions close to the surface, like temperature, wind speed and humidity, vary on small scales because of surface heterogeneities. Therefore, the traditional measuring approach of using a single, highly accurate station is of limited representativeness for a larger domain, because it is not able to determine these small scale variabilities. However, both the variability and the domain averages are important information for the development and validation of atmospheric models and soil-vegetation-atmosphere-transfer (SVAT) schemes. Due to progress in microelectronics it is possible to construct networks of comparably cheap meteorological stations with moderate accuracy. Such a network provides data in high spatial and temporal resolution. The EPFL Lausanne developed such a network called SensorScope, consisting of low cost autonomous stations. Each station observes air and surface temperature, humidity, wind direction and speed, incoming solar radiation, precipitations, soil moisture and soil temperature and sends the data via radio communication to a base station. This base station forwards the collected data via GSM/GPRS to a central server. Within the FLUXPAT project in August 2009 we deployed 15 stations as a twin transect near Jülich, Germany. One aim of this first experiment was to test the quality of the low cost sensors by comparing them to more accurate reference measurements. It turned out, that although the network is not highly accurate, the measurements are consistent. Consequently an analysis of the pattern of atmospheric conditions is feasible. For example, we detect a variability of ± 0.5K in the mean temperature at a distance of only 2.3 km. The transect covers different types of vegetation and a small river. Therefore, we analyzed the influence of different land surfaces and the distance to the river on meteorological conditions. On the one hand, some results meet our expectations, e.g. the relative humidity decreases with increasing

  9. Influence of cloud fraction and snow cover to the variation of surface UV radiation at King Sejong station, Antarctica

    Science.gov (United States)

    Lee, Yun Gon; Koo, Ja-Ho; Kim, Jhoon

    2015-10-01

    This study investigated how cloud fraction and snow cover affect the variation of surface ultraviolet (UV) radiation by using surface Erythemal UV (EUV) and Near UV (NUV) observed at the King Sejong Station, Antarctica. First the Radiative Amplification Factor (RAF), the relative change of surface EUV according to the total-column ozone amount, is compared for different cloud fractions and solar zenith angles (SZAs). Generally, all cloudy conditions show that the increase of RAF as SZA becomes larger, showing the larger effects of vertical columnar ozone. For given SZA cases, the EUV transmission through mean cloud layer gradually decreases as cloud fraction increases, but sometimes the maximum of surface EUV appears under partly cloudy conditions. The high surface EUV transmittance under broken cloud conditions seems due to the re-radiation of scattered EUV by cloud particles. NUV transmission through mean cloud layer also decreases as cloud amount increases but the sensitivity to the cloud fraction is larger than EUV. Both EUV and NUV radiations at the surface are also enhanced by the snow cover, and their enhancement becomes higher as SZA increases implying the diurnal variation of surface albedo. This effect of snow cover seems large under the overcast sky because of the stronger interaction between snow surface and cloudy sky.

  10. Seismic velocity site characterization of 10 Arizona strong-motion recording stations by spectral analysis of surface wave dispersion

    Science.gov (United States)

    Kayen, Robert E.; Carkin, Brad A.; Corbett, Skye C.

    2017-10-19

    Vertical one-dimensional shear wave velocity (VS) profiles are presented for strong-motion sites in Arizona for a suite of stations surrounding the Palo Verde Nuclear Generating Station. The purpose of the study is to determine the detailed site velocity profile, the average velocity in the upper 30 meters of the profile (VS30), the average velocity for the entire profile (VSZ), and the National Earthquake Hazards Reduction Program (NEHRP) site classification. The VS profiles are estimated using a non-invasive continuous-sine-wave method for gathering the dispersion characteristics of surface waves. Shear wave velocity profiles were inverted from the averaged dispersion curves using three independent methods for comparison, and the root-mean-square combined coefficient of variation (COV) of the dispersion and inversion calculations are estimated for each site.

  11. Status of the nuclear measurement stations for the process control of spent fuel reprocessing at AREVA NC/La Hague

    International Nuclear Information System (INIS)

    Eleon, Cyrille; Passard, Christian; Hupont, Nicolas; Estre, Nicolas; Battel, Benjamin; Doumerc, Philippe; Dupuy, Thierry; Batifol, Marc; Grassi, Gabriele

    2015-01-01

    Nuclear measurements are used at AREVA NC/La Hague for the monitoring of spent fuel reprocessing. The process control is based on gamma-ray spectroscopy, passive neutron counting and active neutron interrogation, and gamma transmission measurements. The main objectives are criticality and safety, online process monitoring, and the determination of the residual fissile mass and activities in the metallic waste remained after fuel shearing and dissolution (empty hulls, grids, end pieces), which are put in radioactive waste drums before compaction. The whole monitoring system is composed of eight measurement stations which will be described in this paper. The main measurement stations no. 1, 3 and 7 are needed for criticality control. Before fuel element shearing for dissolution, station no. 1 allows determining the burn-up of the irradiated fuel by gamma-ray spectroscopy with HP Ge (high purity germanium) detectors. The burn-up is correlated to the 137 Cs and 134 Cs gamma emission rates. The fuel maximal mass which can be loaded in one bucket of the dissolver is estimated from the lowest burn-up fraction of the fuel element. Station no. 3 is dedicated to the control of the correct fuel dissolution, which is performed with a 137 Cs gamma ray measurement with a HP Ge detector. Station no. 7 allows estimating the residual fissile mass in the drums filled with the metallic residues, especially in the hulls, from passive neutron counting (spontaneous fission and alpha-n reactions) and active interrogation (fission prompt neutrons induced by a pulsed neutron generator) with proportional 3 He detectors. The measurement stations have been validated for the reprocessing of Uranium Oxide (UOX) fuels with a burn-up rate up to 60 GWd/t. This paper presents a brief overview of the current status of the nuclear measurement stations. (authors)

  12. Status of the nuclear measurement stations for the process control of spent fuel reprocessing at AREVA NC/La Hague

    Energy Technology Data Exchange (ETDEWEB)

    Eleon, Cyrille; Passard, Christian; Hupont, Nicolas; Estre, Nicolas [CEA, DEN, Cadarache, Nuclear Measurement Laboratory, F-13108 St Paul-lez-Durance (France); Battel, Benjamin; Doumerc, Philippe; Dupuy, Thierry; Batifol, Marc [AREVA NC, La Hague plant - Nuclear Measurement Team, F-50444 Beaumont-Hague (France); Grassi, Gabriele [AREVA NC, 1 place Jean-Millier, 92084 Paris-La-Defense cedex (France)

    2015-07-01

    Nuclear measurements are used at AREVA NC/La Hague for the monitoring of spent fuel reprocessing. The process control is based on gamma-ray spectroscopy, passive neutron counting and active neutron interrogation, and gamma transmission measurements. The main objectives are criticality and safety, online process monitoring, and the determination of the residual fissile mass and activities in the metallic waste remained after fuel shearing and dissolution (empty hulls, grids, end pieces), which are put in radioactive waste drums before compaction. The whole monitoring system is composed of eight measurement stations which will be described in this paper. The main measurement stations no. 1, 3 and 7 are needed for criticality control. Before fuel element shearing for dissolution, station no. 1 allows determining the burn-up of the irradiated fuel by gamma-ray spectroscopy with HP Ge (high purity germanium) detectors. The burn-up is correlated to the {sup 137}Cs and {sup 134}Cs gamma emission rates. The fuel maximal mass which can be loaded in one bucket of the dissolver is estimated from the lowest burn-up fraction of the fuel element. Station no. 3 is dedicated to the control of the correct fuel dissolution, which is performed with a {sup 137}Cs gamma ray measurement with a HP Ge detector. Station no. 7 allows estimating the residual fissile mass in the drums filled with the metallic residues, especially in the hulls, from passive neutron counting (spontaneous fission and alpha-n reactions) and active interrogation (fission prompt neutrons induced by a pulsed neutron generator) with proportional {sup 3}He detectors. The measurement stations have been validated for the reprocessing of Uranium Oxide (UOX) fuels with a burn-up rate up to 60 GWd/t. This paper presents a brief overview of the current status of the nuclear measurement stations. (authors)

  13. Measurement of Deformations by MEMS Arrays, Verified at Sub-millimetre Level Using Robotic Total Stations

    Directory of Open Access Journals (Sweden)

    Tomas Beran

    2014-06-01

    Full Text Available Measurement of sub-millimetre-level deformations of structures in the presence of ambienttemperature changes can be challenging. This paper describes the measurement of astructure moving due to temperature changes, using two ShapeAccelArray (SAAinstruments, and verified by a geodetic monitoring system. SAA is a geotechnicalinstrument often used for monitoring of displacements in soil. SAA uses micro-electro-mechanical system (MEMS sensors to measure tilt in the gravity field. The geodeticmonitoring system, which uses ALERT software, senses the displacements of targetsrelative to control points, using a robotic total station (RTS. The test setup consists of acentral four-metre free-standing steel tube with other steel tubes welded to most of itslength. The central tube is anchored in a concrete foundation. This composite “pole” isequipped with two SAAs as well as three geodetic prisms mounted on the top, in the middle,and in the foundation. The geodetic system uses multiple control targets mounted inconcrete foundations of nearby buildings, and at the base of the pole. Long-termobservations using two SAAs indicate that the pole is subject to deformations due to cyclicalambient temperature variations causing the pole to move by a few millimetres each day. Ina multiple-day experiment, it was possible to track this movement using SAA as well as theRTS system. This paper presents data comparing the measurements of the two instrumentsand provides a good example of the detection of two-dimensional movements of seeminglyrigid objects due to temperature changes.

  14. 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

  15. Comparison of parallel temperature measurements from conventional and automatic weather stations at Fabra Observatory (Barcelona).

    Science.gov (United States)

    Aguilar, Enric; Gilabert, Alba; Prohom, Marc

    2013-04-01

    Fabra Observatory , located in a promontory at 411 meters above sea level in the outskirts of Barcelona, hosts a continuous climate record since 1913. Additionally, it has been recording since 1996 simultaneous temperature and precipitation data with conventional instruments and automated systems. The automatization of recording sites employed with climatological purposes is happening elsewhere in the country and across the globe. Unfortunately, in most cases long lasting parallel measurements, are not kept. Thereafter, this site offers an excellent opportunity to study the impact of the introduction of Automatic Weather Stations (AWS). The conventional station (CON) equips a liquid in glass thermometer, located inside a standard Stevenson screen. The automatic measurements (AWS) have been taken using MCV-STA sensors sheltered in a MCV small plate-like ventilated screen between 1996 and the end of July 2007. For our analysis, this MCV period is split in two (T1, T2) due to an obvious jump in the differences AWS-CON in October 2002, produced by unknown reasons. From August 2007 to the present (T3), a Vaisala HMP45AL sensor was placed inside a Stevenson Screen and used for automatic measurements. For daily maximum temperatures, the median differences reach 3.2°C in T1, 1.1°C in T2 and merely -0.1°C in T3. In this later period, 94% of the differences are comprised in a ±0.5°C range, compared to 23% in T2 and only 6% in T1. It is interesting to note how the overheating of the MCV screen dominates the difference series, as 85% of the AWS values taken in T1 and T2 are warmer than the conventional measurements, contrasting with only 27% of cases during T3, when the automated measurements were taken inside a Stevenson screen. These differences are highly temperature dependent: low (high) AWS temperatures are associated with small (large) differences with the CON series. This effect is also evident if temperatures are analyzed by seasons: summer differences are much

  16. [In-situ measurement of atmospheric methyl chloroform at the Shangdianzi GAW regional background station].

    Science.gov (United States)

    Yao, Bo; Zhou, Ling-Xi; Liu, Zhao; Zhang, Gen; Xia, Ling-Jun

    2014-07-01

    An in-situ GC-ECD monitoring system was established at the Shangdianzi GAW regional background station (SDZ) for a 2-year atmospheric methyl chloroform (CH3CCl3) measurement experiment. Robust extraction of baseline signal filter was applied to the CH3CCl3 time series to separate the background and pollution data. The yearly averaged background mixing ratios of atmospheric CH3CCl3 were (9.03 +/- 0.53) x 10(-12) mol x mol(-1) in 2009 and (7.73 +/- 0.47) x 10(-12) in 2010, and the percentages of the background data in the whole data were 61.1% in 2009 and 60.4% in 2010, respectively. The yearly background CH3CCl3 mixing ratios at SDZ were consistent with the northern hemisphere background levels observed at Mace Head and Trinidad Head stations, but lower than the results observed at sites in southern China and some Chinese cities from 2001 to 2005. During the study period, background mixing ratios trends exhibited a decreasing rate of 1.39 x 10 12(-12) a(-1). The wind direction with the maximum CH3CCl3 mixing ratio was from the southwest sector and that with the minimum ratio was from the northeast sector. The differences between the maximum and the minimum average mixing ratios in the 16 wind directions were 0.77 x 10(-12) (2009) and 0.52 x 10(-12) (2010). In the 16 different wind directions, the averaged mixing ratio of CH3CCl3 in 2010 was lower than that in 2009 by 1.03 x 10(-12) -1.68 x 10(-12).

  17. Empirical Requirements Analysis for Mars Surface Operations Using the Flashline Mars Arctic Research Station

    Science.gov (United States)

    Clancey, William J.; Lee, Pascal; Sierhuis, Maarten; Norvig, Peter (Technical Monitor)

    2001-01-01

    Living and working on Mars will require model-based computer systems for maintaining and controlling complex life support, communication, transportation, and power systems. This technology must work properly on the first three-year mission, augmenting human autonomy, without adding-yet more complexity to be diagnosed and repaired. One design method is to work with scientists in analog (mars-like) setting to understand how they prefer to work, what constrains will be imposed by the Mars environment, and how to ameliorate difficulties. We describe how we are using empirical requirements analysis to prototype model-based tools at a research station in the High Canadian Arctic.

  18. Net community production and calcification from 7 years of NOAA Station Papa Mooring measurements

    Science.gov (United States)

    Fassbender, Andrea J.; Sabine, Christopher L.; Cronin, Meghan F.

    2016-02-01

    Seven years of near-continuous observations from the Ocean Station Papa (OSP) surface mooring were used to evaluate drivers of marine carbon cycling in the eastern subarctic Pacific. Processes contributing to mixed layer carbon inventory changes throughout each deployment year were quantitatively assessed using a time-dependent mass balance approach in which total alkalinity and dissolved inorganic carbon were used as tracers. By using two mixed layer carbon tracers, it was possible to isolate the influences of net community production (NCP) and calcification. Our results indicate that the annual NCP at OSP is 2 ± 1 mol C m-2 yr-1 and the annual calcification is 0.3 ± 0.3 mol C m-2 yr-1. Piecing together evidence for potentially significant dissolved organic carbon cycling in this region, we estimate a particulate inorganic carbon to particulate organic carbon ratio between 0.15 and 0.25. This is at least double the global average, adding to the growing evidence that calcifying organisms play an important role in carbon export at this location. These results, coupled with significant seasonality in the NCP, suggest that carbon cycling near OSP may be more complex than previously thought and highlight the importance of continuous observations for robust assessments of biogeochemical cycling.

  19. Application of the nonlinear time series prediction method of genetic algorithm for forecasting surface wind of point station in the South China Sea with scatterometer observations

    International Nuclear Information System (INIS)

    Zhong Jian; Dong Gang; Sun Yimei; Zhang Zhaoyang; Wu Yuqin

    2016-01-01

    The present work reports the development of nonlinear time series prediction method of genetic algorithm (GA) with singular spectrum analysis (SSA) for forecasting the surface wind of a point station in the South China Sea (SCS) with scatterometer observations. Before the nonlinear technique GA is used for forecasting the time series of surface wind, the SSA is applied to reduce the noise. The surface wind speed and surface wind components from scatterometer observations at three locations in the SCS have been used to develop and test the technique. The predictions have been compared with persistence forecasts in terms of root mean square error. The predicted surface wind with GA and SSA made up to four days (longer for some point station) in advance have been found to be significantly superior to those made by persistence model. This method can serve as a cost-effective alternate prediction technique for forecasting surface wind of a point station in the SCS basin. (paper)

  20. Measurement of the energy spectrum of cosmic rays with the 26 station configuration of the IceTop detector

    International Nuclear Information System (INIS)

    Kislat, Fabian

    2011-01-01

    IceTop is an instrument at the geographic South Pole designed to detect cosmic ray air showers, particle cascades in the atmosphere initiated by high-energy cosmic rays. It is the surface component of the IceCube neutrino telescope. Since its completion in December 2010, IceTop consists of 81 detector stations covering an area of one square kilometer on the ice surface above IceCube. Each IceTop station consists of two ice-filled tanks in which the Cherenkov light emitted by charged air shower particles is measured. In this dissertation, an analysis of data taken in 2007 with 26 IceTop stations operational at that time is presented. First, properties of air showers like core position, direction and shower size were reconstructed from the measured signals. The core position can be determined to an accuracy of up to 6m and a direction resolution of up to 0.3 is achieved. The shower size is a measure of the energy of the primary particle and a resolution of up to 10% is achieved at high energies. In the next step the relation between primary energy and shower size, as well as resolution and efficiency are determined from Monte Carlo simulations of air showers and the IceTop detector. Here, an assumption was made about the chemical composition of cosmic rays. The informations obtained in these simulations are then used to unfold the spectrum of measured shower sizes in order to obtain the all-particle cosmic ray energy spectrum. This is done independently for particles from three different zenith angle intervals. The result of the unfolding depends on the assumed primary composition. Due to the isotropy of cosmic rays, results obtained in different zenith angle intervals must agree. While with the chosen analysis technique a simultaneous determination of primary particle mass and energy is limited due to systematic uncertainties, it has already been shown that the requirement of isotropy can be used to constrain the range of possible assumptions on the chemical

  1. Measurement of the energy spectrum of cosmic rays with the 26 station configuration of the IceTop detector

    Energy Technology Data Exchange (ETDEWEB)

    Kislat, Fabian

    2011-09-27

    IceTop is an instrument at the geographic South Pole designed to detect cosmic ray air showers, particle cascades in the atmosphere initiated by high-energy cosmic rays. It is the surface component of the IceCube neutrino telescope. Since its completion in December 2010, IceTop consists of 81 detector stations covering an area of one square kilometer on the ice surface above IceCube. Each IceTop station consists of two ice-filled tanks in which the Cherenkov light emitted by charged air shower particles is measured. In this dissertation, an analysis of data taken in 2007 with 26 IceTop stations operational at that time is presented. First, properties of air showers like core position, direction and shower size were reconstructed from the measured signals. The core position can be determined to an accuracy of up to 6m and a direction resolution of up to 0.3 is achieved. The shower size is a measure of the energy of the primary particle and a resolution of up to 10% is achieved at high energies. In the next step the relation between primary energy and shower size, as well as resolution and efficiency are determined from Monte Carlo simulations of air showers and the IceTop detector. Here, an assumption was made about the chemical composition of cosmic rays. The informations obtained in these simulations are then used to unfold the spectrum of measured shower sizes in order to obtain the all-particle cosmic ray energy spectrum. This is done independently for particles from three different zenith angle intervals. The result of the unfolding depends on the assumed primary composition. Due to the isotropy of cosmic rays, results obtained in different zenith angle intervals must agree. While with the chosen analysis technique a simultaneous determination of primary particle mass and energy is limited due to systematic uncertainties, it has already been shown that the requirement of isotropy can be used to constrain the range of possible assumptions on the chemical

  2. Measurements of nitrous oxide emissions from P.F. fired power stations

    Science.gov (United States)

    Sloan, S. A.; Laird, C. K.

    Nitrous oxide (N 2O) was measured in the flue gas from four wall-fired and three corner-fired 500 MW boilers, fitted with either conventional or low-NO x burners, at four C.E.G.B. power stations. Measurements were made both by on-line non-dispersive infra red (NDIR) monitors and by extractive sampling for later laboratory analysis by electron capture gas chromatography (ECD GC). It was found that the on-line and laboratory methods were in good agreement for samples analyzed within 1-3 h of sampling, but that the nitrous oxide concentration in the stored samples had a tendency to increase with time, which was dependent on the concentration of water in the sample. Experiments with synthetic mixtures showed that the increase in nitrous oxide concentration was consistent with the overall reaction2NO+SO 2→N 2O+SO 3 in which nitric oxide is reduced by sulphur dioxide. The highest average N 2O concentration measured by the on-line analyzer was 16 vpm, and for most of the boilers monitored the concentration was less than 10 vpm. There was no statistically significant difference between the measured N 2O emissions from normal boilers and those fitted with low-NO x burners. It is suggested that these values are close to the true levels of N 2O emissions from p.f. fired boilers and that recent reports of high levels (up to 200 vpm) are likely to be an artefact resulting from the observed generation of N 2O in stored samples. A consequence of these measurements of N 2O is that current estimates of the contribution of emissions from p.f. fired boilers to the global N 2O budget are likely to be too high.

  3. Analysis of the effect of mobile phone base station antenna loading on localized SAR and its consequences for measurements.

    Science.gov (United States)

    Hansson, Björn; Thors, Björn; Törnevik, Christer

    2011-12-01

    In this work, the effect of antenna element loading on the localized specific absorption rate (SAR) has been analyzed for base station antennas. The analysis was conducted in order to determine whether localized SAR measurements of large multi-element base station antennas can be conducted using standardized procedures and commercially available equipment. More specifically, it was investigated if the antenna shifting measurement procedure, specified in the European base station exposure assessment standard EN 50383, will produce accurate localized SAR results for base station antennas larger than the specified measurement phantom. The obtained results show that SAR accuracy is affected by the presence of lossy material within distances of one wavelength from the tested antennas as a consequence of coupling and redistribution of transmitted power among the antenna elements. It was also found that the existing standardized phantom is not optimal for SAR measurements of large base station antennas. A new methodology is instead proposed based on a larger, box-shaped, whole-body phantom. Copyright © 2011 Wiley Periodicals, Inc.

  4. Spin motion determination of the Envisat satellite through laser ranging measurements from a single pass measured by a single station

    Science.gov (United States)

    Pittet, Jean-Noël; Šilha, Jiří; Schildknecht, Thomas

    2018-02-01

    The Satellite Laser Ranging (SLR) technology is used to accurately determine the position of space objects equipped with so-called retro-reflectors or retro-reflector arrays (RRA). This type of measurement allows to measure the range to the spacecraft with high precision, which leads to determination of very accurate orbits for these targets. Non-active spacecraft, which are not attitude controlled any longer, tend to start to spin or tumble under influence of the external and internal torques and forces. If the return signal is measured for a non-spherical non-active rotating object, the signal in the range residuals with respect to the reference orbit is more complex. For rotating objects the return signal shows an oscillating pattern or patterns caused by the RRA moving around the satellite's centre of mass. This behaviour is projected onto the radial component measured by the SLR. In our work, we demonstrate how the SLR ranging technique from one sensor to a satellite equipped with a RRA can be used to precisely determine its spin motion during one passage. Multiple SLR measurements of one target over time allow to accurately monitor spin motion changes which can be further used for attitude predictions. We show our solutions of the spin motion determined for the non-active ESA satellite Envisat obtained from measurements acquired during years 2013-2015 by the Zimmerwald SLR station, Switzerland. All the necessary parameters are defined for our own so-called point-like model which describes the motion of a point in space around the satellite centre of mass.

  5. Estimation of surface heat and moisture fluxes over a prairie grassland. I - In situ energy budget measurements incorporating a cooled mirror dew point hygrometer

    Science.gov (United States)

    Smith, Eric A.; Crosson, William L.; Tanner, Bertrand D.

    1992-01-01

    Attention is focused on in situ measurements taken during FIFE required to support the development and validation of a biosphere model. Seasonal time series of surface flux measurements obtained from two surface radiation and energy budget stations utilized to support the FIFE surface flux measurement subprogram are examined. Data collection and processing procedures are discussed along with the measurement analysis for the complete 1987 test period.

  6. 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

  7. A new fiber optic sensor for inner surface roughness measurement

    Science.gov (United States)

    Xu, Xiaomei; Liu, Shoubin; Hu, Hong

    2009-11-01

    In order to measure inner surface roughness of small holes nondestructively, a new fiber optic sensor is researched and developed. Firstly, a new model for surface roughness measurement is proposed, which is based on intensity-modulated fiber optic sensors and scattering modeling of rough surfaces. Secondly, a fiber optical measurement system is designed and set up. Under the help of new techniques, the fiber optic sensor can be miniaturized. Furthermore, the use of micro prism makes the light turn 90 degree, so the inner side surface roughness of small holes can be measured. Thirdly, the fiber optic sensor is gauged by standard surface roughness specimens, and a series of measurement experiments have been done. The measurement results are compared with those obtained by TR220 Surface Roughness Instrument and Form Talysurf Laser 635, and validity of the developed fiber optic sensor is verified. Finally, precision and influence factors of the fiber optic sensor are analyzed.

  8. Measurements of tritium (HTO, TFWT, OBT) in environmental samples at varying distances from a nuclear generating station

    International Nuclear Information System (INIS)

    Kotzer, T.G.; Workman, W.J.G.

    1999-12-01

    Concentrations of tritium have been measured in environmental samples (vegetation, water, soil, air) from sites distal and proximal to a CANDU nuclear generating station in Southern Ontario (OPG-Pickering). Levels of tissue-free water tritium (TFWT) and organically bound tritium (OBT) in vegetation are as high as 24,000 TU immediately adjacent to the nuclear generating station and rapidly decrease to levels of tritium which are comparable to natural ambient concentrations for tritium in the environment (approximately ≤ 60 TU). Tritium concentrations (OBT, TFTW) have also been measured in samples of vegetation and tree rings growing substantial distances away from nuclear generating stations and are within a factor of 1 to 2 of the ambient levels of tritium measured in precipitation in several parts of Canada (approximately ≤30 TU). (author)

  9. Measurements of tritium (HTO, TFWT, OBT) in environmental samples at varying distances from a nuclear generating station

    Energy Technology Data Exchange (ETDEWEB)

    Kotzer, T.G.; Workman, W.J.G

    1999-12-01

    Concentrations of tritium have been measured in environmental samples (vegetation, water, soil, air) from sites distal and proximal to a CANDU nuclear generating station in Southern Ontario (OPG-Pickering). Levels of tissue-free water tritium (TFWT) and organically bound tritium (OBT) in vegetation are as high as 24,000 TU immediately adjacent to the nuclear generating station and rapidly decrease to levels of tritium which are comparable to natural ambient concentrations for tritium in the environment (approximately {<=} 60 TU). Tritium concentrations (OBT, TFTW) have also been measured in samples of vegetation and tree rings growing substantial distances away from nuclear generating stations and are within a factor of 1 to 2 of the ambient levels of tritium measured in precipitation in several parts of Canada (approximately {<=}30 TU). (author)

  10. Surface wave site characterization at 27 locations near Boston, Massachusetts, including 2 strong-motion stations

    Science.gov (United States)

    Thompson, Eric M.; Carkin, Bradley A.; Baise, Laurie G.; Kayen, Robert E.

    2014-01-01

    microzonation map based on generalized velocity profiles, where the amplifications were computed using Shake (Schnable and others, 1972), along with an assumed input ground motion. The velocities were constrained by only a few local measurements associated with the Central Artery/Tunnel project. The additional VS measurements presented in this report provide a number of benefits. First, these measurements provide improved spatial coverage. Second, the larger sample size provides better constraints on the mean and variance of the VS distribution for each layer, which may be paired with a three-dimensional (3D) model of the stratigraphy to generate one-dimensional (1D) profiles for use in a standard site-response analysis (for example, Britton, 2003). Third, the velocity profiles may also be used, along with a 3D model of the stratigraphy, as input into a 3D simulation of the ground motion to investigate the effects of basin-generated surface waves and the potential focusing of seismic waves.This report begins with a short review of the geology of the study area and the field methods that we used to estimate the velocity profiles. The raw data, processed data, and the interpreted VS profiles are given in appendix 1. Photographs and descriptions of the sites are provided in appendix 2.

  11. Measurement and analysis of radiofrequency radiations from some mobile phone base stations in Ghana

    International Nuclear Information System (INIS)

    Amoako, J. K.; Fletcher, J. J.; Darko, E. O.

    2009-01-01

    A survey of the radiofrequency electromagnetic radiation at public access points in the vicinity of 50 cellular phone base stations has been carried out. The primary objective was to measure and analyse the electromagnetic field strength levels emitted by antennae installed and operated by the Ghana Telecommunications Company. On all the sites measurements were made using a hand-held spectrum analyser to determine the electric field level with the 900 and 1800 MHz frequency bands. The results indicated that power densities at public access points varied from as low as 0.01 μW m -2 to as high as 10 μW m -2 for the frequency of 900 MHz. At a transmission frequency of 1800 MHz, the variation of power densities is from 0.01 to 100 μW m -2 . The results were found to be in compliant with the International Commission on Non-ionizing Radiological Protection guidance level but were 20 times higher than the results generally obtained for such a practice elsewhere. There is therefore a need to re-assess the situation to ensure reduction in the present level as an increase in mobile phone usage is envisaged within the next few years. (authors)

  12. Measurement and analysis of radiofrequency radiations from some mobile phone base stations in Ghana.

    Science.gov (United States)

    Amoako, J K; Fletcher, J J; Darko, E O

    2009-08-01

    A survey of the radiofrequency electromagnetic radiation at public access points in the vicinity of 50 cellular phone base stations has been carried out. The primary objective was to measure and analyse the electromagnetic field strength levels emitted by antennae installed and operated by the Ghana Telecommunications Company. On all the sites measurements were made using a hand-held spectrum analyser to determine the electric field level with the 900 and 1800 MHz frequency bands. The results indicated that power densities at public access points varied from as low as 0.01 microW m(-2) to as high as 10 microW m(-2) for the frequency of 900 MHz. At a transmission frequency of 1800 MHz, the variation of power densities is from 0.01 to 100 microW m(-2). The results were found to be in compliant with the International Commission on Non-ionizing Radiological Protection guidance level but were 20 times higher than the results generally obtained for such a practice elsewhere. There is therefore a need to re-assess the situation to ensure reduction in the present level as an increase in mobile phone usage is envisaged within the next few years.

  13. Estimation of mean time to failure of a near surface radioactive waste repository for PWR power stations

    International Nuclear Information System (INIS)

    Aguiar, Lais A. de; Frutuoso e Melo, P.F.; Alvim, Antonio C.M.

    2007-01-01

    This work aims at estimating the mean time to failure (MTTF) of each barrier of a near surface radioactive waste repository. It is assumed that surface water infiltrates through the barriers, reaching the matrix where radionuclides are contained, releasing them to the environment. Radioactive wastes considered in this work are low and medium level wastes (produced during operation of a PWR nuclear power station) fixed on cement. The repository consists of 6 saturated porous media barriers (top cover, upper layer, packages, basis, repository walls and geosphere). It has been verified that the mean time to failure (MTTF) of each barrier increases for radionuclides having higher retardation factor (Fr) and also that the MTTF for concrete is larger for Nickel , while for the geosphere, Plutonium gives the largest MTTF. (author)

  14. “Sapsan”-carriages defrosting station of Nizhniy Novgorod railway service enterprise and its surface waste water purification

    Science.gov (United States)

    Strelkov, Alexander; Teplykh, Svetlana; Gorshkalev, Pavel; Bystranova, Anastasia

    2017-10-01

    Surface water disposal is one of the most relevant problems for Nizhniy Novgorod railway service enterprises. Waste water must be quickly removed with special drainage devices and water drainage facilities (culverts, slope drains, pipes, ditches, etc.). During “Sapsan”-carriages defrosting watse water is aggregated on railroad tracks. It leads to track bed structure sagging, roadbed washaway and damages to point switches. In this paper the authors describe a concrete system of waste water disposal from railway service enterprises. This system is realized through culverts readjusted at the foot of ballast section. Thereafter, the collected water is pumped into a water collector and to local sewage waste-disposal plants. For railway stations with three or more tracks surface runoff diversion scheme depends on topography, railway tracks types, flow discharge and is compiled individually for each object. This paper examines “Sapsan”-carriages defrosting station of Nizhniy Novgorod railway service enterprise. It presents a technology scheme and equipment consisting of Sand catcher LOS-P, Oil catcher LOS-N, pressure-tight flotation unit; drain feed pump; solution-consuming tank of the coagulant, the solution-consuming tank of flocculant. The proposed technology has been introduced into the project practice.

  15. Inspection of freeform surfaces considering uncertainties in measurement, localization and surface reconstruction

    International Nuclear Information System (INIS)

    Mehrad, Vahid; Xue, Deyi; Gu, Peihua

    2013-01-01

    Inspection of a manufactured freeform surface can be conducted by building its surface model and comparing this manufactured surface model with the ideal design surface model and its tolerance requirement. The manufactured freeform surface model is usually achieved by obtaining measurement points on the manufactured surface, transforming these measurement points from the measurement coordinate system to the design coordinate system through localization, and reconstructing the surface model using the localized measurement points. In this research, a method was developed to estimate the locations and their variances of any selected points on the reconstructed freeform surface considering different sources of uncertainties in measurement, localization and surface reconstruction processes. In this method, first locations and variances of the localized measurement points are calculated considering uncertainties of the measurement points and uncertainties introduced in the localization processes. Then locations and variances of points on the reconstructed freeform surface are obtained considering uncertainties of the localized measurement points and uncertainties introduced in the freeform surface reconstruction process. Two case studies were developed to demonstrate how these three different uncertainty sources influence the quality of the reconstructed freeform curve and freeform surface in inspection. (paper)

  16. Seasonal signatures in SFG vibrational spectra of the sea surface nanolayer at Boknis Eck Time Series Station (SW Baltic Sea

    Directory of Open Access Journals (Sweden)

    K. Laß

    2013-08-01

    Full Text Available The very thin sea surface nanolayer on top of the sea surface microlayer, sometimes just one monomolecular layer thick, forms the interface between ocean and atmosphere. Due to the small dimension and tiny amount of substance, knowledge about the development of the layer in the course of the year is scarce. In this work, the sea surface nanolayer at Boknis Eck Time Series Station (BE, southwestern Baltic Sea, has been investigated over a period of three and a half years. Surface water samples were taken monthly by screen sampling and were analyzed in terms of organic content and composition by sum frequency generation spectroscopy, which is specifically sensitive to interfacial layers. A yearly periodicity has been observed with a pronounced abundance of sea surface nanolayer material (such as carbohydrate-rich material during the summer months. On the basis of our results we conclude that the abundance of organic material in the nanolayer at Boknis Eck is not directly related to phytoplankton abundance alone. We speculate that indeed sloppy feeding of zooplankton together with photochemical and/or microbial processing of organic precursor compounds is responsible for the pronounced seasonality.

  17. Seasonal signatures in SFG vibrational spectra of the sea surface nanolayer at Boknis Eck Time Series Station (SW Baltic Sea)

    Science.gov (United States)

    Laß, K.; Bange, H. W.; Friedrichs, G.

    2013-08-01

    The very thin sea surface nanolayer on top of the sea surface microlayer, sometimes just one monomolecular layer thick, forms the interface between ocean and atmosphere. Due to the small dimension and tiny amount of substance, knowledge about the development of the layer in the course of the year is scarce. In this work, the sea surface nanolayer at Boknis Eck Time Series Station (BE), southwestern Baltic Sea, has been investigated over a period of three and a half years. Surface water samples were taken monthly by screen sampling and were analyzed in terms of organic content and composition by sum frequency generation spectroscopy, which is specifically sensitive to interfacial layers. A yearly periodicity has been observed with a pronounced abundance of sea surface nanolayer material (such as carbohydrate-rich material) during the summer months. On the basis of our results we conclude that the abundance of organic material in the nanolayer at Boknis Eck is not directly related to phytoplankton abundance alone. We speculate that indeed sloppy feeding of zooplankton together with photochemical and/or microbial processing of organic precursor compounds is responsible for the pronounced seasonality.

  18. Constructing Invariant Fairness Measures for Surfaces

    DEFF Research Database (Denmark)

    Gravesen, Jens; Ungstrup, Michael

    1998-01-01

    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...

  19. Surface magnetic field measurement with magnetic shielding

    Czech Academy of Sciences Publication Activity Database

    Perevertov, Oleksiy

    2010-01-01

    Roč. 61, č. 7 (2010), 66-68 ISSN 1335-3632 Grant - others:AVČR(CZ) M100100906 Institutional research plan: CEZ:AV0Z10100520 Keywords : magnetic hysteresis * magnetic field measurement * magnetic shielding * extrapolation Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.270, year: 2010

  20. Hydrogeology of Melton Valley determined from hydraulic head measuring station data

    International Nuclear Information System (INIS)

    Dreier, R.B.; Toran, L.E.

    1989-06-01

    The hydraulic head measuring stations (HHMSs) are well clusters that provide data required for evaluating both the transition between shallow and deep groundwater system(s) and the nature of the deep system(s). This information can be used to aid the characterization of the local hydrologic framework as dictated by state and federal regulatory agencies. Specifically this project provides a means for defining the lower boundary of the uppermost aquifer and for identifying potential pathways for off-site contaminant migration for shallow, intermediate, and deep groundwater flow. In addition, this project provides some of the geologic and hydrologic background information required to perform a risk assessment for individual waste sites. The objectives of the HHMS general plant projects are threefold: (1) to characterize potentiometric head levels in and near waste management areas in Melton Valley, (2) to characterize the geology in Melton Valley, and (3) to determine groundwater quality at their respective locations. This report presents results of data collected from wells constructed in FY 1986 and FY 1988. To meet these objectives, each HHMS was designed to consist of three telescoping wells, approximately 25 ft apart. The deepest well was drilled to approximately 400 ft, and the intermediate and shallow wells are approximately 200 and 80 ft deep, respectively. The open interval extends at least 20 ft below the bottom of the cased section of each well. 25 refs., 25 figs., 8 tabs

  1. Trends in surface-water quality at selected National Stream Quality Accounting Network (NASQAN) stations, in Michigan

    Science.gov (United States)

    Syed, Atiq U.; Fogarty, Lisa R.

    2005-01-01

    -treatment processes, and effective regulations. Phosphorus data for most of the study stations could not be analyzed because of the data limitations for trend tests. The only station with a significant negative trend in total phosphorus concentration is the Clinton River at Mount Clemens. However, scatter-plot analyses of phosphorus data indicate decreasing concentrations with time for most of the study stations. Positive trends in concentration of nitrogen compounds were detected at the Kalamazoo River near Saugatuck and Muskegon River near Bridgeton. Positive trends in both fecal coliform and total fecal coliform were detected at the Tahquamenon River near Paradise. Various different point and nonpoint sources could produce such positive trends, but most commonly the increase in concentrations of nitrogen compounds and fecal coliform bacteria are associated with agricultural practices and sewage-plant discharges. The constituent with the most numerous and geographically widespread significant trend is pH. The pH levels increased at six out of nine stations on all the major rivers in Michigan, with no negative trend at any station. The cause of pH increase is difficult to determine, as it could be related to a combination of anthropogenic activities and natural processes occurring simultaneously in the environment. Trends in concentration of major ions, such as calcium, sodium, magnesium, sulfate, fluoride, chloride, and potassium, were detected at eight out of nine stations. A negative trend was detected only in sulfate and fluoride concentrations; a positive trend was detected only in calcium concentration. The major ions with the most widespread significant trends are sodium and chloride; three positive and two negative trends were detected for sodium, and three negative and two positive trends were detected for chloride. The negative trends in chloride concentrations outnumbered the positive trends. This result indicates a slight improvement in surface-water quality because

  2. Seasonal features of atmospheric surface-layer characteristics over a tropical coastal station in Southern India

    International Nuclear Information System (INIS)

    Hari Prasad, K.B.R.R.; Srinivas, C.V.; Baskaran, R.; Venkatraman, B.

    2016-01-01

    Dispersion of air-borne effluents occurs in the atmospheric boundary layer (ABL) where turbulence is the main physical processes. In the surface layer of ABL, the mechanical (shear) generation of turbulence exceeds the buoyant generation or consumption of turbulence. In this layer, under steady state and horizontally homogeneous conditions various forces in the governing equation can be neglected and one can apply Monin-Obukhov Similarity Theory (MOST) to estimate the turbulent fluxes and other surface layer variables. Understanding the turbulent characteristics of the surface layer is vital for modeling of turbulent diffusion in regional numerical weather and pollution dispersion models. The objective of this study is to verify the validity of the MOST at the coastal site Kalpakkam under various atmospheric stability conditions with respect to different seasons for modeling atmospheric dispersion of radioactive effluents

  3. 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...

  4. Grain size measurements by ultrasonic Rayleigh surface waves

    International Nuclear Information System (INIS)

    Palanichamy, P.; Jayakumar, T.

    1996-01-01

    The use of Rayleigh surface waves to determine average grain size nondestructively in an austenitic stainless steel AISI type 316 stainless is discussed. Two commercial type 4MHz frequency surface wave transducers, one as transmitter and the other as receiver were employed for the measurement of surface wave amplitudes. Relative amplitudes of the Rayleigh surface waves were correlated with the metallographically obtained grain sizes. Results indicate that surface/sub-surface average grain sizes of AISI type 316 austenitic stainless steel can be estimated with a confidence level of more than 80% in the grain size range 30-170 μm. (author)

  5. In situ surface roughness measurement using a laser scattering method

    Science.gov (United States)

    Tay, C. J.; Wang, S. H.; Quan, C.; Shang, H. M.

    2003-03-01

    In this paper, the design and development of an optical probe for in situ measurement of surface roughness are discussed. Based on this light scattering principle, the probe which consists of a laser diode, measuring lens and a linear photodiode array, is designed to capture the scattered light from a test surface with a relatively large scattering angle ϕ (=28°). This capability increases the measuring range and enhances repeatability of the results. The coaxial arrangement that incorporates a dual-laser beam and a constant compressed air stream renders the proposed system insensitive to movement or vibration of the test surface as well as surface conditions. Tests were conducted on workpieces which were mounted on a turning machine that operates with different cutting speeds. Test specimens which underwent different machining processes and of different surface finish were also studied. The results obtained demonstrate the feasibility of surface roughness measurement using the proposed method.

  6. Analysis of intensive aerosol optical properties measured at the Jungfraujoch station

    Energy Technology Data Exchange (ETDEWEB)

    Li, F.; Nyeki, S.; Baltensperger, U.; Weingartner, E.; Lugauer, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    Characterisation of atmospheric aerosol optical properties at the Jungfraujoch has been conducted to deliver basic data for comparison with those from NOAA baseline atmospheric monitoring stations. (author) 2 figs., 2 refs.

  7. Passive seismic experiment - A summary of current status. [Apollo-initiated lunar surface station data

    Science.gov (United States)

    Latham, G. V.; Dorman, H. J.; Horvath, P.; Ibrahim, A. K.; Koyama, J.; Nakamura, Y.

    1978-01-01

    The data set obtained from the four-station Apollo seismic network including signals from approximately 11,800 events, is surveyed. Some refinement of the lunar model will result, but its gross features remain the same. Attention is given to the question of a small, molten lunar core, the answer to which remains dependent on analysis of signals from a far side impact. Seventy three sources of repeating, deep moonquakes have been identified, thirty nine of which have been accurately located. Concentrated at depths from 800 to 1000 km, the periodicities of these events have led to the hypothesis that they are generated by tidal stresses. Lunar seismic data has also indicated that the meteoroid population is ten times lower than originally determined from earth based observations. Lunar seismic activity is much lower and mountainous masses show no sign of sinking, in contrast to earth, as a result of the lunar crust being four times thicker. While much work remains to be done, significant correlation between terrestrial and lunar observations can be seen.

  8. Sorption (Kd) measurements in support of dose assessments for Zion Nuclear Station Decommissioning

    Energy Technology Data Exchange (ETDEWEB)

    Yim S. P.; Sullivan T.; Milian, L.

    2012-12-12

    The Zion Nuclear Power Station is being decommissioned. ZionSolutions proposes to leave much of the below grade structures in place and to fill them with “clean” concrete demolition debris from the above grade parts of the facility. This study, commissioned by ZionSolutions and conducted by the Brookhaven National Laboratory (BNL) was performed to provide site-specific data for performance assessment calculations to support the request to terminate the NRC license and allow unrestricted use of the facility. Specifically, this study measured the distribution coefficient for five radionuclides of concern using site-specific soils and groundwater. The distributions coefficient is a measure of the amount of the radionuclide that will remain sorbed to the soil or concrete that is present relative to the amount that will remain in solution. A high distribution coefficient indicates most of the radionuclide will remain on the solid material and will not be available for transport by the groundwater. The radionuclides of concern are Fe-55, Co-60, Ni-63, Sr-90, and Cs-137. Tests were performed following ASTM C1733-10, Standard Test Methods for Distribution Coefficients of Inorganic Species by the Batch Method. Sr-85 was used in the testing as an analogue for Sr-90 because it behaves similarly with respect to sorption and has a gamma emission that is easier to detect than the beta emission from Sr-90. Site-specific soils included disturbed sand (sand removed during construction and used as backfill), native sand, silt/clay and silt. In addition, concrete cores from the Unit-1 Containment Building and the Crib House were broken into particles less than 2 mm in size and tested to obtain distribution coefficients for the five nuclides.

  9. Diversity of bacterioplankton in the surface seawaters of Drake Passage near the Chinese Antarctic station.

    Science.gov (United States)

    Xing, Mengxin; Li, Zhao; Wang, Wei; Sun, Mi

    2015-07-01

    The determination of relative abundances and distribution of different bacterial groups is a critical step toward understanding the functions of various bacteria and its surrounding environment. Few studies focus on the taxonomic composition and functional diversity of microbial communities in Drake Passage. In this study, marine bacterioplankton communities from surface seawaters at five locations in Drake Passage were examined by 16S rRNA gene sequence analyses. The results indicated that psychrophilic bacteria were the most abundant group in Drake Passage, and mainly made up of Bacillus, Aeromonas, Psychrobacter, Pseudomonas and Halomonas. Diversity analysis showed that surface seawater communities had no significant correlation with latitudinal gradient. Additionally, a clear difference among five surface seawater communities was evident, with 1.8% OTUs (only two) belonged to Bacillus consistent across five locations and 71% OTUs (80) existed in only one location. However, the few cosmopolitans had the largest population sizes. Our results support the hypothesis that the dominant bacterial groups appear to be analogous between geographical sites, but significant differences may be detected among rare bacterial groups. The microbial diversity of surface seawaters would be liable to be affected by environmental factors. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Variations of surface temparature with solar activity at two stations in ...

    African Journals Online (AJOL)

    Nigeria Journal of Pure and Applied Physics ... A consistent and persistent diurnal variation in surface air temperature exists which shows an almost constant level in the early morning hours (0000 0600 hours LT.); a rise at sunrise till about 1500 hr LT., a subsequent fall to the constant level by about 1900 hr LT. at sunset.

  11. Photovoltaic Engineering Testbed: A Facility for Space Calibration and Measurement of Solar Cells on the International Space Station

    Science.gov (United States)

    Landis, Geoffrey A.; Bailey, Sheila G.; Jenkins, Phillip; Sexton, J. Andrew; Scheiman, David; Christie, Robert; Charpie, James; Gerber, Scott S.; Johnson, D. Bruce

    2001-01-01

    The Photovoltaic Engineering Testbed ("PET") is a facility to be flown on the International Space Station to perform calibration, measurement, and qualification of solar cells in the space environment and then returning the cells to Earth for laboratory use. PET will allow rapid turnaround testing of new photovoltaic technology under AM0 conditions.

  12. 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

  13. Seafloor geodesy: Measuring surface deformation and strain-build up

    Science.gov (United States)

    Kopp, Heidrun; Lange, Dietrich; Hannemann, Katrin; Petersen, Florian

    2017-04-01

    Seafloor deformation is intrinsically related to tectonic processes, which potentially may evolve into geohazards, including earthquakes and tsunamis. The nascent scientific field of seafloor geodesy provides a way to monitor crustal deformation at high resolution comparable to the satellite-based GPS technique upon which terrestrial geodesy is largely based. The measurements extract information on stress and elastic strain stored in the oceanic crust. Horizontal seafloor displacement can be obtained by acoustic/GPS combination to provide absolute positioning or by long-term acoustic telemetry between different beacons fixed on the seafloor. The GeoSEA (Geodetic Earthquake Observatory on the SEAfloor) array uses acoustic telemetry for relative positioning at mm-scale resolution. The transponders within an array intercommunicate via acoustic signals for a period of up to 3.5 years. The seafloor acoustic transponders are mounted on 4 m high tripod steel frames to ensure clear line-of-sight between the stations. The transponders also include high-precision pressure sensors to monitor vertical movements and dual-axis inclinometers in order to measure their level as well as any tilt of the seafloor. Sound velocity sensor measurements are used to correct for water sound speed variations. A further component of the network is GeoSURF, a self-steering autonomous surface vehicle (Wave Glider), which monitors system health and is able to upload the seafloor data to the sea surface and to transfer it via satellite. The GeoSEA array is capable of both continuously monitoring horizontal and vertical ground displacement rates along submarine fault zones and characterizing their behavior (locked or aseismically creeping). Seafloor transponders are currently installed along the Siliviri segment of the North Anatolian Fault offshore Istanbul for measurements of strain build-up along the fault. The first 18 month of baseline ranging were analyzed by a joint-least square inversion

  14. 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.

  15. Corrosion of circulating water pipings in thermal and nuclear power stations and corrosion prevention measures

    International Nuclear Information System (INIS)

    Hachiya, Minoru

    1982-01-01

    In the age of energy conservation at present, the power generation facilities have been examined from the viewpoint of performance, endurance and economy, and in particular, the prevention of the loss due to the corrosion of various facilities is one of most important problems. Since circulating water pipings are in contact with sea water and soil, the peculiar corrosion phenomena are brought about on their external and internal surfaces. Namely, the pitting corrosion due to the environment of soil quality difference, the defects of coating and the contact with reinforcing bars in concrete occurs on the external surface, and the overall corrosion due to the increase of flow velocity and the pitting corrosion due to the defects of coating, the contact with different kinds of metals and the gap in corrosion-resistant steel occur on the internal surface. As the measures for corrosion prevention, corrosion-preventive coating and electric corrosion prevention are applied. The principle, the potential and current density, the system, the design procedure and the examples of application of electric corrosion prevention are described. (Kako, I.)

  16. Halogenated source gases measured by FTIR at the Jungfraujoch station: updated trends and new target species

    Science.gov (United States)

    Mahieu, Emmanuel; Bader, Whitney; Bovy, Benoît; Franco, Bruno; Lejeune, Bernard; Servais, Christian; Notholt, Justus; Palm, Mathias; Toon, Geoffrey C.

    2015-04-01

    retrieve additional halogenated source gases from FTIR spectra will also be evoked. Our trend results will be critically discussed and compared with measurements performed in the northern hemisphere by the in situ networks. Acknowledgments The University of Liège contribution to the present work has primarily been supported by the AGACC-II project of the SSD program funded by the Belgian Federal Science Policy Office (BELSPO), Brussels. E. Mahieu is Research Associate with the F.R.S. - FNRS. Laboratory developments and mission expenses at the Jungfraujoch station were funded by the F.R.S. - FNRS and the Fédération Wallonie-Bruxelles, respectively. We thank the International Foundation High Altitude Research Stations Jungfraujoch and Gornergrat (HFSJG, Bern) for supporting the facilities needed to perform the observations. We further acknowledge the vital contribution from all the Belgian colleagues in performing the Jungfraujoch observations used here. References Mahieu, E., S. O'Doherty, S. Reimann, et al., First retrievals of HCFC-142b from ground-based high-resolution FTIR solar observations: application to high-altitude Jungfraujoch spectra, poster presentation at the 'EGU 2013 General Assembly', 07-12 April 2013, Vienna, Austria, 2013. [http://hdl.handle.net/2268/144709] Mahieu, E., M.P. Chipperfield, J. Notholt, et al., Recent Northern Hemisphere stratospheric HCl increase due to atmospheric circulation changes, Nature, 515, 104-107, doi:10.1038/nature13857, 2014a. Mahieu, E., R. Zander, G.C. Toon, et al., Spectrometric monitoring of atmospheric carbon tetrafluoride (CF4) above the Jungfraujoch station since 1989: evidence of continued increase but at a slowing rate, Atmos. Meas. Tech., 7, 333-344, 2014b. [http://hdl.handle.net/2268/154767] Montzka, S.A., S. Reimann, A. Engel, et al., Ozone-Depleting Substances (ODSs) and Related Chemicals, Chapter 1 in Scientific Assessment of Ozone Depletion: 2010, Global Ozone Research and Monitoring Project-Report No. 52, 516

  17. 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.

  18. Contaminations of inner surface of magnesium fluoride windows in the `Expose-R' experiment on the International Space Station

    Science.gov (United States)

    Skurat, V. E.

    2017-10-01

    A series of experiments was carried out previously on board of the International Space Station in `EXPOSE-R', a multi-user expose facility, provided by European Space Agency attached to the external surface of the Russian Segment. In one experiment, spores of microorganisms and species of higher plant seeds, in heat-sealed polymer bags were irradiated by solar radiation passed through MgF2 windows in a high space vacuum. After sample exposure, it was found that in many cases the inner surfaces of windows were contaminated. Analysis of the contamination revealed the presence of chemical groups CH2, CH3, NH, OH, C═O, Si-CH3 (Demets et al. in 2015). Their presence in deposits was explained by photofixation of gaseous precursors - some of the vapours of glues and additives in polymeric materials in the core facility of `Expose-R'. Carbon-, oxygen- and silicon-containing groups may be deposited from outer intrinsic atmosphere. This atmosphere is connected with sample compartments and core facility. However, the presence of NH groups on inner surfaces of windows was not expected. This paper shows that the process responsible for carbon-, nitrogen- and oxygen-containing group formation can be a photopolymerization of caprolactam, which is released from the outer Nylon 6 layer of polymer bags under Solar vacuum ultraviolet radiation.

  19. Coherent lidar wind measurements from the Space Station base using 1.5 m all-reflective optics

    Science.gov (United States)

    Bilbro, J. W.; Beranek, R. G.

    1987-01-01

    This paper discusses the space-based measurement of atmospheric winds from the point of view of the requirements of the optical system of a coherent CO2 lidar. A brief description of the measurement technique is given and a discussion of previous study results provided. The telescope requirements for a Space Station based lidar are arrived at through discussions of the desired system sensitivity and the need for lag angle compensation.

  20. Evaluation of Multi-Year Continuous Measurements of Ultrafine Particles at Two Near-Road Stations in Toronto, Canada

    Science.gov (United States)

    Su, Y.; Sofowote, U.; Debosz, J.; Munoz, T.; Whitelaw, C.

    2013-12-01

    Particles with an aerodynamic diameter less than 100 nanometre (nm) are referred to as ultrafine particles (UFPs). Relative to fine and course particles, UFPs have greater potential to be suspended in air for a longer time and absorb toxic chemicals due to their larger surface areas per unit mass. UFPs could penetrate deep into the respiratory or cardiovascular systems and pose adverse health effects. In urban environments, primary sources of UFPs are from road traffic emissions and account for most of the total particle numbers. Controls on UPFs rely on better understanding of their emission sources and environmental behaviour. Ontario Ministry of the Environment have monitored UFPs since 2010 at two near-road stations in Toronto by using TSI 3031 UFP monitors. The two monitoring stations are approximately 20-30 meters adjacent to major arterial roads with over 20,000 vehicles per day. UFPs concentrations were monitored using six size channels: 20-30nm, 30-50nm, 50-70nm, 70-100nm, 100-200nm, and 200-450nm. Data are collected at time intervals of 11 or 15 minutes and averaged hourly. Concurrent measurements include wind speeds, wind directions, and concentrations of other air pollutants such as nitrogen oxides and black carbon. Data influenced by road-side traffic emissions were filtered by wind direction within 45° of normal to the road and wind speed greater than 1 m/s. Number concentrations were found higher for particles with sizes of 20-30nm and 30-50nm than for other sizes of UFPs. The observed particle number distributions are generally consistent with the theoretical understanding of particle nuclei mode and accumulation mode. During the day, for UFPs with sizes of 20-30nm and 30-50nm, elevated number concentrations were observed in morning traffic hours and to a less extent in the late afternoon. The elevated UFPs number concentrations coincided with nitrogen oxides and black carbon. Moreover, higher number concentrations were found on weekdays than

  1. Measurements of radon progeny activity on typical indoor surfaces

    International Nuclear Information System (INIS)

    Knutson, E.O.; Gogolak, C.V.; Klemic, G.

    1992-01-01

    A number of studies aimed at defining how well radon progeny on surfaces can be measured, information that is needed in order to test physical/mathematical models governing indoor radon progeny behaviour, are described. One experiment compared the decomposition on to different surfaces. Only relatively small differences were found among metal, filter paper, broadcloth, corduroy fabric, vinyl wallpaper, glass, and latex paint, but polyethylene film collected two to four times as much as the others, due most likely to electrostatic charge on the plastic surface. Another experiment compared the gamma and gross alpha count methods of measuring surface activity for metal, filter paper, broadcloth and corduroy surfaces. No difference for the surfaces tested was found from which it is concluded that, even for rougher surfaces, progeny atoms deposit mainly on the outer layers. A final experiment compared in situ and surrogate-surface methods for measuring surface deposition. For most tests, the two methods agreed within 30%, and the average ratio was not significantly different from unity. 210 Po is a complication in the in situ method. An unexpected location effect was found in the experiments conducted in houses with high radon concentrations: the deposition on the ceiling was higher than on the surfaces. (author)

  2. Direct Measurement of the Surface Energy of Graphene.

    Science.gov (United States)

    van Engers, Christian D; Cousens, Nico E A; Babenko, Vitaliy; Britton, Jude; Zappone, Bruno; Grobert, Nicole; Perkin, Susan

    2017-06-14

    Graphene produced by chemical vapor deposition (CVD) is a promising candidate for implementing graphene in a range of technologies. In most device configurations, one side of the graphene is supported by a solid substrate, wheras the other side is in contact with a medium of interest, such as a liquid or other two-dimensional material within a van der Waals stack. In such devices, graphene interacts on both faces via noncovalent interactions and therefore surface energies are key parameters for device fabrication and operation. In this work, we directly measured adhesive forces and surface energies of CVD-grown graphene in dry nitrogen, water, and sodium cholate using a modified surface force balance. For this, we fabricated large (∼1 cm 2 ) and clean graphene-coated surfaces with smooth topography at both macro- and nanoscales. By bringing two such surfaces into contact and measuring the force required to separate them, we measured the surface energy of single-layer graphene in dry nitrogen to be 115 ± 4 mJ/m 2 , which was similar to that of few-layer graphene (119 ± 3 mJ/m 2 ). In water and sodium cholate, we measured interfacial energies of 83 ± 7 and 29 ± 6 mJ/m 2 , respectively. Our work provides the first direct measurement of graphene surface energy and is expected to have an impact both on the development of graphene-based devices and contribute to the fundamental understanding of surface interactions.

  3. An intercomparison of surface energy flux measurement systems used during FIFE 1987

    International Nuclear Information System (INIS)

    Nie, D.; Kanemasu, E.T.; Fritschen, L.J.; Weaver, H.L.; Smith, E.A.; Verma, S.B.; Field, R.T.; Kustas, W.P.; Stewart, J.B.

    1992-01-01

    During FIFE 1987, surface energy fluxes were measured at 22 flux sites by nine groups of scientists using different measuring systems. A rover Bowen ratio station was taken to 20 of the flux stations to serve as a reference for estimating the instrument-related differences. The rover system was installed within a few meters from the host instrument of a site. Using linear regression analysis, net radiation, Bowen ratio, and latent heat fluxes were compared between the rover measurements and the host measurements. The average differences in net radiation, Bowen ratio, and latent heat flux from different types of instruments can be up to 10, 30, and 20 percent, respectively. The Didcot net radiometer gave higher net radiation while the Swissteco type showed lower values, as compared to the corrected radiation energy balance system (REBS) model. The four-way components method and the Thornthwaite type give similar values to the REBS. The surface energy radiation balance systems type Bowen ratio systems exhibit slightly lower Bowen ratios and thus higher latent heat fluxes, compared to the arid zone evapotranspiration systems. Eddy correlation systems showed slightly lower latent heat flux in comparison to the Bowen ratio systems. It is recommended that users of the flux data take these differences into account. 11 refs

  4. 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

  5. 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

  6. 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

  7. 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

  8. Monitoring surface-water quality in Arizona: the fixed-station network

    Science.gov (United States)

    Tadayon, Saeid

    2000-01-01

    Arizona is an arid State in which economic development is influenced largely by the quantity and quality of water and the location of adequate water supplies. In 1995, surface water supplied about 58 percent of total withdrawals in Arizona. Of the total amount of surface water used in 1995, about 89 percent was for agriculture, 10 percent for public supply, and 1 percent for industrial supply (including mining and thermoelectric; Solley and others, 1998). As a result of rapid population growth in Arizona, historic agricultural lands in the Phoenix (Maricopa County) and Tucson (Pima County) areas are now being developed for residential and commercial use; thus, the amount of water used for public supply is increasing. The Clean Water Act was established by U.S. Congress (1972) in response to public concern about water-pollution control. The act defines a process by which the United States Congress and the citizens are informed of the Nation’s progress in restoring and maintaining the quality of our waters. The Arizona Department of Environmental Quality (ADEQ) is the State-designated agency for this process and, as a result, has developed a monitoring program to assess water quality in Arizona. The ADEQ is required to submit a water-quality assessment report to the United States Environmental Protection Agency (USEPA) every 2 years. The USEPA summarizes the reports from each State and submits a report to the Congress characterizing water quality in the United States. These reports serve to inform Congress and the public of the Nation’s progress toward the restoration and maintenance of water quality in the United States (Arizona Department of Environmental Quality, 1998).

  9. Statistical analysis of electromagnetic radiation measurements in the vicinity of GSM/UMTS base station installed on buildings in Serbia.

    Science.gov (United States)

    Koprivica, Mladen; Slavkovic, Vladimir; Neskovic, Natasa; Neskovic, Aleksandar

    2016-03-01

    As a result of dense deployment of public mobile base stations, additional electromagnetic (EM) radiation occurs in the modern human environment. At the same time, public concern about the exposure to EM radiation emitted by such sources has increased. In order to determine the level of radio frequency radiation generated by base stations, extensive EM field strength measurements were carried out for 664 base station locations, from which 276 locations refer to the case of base stations with antenna system installed on buildings. Having in mind the large percentage (42 %) of locations with installations on buildings, as well as the inevitable presence of people in their vicinity, a detailed analysis of this location category was performed. Measurement results showed that the maximum recorded value of total electric field strength has exceeded International Commission on Non-Ionizing Radiation Protection general public exposure reference levels at 2.5 % of locations and Serbian national reference levels at 15.6 % of locations. It should be emphasised that the values exceeding the reference levels were observed only outdoor, while in indoor total electric field strength in no case exceeded the defined reference levels. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Statistical analysis of electromagnetic radiation measurements in the vicinity of GSM/UMTS base station installed on buildings in Serbia

    International Nuclear Information System (INIS)

    Koprivica, Mladen; Slavkovic, Vladimir; Neskovic, Natasa; Neskovic, Aleksandar

    2016-01-01

    As a result of dense deployment of public mobile base stations, additional electromagnetic (EM) radiation occurs in the modern human environment. At the same time, public concern about the exposure to EM radiation emitted by such sources has increased. In order to determine the level of radio frequency radiation generated by base stations, extensive EM field strength measurements were carried out for 664 base station locations, from which 276 locations refer to the case of base stations with antenna system installed on buildings. Having in mind the large percentage (42 %) of locations with installations on buildings, as well as the inevitable presence of people in their vicinity, a detailed analysis of this location category was performed. Measurement results showed that the maximum recorded value of total electric field strength has exceeded International Commission on Non-Ionizing Radiation Protection general public exposure reference levels at 2.5 % of locations and Serbian national reference levels at 15.6 % of locations. It should be emphasised that the values exceeding the reference levels were observed only outdoor, while in indoor total electric field strength in no case exceeded the defined reference levels. (authors)

  11. 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

  12. Shear wave velocity model beneath CBJI station West Java, Indonesia from joint inversion of teleseismic receiver functions and surface wave dispersion

    Science.gov (United States)

    Simanungkalit, R. H.; Anggono, T.; Syuhada; Amran, A.; Supriyanto

    2018-03-01

    Earthquake signal observations around the world allow seismologists to obtain the information of internal structure of the Earth especially the Earth’s crust. In this study, we used joint inversion of receiver functions and surface wave group velocities to investigate crustal structure beneath CBJI station in West Java, Indonesia. Receiver function were calculated from earthquakes with magnitude more than 5 and at distance 30°-90°. Surface wave group velocities were calculated using frequency time analysis from earthquakes at distance of 30°- 40°. We inverted shear wave velocity model beneath the station by conducting joint inversion from receiver functions and surface wave dispersions. We suggest that the crustal thickness beneath CBJI station, West Java, Indonesia is about 35 km.

  13. 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

  14. 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...

  15. 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.

  16. Simulated BRDF based on measured surface topography of metal

    Science.gov (United States)

    Yang, Haiyue; Haist, Tobias; Gronle, Marc; Osten, Wolfgang

    2017-06-01

    The radiative reflective properties of a calibration standard rough surface were simulated by ray tracing and the Finite-difference time-domain (FDTD) method. The simulation results have been used to compute the reflectance distribution functions (BRDF) of metal surfaces and have been compared with experimental measurements. The experimental and simulated results are in good agreement.

  17. Measurement of grassland evaporation using a surface-layer ...

    African Journals Online (AJOL)

    Measurement of grassland evaporation using a surface-layer scintillometer. ... Water SA. Journal Home · ABOUT THIS JOURNAL · Advanced Search ... of soil heat flux and net irradiance, evaporation rates were calculated as a residual of the ...

  18. Calibration technique for the neutron surface moisture measurement system

    International Nuclear Information System (INIS)

    Watson, W.T.; Shreve, D.C.

    1996-01-01

    A technique for calibrating the response of a surface neutron moisture measurement probe to material moisture concentration has been devised. Tests to ensure that the probe will function in the expected in-tank operating environment are also outlined

  19. Methods and strategy for modeling daily global solar radiation with measured meteorological data - A case study in Nanchang station, China

    International Nuclear Information System (INIS)

    Wu, Guofeng; Liu, Yaolin; Wang, Tiejun

    2007-01-01

    Solar radiation is a primary driver for many physical, chemical and biological processes on the earth's surface, and complete and accurate solar radiation data at a specific region are quite indispensable to the solar energy related researches. This study, with Nanchang station, China, as a case study, aimed to calibrate existing models and develop new models for estimating missing global solar radiation data using commonly measured meteorological data and to propose a strategy for selecting the optimal models under different situations of available meteorological data. Using daily global radiation, sunshine hours, temperature, total precipitation and dew point data covering the years from 1994 to 2005, we calibrated or developed and evaluated seven existing models and two new models. Validation criteria included intercept, slope, coefficient of determination, mean bias error and root mean square error. The best result (R 2 = 0.93) was derived from Chen model 2, which uses sunshine hours and temperature as predictors. The Bahel model, which only uses sunshine hours, was almost as good, explaining 92% of the solar radiation variance. Temperature based models (Bristow and Campbell, Allen, Hargreaves and Chen 1 models) provided less accurate results, of which the best one (R 2 = 0.69) is the Bristow and Campbell model. The temperature based models were improved by adding other variables (daily mean total precipitation and mean dew point). Two such models could explain 77% (Wu model 1) and 80% (Wu model 2) of the solar radiation variance. We, thus, propose a strategy for selecting an optimal method for calculating missing daily values of global solar radiation: (1) when sunshine hour and temperature data are available, use Chen model 2; (2) when only sunshine hour data are available, use Bahel model; (3) when temperature, total precipitation and dew point data are available but not sunshine hours, use Wu model 2; (4) when only temperature and total precipitation are

  20. Surface Resistance Measurements of LHC Dipole Beam Screen Samples

    CERN Document Server

    Caspers, Friedhelm; Ruggiero, F; Tan, J; Tsutsui, H

    2000-01-01

    An estimate of the resistive losses in the LHC dipole beam screen is given from cold surface resistance measurements using the shielded pair technique. Several beam screen samples have been evaluated, with different copper coating methods, including a sample with ribbed surface envisaged to reduce electron cloud losses thanks to its low reflectivity. Experimental data, derived by a proper analysis of the measured Q-factors and including error estimates are compared with theoretical predictions of the anomalous skin effect.

  1. On $L_p$ Affine Surface Area and Curvature Measures

    OpenAIRE

    Zhao, Yiming

    2015-01-01

    The relationship between $L_p$ affine surface area and curvature measures is investigated. As a result, a new representation of the existing notion of $L_p$ affine surface area depending only on curvature measures is derived. Direct proofs of the equivalence between this new representation and those previously known are provided. The proofs show that the new representation is, in a sense, "polar" to that of Lutwak's and "dual" to that of Sch\\"utt & Werner's.

  2. Improvements to a Response Surface Thermal Model for Orion Mated to the International Space Station

    Science.gov (United States)

    Miller, StephenW.; Walker, William Q.

    2011-01-01

    This study is an extension of previous work to evaluate the applicability of Design of Experiments (DOE)/Response Surface Methodology to on-orbit thermal analysis. The goal was to determine if the methodology could produce a Response Surface Equation (RSE) that predicted the thermal model temperature results within +/-10 F. An RSE is a polynomial expression that can then be used to predict temperatures for a defined range of factor combinations. Based on suggestions received from the previous work, this study used a model with simpler geometry, considered polynomials up to fifth order, and evaluated orbital temperature variations to establish a minimum and maximum temperature for each component. A simplified Outer Mold Line (OML) thermal model of the Orion spacecraft was used in this study. The factors chosen were the vehicle's Yaw, Pitch, and Roll (defining the on-orbit attitude), the Beta angle (restricted to positive beta angles from 0 to 75), and the environmental constants (varying from cold to hot). All factors were normalized from their native ranges to a non-dimensional range from -1.0 to 1.0. Twenty-three components from the OML were chosen and the minimum and maximum orbital temperatures were calculated for each to produce forty-six responses for the DOE model. A customized DOE case matrix of 145 analysis cases was developed which used analysis points at the factor corners, mid-points, and center. From this data set, RSE s were developed which consisted of cubic, quartic, and fifth order polynomials. The results presented are for the fifth order RSE. The RSE results were then evaluated for agreement with the analytical model predictions to produce a +/-3(sigma) error band. Forty of the 46 responses had a +/-3(sigma) value of 10 F or less. Encouraged by this initial success, two additional sets of verification cases were selected. One contained 20 cases, the other 50 cases. These cases were evaluated both with the fifth order RSE and with the analytical

  3. Water shortage and drought monitoring in Bačka region (Vojvodina, North Serbia: Setting-up measurement stations network

    Directory of Open Access Journals (Sweden)

    Jovanović Mlađen

    2013-01-01

    Full Text Available Water shortage and drought, as the most important hydro-climatic hazards, cause significant damages in case of most continents including SE Europe. An experimental field established in Bačka region (Vojvodina Autonomous Province, North Serbia for the purpose of droughts/water shortage monitoring and remote sensing under ongoing IPA project 'Water shortage hazard and adaptive water management strategies in the Hungarian-Serbian cross-border region' (WAHASTRAT. The main objective of this project is to determine water shortage con­flicts on a local and regional level, and to reveal the frequency, extent and severity of future hydro-cli­matic hazards. The locations of eight measurement stations selected on the principle of representativeness in term of terrain configuration and soil cover. An area in which measurement stations were placed, covers about 1000 km2 (12% of total area of Bačka and includes geomorphic units which reliable represent the relief of the whole Bačka region. Measurement stations were placed on 4 out of 5 most common soil types in the Bačka and Vojvodina: chernozem, alluvial soils, smonitza and saline and alkali soils. A measurement equipment system was constructed for the requirements of the WAHASTRAT project. The aim was to design a user-friendly and affordable IT solution, which would enable continuous re­mote monitoring of meteorological parameters and soil moisture. Independent solar-powered meas­urement stations are able to automatically measure air temperature, air humidity, wind speed, wind di­rection, precipitation and soil moisture.

  4. Measurement of natural and anthropogenic radiation in surface waters

    International Nuclear Information System (INIS)

    Turcotte, Jacques

    1981-01-01

    The use of alumina gel in municipal water treatment plants is proving very promising for the measurement of radioactivity in watercourses. The amazing fixation power of aluminum hydroxide and the large volume of water treated daily in one plant permits alumina gel to concentrate traces of natural and artificial radioisotopes to a level at which it becomes possible to observe very small amounts of radioactive fallout from nuclear tests, or even to follow over hundreds of kilometers the wastes of nuclear stations, no matter how weak the radioactivity may be [fr

  5. The Global Energy Balance Archive (GEBA): A database for the worldwide measured surface energy fluxes

    Science.gov (United States)

    Wild, Martin; Ohmura, Atsumu; Schär, Christoph; Müller, Guido; Hakuba, Maria Z.; Mystakidis, Stefanos; Arsenovic, Pavle; Sanchez-Lorenzo, Arturo

    2017-02-01

    The Global Energy Balance Archive (GEBA) is a database for the worldwide measured energy fluxes at the Earth's surface. GEBA is maintained at ETH Zurich (Switzerland) and has been founded in the 1980s by Prof. Atsumu Ohmura. It has continuously been updated and currently contains around 2500 stations with 500`000 monthly mean entries of various surface energy balance components. Many of the records extend over several decades. The most widely measured quantity available in GEBA is the solar radiation incident at the Earth's surface ("global radiation"). The data sources include, in addition to the World Radiation Data Centre (WRDC) in St. Petersburg, data reports from National Weather Services, data from different research networks (BSRN, ARM, SURFRAD), data published in peer-reviewed publications and data obtained through personal communications. Different quality checks are applied to check for gross errors in the dataset. GEBA is used in various research applications, such as for the quantification of the global energy balance and its spatiotemporal variation, or for the estimation of long-term trends in the surface fluxes, which enabled the detection of multi-decadal variations in surface solar radiation, known as "global dimming" and "brightening". GEBA is further extensively used for the evaluation of climate models and satellite-derived surface flux products. On a more applied level, GEBA provides the basis for engineering applications in the context of solar power generation, water management, agricultural production and tourism. GEBA is publicly accessible over the internet via www.geba.ethz.ch.

  6. 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

  7. A noncontact laser system for measuring soil surface topography

    International Nuclear Information System (INIS)

    Huang, C.; White, I.; Thwaite, E.G.; Bendeli, A.

    1988-01-01

    Soil surface topography profoundly influences runoff hydrodynamics, soil erosion, and surface retention of water. Here we describe an optical noncontact system for measuring soil surface topography. Soil elevation is measured by projecting a laser beam onto the surface and detecting the position of the interception point. The optical axis of the detection system is oriented at a small angle to the incident beam. A low-power HeNe (Helium-Neon) laser is used as the laser source, a photodiode array is used as the laser image detector and an ordinary 35-mm single lens reflex camera provides the optical system to focus the laser image onto the diode array. A wide spectrum of measurement ranges (R) and resolutions are selectable, from 1 mm to 1 m. These are determined by the laser-camera distance and angle, the focal length of the lens, and the sensing length of the diode array and the number of elements (N) contained in the array. The resolution of the system is approximately R/2N. We show for the system used here that this resolution is approximately 0.2%. In the configuration selected, elevation changes of 0.16 mm could be detected over a surface elevation range of 87 mm. The sampling rate of the system is 1000 Hz, which permits soil surfaces to be measured at speeds of up to 1 m s −1 with measurements taken at 1-mm spacing. Measurements of individual raindrop impacts on the soil and of soil surfaces before and after rain show the versatility of the laser surface profiler, which has applications in studies of erosion processes, surface storage and soil trafficability

  8. Surface energy balance and turbulence measurements on Warszawa Icefield, King George Island, West Antarctica

    Science.gov (United States)

    Falk, U.; Sala, H.; Braun, M.

    2012-12-01

    The Antarctic Peninsula is amongst the fastest warming places on Earth and further temperature increase is to be expected. It has undergone rapid environmental changes in the past decades. Exceptional rates of surface air temperature increases (2.5K in 50 years) are concurrent with retreating glacier fronts, an increase in melt areas, surface lowering and rapid retreat of glaciers, break-up and disintegration of ice shelves. The South Shetland Islands are located on the northern tip of the Antarctic Peninsula and are especially vulnerable to climate change due to their maritime climate. For King George Island we have compiled a unique data set comprising direct measurements of evaporation and sensible heat flux by eddy covariance on the Warszawa Icefield over 1.5 years from November 2010 to 2012 in combination with a fully equipped automated weather station measuring long- and short-wave radiation components, profiles of temperature, humidity and wind velocities as well as glacier ice temperatures. The combination with the eddy covariance data allows for analysis of variability and seasonality of surface energy balance components on a glacier for one and a half years. Repeat measurements of snow accumulation and surface lowering along transects on the glacier and at different locations on King George Island are used for analysis of multi-sensor satellite data to identify melt patterns and bare ice areas during summer within the source area of the ground measurements. In combination with long-term time series of weather data, these data give indication of the sensitivity of the ice cap to the ongoing changes. This research is part of the ESF project IMCOAST funded by BMBF. Field work was carried out at the Dallmann laboratory (Carlini station, King George Island/Isla 25 de Mayo) in cooperation of the Instituto Antartico Argentino (Argentina) and the Alfred-Wegener Institute of Marine and Polar Research (Germany).

  9. Dynamic Bubble Surface Tension Measurements in Northwest Atlantic Seawater

    Science.gov (United States)

    Kieber, D. J.; Long, M. S.; Keene, W. C.; Kinsey, J. D.; Frossard, A. A.; Beaupre, S. R.; Duplessis, P.; Maben, J. R.; Lu, X.; Chang, R.; Zhu, Y.; Bisgrove, J.

    2017-12-01

    Numerous reports suggest that most organic matter (OM) associated with newly formed primary marine aerosol (PMA) originates from the sea-surface microlayer. However, surface-active OM rapidly adsorbs onto bubble surfaces in the water column and is ejected into the atmosphere when bubbles burst at the air-water interface. Here we present dynamic surface tension measurements of bubbles produced in near surface seawater from biologically productive and oligotrophic sites and in deep seawater collected from 2500 m in the northwest Atlantic. In all cases, the surface tension of bubble surfaces decreased within seconds after the bubbles were exposed to seawater. These observations demonstrate that bubble surfaces are rapidly saturated by surfactant material scavenged from seawater. Spatial and diel variability in bubble surface evolution indicate corresponding variability in surfactant concentrations and/or composition. Our results reveal that surface-active OM is found throughout the water column, and that at least some surfactants are not of recent biological origin. Our results also support the hypothesis that the surface microlayer is a minor to negligible source of OM associated with freshly produced PMA.

  10. Investigation of gasoline distributions within petrol stations: spatial and seasonal concentrations, sources, mitigation measures, and occupationally exposed symptoms.

    Science.gov (United States)

    Sairat, Theerapong; Homwuttiwong, Sahalaph; Homwutthiwong, Kritsana; Ongwandee, Maneerat

    2015-09-01

    We measured levels of VOCs and determined the distributions of benzene concentrations over the area of two petrol stations in all three seasons. Using the concentrations and sampling positions, we created isoconcentration contour maps. The average concentrations ranged 18-1288 μg m(-3) for benzene and 12-81 μg m(-3) for toluene. The contour maps indicate that high-level contours of benzene were found not only at the fuel dispenser areas but also at the storage tank refilling points, open drainage areas where gasoline-polluted wastewater was flowing, and the auto service center located within the station area. An assessment of the benzene to toluene ratio contour plots implicates that airborne benzene and toluene near the fuel dispenser area were attributed to gasoline evaporation although one of the studied stations may be influenced by other VOC sources besides gasoline evaporation. Additionally, during the routine refilling of the underground fuel storage tanks by a tank truck, the ambient levels of benzene and toluene increased tremendously. The implementation of source control by replacing old dispensers with new fuel dispensers that have an efficient cutoff feature and increased delivery speed can reduce spatial benzene concentrations by 77%. Furthermore, a questionnaire survey among 63 service attendants in ten stations revealed that headache was the most reported health complaint with a response rate of 32%, followed by fatigue with 20%. These prominent symptoms could be related to an exposure to high benzene concentrations.

  11. 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.)

  12. Measurement for Surface Tension of Aqueous Inorganic Salt

    Directory of Open Access Journals (Sweden)

    Jiming Wen

    2018-03-01

    Full Text Available Bubble columns are effective means of filtration in filtered containment venting systems. Here, the surface tension has a significant influence on bubble size distribution and bubble deformation, which have a strong impact on the behavior of the bubble column. The influence of aqueous inorganic compounds on the surface tension depends on the electrolytic activity, Debye length, entropy of ion hydration, and surface deficiencies or excess. In this work, the surface tensions of same specific aqueous solutions have been measured by different methods including platinum plate method, platinum ring method, and maximum bubble pressure method. The measured surface tensions of both sodium hydroxide and sodium thiosulfate are less than that of water. As solution temperature ranges from 20 to 75°C, the surface tension of 0.5 mol/L sodium hydroxide solution decreases from 71 to 55 mN/m while that of 1 mol/L solution decreases from 60 to 45 mN/m. Similarly during the same temperature range, the surface tension of 0.5 mol/L sodium thiosulfate decreases from 70 to 38 mN/m, and that of 1 mol/L sodium thiosulfate is between 68 and 36 mN/m. The analysis for the influence mechanism of aqueous inorganic on surface tension is provided. In addition, experimental results show that the surface tension of solid aerosol suspension liquid has no obvious difference from that of distilled water.

  13. Measurements of greenhouse gases and related tracers at Bialystok tall tower station in Poland

    Directory of Open Access Journals (Sweden)

    M. E. Popa

    2010-03-01

    Full Text Available Quasi-continuous, in-situ measurements of atmospheric CO2, O2/N2, CH4, CO, N2O, and SF6 have been performed since August 2005 at the tall tower station near Bialystok, in Eastern Poland, from five heights up to 300 m. Besides the in-situ measurements, flask samples are filled approximately weekly and measured at Max-Planck Institute for Biogeochemistry for the same species and, in addition, for H2, Ar/N2 and the stable isotopes 13C and 18O in CO2. The in-situ measurement system was built based on commercially available analysers: a LiCor 7000 for CO2, a Sable Systems "Oxzilla" FC-2 for O2, and an Agilent 6890 gas chromatograph for CH4, CO, N2O and SF6. The system was optimized to run continuously with very little maintenance and to fulfill the precision requirements of the CHIOTTO project. The O2/N2 measurements in particular required special attention in terms of technical setup and quality assurance. The evaluation of the performance after more than three years of operation gave overall satisfactory results, proving that this setup is suitable for long term remote operation with little maintenance. The precision achieved for all species is within or close to the project requirements. The comparison between the in-situ and flask sample results, used to verify the accuracy of the in-situ measurements, showed no significant difference for CO2, O2/N2, CH4 and N2O, and a very small difference for SF6. The same comparison however revealed a statistically significant difference for CO, of about 6.5 ppb, for which the cause could not be fully explained.

    From more than three years of data, the main features at Bialystok have been characterized in terms of variability, trends, and

  14. RZP 202 - a modular system for surface density measurement

    International Nuclear Information System (INIS)

    Severa, L.; Merinsky, J.

    The sensing element is an ionization chamber of the type that has maximum sensitivity to beta radiation of the used radionuclide ( 147 Pm, 85 Kr, 90 Sr- 90 Y) or to gamma radiation of radionuclide 241 Am. Collimation shields were developed for the said sources. Measurement of the ionization currents is made with an electrometer with a vibration capacitor. Invariable configuration is secured by a measuring arm. The modular units are of the CAMAC system design. The surface density meters measure deviations from the rated surface density. The scale for inputting surface density is linear. The configuration, functional continuity of the individual parts and the possibility of variant designs of surface density meters are described and the technical parameters of RZP 202 and its configuration and design are given

  15. Development of the automatic measuring system to survey the surface contamination on equipments

    International Nuclear Information System (INIS)

    Ishizuka, Akira; Matsumura, Hidekatsu; Nawa, Takao; Yamaguchi, Seiji; Yamada, Tadashi.

    1980-01-01

    The inspection of surface contamination carried out when things are taken out of the control areas in nuclear power stations requires considerable labor and time because it is carried out manually. In order to make the inspection of surface contamination more efficiently and to standardize it, the development of an automatic inspection apparatus was carried out. This apparatus inspects the surface contamination due to radio isotopes which do not emit α-ray, and the objects to be measured are the large things with definite forms, such as boards and pipes for scaffolding. The method of measuring β-ray with a gas flow counter was adopted for the apparatus in view of the good detection sensitivity, relatively simple shielding against background, and easy conversion to surface contamination density. The measuring system was composed of the gas flow counters and a rate meter. The outline of the apparatus made for trial is explained. As the result of the performance test, the lowest detection sensitivity was 1.29 x 10 -5 μCi/cm 2 at the moving speed of an object of 1 cm/sec. The detection sensitivity is improved by the flattening of the sensitivity distribution. The evaluation of the error, the reduction of measuring time and the prevention of contamination were also made. (Kako, I.)

  16. Results of SPM sun photometer measurements at Mirny Antarctic station (58-60th RAE)

    Science.gov (United States)

    Kabanov, Dmitry M.; Prakhov, Aleksander N.; Radionov, Vladimir F.; Sakerin, Sergey M.

    2015-11-01

    The SPM portable sun photometer observations in the wavelength range of 0.34-2.14 μm are performed at Mirny Antarctic station since fall 2013. The data obtained are used to calculate the aerosol optical depth (AOD) and water vapor content of the atmosphere. The sun photometer intercalibration results and statistical characteristics of interdiurnal and seasonal variations in spectral AOD of the atmosphere are discussed. Estimates of interannual variations in the atmospheric AOD in the region of Mirny station and in the coastal zone of Antarctica are presented. The global background level of AOD of the Antarctic atmosphere is noted to be still about 0.02 at the wavelength of 0.5 μm.

  17. Inexpensive, Open-Source, Internet of Things-Enabled Sensing Stations for Environmental Parameter Measurements

    Science.gov (United States)

    Marchetto, P. M.; Hofmeister, K.; Walter, M. T.

    2015-12-01

    In the age of the Internet, data is inherently portable. Given the shrinking numbers of stream gauges in the US under the banner of the USGS and the lack of collocation of sensors for environmental parameters, it is clear the only way to collect these data is with near real-time, multi-parameters sensing stations. We are designing a system that can be built and deployed for under $300 by community groups interested in learning more about the land that they are protecting, such as conservation groups, or groups interested in the basic science behind sensing and ecology, such as makerspaces. Sensing stations like these will enable a greater diversity of data collection while increasing public awareness of environmental issues and the research process.

  18. Measurement and analysis of temperature, strain and stress of foundation mat concrete in nuclear and thermal power stations

    International Nuclear Information System (INIS)

    Haraguchi, Akira; Yamakawa, Hidetsugu; Abe, Hirotoshi

    1981-01-01

    The problems of the thermal stress in concrete structures are roughly divided into the initial stress due to setting heat and the stress due to external temperature after hardening. The initial stress exists in every concrete structure, and it is usually neglected in beams and columns, but it must be taken into account in case of the foundation mat structures in nuclear power stations, for example. In this paper, (1) the results of measurement of temperature, strain and stress in each lift at the time of and after placing concrete in the foundation mat of a nuclear power station and the comparison of them with the results of analysis, (2) the results of measurement of the temperature and stress in a foundation mat, which was carried out to rationalize the design method for the raft type foundation mats in thermal power stations, and (3) the results of examination on the analysis model, external force conditions and boundary conditions used for the design are reported. The analysis method for temperature and thermal stress by finite element method, developed by the Central Research Institute of Electric Power Industry, can take the changes in the heat of hydration in placed concrete, the creep phenomenon of concrete and the restraint at construction joints in consideration. It is necessary to collect the data on the measurement of mat concrete and to develop the accurate analysis method. (Kako, I.)

  19. Study on the Concentration Measurement of the Pollution Gases from Coal-Fired Power Station

    International Nuclear Information System (INIS)

    Zheng, L J; Li, W

    2006-01-01

    CO 2 is a main kind of pollution gases discharged from coal-fired power station. The relationship between gas concentration and pressure, temperature is deduced base on the law of Beer-Lambert and the theory of gas line-shape. The tunable diode laser spectral technology is used to analyze the changing regularity of the peak, half-peak width of the absorption curve with pressure and temperature

  20. Advances in the Surface Renewal Flux Measurement Method

    Science.gov (United States)

    Shapland, T. M.; McElrone, A.; Paw U, K. T.; Snyder, R. L.

    2011-12-01

    The measurement of ecosystem-scale energy and mass fluxes between the planetary surface and the atmosphere is crucial for understanding geophysical processes. Surface renewal is a flux measurement technique based on analyzing the turbulent coherent structures that interact with the surface. It is a less expensive technique because it does not require fast-response velocity measurements, but only a fast-response scalar measurement. It is therefore also a useful tool for the study of the global cycling of trace gases. Currently, surface renewal requires calibration against another flux measurement technique, such as eddy covariance, to account for the linear bias of its measurements. We present two advances in the surface renewal theory and methodology that bring the technique closer to becoming a fully independent flux measurement method. The first advance develops the theory of turbulent coherent structure transport associated with the different scales of coherent structures. A novel method was developed for identifying the scalar change rate within structures at different scales. Our results suggest that for canopies less than one meter in height, the second smallest coherent structure scale dominates the energy and mass flux process. Using the method for resolving the scalar exchange rate of the second smallest coherent structure scale, calibration is unnecessary for surface renewal measurements over short canopies. This study forms the foundation for analysis over more complex surfaces. The second advance is a sensor frequency response correction for measuring the sensible heat flux via surface renewal. Inexpensive fine-wire thermocouples are frequently used to record high frequency temperature data in the surface renewal technique. The sensible heat flux is used in conjunction with net radiation and ground heat flux measurements to determine the latent heat flux as the energy balance residual. The robust thermocouples commonly used in field experiments

  1. Subsurface soil and water pollution by diesel fuel at Bozdarevac railway station near Belgrade and remedial measures

    International Nuclear Information System (INIS)

    Vujasinovic, S.; Matic, D.I.

    1991-01-01

    An excessive pollution of ground water and the hydrogeologic environment by naphtha and its derivatives spilled on the surface has been recorded in Yugoslavia. The similar accidents in Serbia (Obrenovac, Uzicka Pozega, Beograd-Makis, Beograd-Danube railway station, Leskovac, Bozdarevac, etc.) have increased in number in the last several years. Transportation of naphtha and its derivatives, either by road or river, from the refineries to the consumers is obviously contributing much to the environmental pollution hazard. For the wide range of use and the specific effect on ground water, this pollutant can be taken for one of the first order. This paper discusses a case example. (Author)

  2. On the representation of regional characteristics by hydrographic measurements at central stations in four deep basins of the Baltic Sea

    Directory of Open Access Journals (Sweden)

    J. H. Reissmann

    2006-01-01

    Full Text Available In this work the eddy resolving data sets of salinity, temperature, and oxygen content aquired in the framework of the German-Russian project MESODYN (MESOscale DYNamics in the Arkona Basin, the Bornholm Basin, the Stolpe Furrow, and the Eastern Gotland Basin during summer and winter stratification situations are utilized to examine to which extent the observations at the central monitoring stations within these basins are representative for the spatial mean state of the corresponding region with respect to comparative monitoring purposes of the whole Baltic Sea. The investigation covers profiles of salinity, potential temperature, oxygen content, potential density, and squared buoyancy or Brunt-Väisälä frequency. Moreover, some parameters of the halocline, namely its depth, thickness, and upper and lower boundaries, and the first baroclinic Rossby radii are subject to the investigation. The profiles match best for the squared buoyancy or Brunt-Väisälä frequency. The profiles of salinity match best in the Eastern Gotland Basin and worst in the Arkona Basin both for summer and winter stratification situations. The overall agreement for the halocline parameters is good. The baroclinic Rossby radii match their spatial mean values well, if the depth range considered for their calculation is restricted to the mean depth in each region at the bottom side. In doing so they also match the spatial mean values of the first baroclinic Rossby radii calculated considering the whole depth range at each station. Overall, the regional characteristics of the investigated quantities and parameters are represented well by the hydrographic measurements at the central stations in the four regions in spite of some significant differences between the spatial mean states and the observations at the central stations. In particular, the observations at the central stations seem to be usefull for comparisons between these regions. However, the observed differences

  3. Outdoor surface temperature measurement: ground truth or lie?

    Science.gov (United States)

    Skauli, Torbjorn

    2004-08-01

    Contact surface temperature measurement in the field is essential in trials of thermal imaging systems and camouflage, as well as for scene modeling studies. The accuracy of such measurements is challenged by environmental factors such as sun and wind, which induce temperature gradients around a surface sensor and lead to incorrect temperature readings. In this work, a simple method is used to test temperature sensors under conditions representative of a surface whose temperature is determined by heat exchange with the environment. The tested sensors are different types of thermocouples and platinum thermistors typically used in field trials, as well as digital temperature sensors. The results illustrate that the actual measurement errors can be much larger than the specified accuracy of the sensors. The measurement error typically scales with the difference between surface temperature and ambient air temperature. Unless proper care is taken, systematic errors can easily reach 10% of this temperature difference, which is often unacceptable. Reasonably accurate readings are obtained using a miniature platinum thermistor. Thermocouples can perform well on bare metal surfaces if the connection to the surface is highly conductive. It is pointed out that digital temperature sensors have many advantages for field trials use.

  4. 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...

  5. Noise evaluation of a point autofocus surface topography measuring instrument

    Science.gov (United States)

    Maculotti, Giacomo; Feng, Xiaobing; Galetto, Maurizio; Leach, Richard

    2018-06-01

    In this work, the measurement noise of a point autofocus surface topography measuring instrument is evaluated, as the first step towards establishing a route to traceability for this type of instrument. The evaluation is based on the determination of the metrological characteristics for noise as outlined in draft ISO specification standards by using a calibrated optical flat. The static noise and repeatability of the autofocus sensor are evaluated. The influence of environmental disturbances on the measured surface topography and the built-in software to compensate for such influences are also investigated. The instrument was found to have a measurement noise of approximately 2 nm or, when expressed with the measurement bandwidth, 0.4 nm for a single-point measurement.

  6. 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.)

  7. 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

  8. Optimization of measurement methods for a multi-frequency electromagnetic field from mobile phone base station using broadband EMF meter

    Directory of Open Access Journals (Sweden)

    Paweł Bieńkowski

    2015-10-01

    Full Text Available Background: This paper presents the characteristics of the mobile phone base station (BS as an electromagnetic field (EMF source. The most common system configurations with their construction are described. The parameters of radiated EMF in the context of the access to methods and other parameters of the radio transmission are discussed. Attention was also paid to antennas that are used in this technology. Material and Methods: The influence of individual components of a multi-frequency EMF, most commonly found in the BS surroundings, on the resultant EMF strength value indicated by popular broadband EMF meters was analyzed. The examples of metrological characteristics of the most common EMF probes and 2 measurement scenarios of the multisystem base station, with and without microwave relays, are shown. Results: The presented method for measuring the multi-frequency EMF using 2 broadband probes allows for the significant minimization of measurement uncertainty. Equations and formulas that can be used to calculate the actual EMF intensity from multi-frequency sources are shown. They have been verified in the laboratory conditions on a specific standard setup as well as in real conditions in a survey of the existing base station with microwave relays. Conclusions: Presented measurement methodology of multi-frequency EMF from BS with microwave relays, validated both in laboratory and real conditions. It has been proven that the described measurement methodology is the optimal approach to the evaluation of EMF exposure in BS surrounding. Alternative approaches with much greater uncertainty (precaution method or more complex measuring procedure (sources exclusion method are also presented. Med Pr 2015;66(5:701–712

  9. [Optimization of measurement methods for a multi-frequency electromagnetic field from mobile phone base station using broadband EMF meter].

    Science.gov (United States)

    Bieńkowski, Paweł; Cała, Paweł; Zubrzak, Bartłomiej

    2015-01-01

    This paper presents the characteristics of the mobile phone base station (BS) as an electromagnetic field (EMF) source. The most common system configurations with their construction are described. The parameters of radiated EMF in the context of the access to methods and other parameters of the radio transmission are discussed. Attention was also paid to antennas that are used in this technology. The influence of individual components of a multi-frequency EMF, most commonly found in the BS surroundings, on the resultant EMF strength value indicated by popular broadband EMF meters was analyzed. The examples of metrological characteristics of the most common EMF probes and 2 measurement scenarios of the multisystem base station, with and without microwave relays, are shown. The presented method for measuring the multi-frequency EMF using 2 broadband probes allows for the significant minimization of measurement uncertainty. Equations and formulas that can be used to calculate the actual EMF intensity from multi-frequency sources are shown. They have been verified in the laboratory conditions on a specific standard setup as well as in real conditions in a survey of the existing base station with microwave relays. Presented measurement methodology of multi-frequency EMF from BS with microwave relays, validated both in laboratory and real conditions. It has been proven that the described measurement methodology is the optimal approach to the evaluation of EMF exposure in BS surrounding. Alternative approaches with much greater uncertainty (precaution method) or more complex measuring procedure (sources exclusion method) are also presented). This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  10. Surface Forces Apparatus measurements of interactions between rough and reactive calcite surfaces.

    Science.gov (United States)

    Dziadkowiec, Joanna; Javadi, Shaghayegh; Bratvold, Jon Einar; Nilsen, Ola; Røyne, Anja

    2018-05-28

    Nm-range forces acting between calcite surfaces in water affect macroscopic properties of carbonate rocks and calcite-based granular materials, and are significantly influenced by calcite surface recrystallization. We suggest that the repulsive mechanical effects related to nm-scale surface recrystallization of calcite in water could be partially responsible for the observed decrease of cohesion in calcitic rocks saturated with water. Using the Surface Forces Apparatus (SFA), we simultaneously followed the calcite reactivity and measured the forces in water in two surface configurations: between two rough calcite surfaces (CC), or between rough calcite and a smooth mica surface (CM). We used nm-scale rough, polycrystalline calcite films prepared by Atomic Layer Deposition (ALD). We measured only repulsive forces in CC in CaCO 3 -saturated water, which was related to roughness and possibly to repulsive hydration effects. Adhesive or repulsive forces were measured in CM in CaCO 3 -saturated water depending on calcite roughness, and the adhesion was likely enhanced by electrostatic effects. The pull-off adhesive force in CM became stronger with time and this increase was correlated with a decrease of roughness at contacts, which parameter could be estimated from the measured force-distance curves. That suggested a progressive increase of real contact areas between the surfaces, caused by gradual pressure-driven deformation of calcite surface asperities during repeated loading-unloading cycles. Reactivity of calcite was affected by mass transport across nm to µm-thick gaps between the surfaces. Major roughening was observed only for the smoothest calcite films, where gaps between two opposing surfaces were nm-thick over µm-sized areas, and led to force of crystallization that could overcome confining pressures of the order of MPa. Any substantial roughening of calcite caused a significant increase of the repulsive mechanical force contribution.

  11. The New Horizons Radio Science Experiment: Performance and Measurements of Pluto's Atmospheric Structure, Surface Pressure, and Surface Temperature

    Science.gov (United States)

    Linscott, I.; Hinson, D. P.; Bird, M. K.; Stern, A.; Weaver, H. A., Jr.; Olkin, C.; Young, L. A.; Ennico Smith, K.

    2015-12-01

    The New Horizons (NH) spacecraft payload contained the Radio Science Experiment (REX) for determining key characteristics of Pluto and Charon during the July 14, 2015, flyby of the Pluto/Charon system. The REX flight equipment augments the NH X-band radio transceiver by providing a high precision, narrow band recording of high power uplink transmissions from Earth stations, as well as a record of broadband radiometric power. This presentation will review the performance and initial results of two high- priority observations. First, REX received two pair of 20-kW signals, one pair per polarization, transmitted from the DSN at 4.2-cm wavelength during a diametric radio occultation by Pluto. REX recorded these uplink signals and determined precise measurement of the surface pressure, the temperature structure of the lower atmosphere, and the surface radius of Pluto. The ingress portion of one polarization was played back from the spacecraft in July and processed to obtain the pressure and temperature structure of Pluto's atmosphere. Second, REX measured the thermal emission from Pluto at 4.2- cm wavelength during two linear scans across the disk at close range when both the dayside and the night side are visible. Both scans extend from limb to limb with a resolution of one-tenth Pluto's disk and temperature resolution of 0.1 K. Occultation and radiometric temperature results presented here will encompass additional data scheduled for playback in September.

  12. UMTS Network Stations

    Science.gov (United States)

    Hernandez, C.

    2010-09-01

    The weakness of small island electrical grids implies a handicap for the electrical generation with renewable energy sources. With the intention of maximizing the installation of photovoltaic generators in the Canary Islands, arises the need to develop a solar forecasting system that allows knowing in advance the amount of PV generated electricity that will be going into the grid, from the installed PV power plants installed in the island. The forecasting tools need to get feedback from real weather data in "real time" from remote weather stations. Nevertheless, the transference of this data to the calculation computer servers is very complicated with the old point to point telecommunication systems that, neither allow the transfer of data from several remote weather stations simultaneously nor high frequency of sampling of weather parameters due to slowness of the connection. This one project has developed a telecommunications infrastructure that allows sensorizadas remote stations, to send data of its sensors, once every minute and simultaneously, to the calculation server running the solar forecasting numerical models. For it, the Canary Islands Institute of Technology has added a sophisticated communications network to its 30 weather stations measuring irradiation at strategic sites, areas with high penetration of photovoltaic generation or that have potential to host in the future photovoltaic power plants connected to the grid. In each one of the stations, irradiance and temperature measurement instruments have been installed, over inclined silicon cell, global radiation on horizontal surface and room temperature. Mobile telephone devices have been installed and programmed in each one of the weather stations, which allow the transfer of their data taking advantage of the UMTS service offered by the local telephone operator. Every minute the computer server running the numerical weather forecasting models receives data inputs from 120 instruments distributed

  13. Assimilation of MODIS Ice Surface Temperature and Albedo into the Snow and Ice Model CROCUS Over the Greenland Ice Sheet Along the K-transect Stations

    Science.gov (United States)

    Navari, M.; Margulis, S. A.; Bateni, S. M.; Alexander, P. M.; Tedesco, M.

    2016-12-01

    Estimating the Greenland Ice Sheet (GrIS) surface mass balance (SMB) is an important component of current and future projections of sea level rise. In situ measurement provides direct estimates of the SMB, but are inherently limited by their spatial extent and representativeness. Given this limitation, physically based regional climate models (RCMs) are critical for understanding GrIS physical processes and estimating of the GrIS SMB. However, the uncertainty in estimates of SMB from RCMs is still high. Surface remote sensing (RS) has been used as a complimentary tool to characterize various aspects related to the SMB. The difficulty of using these data streams is that the links between them and the SMB terms are most often indirect and implicit. Given the lack of in situ information, imperfect models, and under-utilized RS data it is critical to merge the available data in a systematic way to better characterize the spatial and temporal variation of the GrIS SMB. This work proposes a data assimilation (DA) framework that yields temporally-continuous and physically consistent SMB estimates that benefit from state-of-the-art models and relevant remote sensing data streams. Ice surface temperature (IST) is the most important factor that regulates partitioning of the net radiation into the subsurface snow/ice, sensible and latent heat fluxes and plays a key role in runoff generation. Therefore it can be expected that a better estimate of surface temperature from a data assimilation system would contribute to a better estimate of surface mass fluxes. Albedo plays an important role in the surface energy balance of the GrIS. However, even advanced albedo modules are not adequate to simulate albedo over the GrIS. Therefore, merging remotely sensed albedo product into a physically based model has a potential to improve the estimates of the GrIS SMB. In this work a MODIS-derived IST and a 16-day albedo product are independently assimilated into the snow and ice model CROCUS

  14. Quasi-periodic oscillations of aerosol backscatter profiles and surface meteorological parameters during winter nights over a tropical station

    Directory of Open Access Journals (Sweden)

    M. G. Manoj

    2011-03-01

    Full Text Available Atmospheric gravity waves, which are a manifestation of the fluctuations in buoyancy of the air parcels, are well known for their direct influence on concentration of atmospheric trace gases and aerosols, and also on oscillations of meteorological variables such as temperature, wind speed, visibility and so on. The present paper reports quasi-periodic oscillations in the lidar backscatter signal strength due to aerosol fluctuations in the nocturnal boundary layer, studied with a high space-time resolution polarimetric micro pulse lidar and concurrent meteorological parameters over a tropical station in India. The results of the spectral analysis of the data, archived on some typical clear-sky conditions during winter months of 2008 and 2009, exhibit a prominent periodicity of 20–40 min in lidar-observed aerosol variability and show close association with those observed in the near-surface temperature and wind at 5% statistical significance. Moreover, the lidar aerosol backscatter signal strength variations at different altitudes, which have been generated from the height-time series of the one-minute interval profiles at 2.4 m vertical resolution, indicate vertical propagation of these waves, exchanging energy between lower and higher height levels. Such oscillations are favoured by the stable atmospheric background condition and peculiar topography of the experimental site. Accurate representation of these buoyancy waves is essential in predicting the sporadic fluctuations of weather in the tropics.

  15. A Model for the Sounding Rocket Measurement on an Ionospheric E-F Valley at the Hainan Low Latitude Station

    International Nuclear Information System (INIS)

    Wang Zheng; Shi Jiankui; Guan Yibing; Liu Chao; Zhu Guangwu; Torkar Klaus; Fredrich Martin

    2014-01-01

    To understand the physics of an ionospheric E-F valley, a new overlapping three-Chapman-layer model is developed to interpret the sounding rocket measurement in the morning (sunrise) on May 7, 2011 at the Hainan low latitude ionospheric observation station (19.5°N, 109.1°E). From our model, the valley width, depth and height are 43.0 km, 62.9% and 121.0 km, respectively. From the sounding rocket observation, the valley width, depth and height are 42.2 km, 47.0% and 123.5 km, respectively. The model results are well consistent with the sounding rocket observation. The observed E-F valley at Hainan station is very wide and deep, and rapid development of the photochemical process in the ionosphere should be the underlying reason. (astrophysics and space plasma)

  16. 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.

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

    DEFF Research Database (Denmark)

    Corell, Dennis Dan; Sørensen, K.

    2017-01-01

    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......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...

  18. 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)

  19. Field measurement of albedo for limited extent test surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Sailor, David J. [Portland State University, Department of Mechanical and Materials Engineering, P.O. Box 751-ME, Portland, OR 97207 (United States); Resh, Kyle; Segura, Del [Tulane University, Department of Mechanical Engineering, 400 Lindy Boggs Center, New Orleans, LA 70118 (United States)

    2006-05-15

    A new method is introduced for field measurement of surface albedo. This method consists of the use of a cylindrical shade ring made of opaque fabric with a known (low) albedo placed over a test surface. The albedo measurement is accomplished using two small pyranometers situated so that the downward-facing pyranometer receives radiation only from the test surface and the shade ring. The upward-facing pyranometer simultaneously records the incoming solar radiation. The radiation received by the downward-facing pyramometer is a combination of reflected radiation from shaded and unshaded portions of these two surfaces, requiring detailed accounting of the resulting view factor geometries. The method presented here improves upon past approaches by allowing for smaller sample sizes, minimizing errors associated with reflective properties of the surroundings, and allowing for accurate measurements even under partially cloudy skies. In addition to these methodological improvements we introduce an approach for estimating the uncertainty in the resulting albedo measurements. Results from field measurements are presented to validate the measurement protocol, and to compare its accuracy with the accuracy of a published standard. (author)

  20. 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)

  1. 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.

  2. 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

  3. Optimized Estimation of Surface Layer Characteristics from Profiling Measurements

    Directory of Open Access Journals (Sweden)

    Doreene Kang

    2016-01-01

    Full Text Available New sampling techniques such as tethered-balloon-based measurements or small unmanned aerial vehicles are capable of providing multiple profiles of the Marine Atmospheric Surface Layer (MASL in a short time period. It is desirable to obtain surface fluxes from these measurements, especially when direct flux measurements are difficult to obtain. The profiling data is different from the traditional mean profiles obtained at two or more fixed levels in the surface layer from which surface fluxes of momentum, sensible heat, and latent heat are derived based on Monin-Obukhov Similarity Theory (MOST. This research develops an improved method to derive surface fluxes and the corresponding MASL mean profiles of wind, temperature, and humidity with a least-squares optimization method using the profiling measurements. This approach allows the use of all available independent data. We use a weighted cost function based on the framework of MOST with the cost being optimized using a quasi-Newton method. This approach was applied to seven sets of data collected from the Monterey Bay. The derived fluxes and mean profiles show reasonable results. An empirical bias analysis is conducted using 1000 synthetic datasets to evaluate the robustness of the method.

  4. Gallium surface diffusion on GaAs (001) surfaces measured by crystallization dynamics of Ga droplets

    International Nuclear Information System (INIS)

    Bietti, Sergio; Somaschini, Claudio; Esposito, Luca; Sanguinetti, Stefano; Fedorov, Alexey

    2014-01-01

    We present accurate measurements of Ga cation surface diffusion on GaAs surfaces. The measurement method relies on atomic force microscopy measurement of the morphology of nano–disks that evolve, under group V supply, from nanoscale group III droplets, earlier deposited on the substrate surface. The dependence of the radius of such nano-droplets on crystallization conditions gives direct access to Ga diffusion length. We found an activation energy for Ga on GaAs(001) diffusion E A =1.31±0.15 eV, a diffusivity prefactor of D 0  = 0.53(×2.1±1) cm 2 s −1 that we compare with the values present in literature. The obtained results permit to better understand the fundamental physics governing the motion of group III ad–atoms on III–V crystal surfaces and the fabrication of designable nanostructures.

  5. 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

  6. Measurement of surface recombination velocity on heavily doped indium phosphide

    International Nuclear Information System (INIS)

    Jenkins, P.; Ghalla-Goradia, M.; Faur, M.; Bailey, S.

    1990-01-01

    The controversy surrounding the published low values of surface recombination velocity (SRV) in n-InP, solidified in recent years when modeling of existing n/p InP solar cells revealed that the front surface SRV had to be higher than 1 x 10 6 cm/sec in order to justify the poor blue response that is characteristic of all n/p InP solar cells. In this paper, SRV on heavily doped (>10 18 cm -3 )n-type and p-type InP is measured as a function of surface treatment. For the limited range of substrates and surface treatments studied, SRV and surface stability depend strongly on the surface treatment. SRVs of ∼10 5 cm/sec in both p-type and n-type InP are obtainable, but in n-type the low SRV surfaces were unstable, and the only stable surfaces on n-type had SRVs of >10 6 cm/sec

  7. Reliability measurement for mixed mode failures of 33/11 kilovolt electric power distribution stations.

    Directory of Open Access Journals (Sweden)

    Faris M Alwan

    Full Text Available The reliability of the electrical distribution system is a contemporary research field due to diverse applications of electricity in everyday life and diverse industries. However a few research papers exist in literature. This paper proposes a methodology for assessing the reliability of 33/11 Kilovolt high-power stations based on average time between failures. The objective of this paper is to find the optimal fit for the failure data via time between failures. We determine the parameter estimation for all components of the station. We also estimate the reliability value of each component and the reliability value of the system as a whole. The best fitting distribution for the time between failures is a three parameter Dagum distribution with a scale parameter [Formula: see text] and shape parameters [Formula: see text] and [Formula: see text]. Our analysis reveals that the reliability value decreased by 38.2% in each 30 days. We believe that the current paper is the first to address this issue and its analysis. Thus, the results obtained in this research reflect its originality. We also suggest the practicality of using these results for power systems for both the maintenance of power systems models and preventive maintenance models.

  8. Measurement and on line control of radioactive contamination of the air using ASS-500 stations

    International Nuclear Information System (INIS)

    Jagielak, J.; Zak, A.; Biernacka, M.; Isajenko, K.; Lipinski, P.

    1998-01-01

    The method of continuous monitoring of artificial radionuclides in the ground-level atmosphere, used for early warning system in care of nuclear emergencies, is presented. The system consist of the scintillation spectrometer AS-01 mounted in the ASS-500 station cabinet. The results of calibrations and operational tests are given. For continuous operation mode the lower activity concentration limit is 0.44 Bq/m 3 for 131 I and 0.79 Bq/m 3 for 137 Cs. The activity concentration in the air of 10 Bq/m 3 for artificial radionuclides is used as the alarm threshold value. The ASS-500 station equipped with AS-01 spectrometer allows obtaining of the immediate information on the presence of artificial radionuclides in the air. The sampling process is not disturbed by AS-01 spectrometer. Therefore, the determination of the activity concentration in the air on the level of few μBq/m 3 by means of HPGe spectrometers is possible (author)

  9. Fermi surface measurements in actinide metals and compounds

    International Nuclear Information System (INIS)

    Arko, A.J.; Schirber, J.E.

    1978-01-01

    The various techniques of measuring Fermi Surface parameters are briefly discussed in terms f application to actinide systems. Particular emphasis is given the dHvA effect. Some general results found in the dHvA studies of actinide compounds are given. The dHvA effect has been measured in α-U and is presented in detail. None of the observed frequencies corresponds to closed surfaces. Results are compared to the calculations of Freeman, Koelling and Watson-Yang where qualitative agreement is observed

  10. 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.

  11. Lighting measurement station: measurements of natural lighting for characterization of sky and zenith illuminance; Estacao de medicao de iluminacao: medicao de niveis de iluminacao natural para caracterizacao de iluminancias de ceu e luminancia de zenite

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Roberta Vieira Goncalves de [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Escola de Arquitetura. Dept. de Tecnologia da Arquitetura e do Urbanismo]. E-mail: roberta@arq.ufmg.br; Pereira, Fernando Oscar Ruttkay [Santa Catarina Univ., Florianopolis, SC (Brazil). Dept. de Arquitetura. Lab. de Conforto Ambiental]. E-mail: feco@arq.ufsc.br

    2002-07-01

    This paper describes the assembly of a standard station for measuring the day lighting for evaluation of the natural light availability. The mounting and data obtention form will also be described from a standard IDMP day lighting station for measuring the data from measuring zenith, horizontal, and vertical illuminance of the sky and vertical irradiance for the cardinal points.

  12. Streamflow Gaging Stations

    Data.gov (United States)

    Department of Homeland Security — This map layer shows selected streamflow gaging stations of the United States, Puerto Rico, and the U.S. Virgin Islands, in 2013. Gaging stations, or gages, measure...

  13. MONITORING AND CONTROLLING ON SURFACE SETTLEMENT IN SAND AND GRAVEL STRATA CAUSED BY SUBWAY STATION CONSTRUCTION APPLYING PIPE-ROOF PRE-CONSTRUCTION METHOD (PPM

    Directory of Open Access Journals (Sweden)

    Xian Yang

    2017-07-01

    Full Text Available Pipe-roof Pre-construction Method (PPM is regarded as a safer method to construct underground space, especially suitable for the construction sites with dense surface buildings, underground pipelines and complicated geological conditions. Xinleyizhi Station of Shenyang Metro constructed by PPM. In order to ensure safety in construction, the whole construction process was closely monitored. In this paper, monitoring results of surface settlement in PPM is analyzed. According to the monitoring results, the most serious settlement occurred in pipes jacking, which was the first and the most crucial step in PPM. The settlement reasons in each step are discussed, and controlling methods of surface settlement in each step are elaborated. Through close monitoring and timely control, the construction of Xinleyizhi Station completed smoothly. Because of the obvious advantages of PPM, the method will be used more widely in construction of shallow buried excavation under complicated surrounding and geological conditions.

  14. 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.

  15. 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%

  16. Measuring the Surface Temperature of the Cryosphere using Remote Sensing

    Science.gov (United States)

    Hall, Dorothy K.

    2012-01-01

    A general description of the remote sensing of cryosphere surface temperatures from satellites will be provided. This will give historical information on surface-temperature measurements from space. There will also be a detailed description of measuring the surface temperature of the Greenland Ice Sheet using Moderate-Resolution Imaging Spectroradiometer (MODIS) data which will be the focus of the presentation. Enhanced melting of the Greenland Ice Sheet has been documented in recent literature along with surface-temperature increases measured using infrared satellite data since 1981. Using a recently-developed climate data record, trends in the clear-sky ice-surface temperature (IST) of the Greenland Ice Sheet have been studied using the MODIS IST product. Daily and monthly MODIS ISTs of the Greenland Ice Sheet beginning on 1 March 2000 and continuing through 31 December 2010 are now freely available to download at 6.25-km spatial resolution on a polar stereographic grid. Maps showing the maximum extent of melt for the entire ice sheet and for the six major drainage basins have been developed from the MODIS IST dataset. Twelve-year trends of the duration of the melt season on the ice sheet vary in different drainage basins with some basins melting progressively earlier over the course of the study period. Some (but not all) of the basins also show a progressively-longer duration of melt. The consistency of this IST record, with temperature and melt records from other sources will be discussed.

  17. Long-term trends of surface ozone and its influencing factors at the Mt Waliguan GAW station, China - Part 1: Overall trends and characteristics

    Science.gov (United States)

    Xu, Wanyun; Lin, Weili; Xu, Xiaobin; Tang, Jie; Huang, Jianqing; Wu, Hao; Zhang, Xiaochun

    2016-05-01

    Tropospheric ozone is an important atmospheric oxidant, greenhouse gas and atmospheric pollutant at the same time. The oxidation capacity of the atmosphere, climate, human and vegetation health can be impacted by the increase of the ozone level. Therefore, long-term determination of trends of baseline ozone is highly needed information for environmental and climate change assessment. So far, studies on the long-term trends of ozone at representative sites are mainly available for European and North American sites. Similar studies are lacking for China and many other developing countries. Measurements of surface ozone were carried out at a baseline Global Atmospheric Watch (GAW) station in the north-eastern Tibetan Plateau region (Mt Waliguan, 36°17' N, 100°54' E, 3816 m a.s.l.) for the period of 1994 to 2013. To uncover the variation characteristics, long-term trends and influencing factors of surface ozone at this remote site in western China, a two-part study has been carried out, with this part focusing on the overall characteristics of diurnal, seasonal and long-term variations and the trends of surface ozone. To obtain reliable ozone trends, we performed the Mann-Kendall trend test and the Hilbert-Huang transform (HHT) analysis on the ozone data. Our results confirm that the mountain-valley breeze plays an important role in the diurnal cycle of surface ozone at Waliguan, resulting in higher ozone values during the night and lower ones during the day, as was previously reported. Systematic diurnal and seasonal variations were found in mountain-valley breezes at the site, which were used in defining season-dependent daytime and nighttime periods for trend calculations. Significant positive trends in surface ozone were detected for both daytime (0.24 ± 0.16 ppbv year-1) and nighttime (0.28 ± 0.17 ppbv year-1). The largest nighttime increasing rate occurred in autumn (0.29 ± 0.11 ppbv year-1), followed by spring (0.24 ± 0.12 ppbv year-1), summer (0.22 ± 0

  18. Long-term trends of surface ozone and its influencing factors at the Mt. Waliguan GAW station, China - Part 1: Overall trends and characteristics

    Science.gov (United States)

    Xu, W. Y.; Lin, W. L.; Xu, X. B.; Tang, J.; Huang, J. Q.; Wu, H.; Zhang, X. C.

    2015-11-01

    Tropospheric ozone is an important atmospheric oxidant, greenhouse gas and atmospheric pollutant at the same time. The level of tropospheric ozone, particularly in the surface layer, is impacted by emissions of precursors and is subjected to meteorological conditions. Due its importance, the long-term variation trend of baseline ozone is highly needed for environmental and climate change assessment. So far, studies about the long-term trends of ozone at representative sites are mainly available for European and North American sites. Similar studies are lacking for China, a country with rapid economic growth for recent decades, and many other developing countries. To uncover the long-term characteristics and trends of baseline surface ozone, concentration in western China, measurements at a global baseline Global Atmospheric Watch (GAW) station in the north-eastern Tibetan Plateau region (Mt. Waliguan) for the period of 1994 to 2013 were analysed in this study, using a modified Mann-Kendall test and the Hilbert-Huang Transform analysis for the trend and periodicity analysis, respectively. Results reveal higher surface ozone during the night and lower during the day at Waliguan, due to mountain-valley breezes. A seasonal maximum in summer was found, which was probably caused by enhanced stratosphere-to-troposphere exchange events and/or by tropospheric photochemistry. Analysis suggests that there is a season-diurnal cycle in the three-dimensional winds on top of Mt. Waliguan. Season-dependent daytime and nighttime ranges of 6 h were determined based on the season-diurnal cycle in the three-dimensional winds and were used to sort subsets of ozone data for trend analysis. Significant increasing trends in surface ozone were detected for both daytime (1.5-2.7 ppbv 10 a-1) and nighttime (1.3-2.9 ppbv 10 a-1). Autumn and spring revealed the largest increase rates, while summer and winter showed relatively weaker increases. The HHT spectral analysis confirmed the increasing

  19. 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

  20. Diffuse Reflectance Spectroscopy for Surface Measurement of Liver Pathology.

    Science.gov (United States)

    Nilsson, Jan H; Reistad, Nina; Brange, Hannes; Öberg, Carl-Fredrik; Sturesson, Christian

    2017-01-01

    Liver parenchymal injuries such as steatosis, steatohepatitis, fibrosis, and sinusoidal obstruction syndrome can lead to increased morbidity and liver failure after liver resection. Diffuse reflectance spectroscopy (DRS) is an optical measuring method that is fast, convenient, and established. DRS has previously been used on the liver with an invasive technique consisting of a needle that is inserted into the parenchyma. We developed a DRS system with a hand-held probe that is applied to the liver surface. In this study, we investigated the impact of the liver capsule on DRS measurements and whether liver surface measurements are representative of the whole liver. We also wanted to confirm that we could discriminate between tumor and liver parenchyma by DRS. The instrumentation setup consisted of a light source, a fiber-optic contact probe, and two spectrometers connected to a computer. Patients scheduled for liver resection due to hepatic malignancy were included, and DRS measurements were performed on the excised liver part with and without the liver capsule and alongside a newly cut surface. To estimate the scattering parameters and tissue chromophore volume fractions, including blood, bile, and fat, the measured diffuse reflectance spectra were applied to an analytical model. In total, 960 DRS spectra from the excised liver tissue of 18 patients were analyzed. All factors analyzed regarding tumor versus liver tissue were significantly different. When measuring through the capsule, the blood volume fraction was found to be 8.4 ± 3.5%, the lipid volume fraction was 9.9 ± 4.7%, and the bile volume fraction was 8.2 ± 4.6%. No differences could be found between surface measurements and cross-sectional measurements. In measurements with/without the liver capsule, the differences in volume fraction were 1.63% (0.75-2.77), -0.54% (-2.97 to 0.32), and -0.15% (-1.06 to 1.24) for blood, lipid, and bile, respectively. This study shows that it is possible to manage DRS

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

    DEFF Research Database (Denmark)

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

    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, there is a n......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......, 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....

  2. 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.

  3. 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

  4. Thickness Measurement of Surface Attachment on Plate with Lamb Wave

    Science.gov (United States)

    Ma, Xianglong; Zhang, Yinghong; Wen, Lichao; He, Yehu

    2017-12-01

    Aiming at the thickness detection of the plate surface attachment, a nondestructive testing method based on the Lamb wave is presented. This method utilizes Lamb wave propagation characteristics of signals in a bi-layer medium to measure the surface attachment plate thickness. Propagation of Lamb wave in bi-layer elastic is modeled and analyzed. The two-dimensional simulation model of electromagnetic ultrasonic plate - scale is established. The simulation is conducted by software COMSOL for simulation analysis under different boiler scale thickness wave form curve. Through this study, the thickness of the attached material can be judged by analyzing the characteristics of the received signal when the thickness of the surface of the plate is measured.

  5. Surface moisture measurement system acceptance testing work plan

    International Nuclear Information System (INIS)

    Ritter, G.A.

    1996-01-01

    This work plan addresses testing of the Surface Moisture Measurement System (SMMS) at the Fuels and Materials Examination Facility (FMEF). The purpose of this plan is to define the scope of work, identify organizational responsibilities, describe test control requirements, and provide estimated costs and schedule associated with acceptance testing

  6. 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.

  7. 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...

  8. Observations of the Earth's magnetic field from the Space Station: Measurement at high and extremely low altitude using Space Station-controlled free-flyers

    Science.gov (United States)

    Webster, W., Jr.; Frawley, J. J.; Stefanik, M.

    1984-01-01

    Simulation studies established that the main (core), crustal and electrojet components of the Earth's magnetic field can be observed with greater resolution or over a longer time-base than is presently possible by using the capabilities provided by the space station. Two systems are studied. The first, a large lifetime, magnetic monitor would observe the main field and its time variation. The second, a remotely-piloted, magnetic probe would observe the crustal field at low altitude and the electrojet field in situ. The system design and the scientific performance of these systems is assessed. The advantages of the space station are reviewed.

  9. 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.

  10. Summary of Great East Japan Earthquake response at Onagawa Nuclear Power Station and further safety improvement measures

    International Nuclear Information System (INIS)

    Sato, Toru

    2013-01-01

    A large earthquake occurred on March 11, 2011 and tsunami was generated following it. The East Japan suffered serious damage by the earthquake and tsunami. This is called the Great East Japan Earthquake. Onagawa Nuclear Power Station (NPS) is located closest to the epicenter of Great East Japan Earthquake. We experienced intense shake by the earthquake and some flooding from the tsunami, however, we have succeeded safely cold shutdown of the reactors. In this paper, we introduce summary of Great East Japan Earthquake response a Onagawa NPS and safety improvement measures which are based on both experience of Onagawa NPS and lesson from Fukushima Daiichi NPS accident. (author)

  11. Dose measurements and LET-determination in space station MIR during the Russian long term flight RLF

    International Nuclear Information System (INIS)

    Vana, N.; Schoener, N.; Fugger, M.; Akatov, Y.; Shurshakov, V.

    1996-01-01

    For determination of the absorbed dose and the dose equivalent in complex mixed radiation fields, new methods were developed in the frame of the Austrian-Soviet space mission AUSTROMIR in October 1991. The method utilizes the changes of peak height ratios in thermoluminescence glowcurves. Peak height ratios depend on the linear energy transfer (LET) of absorbed radiation. This effect was calibrated in different radiation fields (alpha-, beta-, gamma-, neutron fields and heavy charged particle beams). The method was approached for dose measurements during several space programs (DOSIMIR, BION-10, PHOTONS). During the Russian long term flight RLF six dosemeter packets were exposed in three different periods. Two positions with different shielding (the working area and the cabin of the board engineer) were chosen for the exposition of the dosemeters during each period in order to measure the variation of absorbed dose as well as the variation of average LET of absorbed radiation within the habitable part of space station MIR. These results will be compared with the results during two former periods of measurements on space station MIR (AUSTROMIR/DOSIMIR) and results obtained inside of biosatellite BION-10 and during the space shuttle mission STS-60. (author)

  12. Measurements of greenhouse gases at Beromünster tall-tower station in Switzerland

    Directory of Open Access Journals (Sweden)

    T. A. Berhanu

    2016-06-01

    0.29 ppb for CO, CO2, and CH4, respectively, over 19 months of measurements. The values obtained for CO2 and CH4 are compliant with the WMO recommendations, while the value calculated for CO is higher than the recommendation. Since the installation of an air-conditioning system recently at the measurement cabin, we have acquired better temperature stability of the measurement system, but no significant improvement was observed in the measurement precision inferred from the target gas measurements. Therefore, it seems that the observed higher variation in CO measurements is associated with the instrumental noise, compatible with the precision provided by the manufacturer.

  13. 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.

  14. Wireless Sensor Node for Surface Seawater Density Measurements

    Directory of Open Access Journals (Sweden)

    Roberto Saletti

    2012-03-01

    Full Text Available An electronic meter to measure surface seawater density is presented. It is based on the measurement of the difference in displacements of a surface level probe and a weighted float, which according to Archimedes’ law depends on the density of the water. The displacements are simultaneously measured using a high-accuracy magnetostrictive sensor, to which a custom electronic board provides a wireless connection and power supply so that it can become part of a wireless sensor network. The electronics are designed so that different kinds of wireless networks can be used, by simply changing the wireless module and the relevant firmware of the microcontroller. Lastly, laboratory and at-sea tests are presented and discussed in order to highlight the functionality and the performance of a prototype of the wireless density meter node in a Bluetooth radio network. The experimental results show a good agreement of the values of the calculated density compared to reference hydrometer readings.

  15. Wireless sensor node for surface seawater density measurements.

    Science.gov (United States)

    Baronti, Federico; Fantechi, Gabriele; Roncella, Roberto; Saletti, Roberto

    2012-01-01

    An electronic meter to measure surface seawater density is presented. It is based on the measurement of the difference in displacements of a surface level probe and a weighted float, which according to Archimedes' law depends on the density of the water. The displacements are simultaneously measured using a high-accuracy magnetostrictive sensor, to which a custom electronic board provides a wireless connection and power supply so that it can become part of a wireless sensor network. The electronics are designed so that different kinds of wireless networks can be used, by simply changing the wireless module and the relevant firmware of the microcontroller. Lastly, laboratory and at-sea tests are presented and discussed in order to highlight the functionality and the performance of a prototype of the wireless density meter node in a Bluetooth radio network. The experimental results show a good agreement of the values of the calculated density compared to reference hydrometer readings.

  16. Field Measurement of Surface Ship Magnetic Signature Using Multiple AUVs

    Science.gov (United States)

    2009-10-01

    been equipped with a tri-axial fluxgate magnetometer and used to perform preliminary magnetic field measurements. Measurements of this type will be...mounted on the AUVs, shown in Fig. 1, was a three-axis fluxgate type [16] magnetometer with a range of ±100,000 nT and a sensitivity of 100μV/nT. The...surface ship. The system will employ a formation of multiple AUVs, each equipped with a magnetometer . The objective is to measure total magnetic

  17. Measurement of annual dose on porcelain using surface TLD method

    International Nuclear Information System (INIS)

    Xia Junding; Wang Weida; Leung, P.L.

    2001-01-01

    In order to improve accuracy of TL authentication test for porcelain, a method of measurement of annual dose using ultrathin (CaSO 4 :Tm) dosage layer on porcelain was studied. The TLD was placed on the part of porcelain without glaze. A comparison of measurement of annual dose for surface TLD, inside TLD and alpha counting on porcelain was made. The results show that this technique is suitable for measuring annual dose and improving accuracy of TL authentication test for both porcelain and pottery

  18. The role of a certified calibration laboratory in a station's measuring and test equipment calibration, repair, and documentation program

    International Nuclear Information System (INIS)

    Ebenstreit, K.; MacIntosh, N.

    1995-01-01

    This paper outlines the role of a Certified Calibration Laboratory in- ensuring that the requirements of Measuring and Test Equipment calibration, identification, and traceability are met and documented. The Nuclear environment is one which is subject to influences from numerous 'quality agents'. One of the fields which comes under the scrutiny of the quality agents is that of equipment calibration and repair (both field components and M and TE). There is a responsibility to produce a superior product for the Ontario Consumer. The maintenance and calibration of Station Systems and their components have a direct impact on this output. The Measuring and Test Equipment element in each of these needs can be addressed by having a defined group of Maintenance Staff to execute a Measuring and Test Equipment Program which meets specific parameters. (author)

  19. In vivo measurement of vocal fold surface resistance.

    Science.gov (United States)

    Mizuta, Masanobu; Kurita, Takashi; Dillon, Neal P; Kimball, Emily E; Garrett, C Gaelyn; Sivasankar, M Preeti; Webster, Robert J; Rousseau, Bernard

    2017-10-01

    A custom-designed probe was developed to measure vocal fold surface resistance in vivo. The purpose of this study was to demonstrate proof of concept of using vocal fold surface resistance as a proxy of functional tissue integrity after acute phonotrauma using an animal model. Prospective animal study. New Zealand White breeder rabbits received 120 minutes of airflow without vocal fold approximation (control) or 120 minutes of raised intensity phonation (experimental). The probe was inserted via laryngoscope and placed on the left vocal fold under endoscopic visualization. Vocal fold surface resistance of the middle one-third of the vocal fold was measured after 0 (baseline), 60, and 120 minutes of phonation. After the phonation procedure, the larynx was harvested and prepared for transmission electron microscopy. In the control group, vocal fold surface resistance values remained stable across time points. In the experimental group, surface resistance (X% ± Y% relative to baseline) was significantly decreased after 120 minutes of raised intensity phonation. This was associated with structural changes using transmission electron microscopy, which revealed damage to the vocal fold epithelium after phonotrauma, including disruption of the epithelium and basement membrane, dilated paracellular spaces, and alterations to epithelial microprojections. In contrast, control vocal fold specimens showed well-preserved stratified squamous epithelia. These data demonstrate the feasibility of measuring vocal fold surface resistance in vivo as a means of evaluating functional vocal fold epithelial barrier integrity. Device prototypes are in development for additional testing, validation, and for clinical applications in laryngology. NA Laryngoscope, 127:E364-E370, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  20. DNA conformation on surfaces measured by fluorescence self-interference.

    Science.gov (United States)

    Moiseev, Lev; Unlü, M Selim; Swan, Anna K; Goldberg, Bennett B; Cantor, Charles R

    2006-02-21

    The conformation of DNA molecules tethered to the surface of a microarray may significantly affect the efficiency of hybridization. Although a number of methods have been applied to determine the structure of the DNA layer, they are not very sensitive to variations in the shape of DNA molecules. Here we describe the application of an interferometric technique called spectral self-interference fluorescence microscopy to the precise measurement of the average location of a fluorescent label in a DNA layer relative to the surface and thus determine specific information on the conformation of the surface-bound DNA molecules. Using spectral self-interference fluorescence microscopy, we have estimated the shape of coiled single-stranded DNA, the average tilt of double-stranded DNA of different lengths, and the amount of hybridization. The data provide important proofs of concept for the capabilities of novel optical surface analytical methods of the molecular disposition of DNA on surfaces. The determination of DNA conformations on surfaces and hybridization behavior provide information required to move DNA interfacial applications forward and thus impact emerging clinical and biotechnological fields.

  1. 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

  2. Measurements of the near-surface flow over a hill

    Science.gov (United States)

    Vosper, S. B.; Mobbs, S. D.; Gardiner, B. A.

    2002-10-01

    The near-surface flow over a hill with moderate slope and height comparable with the boundary-layer depth is investigated through field measurements of the mean flow (at 2 m), surface pressure, and turbulent momentum flux divergence between 8 and 15 m. The measurements were made along an east-west transect across the hill Tighvein (height 458 m, approximate width 8 km) on the Isle of Arran, south-west Scotland, during two separate periods, each of around three-weeks duration. Radiosonde ascents are used to determine the variation of a Froude number, FL = U/NL, where U is the wind speed at the middle-layer height, hm, N is the mean Brunt-Väisälä frequency below this height and L is a hill length-scale. Measurements show that for moderately stratified flows (for which FL 0.25) a minimum in the hill-induced surface-pressure perturbation occurs across the summit and this is accompanied by a maximum in the near-surface wind speed. In the more strongly stratified case (FL 0.25) the pressure field is more asymmetric and the lee-slope flow is generally stronger than on the windward slope. Such a flow pattern is qualitatively consistent with that predicted by stratified linear boundary-layer and gravity-wave theories. The near-surface momentum budget is analysed by evaluating the dominant terms in a Bernoulli equation suitable for turbulent flow. Measurements during periods of westerly flow are used to evaluate the dominant terms, and the equation is shown to hold to a reasonable approximation on the upwind slope of the hill and also on the downwind slope, away from the summit. Immediately downwind of the summit, however, the Bernoulli equation does not hold. Possible reasons for this, such as non-separated sheltering and flow separation, are discussed.

  3. Long Term Validation of Land Surface Temperature Retrieved from MSG/SEVIRI with Continuous in-Situ Measurements in Africa

    Directory of Open Access Journals (Sweden)

    Frank-M. Göttsche

    2016-05-01

    Full Text Available Since 2005, the Land Surface Analysis Satellite Application Facility (LSA SAF operationally retrieves Land Surface Temperature (LST for the Spinning Enhanced Visible and Infrared Imager (SEVIRI on board Meteosat Second Generation (MSG. The high temporal resolution of the Meteosat satellites and their long term availability since 1977 make their data highly valuable for climate studies. In order to ensure that the LSA SAF LST product continuously meets its target accuracy of 2 °C, it is validated with in-situ measurements from four dedicated LST validation stations. Three stations are located in highly homogenous areas in Africa (semiarid bush, desert, and Kalahari semi-desert and typically provide thousands of monthly match-ups with LSA SAF LST, which are used to perform seasonally resolved validations. An uncertainty analysis performed for desert station Gobabeb yielded an estimate of total in-situ LST uncertainty of 0.8 ± 0.12 °C. Ignoring rainy seasons, the results for the period 2009–2014 show that LSA SAF LST consistently meets its target accuracy: the highest mean root-mean-square error (RMSE for LSA SAF LST over the African stations was 1.6 °C while mean absolute bias was 0.1 °C. Nighttime and daytime biases were up to 0.7 °C but had opposite signs: when evaluated together, these partially compensated each other.

  4. EXAMINATION ABOUT INFLUENCE FOR PRECISION OF 3D IMAGE MEASUREMENT FROM THE GROUND CONTROL POINT MEASUREMENT AND SURFACE MATCHING

    Directory of Open Access Journals (Sweden)

    T. Anai

    2015-05-01

    Full Text Available As the 3D image measurement software is now widely used with the recent development of computer-vision technology, the 3D measurement from the image is now has acquired the application field from desktop objects as wide as the topography survey in large geographical areas. Especially, the orientation, which used to be a complicated process in the heretofore image measurement, can be now performed automatically by simply taking many pictures around the object. And in the case of fully textured object, the 3D measurement of surface features is now done all automatically from the orientated images, and greatly facilitated the acquisition of the dense 3D point cloud from images with high precision. With all this development in the background, in the case of small and the middle size objects, we are now furnishing the all-around 3D measurement by a single digital camera sold on the market. And we have also developed the technology of the topographical measurement with the air-borne images taken by a small UAV [1~5]. In this present study, in the case of the small size objects, we examine the accuracy of surface measurement (Matching by the data of the experiments. And as to the topographic measurement, we examine the influence of GCP distribution on the accuracy by the data of the experiments. Besides, we examined the difference of the analytical results in each of the 3D image measurement software. This document reviews the processing flow of orientation and the 3D measurement of each software and explains the feature of the each software. And as to the verification of the precision of stereo-matching, we measured the test plane and the test sphere of the known form and assessed the result. As to the topography measurement, we used the air-borne image data photographed at the test field in Yadorigi of Matsuda City, Kanagawa Prefecture JAPAN. We have constructed Ground Control Point which measured by RTK-GPS and Total Station. And we show the results

  5. Examination about Influence for Precision of 3d Image Measurement from the Ground Control Point Measurement and Surface Matching

    Science.gov (United States)

    Anai, T.; Kochi, N.; Yamada, M.; Sasaki, T.; Otani, H.; Sasaki, D.; Nishimura, S.; Kimoto, K.; Yasui, N.

    2015-05-01

    As the 3D image measurement software is now widely used with the recent development of computer-vision technology, the 3D measurement from the image is now has acquired the application field from desktop objects as wide as the topography survey in large geographical areas. Especially, the orientation, which used to be a complicated process in the heretofore image measurement, can be now performed automatically by simply taking many pictures around the object. And in the case of fully textured object, the 3D measurement of surface features is now done all automatically from the orientated images, and greatly facilitated the acquisition of the dense 3D point cloud from images with high precision. With all this development in the background, in the case of small and the middle size objects, we are now furnishing the all-around 3D measurement by a single digital camera sold on the market. And we have also developed the technology of the topographical measurement with the air-borne images taken by a small UAV [1~5]. In this present study, in the case of the small size objects, we examine the accuracy of surface measurement (Matching) by the data of the experiments. And as to the topographic measurement, we examine the influence of GCP distribution on the accuracy by the data of the experiments. Besides, we examined the difference of the analytical results in each of the 3D image measurement software. This document reviews the processing flow of orientation and the 3D measurement of each software and explains the feature of the each software. And as to the verification of the precision of stereo-matching, we measured the test plane and the test sphere of the known form and assessed the result. As to the topography measurement, we used the air-borne image data photographed at the test field in Yadorigi of Matsuda City, Kanagawa Prefecture JAPAN. We have constructed Ground Control Point which measured by RTK-GPS and Total Station. And we show the results of analysis made

  6. 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.

  7. Airborne spectral measurements of surface anisotropy during SCAR-B

    Science.gov (United States)

    Tsay, Si-Chee; King, Michael D.; Arnold, G. Thomas; Li, Jason Y.

    1998-12-01

    During the Smoke, Clouds, and Radiation-Brazil (SCAR-B) deployment, angular distributions of spectral reflectance for vegetated surfaces and smoke layers were measured using the scanning cloud absorption radiometer (CAR) mounted on the University of Washington C-131A research aircraft. The CAR contains 13 narrowband spectral channels between 0.3 and 2.3 μm with a 190° scan aperture (5° before zenith to 5° past nadir) and 1° instantaneous field of view. The bidirectional reflectance is obtained by flying a clockwise circular orbit above the surface, resulting in a ground track ˜3 km in diameter within about 2 min. Although the CAR measurements are contaminated by minor atmospheric effects, results show distinct spectral characteristics for various types of surfaces. Spectral bidirectional reflectances of three simple and well-defined surfaces are presented: cerrado (August 18, 1995) and dense forest (August 25, 1995), both measured in Brazil under nearly clear-sky conditions, and thick smoke layers over dense forest (September 6 and 11, 1995). The bidirectional reflectances of cerrado and dense forest revealed fairly symmetric patterns along the principal plane, with varying maximal strengths and widths spectrally in the backscattering direction. In the shortwave-infrared region the aerosol effect is very small due to low spectral optical depth. Also, these backscattering maxima can be seen on the bidirectional reflectance of smoke layer over dense forest. These detailed measurements of the angular distribution of spectral reflectance can be parameterized by a few independent variables and utilized to retrieve either surface characteristics or aerosol microphysical and optical properties (e.g., size distribution and single-scattering parameters), if proper physical and radiation models are used. The spectral-hemispherical albedo of these surfaces is obtained directly by integrating all angular measurements and is compared with the measured nadir reflectance

  8. 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).

  9. Hole-to-surface resistivity measurements at Gibson Dome (drill hole GD-1) Paradox basin, Utah

    Science.gov (United States)

    Daniels, J.J.

    1984-01-01

    Hole-to-surface resistivity measurements were made in a deep drill hole (GD-1), in San Juan County, Utah, which penetrated a sequence of sandstone, shale, and evaporite. These measurements were made as part of a larger investigation to study the suitability of an area centered around the Gibson Dome structure for nuclear waste disposal. The magnitude and direction of the total electric field resulting from a current source placed in a drill hole is calculated from potential difference measurements for a grid of closely-spaced stations. A contour map of these data provides a detailed map of the distribution of the electric field away from the drill hole. Computation of the apparent resistivity from the total electric field helps to interpret the data with respect to the ideal situation of a layered earth. Repeating the surface measurements for different source depths gives an indication of variations in the geoelectric section with depth. The quantitative interpretation of the field data at Gibson Dome was hindered by the pressure of a conductive borehole fluid. However, a qualitative interpretation of the field data indicates the geoelectric section around drill hole GD-1 is not perfectly layered. The geoelectric section appears to dip to the northwest, and contains anomalies in the resistivity distribution that may be representative of localized thickening or folding of the salt layers.

  10. Measurements of greenhouse gases at Beromünster tall-tower station in Switzerland

    Science.gov (United States)

    Ayalneh Berhanu, Tesfaye; Satar, Ece; Schanda, Rudiger; Nyfeler, Peter; Moret, Hanspeter; Brunner, Dominik; Oney, Brian; Leuenberger, Markus

    2016-06-01

    In order to constrain the regional flux of greenhouse gases, an automated measurement system was built on an old radio tower at Beromünster, Switzerland. The measurement system has been running since November 2012 as part of the Swiss greenhouse gases monitoring network (CarboCount-CH), which is composed of four measurement sites across the country. The Beromünster tall tower has five sampling lines with inlets at 12.5, 44.6, 71.5, 131.6, and 212.5 m above ground level, and it is equipped with a Picarro cavity ring-down spectrometer (CRDS) analyzer (G-2401), which continuously measures CO, CO2, CH4, and H2O. Sensors for detection of wind speed and direction, air temperature, barometric pressure, and humidity have also been installed at each height level. We have observed a non-negligible temperature effect in the calibration measurements, which was found to be dependent on the type of cylinder (steel or aluminum) as well as trace gas species (strongest for CO). From a target gas of known mixing ratio that has been measured once a day, we have calculated a long-term reproducibility of 2.79 ppb, 0.05 ppm, and 0.29 ppb for CO, CO2, and CH4, respectively, over 19 months of measurements. The values obtained for CO2 and CH4 are compliant with the WMO recommendations, while the value calculated for CO is higher than the recommendation. Since the installation of an air-conditioning system recently at the measurement cabin, we have acquired better temperature stability of the measurement system, but no significant improvement was observed in the measurement precision inferred from the target gas measurements. Therefore, it seems that the observed higher variation in CO measurements is associated with the instrumental noise, compatible with the precision provided by the manufacturer.

  11. Seasonal changes in peatland surface elevation recorded at GPS stations in the Red Lake Peatlands, northern Minnesota, USA

    Science.gov (United States)

    Reeve, A.S.; Glaser, P.H.; Rosenberry, Donald O.

    2013-01-01

    Northern peatlands appear to hold large volumes of free-phase gas (e.g., CH4 and CO2), which has been detected by surface deformations, pore pressure profiles, and electromagnetic surveys. Determining the gas content and its impact in peat is challenging because gas storage depends on both the elastic properties of the peat matrix and the buoyant forces exerted by pore fluids. We therefore used a viscoelastic deformation model to estimate these variables by adjusting model runs to reproduce observed changes in peat surface elevation within a 1300 km2 peatland. A local GPS network documented significant changes in surface elevations throughout the year with the greatest vertical displacements associated with rapid changes in peat water content and unloadings due to melting of the winter snowpack. These changes were coherent with changes in water table elevation and also abnormal pore pressure changes measured by nests of instrumented piezometers. The deformation model reproduced these changes when the gas content was adjusted to 10% of peat volume, and Young's modulus was varied between 5 and 100 kPa as the peat profile shifted from tension to compression. In contrast, the model predicted little peat deformation when the gas content was 3% or lower. These model simulations are consistent with previous estimates of gas volume in northern peatlands and suggest an upper limit of gas storage controlled by the elastic moduli of the peat fabric.

  12. 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.

  13. 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.

  14. Determination of Measurement Points in Urban Environments for Assessment of Maximum Exposure to EMF Associated with a Base Station

    Directory of Open Access Journals (Sweden)

    Agostinho Linhares

    2014-01-01

    Full Text Available A base station (BS antenna operates in accordance with the established exposure limits if the values of electromagnetic fields (EMF measured in points of maximum exposure are below these limits. In the case of BS in open areas, the maximum exposure to EMF probably occurs in the antenna’s boresight direction, from a few tens to a few hundred meters away. This is not a typical scenery for urban environments. However, in the line of sight (LOS situation, the region of maximum exposure can still be analytically estimated with good results. This paper presents a methodology for the choice of measurement points in urban areas in order to assess compliance with the limits for exposure to EMF.

  15. Characterization of a complex near-surface structure using well logging and passive seismic measurements

    Science.gov (United States)

    Benjumea, Beatriz; Macau, Albert; Gabàs, Anna; Figueras, Sara

    2016-04-01

    We combine geophysical well logging and passive seismic measurements to characterize the near-surface geology of an area located in Hontomin, Burgos (Spain). This area has some near-surface challenges for a geophysical study. The irregular topography is characterized by limestone outcrops and unconsolidated sediments areas. Additionally, the near-surface geology includes an upper layer of pure limestones overlying marly limestones and marls (Upper Cretaceous). These materials lie on top of Low Cretaceous siliciclastic sediments (sandstones, clays, gravels). In any case, a layer with reduced velocity is expected. The geophysical data sets used in this study include sonic and gamma-ray logs at two boreholes and passive seismic measurements: three arrays and 224 seismic stations for applying the horizontal-to-vertical amplitude spectra ratio method (H/V). Well-logging data define two significant changes in the P-wave-velocity log within the Upper Cretaceous layer and one more at the Upper to Lower Cretaceous contact. This technique has also been used for refining the geological interpretation. The passive seismic measurements provide a map of sediment thickness with a maximum of around 40 m and shear-wave velocity profiles from the array technique. A comparison between seismic velocity coming from well logging and array measurements defines the resolution limits of the passive seismic techniques and helps it to be interpreted. This study shows how these low-cost techniques can provide useful information about near-surface complexity that could be used for designing a geophysical field survey or for seismic processing steps such as statics or imaging.

  16. 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.

  17. 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.

  18. Quantitative nanoscale surface voltage measurement on organic semiconductor blends

    International Nuclear Information System (INIS)

    Cuenat, Alexandre; Muñiz-Piniella, Andrés; Muñoz-Rojo, Miguel; Murphy, Craig E; Tsoi, Wing C

    2012-01-01

    We report on the validation of a method based on Kelvin probe force microscopy (KPFM) able to measure the different phases and the relative work function of polymer blend heterojunctions at the nanoscale. The method does not necessitate complex ultra-high vacuum setup. The quantitative information that can be extracted from the topography and the Kelvin probe measurements is critically analysed. Surface voltage difference can be observed at the nanoscale on poly(3-hexyl-thiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM) blends and dependence on the annealing condition and the regio-regularity of P3HT is observed. (paper)

  19. 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

  20. Modeling of mean radiant temperature based on comparison of airborne remote sensing data with surface measured data

    Science.gov (United States)

    Chen, Yu-Cheng; Chen, Chih-Yu; Matzarakis, Andreas; Liu, Jin-King; Lin, Tzu-Ping

    2016-06-01

    Assessment of outdoor thermal comfort is becoming increasingly important due to the urban heat island effect, which strongly affects the urban thermal environment. The mean radiant temperature (Tmrt) quantifies the effect of the radiation environment on humans, but it can only be estimated based on influencing parameters and factors. Knowledge of Tmrt is important for quantifying the heat load on human beings, especially during heat waves. This study estimates Tmrt using several methods, which are based on climatic data from a traditional weather station, microscale ground surface measurements, land surface temperature (LST) and light detection and ranging (LIDAR) data measured using airborne devices. Analytical results reveal that the best means of estimating Tmrt combines information about LST and surface elevation information with meteorological data from the closest weather station. The application in this method can eliminate the inconvenience of executing a wide range ground surface measurement, the insufficient resolution of satellite data and the incomplete data of current urban built environments. This method can be used to map a whole city to identify hot spots, and can be contributed to understanding human biometeorological conditions quickly and accurately.

  1. Measuring personal exposure from 900MHz mobile phone base stations in Australia and Belgium using a novel personal distributed exposimeter.

    Science.gov (United States)

    Bhatt, Chhavi Raj; Thielens, Arno; Redmayne, Mary; Abramson, Michael J; Billah, Baki; Sim, Malcolm R; Vermeulen, Roel; Martens, Luc; Joseph, Wout; Benke, Geza

    2016-01-01

    The aims of this study were to: i) measure personal exposure in the Global System for Mobile communications (GSM) 900MHz downlink (DL) frequency band with two systems of exposimeters, a personal distributed exposimeter (PDE) and a pair of ExpoM-RFs, ii) compare the GSM 900MHz DL exposures across various microenvironments in Australia and Belgium, and iii) evaluate the correlation between the PDE and ExpoM-RFs measurements. Personal exposure data were collected using the PDE and two ExpoM-RFs simultaneously across 34 microenvironments (17 each in Australia and Belgium) located in urban, suburban and rural areas. Summary statistics of the electric field strengths (V/m) were computed and compared across similar microenvironments in Australia and Belgium. The personal exposures across urban microenvironments were higher than those in the rural or suburban microenvironments. Likewise, the exposure levels across the outdoor were higher than those for indoor microenvironments. The five highest median exposure levels were: city centre (0.248V/m), bus (0.124V/m), railway station (0.105V/m), mountain/forest (rural) (0.057V/m), and train (0.055V/m) [Australia]; and bicycle (urban) (0.238V/m), tram station (0.238V/m), city centre (0.156V/m), residential outdoor (urban) (0.139V/m) and park (0.124V/m) [Belgium]. Exposures in the GSM900 MHz frequency band across most of the microenvironments in Australia were significantly lower than the exposures across the microenvironments in Belgium. Overall correlations between the PDE and the ExpoM-RFs measurements were high. The measured exposure levels were far below the general public reference levels recommended in the guidelines of the ICNIRP and the ARPANSA. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Annual variations in GPS-measured vertical displacements near Upernavik Isstrøm (Greenland) and contributions from surface mass loading

    DEFF Research Database (Denmark)

    Liu, Lin; Khan, Shfaqat Abbas; van Dam, Tonie

    2017-01-01

    variability. Here we examine the annual changes of the vertical displacements measured at two GPS stations (SRMP and UPVK) near Upernavik Isstrøm in western Greenland. We model elastic loading displacements due to various surface mass loading including three non-ice components: atmospheric pressure, ocean...

  3. 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...... 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...... reliable for ≈50% of participants. Although using sEMG to assess swallowing musculature function is easier to perform clinically and more comfortable to patients than invasive measures, as the measurement of muscle activity using TMS is unreliable, the use of sEMG for this muscle group is not recommended...

  4. Photometric imaging in particle size measurement and surface visualization.

    Science.gov (United States)

    Sandler, Niklas

    2011-09-30

    The aim of this paper is to give an insight into photometric particle sizing approaches, which differ from the typical particle size measurement of dispersed particles. These approaches can often be advantageous especially for samples that are moist or cohesive, when dispersion of particles is difficult or sometimes impossible. The main focus of this paper is in the use of photometric stereo imaging. The technique allows the reconstruction of three-dimensional images of objects using multiple light sources in illumination. The use of photometric techniques is demonstrated in at-line measurement of granules and on-line measurement during granulation and dry milling. Also, surface visualization and roughness measurements are briefly discussed. Copyright © 2010 Elsevier B.V. All rights reserved.

  5. On-Orbit Measurement of Next Generation Space Solar Cell Technology on the International Space Station

    Science.gov (United States)

    Wolford, David S.; Myers, Matthew G.; Prokop, Norman F.; Krasowski, Michael J.; Parker, David S.; Cassidy, Justin C.; Davies, William E.; Vorreiter, Janelle O.; Piszczor, Michael F.; McNatt, Jeremiah S.

    2015-01-01

    Measurement is essential for the evaluation of new photovoltaic (PV) technology for space solar cells. NASA Glenn Research Center (GRC) is in the process of measuring several solar cells in a supplemental experiment on NASA Goddard Space Flight Center's (GSFC) Robotic Refueling Mission's (RRM) Task Board 4 (TB4). Four industry and government partners have provided advanced PV devices for measurement and orbital environment testing. The experiment will be on-orbit for approximately 18 months. It is completely self-contained and will provide its own power and internal data storage. Several new cell technologies including four- junction (4J) Inverted Metamorphic Multijunction (IMM) cells will be evaluated and the results compared to ground-based measurements.

  6. Trimble M3 1” and South Nts-362R Total Station Angle Measurement Accuracy Analysis

    Directory of Open Access Journals (Sweden)

    Oleniacz Grzegorz

    2017-03-01

    Full Text Available The main purpose of this study was to obtain information about the actual precision of angle measurements with two instruments (Trimble M3 1 "and South NTS-362R, realizable in given measurement conditions. This object is achieved by using a simplified method of testing instruments contained in the PN-ISO 17123-3 standard [1]. This is a continuation of research described in [2], carried out on the same test base, but this time in a different, less favorable field conditions. The use of the same instrument has created an opportunity to compare and analyze the measurement results. The scope of work includes the measurement and results preparation along with statistical processing of the obtained results for both instruments.

  7. Modeling and Measurement of Electromagnetic Fields Near LORAN-C and OMEGA Stations

    Science.gov (United States)

    1987-06-15

    high-speed computers. This approach to field strength determination has several advantages and is often used along with measurements in a...Further from the feed, advantage was taken of the symmetry of the antenna systems. Field strengths near monopole antennas are cylindrically symmetric...was extended a short distnnce beyond the shield to create an electric field probe. Magnetic fields were measured using the Alltech loop, which

  8. Experience in ultrasonic gap measurement between calandria tubes and liquid injection shutdown systems nozzles in Bruce Nuclear Generating Station

    International Nuclear Information System (INIS)

    Abucay, R.C.; Mahil, K.S.; Goszczynski, J.J.

    1995-01-01

    The gaps between calandria tubes (CT) and Liquid Injection Shutdown System (LISS) nozzles at the Bruce Nuclear Generating Station ''A'' (Bruce A) are known to decrease with time due to radiation induced creep/sag of the calandria tubes. If this gap decreases to a point where the calandria tubes come into contact with the LISS nozzle, the calandria tubes could fail as a result of fretting damage. Proximity measurements were needed to verify the analytical models and ensure that CT/LISS nozzle contact does not occur earlier than predicted. The technique used was originally developed at Ontario Hydro Technologies (formerly Ontario Hydro Research Division) in the late seventies and put into practical use by Research and Productivity Council (RPC) of New Brunswick, who carried out similar measurements at Point Lepreau NGS in 1989 and 1991. The gap measurement was accomplished y inserting an inspection probe, containing four ultrasonic transducers (2 to measure gaps and 2 to check for probe tilt) and a Fredericks electrolytic potentiometer as a probe rotational sensor, inside LISS Nozzle number-sign 7. The ultrasonic measurements were fed to a system computer that was programmed to convert the readings into fully compensated gaps, taking into account moderator heavy water temperature and probe tilt. Since the measured gaps were found to be generally larger than predicted, the time to CT/LISS nozzle contact is now being re-evaluated and the planned LISS nozzle replacement will likely be deferred, resulting in considerable savings

  9. MEASUREMENTS OF THE CONFINEMENT LEAKTIGHTNESS AT THE KOLA NUCLEAR POWER STATION (UNIT 2) IN RUSSIA

    International Nuclear Information System (INIS)

    GREENE, G.A.; GUPPY, J.G.

    1998-01-01

    This is the final report on the INSP project entitled, ''Kola Confinement Leaktightness'' conducted by BNL under the authorization of Project Work Plan WBS 1.2.2.1. This project was initiated in February 1993 to assist the Russians to reduce risks associated with the continued operation of older Soviet-designed nuclear power plants, specifically the Kola VVER-440/230 Units 1 and 2, through upgrades in the confinement performance to reduce the uncontrolled leakage rate. The major technical objective of this-project was to improve the leaktightness of the Kola NPP VVER confinement boundaries, through the application of a variety of sealants to penetrations, doors and hatches, seams and surfaces, to the extent that current technology permitted. A related objective was the transfer, through training of Russian staff, of the materials application procedures to the staff of the Kola NPP. This project was part of an overall approach to minimizing uncontrolled releases from the Kola NPP VVER440/230s in the event of a serious accident, and to thereby significantly mitigate the consequences of such an accident. The US provided materials, application technology, and applications equipment for application of sealant materials, surface coatings, potting materials and gaskets, to improve the confinement leaktightness of the Kola VVER-440/23Os. The US provided for training of Russian personnel in the applications technology

  10. MEASUREMENTS OF THE CONFINEMENT LEAKTIGHTNESS AT THE KOLA NUCLEAR POWER STATION (UNIT 2) IN RUSSIA

    Energy Technology Data Exchange (ETDEWEB)

    GREENE,G.A.; GUPPY,J.G.

    1998-08-01

    This is the final report on the INSP project entitled, ``Kola Confinement Leaktightness'' conducted by BNL under the authorization of Project Work Plan WBS 1.2.2.1. This project was initiated in February 1993 to assist the Russians to reduce risks associated with the continued operation of older Soviet-designed nuclear power plants, specifically the Kola VVER-440/230 Units 1 and 2, through upgrades in the confinement performance to reduce the uncontrolled leakage rate. The major technical objective of this-project was to improve the leaktightness of the Kola NPP VVER confinement boundaries, through the application of a variety of sealants to penetrations, doors and hatches, seams and surfaces, to the extent that current technology permitted. A related objective was the transfer, through training of Russian staff, of the materials application procedures to the staff of the Kola NPP. This project was part of an overall approach to minimizing uncontrolled releases from the Kola NPP VVER440/230s in the event of a serious accident, and to thereby significantly mitigate the consequences of such an accident. The US provided materials, application technology, and applications equipment for application of sealant materials, surface coatings, potting materials and gaskets, to improve the confinement leaktightness of the Kola VVER-440/23Os. The US provided for training of Russian personnel in the applications technology.

  11. Comparisons Between Model Predictions and Spectral Measurements of Charged and Neutral Particles on the Martian Surface

    Science.gov (United States)

    Kim, Myung-Hee Y.; Cucinotta, Francis A.; Zeitlin, Cary; Hassler, Donald M.; Ehresmann, Bent; Rafkin, Scot C. R.; Wimmer-Schweingruber, Robert F.; Boettcher, Stephan; Boehm, Eckart; Guo, Jingnan; hide

    2014-01-01

    Detailed measurements of the energetic particle radiation environment on the surface of Mars have been made by the Radiation Assessment Detector (RAD) on the Curiosity rover since August 2012. RAD is a particle detector that measures the energy spectrum of charged particles (10 to approx. 200 MeV/u) and high energy neutrons (approx 8 to 200 MeV). The data obtained on the surface of Mars for 300 sols are compared to the simulation results using the Badhwar-O'Neill galactic cosmic ray (GCR) environment model and the high-charge and energy transport (HZETRN) code. For the nuclear interactions of primary GCR through Mars atmosphere and Curiosity rover, the quantum multiple scattering theory of nuclear fragmentation (QMSFRG) is used. For describing the daily column depth of atmosphere, daily atmospheric pressure measurements at Gale Crater by the MSL Rover Environmental Monitoring Station (REMS) are implemented into transport calculations. Particle flux at RAD after traversing varying depths of atmosphere depends on the slant angles, and the model accounts for shielding of the RAD "E" dosimetry detector by the rest of the instrument. Detailed comparisons between model predictions and spectral data of various particle types provide the validation of radiation transport models, and suggest that future radiation environments on Mars can be predicted accurately. These contributions lend support to the understanding of radiation health risks to astronauts for the planning of various mission scenarios

  12. Direct measurements of employees involved in the Fukushima Daiichi Nuclear Power Station accident for internal dose estimates. JAEA's experiences

    Energy Technology Data Exchange (ETDEWEB)

    Kurihara, Osamu; Kanai, Katsuta; Nakagawa, Takahiro; Takada, Chie; Momose, Takumaro; Furuta, Sadaaki [Japan Atomic Energy Agency, Nuclear Fuel Cycle Engineering Laboratories, Tokai, Ibaraki (Japan)

    2012-11-15

    Japan Atomic Energy Agency (JAEA) performed internal dose measurements of employees involved in the Fukushima Daiichi nuclear power station accident. Nuclear Fuel Cycle Engineering Laboratories (NFCEL), one of the JAEA's core centers, examined 560 of these employees by direct (in vivo) measurements during the period from April 20 to August 5 in 2011. These measurements consisted of whole-body counting for radiocesium and thyroid counting for radioiodine. The whole-body counting was conducted with two types of whole-body counters (WBCs): a standing-type WBC with two large NaI(Tl) detectors (Fastscan{sup TM}, Canberra Inc.) and a chair-type WBC with HPGe detectors (GC5021, Canberra Inc.) installed in a shielded chamber made of 20-cm-thick steel. The thyroid counting was mainly performed using one of the two HPGe detectors equipped with the chair-type WBC. The subjects examined in this work were divided into two groups: Group 1 was the first 39 subjects who were measured up to June 17, 2011 and Group 2 was the remaining 521 subjects who were measured on and after June 18, 2011. The performance of our direct measurements was validated by comparing measurement results of the Group 1 subjects using two different methods (e.g., the standing-type WBC vs. the chair-type WBC). Tentative internal dose estimates of the subjects of Group 1 were also performed based on the assumption of a single intake scenario on either March 12, when the first hydrogen explosion occurred at the station or the first day of work after the accident. It was found that the contribution of {sup 131}I to the total internal dose greatly exceeded those of {sup 134}Cs and {sup 137}Cs, the other major nuclides detected in the measurements. The maximum committed effective dose (CED) was found in a male subject whose thyroid content of {sup 131}I was 9760 Bq on May 23, 2011; the CED of this subject was estimated to be 600 mSv including a small contribution of {sup 134}Cs and {sup 137}Cs. The typical

  13. Surface renewal: an advanced micrometeorological method for measuring and processing field-scale energy flux density data.

    Science.gov (United States)

    McElrone, Andrew J; Shapland, Thomas M; Calderon, Arturo; Fitzmaurice, Li; Paw U, Kyaw Tha; Snyder, Richard L

    2013-12-12

    Advanced micrometeorological methods have become increasingly important in soil, crop, and environmental sciences. For many scientists without formal training in atmospheric science, these techniques are relatively inaccessible. Surface renewal and other flux measurement methods require an understanding of boundary layer meteorology and extensive training in instrumentation and multiple data management programs. To improve accessibility of these techniques, we describe the underlying theory of surface renewal measurements, demonstrate how to set up a field station for surface renewal with eddy covariance calibration, and utilize our open-source turnkey data logger program to perform flux data acquisition and processing. The new turnkey program returns to the user a simple data table with the corrected fluxes and quality control parameters, and eliminates the need for researchers to shuttle between multiple processing programs to obtain the final flux data. An example of data generated from these measurements demonstrates how crop water use is measured with this technique. The output information is useful to growers for making irrigation decisions in a variety of agricultural ecosystems. These stations are currently deployed in numerous field experiments by researchers in our group and the California Department of Water Resources in the following crops: rice, wine and raisin grape vineyards, alfalfa, almond, walnut, peach, lemon, avocado, and corn.

  14. Tritium enrichment and measurement of groundwater in western nile delta and greater cairo water stations

    International Nuclear Information System (INIS)

    Salem, W.M.M.M.

    1990-01-01

    Water is the limiting factor for land reclamation plans and establishing new communities . Therefore water management policy and the exploitation of every possible water resources are very important in order to cope with the growing population. Groundwater is a very important water resource for agricultural and drinking purposes. However, the wise water management policy should take into consideration that groundwater could be either recharge able or not depending on the connection of the aquifer with surface water resources . If water is not recharged; then it is subject to be exhausted after a certain time period. Even if water is recharge able the rate of water pumping should not exceed the water recharge rate. Therefore, the basic questions of the water origin and recharge time should be answered before starting any land reclamation or drinking water project

  15. Measuring human remains in the field: Grid technique, total station, or MicroScribe?

    Czech Academy of Sciences Publication Activity Database

    Sládek, Vladimír; Galeta, P.; Sosna, D.

    2012-01-01

    Roč. 221, 1-3 (2012), s. 16-22 ISSN 0379-0738 Institutional support: RVO:68081766 Keywords : Excavation * Field anthropology * Human skeleton * Measuring error Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 2.307, year: 2012

  16. 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.

  17. 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.

  18. Radiotherapy high energy surface dose measurements: effects of chamber polarity

    International Nuclear Information System (INIS)

    Cheung, T.; Yu, P.K.N.; Butson, M.J.; Cancer Services, Wollongong, NSW

    2004-01-01

    Full text: The effects of chamber polarity have been investigated for the measurement of 6MV and 18MV x-ray surface dose using a parallel plate ionization chamber. Results have shown that a significant difference in measured ionization is recorded between to polarities at 6MV and 18MV at the phantom surface. A polarity ratio ranging from 1 062 to 1 005 is seen for 6MV x-rays at the phantom surface for field sizes 5cm x 5cm to 40cm x 40cm when comparing positive to negative polarity. These ratios range from 1.024 to 1.004 for 18MV x-rays with the same field sizes. When these charge reading are compared to the D max readings of the same polarity it is found that these polarity effects are minimal for the calculation of percentage dose results with variations being less than 1% of maximum. Copyright (2004) Australasian College of Physical Scientists and Engineers in Medicine

  19. 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

  20. Measurement of solar radiation at the Earth's surface

    Science.gov (United States)

    Bartman, F. L.

    1982-01-01

    The characteristics of solar energy arriving at the surface of the Earth are defined and the history of solar measurements in the United States presented. Radiation and meteorological measurements being made at solar energy meteorological research and training sites and calibration procedures used there are outlined. Data illustrating the annual variation in daily solar radiation at Ann Arbor, Michigan and the diurnal variation in radiation at Albuquerque, New Mexico are presented. Direct normal solar radiation received at Albuquerque is contrasted with that received at Maynard, Massachusetts. Average measured global radiation for a period of one year for four locations under clear skies, 50% cloud cover, and 100% cloud cover is given and compared with the solar radiation at the top of the atmosphere. The May distribution of mean daily direct solar radiation and mean daily global solar radiation over the United States is presented. The effects of turbidity on the direct and circumsolar radiation are shown.

  1. Monitoring of Cyclic Steam Stimulation by Inversion of Surface Tilt Measurements

    Science.gov (United States)

    Maharramov, M.; Zoback, M. D.

    2014-12-01

    Temperature and pressure changes associated with the cyclic steam simulation (CSS) used in heavy oil production from sands are accompanied by significant deformation. Inversion of geomechanical data may provide a potentially powerful reservoir monitoring tool where geomechanical effects are significant. Induced pore pressure changes can be inverted from measurable surface deformations by solving an inverse problem of poroelasticity. In this work, we apply this approach to estimating pore pressure changes from surface tilt measurements at a heavy oil reservoir undergoing cyclic steam simulation. Steam was injected from November 2007 through January 2008. Surface tilt measurements were collected from 25 surface tilt stations during this period. The injection ran in two overlapping phases: Phase 1 ran from the beginning of the injection though mid-December, and Phase 2 overlapped with Phase 1 and ran through the beginning of January. During Phase 1 steam was injected in the western part of the reservoir, followed by injection in the eastern part in Phase 2. The pore pressure evolution was inverted from daily tilt measurements using regularized constrained least squares fitting, the results are shown on the plot. Estimated induced pore pressure change (color scale), observed daily incremental tilts (green arrows) and modeled daily incremental tilts (red arrows) are shown in three panels corresponding to two and five weeks of injection, and the end of injection period. DGPS measurements available for a single location were used as an additional inversion constraint. The results indicate that the pore pressure increase in the reservoir follows the same pattern as the steam injection, from west to east. This qualitative behaviour is independent of the amount of regularization, indirectly validating our inversion approach. Patches of lower pressure appear to be stable with regard to regularization and may provide valuable insight into the efficiency of steam injection

  2. Power raise through improved reactor inlet header temperature measurement at Bruce A Nuclear Generation Station

    International Nuclear Information System (INIS)

    Basu, S.; Bruggemn, D.

    1997-01-01

    Reactor Inlet Header (RIH) temperature has become a factor limiting the performance of the Ontario Hydro Bruce A units. Specifically, the RIH temperature is one of several parameters that is preventing the Bruce A units from returning to 94% power operation. RIH temperature is one of several parameters which affect the critical heat flux in the reactor channel, and hence the integrity of the fuel. Ideally, RIH temperature should be lowered, but this cannot be done without improving the heat transfer performance of the boilers and feedwater pre-heaters. Unfortunately, the physical performance of the boilers and pre-heaters has decayed and continues to decay over time and as a result the RIH temperature has been rising and approaching its defined limit. With an understanding of the current RIH temperature measurement loop and methods available to improve it, a solution to reduce the measurement uncertainty is presented

  3. Extremely low frequency magnetic field measurements in buildings with transformer stations in Switzerland.

    Science.gov (United States)

    Röösli, Martin; Jenni, Daniela; Kheifets, Leeka; Mezei, Gabor

    2011-08-15

    The aim of this study was to evaluate an exposure assessment method that classifies apartments in three exposure categories of extremely low frequency magnetic fields (ELF-MF) based on the location of the apartment relative to the transformer room. We completed measurements in 39 apartments in 18 buildings. In each room of the apartments ELF-MF was concurrently measured with 5 to 6 EMDEX II meters for 10 min. Measured arithmetic mean ELF-MF was 0.59 μT in 8 apartments that were fully adjacent to a transformer room, either directly above the transformer or touching the transformer room wall-to-wall. In apartments that only partly touched the transformer room at corners or edges, average ELF-MF level was 0.14 μT. Average exposure in the remaining apartments was 0.10 μT. Kappa coefficient for exposure classification was 0.64 (95%-CI: 0.45-0.82) if only fully adjacent apartments were considered as highly exposed (>0.4 μT). We found a distinct ELF-MF exposure gradient in buildings with transformer. Exposure classification based on the location of the apartment relative to the transformer room appears feasible. Such an approach considerably reduces effort for exposure assessment and may be used to eliminate selection bias in future epidemiologic studies. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Measurements of flux surfaces in the ATF torsatron

    International Nuclear Information System (INIS)

    England, A.C.; Colchin, R.J.; Harris, J.H.; Hillis, D.L.; Jernigan, T.C.; Anderson, F.S.B.

    1989-01-01

    Flux surfaces in the advanced toroidal facility (ATF) torsatron have been measured using electron-beam techniques. The beam was injected toroidally and impinged on a phosphor-coated screen located ∼ 180 degrees from the gun. The gun was mounted on a drive mechanism that enabled the beam to scan the entire cross section of the last closed flux surface in ATF. The screen material was st. steel, coated with ZnO:Zn (P-15 or P-24) phosphor, and the transparency was ∼ 90%. The emitted light was detected with an image-intensified CCD camera that viewed the mesh through a nearby port. The images were displayed directly on a TV monitor and stored on video tape. Frames from the video tape were transferred to a computer, where the image was enhanced and transformed to remove spatial distortions due to the lens and the viewing angle of the camera

  5. 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.

  6. BOREAS RSS-20 POLDER C-130 Measurements of Surface BRDF

    Science.gov (United States)

    Leroy, Marc; Hall, Forrest G. (Editor); Nickerson, Jaime (Editor); Smith, David E. (Technical Monitor)

    2000-01-01

    This Boreal Ecosystem-Atmosphere Study (BOREAS) Remote Sensing Science (RSS)-20 data set contains measurements of surface bidirectional reflectance distribution function (BRDF) made by the polarization and Directionality of Earth reflectances (POLDER) instrument over several surface types (pine, spruce, fen) of the BOREAS southern study area (SSA) during the 1994 intensive field campaigns (IFCs). Single-point BRDF values were acquired either from the NASA Ames Research Center (ARC) C-130 aircraft or from a NASA Wallops Flight Facility (WFF) helicopter. A related data set collected from the helicopter platform is available as is POLDER imagery acquired from the C-130. The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884) or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  7. Examination of a measuring method for fallout radioactivity released by the accident of the Fukushima Dai-ichi NPS. Surface contamination measurement

    International Nuclear Information System (INIS)

    Yoshii, Taiki; Kawasaki, Satoru

    2013-08-01

    Radioactive nuclides were released in the atmosphere by the accident of TEPCO's Fukushima Dai-ichi Nuclear Power Station in March, 2011, and they are detected on the materials that had no artificial radioactive nuclides before the accident. Confronted with this situation, NISA issued a guideline titled 'A guideline regarding treatment of materials in nuclear facilities considering the influence of fallout released from the accident of TEPCO's Fukushima Dai-ichi Nuclear Power Station' on March 30, 2012. Nuclear Regulatory Authority refers to applying the existing bylaw until the time to make decision of the updated bylaw. The guideline shows that after judging whether there is the influence of fallout or not, the conventional clearance and NR systems can be used when there is no influence of fallout. On the other hand, the special treatment is required when it is judged that there is the influence. This report describes a specific example of measuring method to evaluate the influence of fallout, in case of surface contamination. This report focused surface contamination of flat object as target. Preliminary investigation shows that the distribution of surface contamination due to fallout is near to lognormal distribution. Therefore, the sampling measurement can be adopted. The average surface contamination of target is decided from sampling data by using 90% upper confidence limit of Chebyshev inequality. Also, the minimum sampling number is decided. The evaluation of the influence of fallout is judged from the result of surface contamination measurement, weight of target and surface area of target. (author)

  8. 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.

  9. Electron and Positron Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station

    CERN Document Server

    Aguilar, M; Alvino, A; Ambrosi, G; Andeen, K; Arruda, L; Attig, N; Azzarello, P; Bachlechner, A; Barao, F; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Battarbee, M; Battiston, R; Bazo, J; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Bertucci, B; Bigongiari, G; Bindi, V; Bizzaglia, S; Bizzarri, M; Boella, G; de Boer, W; Bollweg, K; Bonnivard, V; Borgia, B; Borsini, S; Boschini, M J; Bourquin, M; Burger, J; Cadoux, F; Cai, X D; Capell, M; Caroff, S; Casaus, J; Cascioli, V; Castellini, G; Cernuda, I; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, H; Cheng, G M; Chen, H S; Cheng, L; Chikanian, A; Chou, H Y; Choumilov, E; Choutko, V; Chung, C H; Clark, C; Clavero, R; Coignet, G; Consolandi, C; Contin, A; Corti, C; Coste, B; Cui, Z; Dai, M; Delgado, C; Della Torre, S; Demirköz, M B; Derome, L; Di Falco, S; Di Masso, L; Dimiccoli, F; Díaz, C; von Doetinchem, P; Du, W J; Duranti, M; D’Urso, D; Eline, A; Eppling, F J; Eronen, T; Fan, Y Y; Farnesini, L; Feng, J; Fiandrini, E; Fiasson, A; Finch, E; Fisher, P; Galaktionov, Y; Gallucci, G; García, B; García-López, R; Gast, H; Gebauer, I; Gervasi, M; Ghelfi, A; Gillard, W; Giovacchini, F; Goglov, P; Gong, J; Goy, C; Grabski, V; Grandi, D; Graziani, M; Guandalini, C; Guerri, I; Guo, K H; Habiby, M; Haino, S; Han, K C; He, Z H; Heil, M; Hoffman, J; Hsieh, T H; Huang, Z C; Huh, C; Incagli, M; Ionica, M; Jang, W Y; Jinchi, H; Kanishev, K; Kim, G N; Kim, K S; Kirn, Th; Kossakowski, R; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; Kunz, S; La Vacca, G; Laudi, E; Laurenti, G; Lazzizzera, I; Lebedev, A; Lee, H T; Lee, S C; Leluc, C; Li, H L; Li, J Q; Li, Q; Li, Q; Li, T X; Li, W; Li, Y; Li, Z H; Li, Z Y; Lim, S; Lin, C H; Lipari, P; Lippert, T; Liu, D; Liu, H; Lomtadze, T; Lu, M J; Lu, Y S; Luebelsmeyer, K; Luo, F; Luo, J Z; Lv, S S; Majka, R; Malinin, A; Mañá, C; Marín, J; Martin, T; Martínez, G; Masi, N; Maurin, D; Menchaca-Rocha, A; Meng, Q; Mo, D C; Morescalchi, L; Mott, P; Müller, M; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Obermeier, A; Oliva, A; Orcinha, M; Palmonari, F; Palomares, C; Paniccia, M; Papi, A; Pedreschi, E; Pensotti, S; Pereira, R; Pilo, F; Piluso, A; Pizzolotto, C; Plyaskin, V; Pohl, M; Poireau, V; Postaci, E; Putze, A; Quadrani, L; Qi, X M; Rancoita, P G; Rapin, D; Ricol, J S; Rodríguez, I; Rosier-Lees, S; Rozhkov, A; Rozza, D; Sagdeev, R; Sandweiss, J; Saouter, P; Sbarra, C; Schael, S; Schmidt, S M; Schuckardt, D; Schulz von Dratzig, A; Schwering, G; Scolieri, G; Seo, E S; Shan, B S; Shan, Y H; Shi, J Y; Shi, X Y; Shi, Y M; Siedenburg, T; Son, D; Spada, F; Spinella, F; Sun, W; Sun, W H; Tacconi, M; Tang, C P; Tang, X W; Tang, Z C; Tao, L; Tescaro, D; Ting, Samuel C C; Ting, S M; Tomassetti, N; Torsti, J; Türkoğlu, C; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vaurynovich, S; Vecchi, M; Velasco, M; Vialle, J P; Wang, L Q; Wang, Q L; Wang, R S; Wang, X; Wang, Z X; Weng, Z L; Whitman, K; Wienkenhöver, J; Wu, H; Xia, X; Xie, M; Xie, S; Xiong, R Q; Xin, G M; Xu, N S; Xu, W; Yan, Q; Yang, J; Yang, M; Ye, Q H; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, J H; Zhang, M T; Zhang, X B; Zhang, Z; Zheng, Z M; Zhuang, H L; Zhukov, V; Zichichi, A; Zimmermann, N; Zuccon, P; Zurbach, C

    2014-01-01

    Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ∼30  GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.

  10. Electron and Positron Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station

    Science.gov (United States)

    Aguilar, M.; Aisa, D.; Alvino, A.; Ambrosi, G.; Andeen, K.; Arruda, L.; Attig, N.; Azzarello, P.; Bachlechner, A.; Barao, F.; Barrau, A.; Barrin, L.; Bartoloni, A.; Basara, L.; Battarbee, M.; Battiston, R.; Bazo, J.; Becker, U.; Behlmann, M.; Beischer, B.; Berdugo, J.; Bertucci, B.; Bigongiari, G.; Bindi, V.; Bizzaglia, S.; Bizzarri, M.; Boella, G.; de Boer, W.; Bollweg, K.; Bonnivard, V.; Borgia, B.; Borsini, S.; Boschini, M. J.; Bourquin, M.; Burger, J.; Cadoux, F.; Cai, X. D.; Capell, M.; Caroff, S.; Casaus, J.; Cascioli, V.; Castellini, G.; Cernuda, I.; Cervelli, F.; Chae, M. J.; Chang, Y. H.; Chen, A. I.; Chen, H.; Cheng, G. M.; Chen, H. S.; Cheng, L.; Chikanian, A.; Chou, H. Y.; Choumilov, E.; Choutko, V.; Chung, C. H.; Clark, C.; Clavero, R.; Coignet, G.; Consolandi, C.; Contin, A.; Corti, C.; Coste, B.; Cui, Z.; Dai, M.; Delgado, C.; Della Torre, S.; Demirköz, M. B.; Derome, L.; Di Falco, S.; Di Masso, L.; Dimiccoli, F.; Díaz, C.; von Doetinchem, P.; Du, W. J.; Duranti, M.; D'Urso, D.; Eline, A.; Eppling, F. J.; Eronen, T.; Fan, Y. Y.; Farnesini, L.; Feng, J.; Fiandrini, E.; Fiasson, A.; Finch, E.; Fisher, P.; Galaktionov, Y.; Gallucci, G.; García, B.; García-López, R.; Gast, H.; Gebauer, I.; Gervasi, M.; Ghelfi, A.; Gillard, W.; Giovacchini, F.; Goglov, P.; Gong, J.; Goy, C.; Grabski, V.; Grandi, D.; Graziani, M.; Guandalini, C.; Guerri, I.; Guo, K. H.; Habiby, M.; Haino, S.; Han, K. C.; He, Z. H.; Heil, M.; Hoffman, J.; Hsieh, T. H.; Huang, Z. C.; Huh, C.; Incagli, M.; Ionica, M.; Jang, W. Y.; Jinchi, H.; Kanishev, K.; Kim, G. N.; Kim, K. S.; Kirn, Th.; Kossakowski, R.; Kounina, O.; Kounine, A.; Koutsenko, V.; Krafczyk, M. S.; Kunz, S.; La Vacca, G.; Laudi, E.; Laurenti, G.; Lazzizzera, I.; Lebedev, A.; Lee, H. T.; Lee, S. C.; Leluc, C.; Li, H. L.; Li, J. Q.; Li, Q.; Li, Q.; Li, T. X.; Li, W.; Li, Y.; Li, Z. H.; Li, Z. Y.; Lim, S.; Lin, C. H.; Lipari, P.; Lippert, T.; Liu, D.; Liu, H.; Lomtadze, T.; Lu, M. J.; Lu, Y. S.; Luebelsmeyer, K.; Luo, F.; Luo, J. Z.; Lv, S. S.; Majka, R.; Malinin, A.; Mañá, C.; Marín, J.; Martin, T.; Martínez, G.; Masi, N.; Maurin, D.; Menchaca-Rocha, A.; Meng, Q.; Mo, D. C.; Morescalchi, L.; Mott, P.; Müller, M.; Ni, J. Q.; Nikonov, N.; Nozzoli, F.; Nunes, P.; Obermeier, A.; Oliva, A.; Orcinha, M.; Palmonari, F.; Palomares, C.; Paniccia, M.; Papi, A.; Pedreschi, E.; Pensotti, S.; Pereira, R.; Pilo, F.; Piluso, A.; Pizzolotto, C.; Plyaskin, V.; Pohl, M.; Poireau, V.; Postaci, E.; Putze, A.; Quadrani, L.; Qi, X. M.; Rancoita, P. G.; Rapin, D.; Ricol, J. S.; Rodríguez, I.; Rosier-Lees, S.; Rozhkov, A.; Rozza, D.; Sagdeev, R.; Sandweiss, J.; Saouter, P.; Sbarra, C.; Schael, S.; Schmidt, S. M.; Schuckardt, D.; von Dratzig, A. Schulz; Schwering, G.; Scolieri, G.; Seo, E. S.; Shan, B. S.; Shan, Y. H.; Shi, J. Y.; Shi, X. Y.; Shi, Y. M.; Siedenburg, T.; Son, D.; Spada, F.; Spinella, F.; Sun, W.; Sun, W. H.; Tacconi, M.; Tang, C. P.; Tang, X. W.; Tang, Z. C.; Tao, L.; Tescaro, D.; Ting, Samuel C. C.; Ting, S. M.; Tomassetti, N.; Torsti, J.; Türkoǧlu, C.; Urban, T.; Vagelli, V.; Valente, E.; Vannini, C.; Valtonen, E.; Vaurynovich, S.; Vecchi, M.; Velasco, M.; Vialle, J. P.; Wang, L. Q.; Wang, Q. L.; Wang, R. S.; Wang, X.; Wang, Z. X.; Weng, Z. L.; Whitman, K.; Wienkenhöver, J.; Wu, H.; Xia, X.; Xie, M.; Xie, S.; Xiong, R. Q.; Xin, G. M.; Xu, N. S.; Xu, W.; Yan, Q.; Yang, J.; Yang, M.; Ye, Q. H.; Yi, H.; Yu, Y. J.; Yu, Z. Q.; Zeissler, S.; Zhang, J. H.; Zhang, M. T.; Zhang, X. B.; Zhang, Z.; Zheng, Z. M.; Zhuang, H. L.; Zhukov, V.; Zichichi, A.; Zimmermann, N.; Zuccon, P.; Zurbach, C.; AMS Collaboration

    2014-09-01

    Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ˜30 GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.

  11. 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 limits of the range in reaction rate, which can be Studied are estimated. (c) 2005 Elsevier B.V. All rights reserved.......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...... limit for the lateral resolution of the measurement, and that a flow rate of the order of 240 (ml/min)(n) is sufficient to achieve this resolution. The sensitivity is reasonable also with high flow rates, due to the presence of a pocket of stagnant gas under the tip of the capillary. Furthermore...

  12. Testing of environmental radiation monitors using the Risø low-level radiation measurement stations

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.

    2000-01-01

    June, 1999. The chief aims of such experiments are to allow the participants to check their home calibrations of their detectors and to compare the responses of the individual environmental radiation measurement systems used in the different EU member states and making a link between the different...... a simulation of a radioactive plume passing over the monitors during a certain time was made using a specially designed source set up in the field that was able to vary the air kerma rate from low activity Cs-137 sources additional to the natural air kerma rate. It is demonstrated that a typical environmental...

  13. Surface Fitting for Quasi Scattered Data from Coordinate Measuring Systems.

    Science.gov (United States)

    Mao, Qing; Liu, Shugui; Wang, Sen; Ma, Xinhui

    2018-01-13

    Non-uniform rational B-spline (NURBS) surface fitting from data points is wildly used in the fields of computer aided design (CAD), medical imaging, cultural relic representation and object-shape detection. Usually, the measured data acquired from coordinate measuring systems is neither gridded nor completely scattered. The distribution of this kind of data is scattered in physical space, but the data points are stored in a way consistent with the order of measurement, so it is named quasi scattered data in this paper. Therefore they can be organized into rows easily but the number of points in each row is random. In order to overcome the difficulty of surface fitting from this kind of data, a new method based on resampling is proposed. It consists of three major steps: (1) NURBS curve fitting for each row, (2) resampling on the fitted curve and (3) surface fitting from the resampled data. Iterative projection optimization scheme is applied in the first and third step to yield advisable parameterization and reduce the time cost of projection. A resampling approach based on parameters, local peaks and contour curvature is proposed to overcome the problems of nodes redundancy and high time consumption in the fitting of this kind of scattered data. Numerical experiments are conducted with both simulation and practical data, and the results show that the proposed method is fast, effective and robust. What's more, by analyzing the fitting results acquired form data with different degrees of scatterness it can be demonstrated that the error introduced by resampling is negligible and therefore it is feasible.

  14. 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.

  15. UNMANNED AIRCRAFT SYSTEMS FOR RAPID NEAR SURFACE GEOPHYSICAL MEASUREMENTS

    Directory of Open Access Journals (Sweden)

    J. B. Stoll

    2013-08-01

    Full Text Available This paper looks at some of the unmanned aircraft systems (UAS options and deals with a magnetometer sensor system which might be of interest in conducting rapid near surface geophysical measurements. Few of the traditional airborne geophysical sensors are now capable of being miniaturized to sizes and payload within mini UAS limits (e.g. airborne magnetics, gamma ray spectrometer. Here the deployment of a fluxgate magnetometer mounted on an UAS is presented demonstrating its capability of detecting metallic materials that are buried in the soil. The effectiveness in finding ferrous objects (e.g. UXO, landslides is demonstrated in two case studies.

  16. Measurement of a surface heat flux and temperature

    Science.gov (United States)

    Davis, R. M.; Antoine, G. J.; Diller, T. E.; Wicks, A. L.

    1994-04-01

    The Heat Flux Microsensor is a new sensor which was recently patented by Virginia Tech and is just starting to be marketed by Vatell Corp. The sensor is made using the thin-film microfabrication techniques directly on the material that is to be measured. It consists of several thin-film layers forming a differential thermopile across a thermal resistance layer. The measured heat flux q is proportional to the temperature difference across the resistance layer q= k(sub g)/delta(sub g) x (t(sub 1) - T(sub 2)), where k(sub g) is the thermal conductivity and delta (sub g) is the thickness of the thermal resistance layer. Because the gages are sputter coated directly onto the surface, their total thickness is less than 2 micrometers, which is two orders of magnitude thinner than previous gages. The resulting temperature difference across the thermal resistance layer (delta is less than 1 micrometer) is very small even at high heat fluxes. To generate a measurable signal many thermocouple pairs are put in series to form a differential thermopile. The combination of series thermocouple junctions and thin-film design creates a gage with very attractive characteristics. It is not only physically non-intrusive to the flow, but also causes minimal disruption of the surface temperature. Because it is so thin, the response time is less than 20 microsec. Consequently, the frequency response is flat from 0 to over 50 kHz. Moreover, the signal of the Heat Flux Microsensor is directly proportional to the heat flux. Therefore, it can easily be used in both steady and transient flows, and it measures both the steady and unsteady components of the surface heat flux. A version of the Heat Flux Microsensor has been developed to meet the harsh demands of combustion environments. These gages use platinum and platinum-10 percent rhodium as the thermoelectric materials. The thermal resistance layer is silicon monoxide and a protective coating of Al2O3 is deposited on top of the sensor. The

  17. Temporal and spatial assessments of minimum air temperature using satellite surface temperature measurements in Massachusetts, USA.

    Science.gov (United States)

    Kloog, Itai; Chudnovsky, Alexandra; Koutrakis, Petros; Schwartz, Joel

    2012-08-15

    Although meteorological stations provide accurate air temperature observations, their spatial coverage is limited and thus often insufficient for epidemiological studies. Satellite data expand spatial coverage, enhancing our ability to estimate near surface air temperature (Ta). However, the derivation of Ta from surface temperature (Ts) measured by satellites is far from being straightforward. In this study, we present a novel approach that incorporates land use regression, meteorological variables and spatial smoothing to first calibrate between Ts and Ta on a daily basis and then predict Ta for days when satellite Ts data were not available. We applied mixed regression models with daily random slopes to calibrate Moderate Resolution Imaging Spectroradiometer (MODIS) Ts data with monitored Ta measurements for 2003. Then, we used a generalized additive mixed model with spatial smoothing to estimate Ta in days with missing Ts. Out-of-sample tenfold cross-validation was used to quantify the accuracy of our predictions. Our model performance was excellent for both days with available Ts and days without Ts observations (mean out-of-sample R(2)=0.946 and R(2)=0.941 respectively). Furthermore, based on the high quality predictions we investigated the spatial patterns of Ta within the study domain as they relate to urban vs. non-urban land uses. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. "Rapid Revisit" Measurements of Sea Surface Winds Using CYGNSS

    Science.gov (United States)

    Park, J.; Johnson, J. T.

    2017-12-01

    The Cyclone Global Navigation Satellite System (CYGNSS) is a space-borne GNSS-R (GNSS-Reflectometry) mission that launched December 15, 2016 for ocean surface wind speed measurements. CYGNSS includes 8 small satellites in the same LEO orbit, so that the mission provides wind speed products having unprecedented coverage both in time and space to study multi-temporal behaviors of oceanic winds. The nature of CYGNSS coverage results in some locations on Earth experiencing multiple wind speed measurements within a short period of time (a "clump" of observations in time resulting in a "rapid revisit" series of measurements). Such observations could seemingly provide indications of regions experiencing rapid changes in wind speeds, and therefore be of scientific utility. Temporally "clumped" properties of CYGNSS measurements are investigated using early CYGNSS L1/L2 measurements, and the results show that clump durations and spacing vary with latitude. For example, the duration of a clump can extend as long as a few hours at higher latitudes, with gaps between clumps ranging from 6 to as high as 12 hours depending on latitude. Examples are provided to indicate the potential of changes within a clump to produce a "rapid revisit" product for detecting convective activity. Also, we investigate detector design for identifying convective activities. Results from analyses using recent CYGNSS L2 winds will be provided in the presentation.

  19. Contact angle measurements at the colemanite and realgar surfaces

    Science.gov (United States)

    Koca, Sabiha; Savas, Mehmet

    2004-03-01

    Colemanite is one of the most important boron minerals and covers an important part of Turkey's boron mineral deposits. The friable nature of the colemanite tends to produce a large amount of fines. Flotation appears to be a promising technique to recover colemanite from such fines. During flotation process, selectivity problem arises between colemanite and associated gangue minerals such as realgar. There is a close relationship between floatability of minerals and contact angle. Therefore, surface hydrophobicity of colemanite and realgar minerals were investigated by receding contact angle measurements in the absence and presence of flotation reagents. The water contact angle values at the colemanite surface remained almost unchanged at 32-35° in the solutions of potassium amyl xanthate (KAX), potassium ethyl xanthate (KEX) and petroleum sulphanate (R825) while another petroleum sulphanate (R840), sodium oleate and tallow amine (Armac-T) affected hydrophobicity of colemanite, and the contact angle values increased up to 47°. The contact angle values of 62, 63, 45, 46, 39, and 43° at the realgar surface were obtained in the solutions of KAX, KEX, sodium oleate, R825, R840 and Armac-T, respectively.

  20. 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

  1. Heating power stations - influencing costs by organisational measures; Heizkraftwerke - Kostenbeeinflussung durch organisatorische Massnahmen

    Energy Technology Data Exchange (ETDEWEB)

    Riedlinger, R.A.

    1993-12-31

    The products of district heating and, in the foreseeable future also electrical power, must compete in the market with low prices. Low prices, which still provide a profit, are only possible based on low costs. Low costs are achieved by cost control. The basis for cost control is transparency of costs. Mainly organisational measures were proposed and described. From the individual stages of the organisation, the organisational build-up is obtained, the important feature of which is the allocation of competence to make decisions. (orig./KO) [Deutsch] Die Produkte Fernwaerme und in absehbarer Zeit auch elektrische Energie, muessen sich im Markt mit niedrigen Preisen behaupten. Niedrige Preise, die trotzdem einen Gewinn erbringen sollen, sind nur auf der Basis niedriger Kosten moeglich. Niedrige Kosten erreicht man durch Kostensteuerung, Controlling. Grundlage der Kostensteuerung ist Kostentransparenz. Es wurden im wesentlichen ablauforganisatorische Massnahmen vorgeschlagen und beschrieben. Aus den einzelnen Stationen der Ablauforganisation ergibt sich letztendlich die Aufbauorganisation, deren wesentliches Merkmal die Zuordnung von Entscheidungskompetenz ist. (orig./KO)

  2. Report on acoustic and vibration measurements on 250 MVA transformer at St. Vital Station, Winnipeg, Manitoba

    International Nuclear Information System (INIS)

    Weissman, K.; McLoughlin, M.; Schott, R.; Tennese, G.; Daneryd, A.

    1998-09-01

    Vibroacoustic behaviour of a power transformer was characterized prior to employing active noise control (ANC) to control transformer noise. The effect of changes in temperature and loading conditions on the vibration pattern of the transformer tank received particular attention. The transformer quieting technology has been developed and implemented by QuietPower Systems of New York and Noise Cancellation Technologies Inc., of Maryland. Results of the study will be used to ensure that actuator placement is appropriate for each of the seasons experienced throughout the year, as well as to build boundary element and finite element models of the tank vibration and the associated radiated noise. Boundary element results show that the first four harmonics are the primary contributors to radiated noise. The finite element model used to examine the modal response of the tank structure showed high modal densities, even around the lower order harmonics (120 Hz). This can be interpreted to mean that statistical techniques normally associated with high frequency noise problems may be applicable here because of the high modal density. Results of the completed summer and winter measurements permit an evaluation of the effects of loading conditions, temperature and other environmental factors on transformer noise. Appendix B contains the results of numerical simulations on a 250 MVA transformer. 3 refs., 72 figs., 2 appendices

  3. Lessons learned from early direct measurements at Fukushima Medical University after the Fukushima Nuclear Power Station accident

    Energy Technology Data Exchange (ETDEWEB)

    Miyazaki, Makoto; Ohba, Takashi; Ohtsuru, Akira [Fukushima Medical Univ., Dept. of Radiation Health Management, Fukushima, Fukushima (Japan)

    2012-11-15

    The Fukushima Daiichi Nuclear Power Station (FDNPS) accident resulted in a month-long discharge of radioactive materials into the environment. These radioactive materials were detected at Fukushima Medical University (FMU), which is 57 km northwest of the FDNPS. Significant levels of six nuclides (i.e., {sup 131}I, {sup 132}Te, {sup 132}I, {sup 133}Xe, {sup 134}Cs, and {sup 137}Cs) were detected by a whole body counter (WBC) on March 15, 2011 when the ambient dose rate was suddenly elevated for the first time. This WBC has a dual detector system consisting of two NaI(Tl) detectors and two Ge detectors. We conducted periodical measurements of 32 humans and the background using the WBC. Because the three nuclides {sup 131}I, {sup 134}Cs and {sup 137}Cs were still detected in the background by the WBC a few months after the accident, accurate WBC measurements were difficult. Here we describe the limitations of our measurements conducted in the early stage of the FDNPS accident. (author)

  4. Specific absorption rate and electric field measurements in the near field of six mobile phone base station antennas.

    Science.gov (United States)

    Toivonen, Tommi; Toivo, Tim; Puranen, Lauri; Jokela, Kari

    2009-05-01

    In this article, the exposure to radio frequency electromagnetic fields was studied in close proximity (distances of 10, 100, 300, and 600 mm) to six base station antennas. The specific absorption rate (SAR) in 800 mm x 500 mm x 200 mm box phantom as well as unperturbed electric field (E) in air was measured. The results were used to determine whether the measurement of local maximum of unperturbed electric field can be used as a compliance check for local exposure. Also, the conservativeness of this assessment method compared to the ICNIRP basic restriction was studied. Moreover, the assessment of whole-body exposure was discussed and the distance ranges presented in which the ICNIRP limit for local exposure could be exceeded before the limit for whole-body SAR. These results show that the electric field measurement alone can be used for easy compliance check for the local exposure at all distances and for all antenna types studied. However, in some cases when the local peak value of E was compared directly to the ICNIRP reference level for unperturbed E, the exposure was overestimated only very slightly (by factor 1.1) compared to the basic restriction for localized SAR in a human, and hence these results can not be generalized to all antenna types. Moreover, it was shown that the limit for localized exposure could be exceeded before the limit for the whole-body average SAR, if the distance to the antenna was less than 240 mm. Copyright 2009 Wiley-Liss, Inc.

  5. Preliminary GRS Measurement of Chlorine Distribution on Surface of Mars

    Science.gov (United States)

    Keller, J. M.; Boynton, W. V.; Taylor, G. J.; Hamara, D.; Janes, D. M.; Kerry, K.

    2003-12-01

    Ongoing measurements with the Gamma Ray Spectrometer (GRS) aboard Mars Odyssey provide preliminary detection of chlorine at the surface of Mars. Summing all data since boom deployment and using a forward calculation model, we estimate values for chlorine concentration at 5° resolution. Rebinning this data and smoothing with a 15-degree-radius boxcar filter reveal regions of noticeable chlorine enrichment at scales larger than the original 5° resolution and allow for preliminary comparison with previous Mars datasets. Analyzing chlorine concentrations within 30 degrees of the equator, we find a negative correlation with thermal inertia (R2=0.55) and positive correlation with albedo (R2=0.52), indicating that chlorine is associated with fine, non-rock surface materials. Although possibly a smoothing artifact, the spatial correlation is more noticeable in the region covering Tharsis and Amazonis than around Arabia and Elysium. Additionally, a noticeable region of chlorine enrichment appears west of Tharsis Montes ( ˜0 to 20N, ˜110 to 150W) and chlorine concentration is estimated to vary in the equatorial region by over a factor of two. A simplified two-component model involving chlorine-poor rocks and a homogenous chlorine-rich fine material requires rock abundance to vary from zero to over 50%, a result inconsistent with previous measurements and models. In addition to variations in rock composition and distribution, substantial variations in chlorine content of various types of fine materials including dust, sand, and duricrust appear important in explaining this preliminary observation. Surprisingly, visual comparison of surface units mapped by Christensen and Moore (1992) does not show enrichment in chlorine associated with regions of indurated surfaces, where cementation has been proposed. Rather, Tharsis, a region of active deposition with proposed mantling of 0.1 to 2 meters of recent dust (Christensen 1986), shows the greatest chlorine signal. In light of

  6. Autonomous target recognition using remotely sensed surface vibration measurements

    Science.gov (United States)

    Geurts, James; Ruck, Dennis W.; Rogers, Steven K.; Oxley, Mark E.; Barr, Dallas N.

    1993-09-01

    The remotely measured surface vibration signatures of tactical military ground vehicles are investigated for use in target classification and identification friend or foe (IFF) systems. The use of remote surface vibration sensing by a laser radar reduces the effects of partial occlusion, concealment, and camouflage experienced by automatic target recognition systems using traditional imagery in a tactical battlefield environment. Linear Predictive Coding (LPC) efficiently represents the vibration signatures and nearest neighbor classifiers exploit the LPC feature set using a variety of distortion metrics. Nearest neighbor classifiers achieve an 88 percent classification rate in an eight class problem, representing a classification performance increase of thirty percent from previous efforts. A novel confidence figure of merit is implemented to attain a 100 percent classification rate with less than 60 percent rejection. The high classification rates are achieved on a target set which would pose significant problems to traditional image-based recognition systems. The targets are presented to the sensor in a variety of aspects and engine speeds at a range of 1 kilometer. The classification rates achieved demonstrate the benefits of using remote vibration measurement in a ground IFF system. The signature modeling and classification system can also be used to identify rotary and fixed-wing targets.

  7. Surface contact potential patches and Casimir force measurements

    International Nuclear Information System (INIS)

    Kim, W. J.; Sushkov, A. O.; Lamoreaux, S. K.; Dalvit, D. A. R.

    2010-01-01

    We present calculations of contact potential surface patch effects that simplify previous treatments. It is shown that, because of the linearity of Laplace's equation, the presence of patch potentials does not affect an electrostatic calibration of a two-plate Casimir measurement apparatus. Using models that include long-range variations in the contact potential across the plate surfaces, a number of experimental observations can be reproduced and explained. For these models, numerical calculations show that if a voltage is applied between the plates which minimizes the force, a residual electrostatic force persists, and that the minimizing potential varies with distance. The residual force can be described by a fit to a simple two-parameter function involving the minimizing potential and its variation with distance. We show the origin of this residual force by use of a simple parallel capacitor model. Finally, the implications of a residual force that varies in a manner different from 1/d on the accuracy of previous Casimir measurements is discussed.

  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. Spatial Representativeness of Surface-Measured Variations of Downward Solar Radiation

    Science.gov (United States)

    Schwarz, M.; Folini, D.; Hakuba, M. Z.; Wild, M.

    2017-12-01

    When using time series of ground-based surface solar radiation (SSR) measurements in combination with gridded data, the spatial and temporal representativeness of the point observations must be considered. We use SSR data from surface observations and high-resolution (0.05°) satellite-derived data to infer the spatiotemporal representativeness of observations for monthly and longer time scales in Europe. The correlation analysis shows that the squared correlation coefficients (R2) between SSR times series decrease linearly with increasing distance between the surface observations. For deseasonalized monthly mean time series, R2 ranges from 0.85 for distances up to 25 km between the stations to 0.25 at distances of 500 km. A decorrelation length (i.e., the e-folding distance of R2) on the order of 400 km (with spread of 100-600 km) was found. R2 from correlations between point observations and colocated grid box area means determined from satellite data were found to be 0.80 for a 1° grid. To quantify the error which arises when using a point observation as a surrogate for the area mean SSR of larger surroundings, we calculated a spatial sampling error (SSE) for a 1° grid of 8 (3) W/m2 for monthly (annual) time series. The SSE based on a 1° grid, therefore, is of the same magnitude as the measurement uncertainty. The analysis generally reveals that monthly mean (or longer temporally aggregated) point observations of SSR capture the larger-scale variability well. This finding shows that comparing time series of SSR measurements with gridded data is feasible for those time scales.

  10. 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)

  11. An Analysis of Fundamental Mode Surface Wave Amplitude Measurements

    Science.gov (United States)

    Schardong, L.; Ferreira, A. M.; van Heijst, H. J.; Ritsema, J.

    2014-12-01

    Seismic tomography is a powerful tool to decipher the Earth's interior structure at various scales. Traveltimes of seismic waves are widely used to build velocity models, whereas amplitudes are still only seldomly accounted for. This mainly results from our limited ability to separate the various physical effects responsible for observed amplitude variations, such as focussing/defocussing, scattering and source effects. We present new measurements from 50 global earthquakes of fundamental-mode Rayleigh and Love wave amplitude anomalies measured in the period range 35-275 seconds using two different schemes: (i) a standard time-domain amplitude power ratio technique; and (ii) a mode-branch stripping scheme. For minor-arc data, we observe amplitude anomalies with respect to PREM in the range of 0-4, for which the two measurement techniques show a very good overall agreement. We present here a statistical analysis and comparison of these datasets, as well as comparisons with theoretical calculations for a variety of 3-D Earth models. We assess the geographical coherency of the measurements, and investigate the impact of source, path and receiver effects on surface wave amplitudes, as well as their variations with frequency in a wider range than previously studied.

  12. Characterization of gloss properties of differently treated polymer coating surfaces by surface clarity measurement methodology.

    Science.gov (United States)

    Gruber, Dieter P; Buder-Stroisznigg, Michael; Wallner, Gernot; Strauß, Bernhard; Jandel, Lothar; Lang, Reinhold W

    2012-07-10

    With one measurement configuration, existing gloss measurement methodologies are generally restricted to specific gloss levels. A newly developed image-analytical gloss parameter called "clarity" provides the possibility to describe the perceptual result of a broad range of different gloss levels with one setup. In order to analyze and finally monitor the perceived gloss of products, a fast and flexible method also for the automated inspection is highly demanded. The clarity parameter is very fast to calculate and therefore usable for fast in-line surface inspection. Coated metal specimens were deformed by varying degree and polished afterwards in order to study the clarity parameter regarding the quantification of varying surface gloss types and levels. In order to analyze the correlation with the human gloss perception a study was carried out in which experts were asked to assess gloss properties of a series of surface samples under standardized conditions. The study confirmed clarity to exhibit considerably better correlation to the human perception than alternative gloss parameters.

  13. The NRPI multi-purpose on-line monitoring station for measurement of natural radioactivity in the ambient atmosphere and in the soil

    International Nuclear Information System (INIS)

    Jilek, K.; Slezakova, M.; Fronka, A.; Prokop, T.; Neubauer, L.

    2017-01-01

    During years 2010 12 an automated, on-line and wireless outdoor measurement station of atmospheric radon, gamma dose rate and meteorological parameters was realised at the National Radiation Protection Institute (NRPI) in Prague. At the turn of the year 2013 an expansion of the existing station was completed. Under the project funded by the Czech Technological Agency a new updated station was established, additionally equipped with modules for measurement of atmospheric radon/thoron short-lived decay products, radon in water and soil and radon exhalation rate from soil. After the introduction of the station updated key detection parameters and benefits, its use for atmospheric modelling and monitoring is demonstrated. There are summarised results from the 3-year measurement period in the NRPI outdoor area in Prague and from simultaneous annual measurement performed by another similar station located near uranium mud fields in DIAMO, state enterprise, Straz pod Ralskem. Observed seasonal and diurnal variations of atmospheric radon concentrations and variability of the equilibrium factor, F, are illustrated and compared. (authors)

  14. 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

  15. CDIP Station Data Collection - All Stations

    Data.gov (United States)

    Scripps Institution of Oceanography, UC San Diego — The Coastal Data Information Program's station data collection consists of all publicly-released coastal environment measurements taken over the program's history, a...

  16. Global Precipitation Measurement (GPM) and International Space Station (ISS) Coordination for CubeSat Deployments to Minimize Collision Risk

    Science.gov (United States)

    Pawloski, James H.; Aviles, Jorge; Myers, Ralph; Parris, Joshua; Corley, Bryan; Hehn, Garrett; Pascucci, Joseph

    2016-01-01

    The Global Precipitation Measurement Mission (GPM) is a joint U.S. and Japan mission to observe global precipitation, extending the Tropical Rainfall Measuring Mission (TRMM), which was launched by H-IIA from Tanegashima in Japan on February 28TH, 2014 directly into its 407km operational orbit. The International Space Station (ISS) is an international human research facility operated jointly by Russia and the USA from NASA's Johnson Space Center (JSC) in Houston Texas. Mission priorities lowered the operating altitude of ISS from 415km to 400km in early 2105, effectively placing both vehicles into the same orbital regime. The ISS has begun a program of deployments of cost effective CubeSats from the ISS that allow testing and validation of new technologies. With a major new asset flying at the same effective altitude as the ISS, CubeSat deployments became a serious threat to GPM and therefore a significant indirect threat to the ISS. This paper describes the specific problem of collision threat to GPM and risk to ISS CubeSat deployment and the process that was implemented to keep both missions safe from collision and maximize their project goals.

  17. The importance of accurate glacier albedo for estimates of surface mass balance on Vatnajökull: evaluating the surface energy budget in a regional climate model with automatic weather station observations

    Science.gov (United States)

    Steffensen Schmidt, Louise; Aðalgeirsdóttir, Guðfinna; Guðmundsson, Sverrir; Langen, Peter L.; Pálsson, Finnur; Mottram, Ruth; Gascoin, Simon; Björnsson, Helgi

    2017-07-01

    A simulation of the surface climate of Vatnajökull ice cap, Iceland, carried out with the regional climate model HIRHAM5 for the period 1980-2014, is used to estimate the evolution of the glacier surface mass balance (SMB). This simulation uses a new snow albedo parameterization that allows albedo to exponentially decay with time and is surface temperature dependent. The albedo scheme utilizes a new background map of the ice albedo created from observed MODIS data. The simulation is evaluated against observed daily values of weather parameters from five automatic weather stations (AWSs) from the period 2001-2014, as well as in situ SMB measurements from the period 1995-2014. The model agrees well with observations at the AWS sites, albeit with a general underestimation of the net radiation. This is due to an underestimation of the incoming radiation and a general overestimation of the albedo. The average modelled albedo is overestimated in the ablation zone, which we attribute to an overestimation of the thickness of the snow layer and not taking the surface darkening from dirt and volcanic ash deposition during dust storms and volcanic eruptions into account. A comparison with the specific summer, winter, and net mass balance for the whole of Vatnajökull (1995-2014) shows a good overall fit during the summer, with a small mass balance underestimation of 0.04 m w.e. on average, whereas the winter mass balance is overestimated by on average 0.5 m w.e. due to too large precipitation at the highest areas of the ice cap. A simple correction of the accumulation at the highest points of the glacier reduces this to 0.15 m w.e. Here, we use HIRHAM5 to simulate the evolution of the SMB of Vatnajökull for the period 1981-2014 and show that the model provides a reasonable representation of the SMB for this period. However, a major source of uncertainty in the representation of the SMB is the representation of the albedo, and processes currently not accounted for in RCMs

  18. The importance of accurate glacier albedo for estimates of surface mass balance on Vatnajökull: evaluating the surface energy budget in a regional climate model with automatic weather station observations

    Directory of Open Access Journals (Sweden)

    L. S. Schmidt

    2017-07-01

    Full Text Available A simulation of the surface climate of Vatnajökull ice cap, Iceland, carried out with the regional climate model HIRHAM5 for the period 1980–2014, is used to estimate the evolution of the glacier surface mass balance (SMB. This simulation uses a new snow albedo parameterization that allows albedo to exponentially decay with time and is surface temperature dependent. The albedo scheme utilizes a new background map of the ice albedo created from observed MODIS data. The simulation is evaluated against observed daily values of weather parameters from five automatic weather stations (AWSs from the period 2001–2014, as well as in situ SMB measurements from the period 1995–2014. The model agrees well with observations at the AWS sites, albeit with a general underestimation of the net radiation. This is due to an underestimation of the incoming radiation and a general overestimation of the albedo. The average modelled albedo is overestimated in the ablation zone, which we attribute to an overestimation of the thickness of the snow layer and not taking the surface darkening from dirt and volcanic ash deposition during dust storms and volcanic eruptions into account. A comparison with the specific summer, winter, and net mass balance for the whole of Vatnajökull (1995–2014 shows a good overall fit during the summer, with a small mass balance underestimation of 0.04 m w.e. on average, whereas the winter mass balance is overestimated by on average 0.5 m w.e. due to too large precipitation at the highest areas of the ice cap. A simple correction of the accumulation at the highest points of the glacier reduces this to 0.15 m w.e. Here, we use HIRHAM5 to simulate the evolution of the SMB of Vatnajökull for the period 1981–2014 and show that the model provides a reasonable representation of the SMB for this period. However, a major source of uncertainty in the representation of the SMB is the representation of the albedo, and processes

  19. Surface energy budget and thermal inertia at Gale Crater: Calculations from ground-based measurements.

    Science.gov (United States)

    Martínez, G M; Rennó, N; Fischer, E; Borlina, C S; Hallet, B; de la Torre Juárez, M; Vasavada, A R; Ramos, M; Hamilton, V; Gomez-Elvira, J; Haberle, R M

    2014-08-01

    The analysis of the surface energy budget (SEB) yields insights into soil-atmosphere interactions and local climates, while the analysis of the thermal inertia ( I ) of shallow subsurfaces provides context for evaluating geological features. Mars orbital data have been used to determine thermal inertias at horizontal scales of ∼10 4  m 2 to ∼10 7  m 2 . Here we use measurements of ground temperature and atmospheric variables by Curiosity to calculate thermal inertias at Gale Crater at horizontal scales of ∼10 2  m 2 . We analyze three sols representing distinct environmental conditions and soil properties, sol 82 at Rocknest (RCK), sol 112 at Point Lake (PL), and sol 139 at Yellowknife Bay (YKB). Our results indicate that the largest thermal inertia I  = 452 J m -2  K -1  s -1/2 (SI units used throughout this article) is found at YKB followed by PL with I  = 306 and RCK with I  = 295. These values are consistent with the expected thermal inertias for the types of terrain imaged by Mastcam and with previous satellite estimations at Gale Crater. We also calculate the SEB using data from measurements by Curiosity's Rover Environmental Monitoring Station and dust opacity values derived from measurements by Mastcam. The knowledge of the SEB and thermal inertia has the potential to enhance our understanding of the climate, the geology, and the habitability of Mars.

  20. Measurement of pressure on a surface using bubble acoustic resonances

    International Nuclear Information System (INIS)

    Aldham, Ben; Manasseh, Richard; Liffman, Kurt; Šutalo, Ilija D; Illesinghe, Suhith; Ooi, Andrew

    2010-01-01

    The frequency response of gas bubbles as a function of liquid ambient pressure was measured and compared with theory. A bubble size with equivalent spherical radius of 2.29 mm was used over a frequency range of 1000–1500 Hz. The ultimate aim is to develop an acoustic sensor that can measure static pressure and is sensitive to variations as small as a few kPa. The classical bubble resonance frequency is known to vary with ambient pressure. Experiments were conducted with a driven bubble in a pressurizable tank with a signal processing system designed to extract the resonant peak. Since the background response of the containing tank is significant, particularly near tank-modal resonances, it must be carefully removed from the bubble response signal. A dual-hydrophone method was developed to allow rapid and reliable real-time measurements. The expected pressure dependence was found. In order to obtain a reasonable match with theory, the classical theory was modified by the introduction of a 'mirror bubble' to account for the influence of a nearby surface. (technical design note)

  1. High-sensitivity strain measurements from underground interferometric stations: geodynamic phenomena at Gran Sasso and first records from Canfranc

    OpenAIRE

    Botta, Verdiana

    2013-01-01

    2011 - 2012 Earth's surface and interior continuously deform as a result of geological and geophys- ical processes. To study these phenomena and to understand better the rheological properties of the Earth, measurements of Earth's deformation become of fundamental importance, providing a critical link between Earth's structure and dynamics, also in order to optimize the response to natural hazards and identify potential risk areas. The study of crustal deformation is a compl...

  2. Surface ozone measurements in the southwest of the Iberian Peninsula (Huelva, Spain).

    Science.gov (United States)

    Carnero, Jose A Adame; Bolívar, Juan P; de la Morena, Benito A

    2010-02-01

    Photochemical ozone pollution of the lower troposphere (LT) is a very complex process involving meteorological, topographic emissions and chemical parameters. Ozone is considered the most important air pollutant in rural, suburban and industrial areas of many sites in the world since it strongly affects human health, vegetation and forest ecosystems, and its increase during the last decades has been significant. In addition, ozone is a greenhouse gas that contributes to climate change. For these reasons, it is necessary to carry out investigations that determine the behaviour of ozone at different locations. The aim of this work is to understand the levels and temporal variations of surface ozone in an industrial-urban region of the Southwest Iberian Peninsula. The study is based on ozone hourly data recorded during a 6-year period, 2000 to 2005 at four stations and meteorological data from a coastal station. The stations used were El Arenosillo and Cartaya--both coastal stations, Huelva--an urban site and Valverde--an inland station 50 km away from the coastline. The general characteristics of the ozone series, seasonal and daily ozone cycles as well as number of exceedances of the threshold established in the European Ozone Directive have been calculated and analysed. Analysis of the meteorological data shows that winter-autumn seasons are governed by the movement of synoptic weather systems; however, in the spring-summer seasons, both synoptic and mesoescale conditions exist. Average hourly ozone concentrations range from 78.5 +/- 0.1 microg m(-3) at Valverde to 57.8 +/- 0.2 microg m(-3) at Huelva. Ozone concentrations present a seasonal variability with higher values in summer months, while in wintertime, lower values are recorded. A seasonal daily evolution has also been found with minimum levels around 08:00 UTC, which occurs approximately 1-1.5 h after sunrise, whereas the maximum is reached at about 16:00 UTC. Furthermore, during summer, the maximum value

  3. 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.

  4. Improved boundary layer height measurement using a fuzzy logic method: Diurnal and seasonal variabilities of the convective boundary layer over a tropical station

    Science.gov (United States)

    Allabakash, S.; Yasodha, P.; Bianco, L.; Venkatramana Reddy, S.; Srinivasulu, P.; Lim, S.

    2017-09-01

    This paper presents the efficacy of a "tuned" fuzzy logic method at determining the height of the boundary layer using the measurements from a 1280 MHz lower atmospheric radar wind profiler located in Gadanki (13.5°N, 79°E, 375 mean sea level), India, and discusses the diurnal and seasonal variations of the measured convective boundary layer over this tropical station. The original fuzzy logic (FL) method estimates the height of the atmospheric boundary layer combining the information from the range-corrected signal-to-noise ratio, the Doppler spectral width of the vertical velocity, and the vertical velocity itself, measured by the radar, through a series of thresholds and rules, which did not prove to be optimal for our radar system and geographical location. For this reason the algorithm was tuned to perform better on our data set. Atmospheric boundary layer heights obtained by this tuned FL method, the original FL method, and by a "standard method" (that only uses the information from the range-corrected signal-to-noise ratio) are compared with those obtained from potential temperature profiles measured by collocated Global Positioning System Radio Sonde during years 2011 and 2013. The comparison shows that the tuned FL method is more accurate than the other methods. Maximum convective boundary layer heights are observed between 14:00 and 15:00 local time (LT = UTC + 5:30) for clear-sky days. These daily maxima are found to be lower during winter and postmonsoon seasons and higher during premonsoon and monsoon seasons, due to net surface radiation and convective processes over this region being more intense during premonsoon and monsoon seasons and less intense in winter and postmonsoon seasons.

  5. [Study on pollution evaluation of heavy metal in surface soil of the original site of Qingdao North Station].

    Science.gov (United States)

    Zhu, Lei; Jia, Yong-gang; Pan, Yu-ying

    2013-09-01

    The determination of pollution extent and health risk assessment are the premise of heavy metal contaminated site remediation. The content of Cu, Cr, Pb, Cd, Zn, Ni in Qingdao North Station was detected, and the correlation of the 6 kinds of heavy metal content was analyzed. The pollution extent in excess of background values was characterized by anthropogenic influence multiple, and the pollution of heavy metal in soil was evaluated using geoaccumulation index and a new method which connects geoaccumulation index with Nemero index. Finally, human health risk assessment was carried out with health risk assessment model for heavy metal content. The results showed that Qingdao North Station soil were polluted by heavy metals. Six heavy metal pollution levels were: Cd > Cu > Ni > Pb > Cr > Zn, and Cd had reached the severity pollution level, Cu and Ni followed by, Cr, Pb and Zn were in minor pollution level. The order of coefficient variation in all heavy metals was: Cd > Ni > Cr > Zn > Pb > Cu. Within the study area soil heavy metal distribution was different, but overall discrepancy was small. The order of non-cancer hazards of heavy metals in soil was Cr > Pb > Cu > Ni > Cd > Zn, and the order of carcinogen risks of heavy metals was Ni > Cd. The non-cancer hazard and carcinogen risks values of metals were both lower than that their threshold values. They were not the direct threats to human health.

  6. Interstation phase speed and amplitude measurements of surface waves with nonlinear waveform fitting: application to USArray

    Science.gov (United States)

    Hamada, K.; Yoshizawa, K.

    2015-09-01

    A new method of fully nonlinear waveform fitting to measure interstation phase speeds and amplitude ratios is developed and applied to USArray. The Neighbourhood Algorithm is used as a global optimizer, which efficiently searches for model parameters that fit two observed waveforms on a common great-circle path by modulating the phase and amplitude terms of the fundamental-mode surface waves. We introduce the reliability parameter that represents how well the waveforms at two stations can be fitted in a time-frequency domain, which is used as a data selection criterion. The method is applied to observed waveforms of USArray for seismic events in the period from 2007 to 2010 with moment magnitude greater than 6.0. We collect a large number of phase speed data (about 75 000 for Rayleigh and 20 000 for Love) and amplitude ratio data (about 15 000 for Rayleigh waves) in a period range from 30 to 130 s. The majority of the interstation distances of measured dispersion data is less than 1000 km, which is much shorter than the typical average path-length of the conventional single-station measurements for source-receiver pairs. The phase speed models for Rayleigh and Love waves show good correlations on large scales with the recent tomographic maps derived from different approaches for phase speed mapping; for example, significant slow anomalies in volcanic regions in the western Unites States and fast anomalies in the cratonic region. Local-scale phase speed anomalies corresponding to the major tectonic features in the western United States, such as Snake River Plains, Basin and Range, Colorado Plateau and Rio Grande Rift have also been identified clearly in the phase speed models. The short-path information derived from our interstation measurements helps to increase the achievable horizontal resolution. We have also performed joint inversions for phase speed maps using the measured phase and amplitude ratio data of vertical component Rayleigh waves. These maps exhibit

  7. Fire Stations

    Data.gov (United States)

    Department of Homeland Security — Fire Stations in the United States Any location where fire fighters are stationed or based out of, or where equipment that such personnel use in carrying out their...

  8. Close Range Photogrammetry in Space - Measuring the On-Orbit Clearance between Hardware on the International Space Station

    Science.gov (United States)

    Liddle, Donn

    2017-01-01

    real clearance between the ammonia lines and expected position of the thruster bell using existing on-orbit imagery. Imagery of the area of interest, taken several years earlier from the Space Shuttle during a fly-around of the ISS, was found and used to set a stereo pair. Space Vision System Targets and Handrail bolts measured in the ISS analytical coordinate system (ISSACS) prior to launch, were used to obtain an absolute orientation so all photogrammetric measurement's would be in the ISSACS coordinate system. Coordinates for the design location of the edges of the thruster bell, when the cargo vehicle was fully berthed to the ISS, were displayed in 3-D relative to the as-installed ammonia lines. This immediately revealed a positive clearance, which was later quantified to be a minimum of 10" +/0.5". The analysis was completed over a single weekend by a single analyst. Using updated imagery, acquired from the station's robotic arm, a complete as-installed model of the coolant lines was generated from stereo photography and replaced the design model in the master ISS CAD database.

  9. Analysis of antenna position measurements and weather station network data during the ALMA long baseline campaign of 2015

    Science.gov (United States)

    Hunter, Todd R.; Lucas, Robert; Broguière, Dominique; Fomalont, Ed B.; Dent, William R. F.; Phillips, Neil; Rabanus, David; Vlahakis, Catherine

    2016-07-01

    In a radio interferometer, the geometrical antenna positions are determined from measurements of the observed delay to each antenna from observations across the sky of many point sources whose positions are known to high accuracy. The determination of accurate antenna positions relies on accurate calibration of the dry and wet delay of the atmosphere above each antenna. For the Atacama Large Millimeter/Submillimeter Array (ALMA), with baseline lengths up to 15 kilometers, the geography of the site forces the height above mean sea level of the more distant antenna pads to be significantly lower than the central array. Thus, both the ground level meteorological values and the total water column can be quite different between antennas in the extended configurations. During 2015, a network of six additional weather stations was installed to monitor pressure, temperature, relative humidity and wind velocity, in order to test whether inclusion of these parameters could improve the repeatability of antenna position determinations in these configurations. We present an analysis of the data obtained during the ALMA Long Baseline Campaign of October through November 2015. The repeatability of antenna position measurements typically degrades as a function of antenna distance. Also, the scatter is more than three times worse in the vertical direction than in the local tangent plane, suggesting that a systematic effect is limiting the measurements. So far we have explored correcting the delay model for deviations from hydrostatic equilibrium in the measured air pressure and separating the partial pressure of water from the total pressure using water vapor radiometer (WVR) data. Correcting for these combined effects still does not provide a good match to the residual position errors in the vertical direction. One hypothesis is that the current model of water vapor may be too simple to fully remove the day-to-day variations in the wet delay. We describe possible new avenues of

  10. 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.

  11. A Mobile System for Measuring Water Surface Velocities Using Unmanned Aerial Vehicle and Large-Scale Particle Image Velocimetry

    Science.gov (United States)

    Chen, Y. L.

    2015-12-01

    Measurement technologies for velocity of river flow are divided into intrusive and nonintrusive methods. Intrusive method requires infield operations. The measuring process of intrusive methods are time consuming, and likely to cause damages of operator and instrument. Nonintrusive methods require fewer operators and can reduce instrument damages from directly attaching to the flow. Nonintrusive measurements may use radar or image velocimetry to measure the velocities at the surface of water flow. The image velocimetry, such as large scale particle image velocimetry (LSPIV) accesses not only the point velocity but the flow velocities in an area simultaneously. Flow properties of an area hold the promise of providing spatially information of flow fields. This study attempts to construct a mobile system UAV-LSPIV by using an unmanned aerial vehicle (UAV) with LSPIV to measure flows in fields. The mobile system consists of a six-rotor UAV helicopter, a Sony nex5T camera, a gimbal, an image transfer device, a ground station and a remote control device. The activate gimbal helps maintain the camera lens orthogonal to the water surface and reduce the extent of images being distorted. The image transfer device can monitor the captured image instantly. The operator controls the UAV by remote control device through ground station and can achieve the flying data such as flying height and GPS coordinate of UAV. The mobile system was then applied to field experiments. The deviation of velocities measured by UAV-LSPIV of field experiments and handhold Acoustic Doppler Velocimeter (ADV) is under 8%. The results of the field experiments suggests that the application of UAV-LSPIV can be effectively applied to surface flow studies.

  12. Surface force measurements and simulations of mussel-derived peptide adhesives on wet organic surfaces.

    Science.gov (United States)

    Levine, Zachary A; Rapp, Michael V; Wei, Wei; Mullen, Ryan Gotchy; Wu, Chun; Zerze, Gül H; Mittal, Jeetain; Waite, J Herbert; Israelachvili, Jacob N; Shea, Joan-Emma

    2016-04-19

    Translating sticky biological molecules-such as mussel foot proteins (MFPs)-into synthetic, cost-effective underwater adhesives with adjustable nano- and macroscale characteristics requires an intimate understanding of the glue's molecular interactions. To help facilitate the next generation of aqueous adhesives, we performed a combination of surface forces apparatus (SFA) measurements and replica-exchange molecular dynamics (REMD) simulations on a synthetic, easy to prepare, Dopa-containing peptide (MFP-3s peptide), which adheres to organic surfaces just as effectively as its wild-type protein analog. Experiments and simulations both show significant differences in peptide adsorption on CH3-terminated (hydrophobic) and OH-terminated (hydrophilic) self-assembled monolayers (SAMs), where adsorption is strongest on hydrophobic SAMs because of orientationally specific interactions with Dopa. Additional umbrella-sampling simulations yield free-energy profiles that quantitatively agree with SFA measurements and are used to extract the adhesive properties of individual amino acids within the context of MFP-3s peptide adhesion, revealing a delicate balance between van der Waals, hydrophobic, and electrostatic forces.

  13. Detection of cracks with low vertical offset in clayey formations from galleries by using seismic methods. Tournemire experimental station. First part: problem analysis and measurement sizing

    International Nuclear Information System (INIS)

    Bretaudeau, Francois; Gelis, Celine; Cabrera, Justo; Leparoux, Donatienne; Cote, Philippe

    2012-01-01

    Within the frame of the expertise of the ANDRA file on the project of storage of radioactive wastes in clayey formations, the detection of natural cracks which could locally alter the argillite containment properties is a crucial issue. As some previous studies showed that some cracks exhibiting a low vertical offset could not be detected in clayey formations from the surface, this document reports a study which aimed at assessing the possibility of detection of such a crack by means of seismic methods directly implemented from underground works. It reports a detailed analysis of the seismic imagery problem, the characterization of different areas of the investigated environment, the assessment and validation of various hypotheses by using experimental data obtained in an experimental station and numerical simulations. The potential of each envisaged method (migration, tomography, wave form inversion) is assessed, notably with respect to synthetic seismic data obtained by numerical modelling. Preliminary results are used to size a complete seismic measurement campaign aimed at the characterization of the crack area, and at the assessment of detection limitations of the different methods

  14. Surface characterization of hemodialysis membranes based on streaming potential measurements.

    Science.gov (United States)

    Werner, C; Jacobasch, H J; Reichelt, G

    1995-01-01

    Hemodialysis membranes made from cellulose (CUPROPHAN, HEMOPHAN) and sulfonated polyethersulfone (SPES) were characterized using the streaming potential technique to determine the zeta potential at their interfaces against well-defined aqueous solutions of varied pH and potassium chloride concentrations. Streaming potential measurements enable distinction between different membrane materials. In addition to parameters of the electrochemical double layer at membrane interfaces, thermodynamic characteristics of adsorption of different solved species were evaluated. For that aim a description of double layer formation as suggested by Börner and Jacobasch (in: Electrokinetic Phenomena, p. 231. Institut für Technologie der Polymere, Dresden (1989)) was applied which is based on the generally accepted model of the electrochemical double layer according to Stern (Z. Elektrochemie 30, 508 (1924)) and Grahame (Chem. Rev. 41, 441 (1947)). The membranes investigated show different surface acidic/basic and polar/nonpolar behavior. Furthermore, alterations of membrane interfaces through adsorption processes of components of biologically relevant solutions were shown to be detectable by streaming potential measurements.

  15. A Method for Dimensional and Surface Optical Measurements Uncertainty Assessment on Micro Structured Surfaces Manufactured by Jet-ECM

    DEFF Research Database (Denmark)

    Quagliotti, Danilo; Tosello, Guido; Islam, Aminul

    2015-01-01

    Surface texture and step height measurements of electrochemically machined cavities have been compared among optical and tactile instruments. A procedure is introduced for correcting possible divergences among the instruments and, ultimately, for evaluating the measurement uncertainty according t...

  16. Ground-based FTIR measurements of CO from the Jungfraujoch: characterisation and comparison with in situ surface and MOPITT data

    Directory of Open Access Journals (Sweden)

    B. Barret

    2003-01-01

    Full Text Available CO vertical profiles have been retrieved from solar absorption FTIR spectra recorded at the NDSC station of the Jungfraujoch (46.5º N, 8º E and 3580 m a.s.l. for the period from January 1997 to May 2001. The characterisation of these profiles has been established by an information content analysis and an estimation of the error budgets. A partial validation of the profiles has been performed through comparisons with correlative measurements. The average volume mixing ratios (vmr in the 3 km layer above the station have been compared with coincident surface measurements. The agreement between monthly means from both measurement techniques is very good, with a correlation coefficient of 0.87, and no significant bias observed. The FTIR total columns have also been compared to CO partial columns above 3580 m a.s.l. derived from the MOPITT (Measurement Of Pollution In The Troposphere instrument for the period March 2000 to May 2001. Relative to the FTIR columns, the MOPITT partial columns exhibit a positive bias of 8±8% for daytime and of 4±7% for nighttime measurements.

  17. Leidenfrost drops cooling surfaces: theory and interferometric measurement

    OpenAIRE

    Van Limbeek, Michiel A. J.; Klein Schaarsberg, Martin H.; Sobac, Benjamin; Rednikov, Alexey; Sun, Chao; Colinet, Pierre; Lohse, Detlef

    2017-01-01

    When a liquid drop is placed on a highly superheated surface, it can be levitated by its own vapour. This remarkable phenomenon is referred to as the Leidenfrost effect. The thermally insulating vapour film results in a severe reduction of the heat transfer rate compared to experiments at lower surface temperatures, where the drop is in direct contact with the solid surface. A commonly made assumption is that this solid surface is isothermal, which is at least questionable for materials of lo...

  18. Sorption (Kd) measurements on cinder block and grout in support of dose assessments for Zion Nuclear Station decommissioning

    Energy Technology Data Exchange (ETDEWEB)

    Milian L.; Sullivan T.

    2014-06-24

    The Zion Nuclear Power Station is being decommissioned. ZionSolutions proposes to leave much of the below grade structures in place and to fill them with a backfill to provide structural support. Backfills under consideration include “clean” concrete demolition debris from the above grade parts of the facility, a flowable grout, cinder block construction debris and sand. A previous study (Yim, 2012) examined the sorption behavior of five nuclides (Fe-55, Co-60, Ni-63, Sr-85, and Cs-137) on concrete and local soils. This study, commissioned by ZionSolutions and conducted by the Brookhaven National Laboratory (BNL) examines the sorption behavior on cinder block and grout materials. Specifically, this study measured the distribution coefficient for four radionuclides of concern using site-groundwater and cinder block from the Zion site and a flowable grout. The distributions coefficient is a measure of the amount of the radionuclide that will remain sorbed to the solid material that is present relative to the amount that will remain in solution. A high distribution coefficient indicates most of the radionuclide will remain on the solid material and will not be available for transport by the groundwater. The radionuclides examined in this set of tests were Co-60, Ni-63, Sr-85, and Cs-137. Tests were performed following ASTM C1733-10, Standard Test Methods for Distribution Coefficients of Inorganic Species by the Batch Method. Sr-85 was used in the testing as an analogue for Sr-90 because it behaves similarly with respect to sorption and has a gamma emission that is easier to detect than the beta emission from Sr-90.

  19. A precipitation database of station-based daily and monthly measurements for West Africa: Overview, quality control and harmonization

    Science.gov (United States)

    Bliefernicht, Jan; Waongo, Moussa; Annor, Thompson; Laux, Patrick; Lorenz, Manuel; Salack, Seyni; Kunstmann, Harald

    2017-04-01

    West Africa is a data sparse region. High quality and long-term precipitation data are often not readily available for applications in hydrology, agriculture, meteorology and other needs. To close this gap, we use multiple data sources to develop a precipitation database with long-term daily and monthly time series. This database was compiled from 16 archives including global databases e.g. from the Global Historical Climatology Network (GHCN), databases from research projects (e.g. the AMMA database) and databases of the national meteorological services of some West African countries. The collection consists of more than 2000 precipitation gauges with measurements dating from 1850 to 2015. Due to erroneous measurements (e.g. temporal offsets, unit conversion errors), missing values and inconsistent meta-data, the merging of this precipitation dataset is not straightforward and requires a thorough quality control and harmonization. To this end, we developed geostatistical-based algorithms for quality control of individual databases and harmonization to a joint database. The algorithms are based on a pairwise comparison of the correspondence of precipitation time series in dependence to the distance between stations. They were tested for precipitation time series from gages located in a rectangular domain covering Burkina Faso, Ghana, Benin and Togo. This harmonized and quality controlled precipitation database was recently used for several applications such as the validation of a high resolution regional climate model and the bias correction of precipitation projections provided the Coordinated Regional Climate Downscaling Experiment (CORDEX). In this presentation, we will give an overview of the novel daily and monthly precipitation database and the algorithms used for quality control and harmonization. We will also highlight the quality of global and regional archives (e.g. GHCN, GSOD, AMMA database) in comparison to the precipitation databases provided by the

  20. The Jungfraujoch high-alpine research station (3454 m) as a background clean continental site for the measurement of aerosol parameters

    International Nuclear Information System (INIS)

    Nyeki, S.; Baltensperger, U.; Jost, D.T.; Weingartner, E.; Colbeck, I.

    1997-01-01

    Aerosol physical parameter measurements are reported here for the first full annual set of data from the Jungfraujoch site. Comparison to NOAA background and regional stations indicate that the site may be designated as 'clean continental' during the free tropospheric influenced period 03:00 -09:00. (author) figs., tab., refs

  1. The Jungfraujoch high-alpine research station (3454 m) as a background clean continental site for the measurement of aerosol parameters

    Energy Technology Data Exchange (ETDEWEB)

    Nyeki, S.; Baltensperger, U.; Jost, D.T.; Weingartner, E. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Colbeck, I. [Essex Univ., Colchester (United Kingdom)

    1997-09-01

    Aerosol physical parameter measurements are reported here for the first full annual set of data from the Jungfraujoch site. Comparison to NOAA background and regional stations indicate that the site may be designated as `clean continental` during the free tropospheric influenced period 03:00 -09:00. (author) figs., tab., refs.

  2. Analysis of South Atlantic Anomaly perturbations on Sentinel-3A Ultra Stable Oscillator. Impact on DORIS phase measurement and DORIS station positioning

    Science.gov (United States)

    Jalabert, Eva; Mercier, Flavien

    2018-07-01

    DORIS measurements rely on the precise knowledge of the embedded oscillator which is called the Ultra Stable Oscillator (DORIS USO). The important radiations in the South Atlantic Anomaly (SAA) perturb the USO behavior by causing rapid frequency variations when the satellite is flying through the SAA. These variations are not taken into account in standard DORIS processing, since the USO is modelled as a third degree polynomial over 7-10 days. Therefore, there are systematic measurements errors when the satellite passes through SAA. In standard GNSS processing, the clock is directly estimated at each epoch. On Sentinel-3A, the GPS receiver and the DORIS receiver use the same USO. It is thus possible to estimate the behavior of the USO using GPS measurements. This estimated USO behavior can be used in the DORIS processing, instead of the third degree polynomial, hence allowing an estimation of the orbit sensitivity to these USO anomalies. This study shows two main results. First, the SAA effect on the DORIS USO is observed well using GPS measurements. Second, the USO behavior observed with GPS can be used to mitigate the SAA effect. Indeed, when used in Sentinel-3A processing, the resulting DORIS orbit shows improved phase measurements and station positioning for stations inside the SAA (Arequipa and Cachoeira). The phase measurements residuals are improved by up to 10 cm, and station vertical positioning (i.e. on the estimated Up component in the North-East-Up station frame) is improved by up to a few centimeters. However, the orbit itself is not sensitive to the correction because only two stations (out of almost 60) are SAA-sensitive on Sentinel-3A.

  3. Comparative studies of the ITU-T prediction model for radiofrequency radiation emission and real time measurements at some selected mobile base transceiver stations in Accra, Ghana

    International Nuclear Information System (INIS)

    Obeng, S. O

    2014-07-01

    Recent developments in the electronics industry have led to the widespread use of radiofrequency (RF) devices in various areas including telecommunications. The increasing numbers of mobile base station (BTS) as well as their proximity to residential areas have been accompanied by public health concerns due to the radiation exposure. The main objective of this research was to compare and modify the ITU- T predictive model for radiofrequency radiation emission for BTS with measured data at some selected cell sites in Accra, Ghana. Theoretical and experimental assessment of radiofrequency exposures due to mobile base station antennas have been analysed. The maximum and minimum average power density measured from individual base station in the town was 1. 86µW/m2 and 0.00961µW/m2 respectively. The ITU-T Predictive model power density ranged between 6.40mW/m 2 and 0.344W/m 2 . Results obtained showed a variation between measured power density levels and the ITU-T predictive model. The ITU-T model power density levels decrease with increase in radial distance while real time measurements do not due to fluctuations during measurement. The ITU-T model overestimated the power density levels by a factor l0 5 as compared to real time measurements. The ITU-T model was modified to reduce the level of overestimation. The result showed that radiation intensity varies from one base station to another even at the same distance. Occupational exposure quotient ranged between 5.43E-10 and 1.89E-08 whilst general public exposure quotient ranged between 2.72E-09 and 9.44E-08. From the results, it shows that the RF exposure levels in Accra from these mobile phone base station antennas are below the permitted RF exposure limit to the general public recommended by the International Commission on Non-Ionizing Radiation Protection. (au)

  4. On the intrinsic timescales of temporal variability in measurements of the surface solar radiation

    Science.gov (United States)

    Bengulescu, Marc; Blanc, Philippe; Wald, Lucien

    2018-01-01

    This study is concerned with the intrinsic temporal scales of the variability in the surface solar irradiance (SSI). The data consist of decennial time series of daily means of the SSI obtained from high-quality measurements of the broadband solar radiation impinging on a horizontal plane at ground level, issued from different Baseline Surface Radiation Network (BSRN) ground stations around the world. First, embedded oscillations sorted in terms of increasing timescales of the data are extracted by empirical mode decomposition (EMD). Next, Hilbert spectral analysis is applied to obtain an amplitude-modulation-frequency-modulation (AM-FM) representation of the data. The time-varying nature of the characteristic timescales of variability, along with the variations in the signal intensity, are thus revealed. A novel, adaptive null hypothesis based on the general statistical characteristics of noise is employed in order to discriminate between the different features of the data, those that have a deterministic origin and those being realizations of various stochastic processes. The data have a significant spectral peak corresponding to the yearly variability cycle and feature quasi-stochastic high-frequency variability components, irrespective of the geographical location or of the local climate. Moreover, the amplitude of this latter feature is shown to be modulated by variations in the yearly cycle, which is indicative of nonlinear multiplicative cross-scale couplings. The study has possible implications on the modeling and the forecast of the surface solar radiation, by clearly discriminating the deterministic from the quasi-stochastic character of the data, at different local timescales.

  5. Field Measurements of PCB emissions from Building Surfaces Using a New Portable Emission Test Cell

    DEFF Research Database (Denmark)

    Lyng, Nadja; Haven, Rune; Gunnarsen, Lars Bo

    2016-01-01

    The purpose of the study was to measure PCB-emission rates from indoor surfaces on-site in contaminated buildings using a newly developed portable emission test cell. Emission rates were measured from six different surfaces; three untreated surfaces and three remediated surfaces in a contaminated...

  6. Entrance surface dose measurements in pediatric radiological examinations

    International Nuclear Information System (INIS)

    Ribeiro, L.A.; Yoshimura, E.M.

    2008-01-01

    A survey of pediatric radiological examinations was carried out in a reference pediatric hospital of the city of Sao Paulo, in order to investigate the doses to children undergoing conventional X-ray examinations. The results showed that the majority of pediatric patients are below 4 years, and that about 80% of the examinations correspond to chest projections. Doses to typical radiological examinations were measured in vivo with thermoluminescent dosimeters (LiF: Mg, Ti and LiF: Mg, Cu, P) attached to the skin of the children to determine entrance surface dose (ESD). Also homogeneous phantoms were used to obtain ESD to younger children, because the technique uses a so small kVp that the dosimeters would produce an artifact image in the patient radiograph. Four kinds of pediatric examinations were investigated: three conventional examinations (chest, skull and abdomen) and a fluoroscopic procedure (barium swallow). Relevant information about kVp and mAs values used in the examinations was collected, and we discuss how these parameters can affect the ESD. The ESD values measured in this work are compared to reference levels published by the European Commission for pediatric patients. The results obtained (third-quartile of the ESD distribution) for chest AP examinations in three age groups were: 0.056 mGy (2-4 years old); 0.068 mGy (5-9 years old); 0.069 mGy (10-15 years old). All of them are below the European reference level (0.100 mGy). ESD values measured to the older age group in skull and abdomen AP radiographs (mean values 3.44 and 1.20 mGy, respectively) are above the European reference levels (1.5 mGy to skull and 1.0 mGy to abdomen). ESD values measured in the barium swallow examination reached 10 mGy in skin regions corresponding to thyroid and esophagus. It was noticed during this survey that some technicians use, improperly, X-ray fluoroscopy in conventional examinations to help them in positioning the patient. The results presented here are a

  7. FJ-2207 measuring instrument detection pipe surface a level of pollution method

    International Nuclear Information System (INIS)

    Wang Jiangong

    2010-01-01

    On the pipe surface contamination were detected α level of pollution is a frequently encountered dose-detection work. Because the pipeline surface arc, while the measuring probe for the plane, which for accurate measurement difficult. In this paper, on the FJ-2207-type pipe surface contamination measuring instrument measuring pollution levels in the α method was studied. Introduced the FJ-2207 measuring instrument detection pipe surface α pollution levels. Studied this measuring instrument on the same sources of surface, plane α level of radioactivity measured differences in the results obtained control of the apparatus when the direct measurement of the surface correction factor, and gives 32-216 specifications commonly used pipe direct measurement of the amendment factor. Convenient method, test results are reliable for the accurate measurement of pipe pollution levels in the surface of α as a reference and learning. (authors)

  8. Effects of drop size and measuring condition on static contact angle measurement on a superhydrophobic surface with goniometric technique

    International Nuclear Information System (INIS)

    Seo, Kwangseok; Kim, Minyoung; Kim, Do Hyun; Ahn, Jeong Keun

    2015-01-01

    It is not a simple task to measure a contact angle of a water drop on a superhydrophobic surface with sessile drop method, because a roll-off angle is very low. Usually contact angle of a water drop on a superhydrophobic surface is measured by fixing a drop with intentional defects on the surface or a needle. We examined the effects of drop size and measuring condition such as the use of a needle or defects on the static contact angle measurement on superhydrophobic surface. Results showed that the contact angles on a superhydrophobic surface remain almost constant within intrinsic measurement errors unless there is a wetting transition during the measurement. We expect that this study will provide a deeper understanding on the nature of the contact angle and convenient measurement of the contact angle on the superhydrophobic surface.

  9. Measurement and Analysis of Radio-frequency Radiation Exposure Level from Different Mobile Base Transceiver Stations in Ajaokuta and Environs, Nigeria

    OpenAIRE

    Ushie, P. O.; Nwankwo, Victor U. J.; Bolaji, Ayinmode; Osahun, O. D.

    2013-01-01

    We present the result of a preliminary assessment of radio-frequency radiation exposure from selected mobile base stations in Ajaokuta environs. The Power density of RF radiation within a radial distance of 125m was measured. Although values fluctuated due to the influence of other factors, including wave interference from other electromagnetic sources around reference base stations, we show from analysis that radiation exposure level is below the standard limit (4.5W/sqm for 900MHz and 9W/sq...

  10. Promoting the potential of flux-measuring stations in urban parks: An innovative case study in Naples, Italy

    Czech Academy of Sciences Publication Activity Database

    Guidolotti, G.; Calfapietra, Carlo; Pallozzi, E.; De Simoni, G.; Esposito, R.; Mattioni, M.; Nicolini, G.; Matteucci, G.; Brugnoli, E.

    2017-01-01

    Roč. 233, feb (2017), s. 153-162 ISSN 0168-1923 R&D Projects: GA MŠk(CZ) LO1415; GA MŠk(CZ) LD13031 Institutional support: RVO:86652079 Keywords : eddy covariance measurements * net ecosystem exchange * carbon-dioxide fluxes * ozone deposition * air-quality * mediterranean forest * surface fluxes * climate-change * quercus-ilex * water-vapor * Urban forest * Eddy covariance * Greenhouse gases * bvoc * Air pollutants Subject RIV: EH - Ecology, Behaviour OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 3.887, year: 2016

  11. Surface temperature measurements on superconducting cavities in superfluid helium

    International Nuclear Information System (INIS)

    Fouaidy, T.; Junquera, T.; Caruette, A.

    1991-01-01

    Two thermometry systems have been developed: a scanning thermometer system routinely used for the 1.5 GHz monocell cavity studies and a fixed thermometer array used to investigate spatial surface resistance distribution on various SC removable endplates of a cylindrical TE011mode cavity. Thermometers used in these systems are thermally insulated from the surrounding HeII bath by an epoxy housing ('epoxy'thermometers). Accurate calibration of the fixed thermometers was conducted by using different test cells and the experimental results were compared to model calculations performed with a finite element computational code. Measured thermometer efficiency and linearity are in good agreement with numerical results. Some typical temperature maps of different Nb samples obtained with the TE011 array (40 epoxy thermometers) are discussed. On the basis of numerical modelling results, a new type of thermometer with an improved efficiency has been designed. The thermal insulation against Helium II has been drastically improved by placing the sensitive part of the thermometer in a small vacuum jacket ('vacuum' thermometers). Two main goals have been reached with the first prototypes: improved efficiency by a factor of 2.5 - 3, and a bath temperature dependence of the thermal response in good agreement with the expected Kapitza conductance behaviour. Fitting experimental results with numerical modelling data, allow us to estimate the Kapitza conductance. The obtained values are in good agreement with the previous results reported by several authors using a different measurement method. The 'vacuum' thermometers are currently used on the TE011 mode cavity with Nb and NbTiN plates and the first results are presented

  12. UAV BASED BRDF-MEASUREMENTS OF AGRICULTURAL SURFACES WITH PFIFFIKUS

    Directory of Open Access Journals (Sweden)

    G. J. Grenzdörffer

    2012-09-01

    Full Text Available BRDF is a common problem in remote sensing and also in oblique photogrammetry. Common approaches of BRDF-measurement with a field goniometer are costly and rather cumbersome. UAVs may offer an interesting alternative by using a special flight pattern of oblique and converging images. The main part of this paper is the description of a photogrammetric workflow in order to determine the anisotropic reflection properties of a given surface. Due to the relatively low flying heights standard procedures from close range photogrammetry were adopted for outdoor usage. The photogrammetric processing delivered automatic and highly accurate orientation information with the aid of coded targets. The interior orientation of the consumer grade camera is more or less stable. The radiometrically corrected oblique images are converted into ortho photos. The azimuth and elevation angle of every point may then be computed. The calculated anisotropy of a winter wheat plot is shown. A system four diagonally-looking cameras (Four Vision and an additional nadir looking camera is under development. The multi camera system especially designed for a Micro- UAV with a payload of min 1 kg. The system is composed of five industrial digital frame cameras (1.3 Mpix CCD-chips, 15 fp/s with fixed lenses. Also special problems with the construction of a light weight housing of the multi camera solution are covered in the paper.

  13. Variations of surface ozone at Ieodo Ocean Research Station in the East China Sea and the influence of Asian outflows

    Science.gov (United States)

    Han, J.; Shin, B.; Lee, M.; Hwang, G.; Kim, J.; Shim, J.; Lee, G.; Shim, C.

    2015-11-01

    Ieodo Ocean Research Station (IORS), a research tower (~ 40 m a.s.l.) for atmospheric and oceanographic observations, is located in the East China Sea (32.07° N, 125.10° E). The IORS is almost equidistant from South Korea, China, and Japan and, therefore, it is an ideal place to observe Asian outflows without local emission effects. The seasonal variation of ozone was distinct, with a minimum in August (37 ppbv) and two peaks in April and October (62 ppbv), and was largely affected by the seasonal wind pattern over east Asia. At IORS, six types of air masses were distinguished with different levels of O3 concentrations by the cluster analysis of backward trajectories. Marine air masses from the Pacific Ocean represent a relatively clean background air with a lowest ozone level of 32 ppbv, which was most frequently observed in summer (July-August). In spring (March-April) and winter (December-February), the influence of Chinese outflows was dominant with higher ozone concentrations of 62 and 49 ppbv, respectively. This study confirms that the influence of Chinese outflows was the main factor determining O3 levels at IORS and its extent was dependent on meteorological state, particularly at a long-term scale.

  14. Preliminary comparative assessment of PM10 hourly measurement results from new monitoring stations type using stochastic and exploratory methodology and models

    Science.gov (United States)

    Czechowski, Piotr Oskar; Owczarek, Tomasz; Badyda, Artur; Majewski, Grzegorz; Rogulski, Mariusz; Ogrodnik, Paweł

    2018-01-01

    The paper presents selected preliminary stage key issues proposed extended equivalence measurement results assessment for new portable devices - the comparability PM10 concentration results hourly series with reference station measurement results with statistical methods. In article presented new portable meters technical aspects. The emphasis was placed on the comparability the results using the stochastic and exploratory methods methodology concept. The concept is based on notice that results series simple comparability in the time domain is insufficient. The comparison of regularity should be done in three complementary fields of statistical modeling: time, frequency and space. The proposal is based on model's results of five annual series measurement results new mobile devices and WIOS (Provincial Environmental Protection Inspectorate) reference station located in Nowy Sacz city. The obtained results indicate both the comparison methodology completeness and the high correspondence obtained new measurements results devices with reference.

  15. Exploiting different active silicon detectors in the International Space Station: ALTEA and DOSTEL galactic cosmic radiation (GCR) measurements

    Science.gov (United States)

    Narici, Livo; Berger, Thomas; Burmeister, Sönke; Di Fino, Luca; Rizzo, Alessandro; Matthiä, Daniel; Reitz, Günther

    2017-08-01

    The solar system exploration by humans requires to successfully deal with the radiation exposition issue. The scientific aspect of this issue is twofold: knowing the radiation environment the astronauts are going to face and linking radiation exposure to health risks. Here we focus on the first issue. It is generally agreed that the final tool to describe the radiation environment in a space habitat will be a model featuring the needed amount of details to perform a meaningful risk assessment. The model should also take into account the shield changes due to the movement of materials inside the habitat, which in turn produce changes in the radiation environment. This model will have to undergo a final validation with a radiation field of similar complexity. The International Space Station (ISS) is a space habitat that features a radiation environment inside which is similar to what will be found in habitats in deep space, if we use measurements acquired only during high latitude passages (where the effects of the Earth magnetic field are reduced). Active detectors, providing time information, that can easily select data from different orbital sections, are the ones best fulfilling the requirements for these kinds of measurements. The exploitation of the radiation measurements performed in the ISS by all the available instruments is therefore mandatory to provide the largest possible database to the scientific community, to be merged with detailed Computer Aided Design (CAD) models, in the quest for a full model validation. While some efforts in comparing results from multiple active detectors have been attempted, a thorough study of a procedure to merge data in a single data matrix in order to provide the best validation set for radiation environment models has never been attempted. The aim of this paper is to provide such a procedure, to apply it to two of the most performing active detector systems in the ISS: the Anomalous Long Term Effects in Astronauts (ALTEA

  16. Temporal distribution and potential sources of atmospheric mercury measured at a high-elevation background station in Taiwan

    Science.gov (United States)

    Sheu, Guey-Rong; Lin, Neng-Huei; Wang, Jia-Lin; Lee, Chung-Te; Ou Yang, Chang-Feng; Wang, Sheng-Hsiang

    2010-07-01

    Measurements of gaseous elemental mercury (GEM), reactive gaseous mercury (RGM), and particulate mercury (PHg) have been conducted at Lulin Atmospheric Background Station (LABS) in Taiwan since April 2006. This was the first long-term free tropospheric atmospheric Hg monitoring program in the downwind region of East Asia, which is a major Hg emission source region. Between April 13, 2006 and December 31, 2007, the mean concentrations of GEM, RGM, and PHg were 1.73 ng m -3, 12.1 pg m -3, and 2.3 pg m -3, respectively. A diurnal pattern was observed for GEM with afternoon peaks and nighttime lows, whereas the diurnal pattern of RGM was opposite to that of GEM. Spikes of RGM were frequently observed between midnight and early morning with concurrent decreases in GEM and relative humidity and increases in O 3, suggesting the oxidation of GEM and formation of RGM in free troposphere (FT). Upslope movement of boundary layer (BL) air in daytime and subsidence of FT air at night resulted in these diurnal patterns. Considering only the nighttime data, which were more representative of FT air, the composite monthly mean GEM concentrations ranged between 1.06 and 2.06 ng m -3. Seasonal variation in nighttime GEM was evident, with lower concentrations usually occurring in summer when clean marine air masses prevailed. Between fall and spring, air masses passed the East Asian continent prior to reaching LABS, contributing to the elevated GEM concentrations. Analysis of GEM/CO correlation tends to support the argument. Good GEM/CO correlations were observed in fall, winter, and spring, suggesting influence of anthropogenic emission sources. Our results demonstrate the significance of East Asian Hg emissions, including both anthropogenic and biomass burning emissions, and their long-range transport in the FT. Because of the pronounced seasonal monsoon activity and the seasonal variation in regional wind field, export of the Asian Hg emissions to Taiwan occurs mainly during fall

  17. On the measurement of the surface energy budget over a land ...

    Indian Academy of Sciences (India)

    The measurement of surface energy balance over a land surface in an open area in Bangalore is reported. Measurements of all variables needed to calculate the surface energy balance on time scales longer than a week are made. Components of radiative fluxes are measured while sensible and latent heat fluxes are ...

  18. Meteorological Automatic Weather Station (MAWS) Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Holdridge, Donna J [Argonne National Lab. (ANL), Argonne, IL (United States); Kyrouac, Jenni A [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-08-01

    The Meteorological Automatic Weather Station (MAWS) is a surface meteorological station, manufactured by Vaisala, Inc., dedicated to the balloon-borne sounding system (BBSS), providing surface measurements of the thermodynamic state of the atmosphere and the wind speed and direction for each radiosonde profile. These data are automatically provided to the BBSS during the launch procedure and included in the radiosonde profile as the surface measurements of record for the sounding. The MAWS core set of measurements is: Barometric Pressure (hPa), Temperature (°C), Relative Humidity (%), Arithmetic-Averaged Wind Speed (m/s), and Vector-Averaged Wind Direction (deg). The sensors that collect the core variables are mounted at the standard heights defined for each variable.

  19. Amtrak Stations

    Data.gov (United States)

    Department of Homeland Security — Updated database of the Federal Railroad Administration's (FRA) Amtrak Station database. This database is a geographic data set containing Amtrak intercity railroad...

  20. Net Surface Shortwave Radiation from GOES Imagery—Product Evaluation Using Ground-Based Measurements from SURFRAD

    Directory of Open Access Journals (Sweden)

    Anand K. Inamdar

    2015-08-01

    Full Text Available The Earth’s surface net radiation controls the energy and water exchanges between the Earth’s surface and the atmosphere, and can be derived from satellite observations. The ability to monitor the net surface radiation over large areas at high spatial and temporal resolution is essential for many applications, such as weather forecasting, short-term climate prediction or water resources management. The objective of this paper is to derive the net surface radiation in the shortwave domain at high temporal (half-hourly and spatial resolution (~1 km using visible imagery from Geostationary Operational Environmental Satellite (GOES. The retrieval algorithm represents an adaptation to GOES data of a standard algorithm initially developed for the NASA-operated Clouds and Earth’s Radiant Energy System (CERES scanner. The methodology relies on: (1 the estimation of top of atmosphere shortwave radiation from GOES spectral measurements; and (2 the calculation of net surface shortwave (SW radiation accounting for atmospheric effects. Comparison of GOES-retrieved net surface shortwave radiation with ground-measurements at the National Oceanic and Atmospheric Administration’s (NOAA Surface Radiation (SURFRAD stations yields very good agreement with average bias lower than 5 W·m−2 and root mean square difference around 70 W·m−2. The algorithm performance is usually higher over areas characterized by low spatial variability in term of land cover type and surface biophysical properties. The technique does not involve retrieval and assessment of cloud properties and can be easily adapted to other meteorological satellites around the globe.

  1. MEASURING PROTOPLANETARY DISK GAS SURFACE DENSITY PROFILES WITH ALMA

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Jonathan P.; McPartland, Conor, E-mail: jpw@ifa.hawaii.edu [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States)

    2016-10-10

    The gas and dust are spatially segregated in protoplanetary disks due to the vertical settling and radial drift of large grains. A fuller accounting of the mass content and distribution in disks therefore requires spectral line observations. We extend the modeling approach presented in Williams and Best to show that gas surface density profiles can be measured from high fidelity {sup 13}CO integrated intensity images. We demonstrate the methodology by fitting ALMA observations of the HD 163296 disk to determine a gas mass, M {sub gas} = 0.048 M {sub ⊙}, and accretion disk characteristic size R {sub c} = 213 au and gradient γ = 0.39. The same parameters match the C{sup 18}O 2–1 image and indicate an abundance ratio [{sup 12}CO]/[C{sup 18}O] of 700 independent of radius. To test how well this methodology can be applied to future line surveys of smaller, lower mass T Tauri disks, we create a large {sup 13}CO 2–1 image library and fit simulated data. For disks with gas masses 3–10 M {sub Jup} at 150 pc, ALMA observations with a resolution of 0.″2–0.″3 and integration times of ∼20 minutes allow reliable estimates of R {sub c} to within about 10 au and γ to within about 0.2. Economic gas imaging surveys are therefore feasible and offer the opportunity to open up a new dimension for studying disk structure and its evolution toward planet formation.

  2. Developing occupational chronologies for surface archaeological deposits from heat retainer hearths on Pine Point and Langwell stations, Far Western New South Wales, Australia

    International Nuclear Information System (INIS)

    Shiner, J.

    2003-01-01

    The archaeological record of arid Australia is dominated by deflated distributions of stone artefacts and heat retainer hearths covering many thousands of square metres. These deposits have often been over-looked by archaeologists in preference for stratified deposits, which are regarded as more appropriate for investigating temporal issues. In recent years this situation had slowly begun to change with the large-scale dating of heat retainer hearths from surface contexts. The work of of Fanning and Holdaway (2001) and Holdaway et al. (2002) in Far Western New South Wales has demonstrated that through the dating of large numbers of hearths it is possible to develop occupational chronologies for surface deposits. At a wider landscape scale these chronologies reflect the timing and tempo of the occupation of different places. A major component of my doctoral fieldwork on Pine Point and Langwell stations, 50 km south of Broken Hill in Western New South Wales, aimed to establish occupational chronologies from hearths for surface archaeological distributions. This paper reports on radiocarbon results from this investigation. (author). 6 refs., 2 figs., 1 tab

  3. Proposal on the measurements of d-p elastic scattering analyzing powers at 0.3-2.0 GeV at internal target station of the Nuclotron

    International Nuclear Information System (INIS)

    Uesaka, T.; Ladygin, V.P.; Azhgirej, L.S.

    2005-01-01

    A new high-energy beam polarimeter is proposed for the Nuclotron using Internal Target Station. This polarimeter based on the measurement of the asymmetry for the d-p elastic scattering will allow one to measure both vector and tensor components of the deuteron beam polarization simultaneously. For that purpose the measurement of analyzing powers for the d-p elastic scattering at energies T d = 0.88-2 GeV is proposed. The precise measurements of the deuteron analyzing powers over energy range T d 300-2000 MeV can give an irreplaceable clue on the study of spin-dependence of three-nucleon forces

  4. Examination of Surface Residuals Obtained During Re-Lubrication of the International Space Station (ISS) Solar Alpha Rotary Joint (SARJ)

    Science.gov (United States)

    Martinez, J. E.; Golden, J. L.

    2012-01-01

    The starboard SARJ mechanism on the ISS suffered a premature lubrication failure, resulting in widespread loss of the nitride case layer on its 10.3 meter circumference, 15-5PH steel race ring [1, 2]. To restore functionality, vacuum-stable grease was applied on-orbit, first to the port SARJ mechanism to save it from the damage suffered by the starboard mechanism. After 3 years of greased operation, telemetry indicated that the port mechanism required relubrication, so part of that process included sampling each of the three race ring surfaces to evaluate any wear debris recovered and the state of the originally applied grease. Extensive microscopic examination was conducted, which directed subsequent microanalysis of particulate. Since the SARJ mechanism operates in the vacuum of space, a sampling method and tool had to be developed for use by astronauts while working in the extravehicular mobility unit (EMU). The sampling tool developed was a cotton terry-cloth mitt for the EMU glove, with samples taken by swiping each of the three port SARJ race-ring surfaces. The sample mitts for each surface were folded inward after sampling to preserve sample integrity, for return and ground analysis. The sample mitt for what is termed the outer canted surface of the SARJ race-ring is shown in Figure 1. Figure 1 also demonstrates how increasing levels of magnification were used to survey the contamination removed in sampling, specifically looking for signs of wear debris or other features which could be further evaluated using Scanning Electron Microscopy (SEM) methods. The most surprising overall result at this point in the analysis was the relatively small amounts of grease recovered during sampling. It is clear that the mechanism was not operating with surplus lubricant. Obviously, evidence of molybdenum disulfide (MoS2), a major component in the grease applied, was prevalent in the analysis conducted. But a small amount of mechanism wear debris was observed. Figure 2

  5. Measuring the role of seagrasses in regulating sediment surface elevation

    KAUST Repository

    Potouroglou, Maria; Bull, James C.; Krauss, Ken W.; Kennedy, Hilary A.; Fusi, Marco; Daffonchio, Daniele; Mangora, Mwita M.; Githaiga, Michael N.; Diele, Karen; Huxham, Mark

    2017-01-01

    in varying hydrogeomorphological conditions over long periods. In contrast, similar evidence for seagrasses is sparse; the present study is a contribution towards filling this gap. Surface elevation change pins were deployed in four locations, Scotland, Kenya

  6. Surface pressure retrieval from SCIAMACHY measurements in the O2 A Band: validation of the measurements and sensitivity on aerosols

    Directory of Open Access Journals (Sweden)

    B. van Diedenhoven

    2005-01-01

    Full Text Available We perform surface pressure retrievals from cloud-free Oxygen A band measurements of SCIAMACHY. These retrievals can be well validated because surface pressure is a quantity that is, in general, accurately known from meteorological models. Therefore, surface pressure retrievals and their validation provide important insight into the quality of the instrument calibration. Furthermore, they can provide insight into retrievals which are affected by similar radiation transport processes, for example the retrieval of total columns of H2O, CO, CO2 and CH4. In our retrieval aerosols are neglected. Using synthetic measurements, it is shown that for low to moderate surface albedos this leads to an underestimation of the retrieved surface pressures. For high surface albedos this generally leads to an overestimation of the retrieved surface pressures. The surface pressures retrieved from the SCIAMACHY measurements indeed show this dependence on surface albedo, when compared to the corresponding pressures from a meteorological database. However, an offset of about 20 hPa was found, which can not be caused by neglecting aerosols in the retrieval. The same offset was found when comparing the retrieved surface pressures to those retrieved from co-located GOME Oxygen A band measurements. This implies a calibration error in the SCIAMACHY measurements. By adding an offset of 0.86% of the continuum reflectance at 756 nm to the SCIAMACHY reflectance measurements, this systematic bias vanishes.

  7. Measuring the surface inhomogeneity of metals on accreting white dwarfs

    International Nuclear Information System (INIS)

    Montgomery, M H; Hippel, T von; Thompson, S E

    2009-01-01

    Due to the short settling times of metals in DA white dwarf atmospheres, any white dwarfs with photospheric metals must be actively accreting. It is therefore natural to expect that the metals may not be deposited uniformly on the surface of the star. We present calculations showing how the temperature variations associated with white dwarf pulsations lead to an observable diagnostic of the surface metal distribution, and we show what constraints current data sets are able to provide.

  8. Electrostatic pickup station

    CERN Multimedia

    CERN PhotoLab

    1982-01-01

    Electrostatic pickup station, with 4 interleaved electrodes, to measure beam position in the horizontal and vertical plane. This type is used in the transfer lines leaving the PS (TT2, TT70, TTL2). See also 7904075.

  9. FEMA DFIRM Station Start

    Data.gov (United States)

    Minnesota Department of Natural Resources — This table contains information about station starting locations. These locations indicate the reference point that was used as the origin for distance measurements...

  10. Structural dependence of the 5d-metal surface energies as deduced from surface core-level shift measurements

    International Nuclear Information System (INIS)

    Mrartensson, N.; Saalfeld, H.B.; Kuhlenbeck, H.; Neumann, M.

    1989-01-01

    Surface core-level shift measurements performed at the BESSY storage ring yield -0.41(2) eV for Os(0001) and 0.00(10) eV for Re(0001). An analysis of the surface shifts in the 5d transition series shows that the surface energy as a function of Z has a maximum at lower Z for the bcc phase than for the fcc-hcp phases, at W and between Re and Os, respectively

  11. Depletion region surface effects in electron beam induced current measurements

    Energy Technology Data Exchange (ETDEWEB)

    Haney, Paul M.; Zhitenev, Nikolai B. [Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Yoon, Heayoung P. [Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Gaury, Benoit [Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Maryland NanoCenter, University of Maryland, College Park, Maryland 20742 (United States)

    2016-09-07

    Electron beam induced current (EBIC) is a powerful characterization technique which offers the high spatial resolution needed to study polycrystalline solar cells. Current models of EBIC assume that excitations in the p-n junction depletion region result in perfect charge collection efficiency. However, we find that in CdTe and Si samples prepared by focused ion beam (FIB) milling, there is a reduced and nonuniform EBIC lineshape for excitations in the depletion region. Motivated by this, we present a model of the EBIC response for excitations in the depletion region which includes the effects of surface recombination from both charge-neutral and charged surfaces. For neutral surfaces, we present a simple analytical formula which describes the numerical data well, while the charged surface response depends qualitatively on the location of the surface Fermi level relative to the bulk Fermi level. We find that the experimental data on FIB-prepared Si solar cells are most consistent with a charged surface and discuss the implications for EBIC experiments on polycrystalline materials.

  12. Measuring the surface-heating of medical ultrasonic probes

    International Nuclear Information System (INIS)

    Kollmann, Chr; Vacariu, G; Fialka-Moser, V; Bergmann, H

    2004-01-01

    Due to converting losses the probe's surface itself is heated up, especially when emitting into air. Possible temperature increases in an ensemble of 15 different diagnostic and therapeutic ultrasound probes from 7 manufacturers in the frequency range between 0.05-7.5 MHz have been examined. Surface temperatures were detected by means of a calibrated IR-thermographic camera using a scheme of various power and pulse settings, as well as different imaging modalitites as used in clinical routine. Depending on the setup and the output power, the absolute surface temperatures of some of the probes emitting in air can be beyond 43 deg. C within 5-7 min.; a maximum surface temperature of 84 deg. C has been detected. Continuous mode or high pulse repetition frequencies on the therapeutic system side, small focused Doppler modes on the diagnostic system side combined with increased emitted acoustic intensities result in high surface temperatures. Within a worst case scenario a potential risk of negative skin changes (heat damage) or non-optimal therapeutic effects seems to be possible if a therapeutic system is used very often and if its emission continues unintentionally. In general the user should be aware that low emission intensities of e.g. 50 mW cm -2 could already produce hot surfaces

  13. A probability measure for random surfaces of arbitrary genus and bosonic strings in 4 dimensions

    International Nuclear Information System (INIS)

    Albeverio, S.; Hoeegh-Krohn, R.; Paycha, S.; Scarlatti, S.

    1989-01-01

    We define a probability measure describing random surfaces in R D , 3≤D≤13, parametrized by compact Riemann surfaces of arbitrary genus. The measure involves the path space measure for scalar fields with exponential interaction in 2 space time dimensions. We show that it gives a mathematical realization of Polyakov's heuristic measure for bosonic strings. (orig.)

  14. Measuring the role of seagrasses in regulating sediment surface elevation

    KAUST Repository

    Potouroglou, Maria

    2017-09-13

    Seagrass meadows provide numerous ecosystem services and their rapid global loss may reduce human welfare as well as ecological integrity. In common with the other \\'blue carbon\\' habitats (mangroves and tidal marshes) seagrasses are thought to provide coastal defence and encourage sediment stabilisation and surface elevation. A sophisticated understanding of sediment elevation dynamics in mangroves and tidal marshes has been gained by monitoring a wide range of different sites, located in varying hydrogeomorphological conditions over long periods. In contrast, similar evidence for seagrasses is sparse; the present study is a contribution towards filling this gap. Surface elevation change pins were deployed in four locations, Scotland, Kenya, Tanzania and Saudi Arabia, in both seagrass and unvegetated control plots in the low intertidal and shallow subtidal zone. The presence of seagrass had a highly significant, positive impact on surface elevation at all sites. Combined data from the current work and the literature show an average difference of 31 mm per year in elevation rates between vegetated and unvegetated areas, which emphasizes the important contribution of seagrass in facilitating sediment surface elevation and reducing erosion. This paper presents the first multi-site study for sediment surface elevation in seagrasses in different settings and species.

  15. Measuring the role of seagrasses in regulating sediment surface elevation

    Science.gov (United States)

    Potouroglou, Maria; Bull, James C.; Krauss, Ken W.; Kennedy, Hilary A.; Fusi, Marco; Daffonchio, Daniele; Mangora, Mwita M.; Githaiga, Michael N.; Diele, Karen; Huxham, Mark

    2017-01-01

    Seagrass meadows provide numerous ecosystem services and their rapid global loss may reduce human welfare as well as ecological integrity. In common with the other ‘blue carbon’ habitats (mangroves and tidal marshes) seagrasses are thought to provide coastal defence and encourage sediment stabilisation and surface elevation. A sophisticated understanding of sediment elevation dynamics in mangroves and tidal marshes has been gained by monitoring a wide range of different sites, located in varying hydrogeomorphological conditions over long periods. In contrast, similar evidence for seagrasses is sparse; the present study is a contribution towards filling this gap. Surface elevation change pins were deployed in four locations, Scotland, Kenya, Tanzania and Saudi Arabia, in both seagrass and unvegetated control plots in the low intertidal and shallow subtidal zone. The presence of seagrass had a highly significant, positive impact on surface elevation at all sites. Combined data from the current work and the literature show an average difference of 31 mm per year in elevation rates between vegetated and unvegetated areas, which emphasizes the important contribution of seagrass in facilitating sediment surface elevation and reducing erosion. This paper presents the first multi-site study for sediment surface elevation in seagrasses in different settings and species.

  16. An AFM-based pit-measuring method for indirect measurements of cell-surface membrane vesicles

    International Nuclear Information System (INIS)

    Zhang, Xiaojun; Chen, Yuan; Chen, Yong

    2014-01-01

    Highlights: • Air drying induced the transformation of cell-surface membrane vesicles into pits. • An AFM-based pit-measuring method was developed to measure cell-surface vesicles. • Our method detected at least two populations of cell-surface membrane vesicles. - Abstract: Circulating membrane vesicles, which are shed from many cell types, have multiple functions and have been correlated with many diseases. Although circulating membrane vesicles have been extensively characterized, the status of cell-surface membrane vesicles prior to their release is less understood due to the lack of effective measurement methods. Recently, as a powerful, micro- or nano-scale imaging tool, atomic force microscopy (AFM) has been applied in measuring circulating membrane vesicles. However, it seems very difficult for AFM to directly image/identify and measure cell-bound membrane vesicles due to the similarity of surface morphology between membrane vesicles and cell surfaces. Therefore, until now no AFM studies on cell-surface membrane vesicles have been reported. In this study, we found that air drying can induce the transformation of most cell-surface membrane vesicles into pits that are more readily detectable by AFM. Based on this, we developed an AFM-based pit-measuring method and, for the first time, used AFM to indirectly measure cell-surface membrane vesicles on cultured endothelial cells. Using this approach, we observed and quantitatively measured at least two populations of cell-surface membrane vesicles, a nanoscale population (<500 nm in diameter peaking at ∼250 nm) and a microscale population (from 500 nm to ∼2 μm peaking at ∼0.8 μm), whereas confocal microscopy only detected the microscale population. The AFM-based pit-measuring method is potentially useful for studying cell-surface membrane vesicles and for investigating the mechanisms of membrane vesicle formation/release

  17. Feasibility study of using a 'travelling' CO2 and CH4 instrument to validate continuous in-situ measurement stations

    Energy Technology Data Exchange (ETDEWEB)

    Hammer, S.; Konrad, G.; Levin, I. [Institut fuer Umweltphysik IUP, Heidelberg University (Germany); Vermeulen, A.T. [Energy research Center of the Netherlands ECN, Petten (Netherlands); Laurent, O.; Delmotte, M.; Hazan, L. [Laboratoire des Sciences du Climat et de l' Environnement LSCE, Gif-sur-Yvette (France); Jordan, A. [Max Planck Institute for Biogeochemistry, Jena (Germany); Conil, S. [Agence Nationale pour la gestion des Dechets Radioactifs ANDRA, Bure (France)

    2012-09-24

    In the course of the ICOS (Integrated Carbon Observation System) Demo Experiment a feasibility study on the usefulness of a Travelling Comparison Instrument (TCI) was conducted in order to evaluate continuous atmospheric CO2 and CH4 measurements at two European stations. The aim of the TCI is to independently measure ambient air in parallel to the standard station instrumentation, thus providing a comprehensive comparison that includes the sample intake system, the instrument itself as well as its calibration and data evaluation. Observed differences between the TCI and the Heidelberg gas chromatographic system, which acted as a reference for the TCI, were -0.02{+-}0.08{mu}mol mol{sup -1} for CO2 and -0.3{+-}2.3{mu}mol mol{sup -1} for CH4. Over a period of two weeks each, the continuous CO2 and CH4 measurements at two ICOS field stations, Cabauw and OPE, were compared to co-located TCI measurements. At Cabauw mean differences of 0.21{+-}0.06{mu}mol mol{sup -1} for CO2 and 0.41{+-}0.50{mu}mol mol{sup -1} for CH4 were found. For OPE the mean differences were 0.13{+-}0.07{mu}mol mol{sup -1} for CO2 and 0.44{+-}0.36{mu}mol mol{sup -1} for CH4. Potential causes of these observed differences are leakages or contaminations in the intake lines and/or there flushing pumps. At Cabauw station an additional error contribution originates from insufficient flushing of standard gases. Offsets arising from differences in the working standard calibrations or leakages/ contaminations in the drying systems are too small to explain the observed differences. Finally a comprehensive quality management strategy for atmospheric monitoring networks is proposed.

  18. Oxidation of clean silicon surfaces studied by four-point probe surface conductance measurements

    DEFF Research Database (Denmark)

    Petersen, Christian Leth; Grey, Francois; Aono, M.

    1997-01-01

    We have investigated how the conductance of Si(100)-(2 x 1) and Si(111)-(7 x 7) surfaces change during exposure to molecular oxygen. A monotonic decrease in conductance is seen as the (100) surfaces oxidizes. In contract to a prior study, we propose that this change is caused by a decrease in sur...

  19. Air and radiation monitoring stations

    CERN Multimedia

    AUTHOR|(SzGeCERN)582709

    2015-01-01

    CERN has around 100 monitoring stations on and around its sites. New radiation measuring stations, capable of detecting even lower levels of radiation, were installed in 2014. Two members of HE-SEE group (Safety Engineering and Environment group) in front of one of the new monitoring stations.

  20. Calibration of GOES-derived solar radiation data using a distributed network of surface measurements in Florida, USA

    Science.gov (United States)

    Sumner, David M.; Pathak, Chandra S.; Mecikalski, John R.; Paech, Simon J.; Wu, Qinglong; Sangoyomi, Taiye; Babcock, Roger W.; Walton, Raymond

    2008-01-01

    Solar radiation data are critically important for the estimation of evapotranspiration. Analysis of visible-channel data derived from Geostationary Operational Environmental Satellites (GOES) using radiative transfer modeling has been used to produce spatially- and temporally-distributed datasets of solar radiation. An extensive network of (pyranometer) surface measurements of solar radiation in the State of Florida has allowed refined calibration of a GOES-derived daily integrated radiation data product. This refinement of radiation data allowed for corrections of satellite sensor drift, satellite generational change, and consideration of the highly-variable cloudy conditions that are typical of Florida. To aid in calibration of a GOES-derived radiation product, solar radiation data for the period 1995–2004 from 58 field stations that are located throughout the State were compiled. The GOES radiation product was calibrated by way of a three-step process: 1) comparison with ground-based pyranometer measurements on clear reference days, 2) correcting for a bias related to cloud cover, and 3) deriving month-by-month bias correction factors. Pre-calibration results indicated good model performance, with a station-averaged model error of 2.2 MJ m–2 day–1 (13 percent). Calibration reduced errors to 1.7 MJ m–2 day–1 (10 percent) and also removed time- and cloudiness-related biases. The final dataset has been used to produce Statewide evapotranspiration estimates.

  1. Leidenfrost drops cooling surfaces: theory and interferometric measurement

    NARCIS (Netherlands)

    Van Limbeek, Michiel A. J.; Klein Schaarsberg, Martin H.; Sobac, Benjamin; Rednikov, Alexey; Sun, Chao; Colinet, Pierre; Lohse, Detlef

    2017-01-01

    When a liquid drop is placed on a highly superheated surface, it can be levitated by its own vapour. This remarkable phenomenon is referred to as the Leidenfrost effect. The thermally insulating vapour film results in a severe reduction of the heat transfer rate compared to experiments at lower

  2. Surface and Flow Field Measurements on the FAITH Hill Model

    Science.gov (United States)

    Bell, James H.; Heineck, James T.; Zilliac, Gregory; Mehta, Rabindra D.; Long, Kurtis R.

    2012-01-01

    A series of experimental tests, using both qualitative and quantitative techniques, were conducted to characterize both surface and off-surface flow characteristics of an axisymmetric, modified-cosine-shaped, wall-mounted hill named "FAITH" (Fundamental Aero Investigates The Hill). Two separate models were employed: a 6" high, 18" base diameter machined aluminum model that was used for wind tunnel tests and a smaller scale (2" high, 6" base diameter) sintered nylon version that was used in the water channel facility. Wind tunnel and water channel tests were conducted at mean test section speeds of 165 fps (Reynolds Number based on height = 500,000) and 0.1 fps (Reynolds Number of 1000), respectively. The ratio of model height to boundary later height was approximately 3 for both tests. Qualitative techniques that were employed to characterize the complex flow included surface oil flow visualization for the wind tunnel tests, and dye injection for the water channel tests. Quantitative techniques that were employed to characterize the flow included Cobra Probe to determine point-wise steady and unsteady 3D velocities, Particle Image Velocimetry (PIV) to determine 3D velocities and turbulence statistics along specified planes, Pressure Sensitive Paint (PSP) to determine mean surface pressures, and Fringe Imaging Skin Friction (FISF) to determine surface skin friction (magnitude and direction). This initial report summarizes the experimental set-up, techniques used, data acquired and describes some details of the dataset that is being constructed for use by other researchers, especially the CFD community. Subsequent reports will discuss the data and their interpretation in more detail

  3. Radiation Measured with Different Dosimeters for ISS-Expedition 18-19/ULF2 on Board International Space Station during Solar Minimum

    Science.gov (United States)

    Zhou, Dazhuang; Gaza, R.; Roed, Y.; Semones, E.; Lee, K.; Steenburgh, R.; Johnson, S.; Flanders, J.; Zapp, N.

    2010-01-01

    Radiation field of particles in low Earth orbit (LEO) is mainly composed of galactic cosmic rays (GCR), solar energetic particles and particles in SAA (South Atlantic Anomaly). GCR are modulated by solar activity, at the period of solar minimum activity, GCR intensity is at maximum and the main contributor for space radiation is GCR. At present for space radiation measurements conducted by JSC (Johnson Space Center) SRAG (Space Radiation Analysis Group), the preferred active dosimeter sensitive to all LET (Linear Energy Transfer) is the tissue equivalent proportional counter (TEPC); the preferred passive dosimeters are thermoluminescence dosimeters (TLDs) and optically stimulated luminescence dosimeters (OSLDs) sensitive to low LET as well as CR-39 plastic nuclear track detectors (PNTDs) sensitive to high LET. For the method using passive dosimeters, radiation quantities for all LET can be obtained by combining radiation results measured with TLDs/OSLDs and CR-39 PNTDs. TEPC, TLDs/OSLDs and CR-39 detectors were used to measure the radiation field for the ISS (International Space Station) - Expedition 18-19/ULF2 space mission which was conducted from 15 November 2008 to 31 July 2009 - near the period of the recent solar minimum activity. LET spectra (differential and integral fluence, absorbed dose and dose equivalent) and radiation quantities were measured for positions TEPC, TESS (Temporary Sleeping Station, inside the polyethylene lined sleep station), SM-P 327 and 442 (Service Module - Panel 327 and 442). This paper presents radiation LET spectra measured with TEPC and CR-39 PNTDs and radiation dose measured with TLDs/OSLDs as well as the radiation quantities combined from results measured with passive dosimeters.

  4. 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

  5. Current Options for Measuring the Surface Temperature of Dairy Cattle in a Stable Technology: Review

    Directory of Open Access Journals (Sweden)

    Kateřina Švejdová

    2016-05-01

    Full Text Available Regular measurement of the body surface temperature can help to assess the health status of animals. There are many technological possibilities of contactless temperature measurement of body surface. The important thing is to find the right part of the body whose temperature will point to the first possible symptoms and immediately react to the first signs of the disease. Disagreements about how to measure body surface temperature and accuracy of the method can occur when different measures are used. We review work showing possibilities of contactless surface temperature measurements using 1 thermography, 2 electronic transponders and 3 other possibilities of measuring the body surface temperature of dairy cattle. For example, when we scan the surface temperature with the thermal imager there can operate in individual animals confounding factors such as the nature or degree of muscular coat, which may significantly affect the results.

  6. Measurement of the surface susceptibility and the surface conductivity of atomically thin by spectroscopic ellipsometry

    KAUST Repository

    Jayaswal, Gaurav; Dai, Zhenyu; Zhang, Xixiang; Bagnarol, Mirko; Martucci, Alessandro; Merano, Michele

    2017-01-01

    We show how to correctly extract from the ellipsometric data the surface susceptibility and the surface conductivity that describe the optical properties of monolayer $\\rm MoS_2$. Theoretically, these parameters stem from modelling a single-layer two-dimensional crystal as a surface current, a truly two-dimensional model. Currently experimental practice is to consider this model equivalent to a homogeneous slab with an effective thickness given by the interlayer spacing of the exfoliating bulk material. We prove that the error in the evaluation of the surface susceptibility of monolayer $\\rm MoS_2$, owing to the use of the slab model, is at least 10% or greater, a significant discrepancy in the determination of the optical properties of this material.

  7. Measurement of the surface susceptibility and the surface conductivity of atomically thin by spectroscopic ellipsometry

    KAUST Repository

    Jayaswal, Gaurav

    2017-10-01

    We show how to correctly extract from the ellipsometric data the surface susceptibility and the surface conductivity that describe the optical properties of monolayer $\\ m MoS_2$. Theoretically, these parameters stem from modelling a single-layer two-dimensional crystal as a surface current, a truly two-dimensional model. Currently experimental practice is to consider this model equivalent to a homogeneous slab with an effective thickness given by the interlayer spacing of the exfoliating bulk material. We prove that the error in the evaluation of the surface susceptibility of monolayer $\\ m MoS_2$, owing to the use of the slab model, is at least 10% or greater, a significant discrepancy in the determination of the optical properties of this material.

  8. Measurement noise of a point autofocus surface topography instrument

    DEFF Research Database (Denmark)

    Feng, Xiaobing; Quagliotti, Danilo; Maculotti, Giacomo

    Optical instruments for areal topography measurement can be especially sensitive to noise when scanning is required. Such noise has different sources, including those internally generated and external sources from the environment.......Optical instruments for areal topography measurement can be especially sensitive to noise when scanning is required. Such noise has different sources, including those internally generated and external sources from the environment....

  9. Source attribution of Arctic black carbon constrained by aircraft and surface measurements

    Directory of Open Access Journals (Sweden)

    J.-W. Xu

    2017-10-01

    Full Text Available Black carbon (BC contributes to Arctic warming, yet sources of Arctic BC and their geographic contributions remain uncertain. We interpret a series of recent airborne (NETCARE 2015; PAMARCMiP 2009 and 2011 campaigns and ground-based measurements (at Alert, Barrow and Ny-Ålesund from multiple methods (thermal, laser incandescence and light absorption with the GEOS-Chem global chemical transport model and its adjoint to attribute the sources of Arctic BC. This is the first comparison with a chemical transport model of refractory BC (rBC measurements at Alert. The springtime airborne measurements performed by the NETCARE campaign in 2015 and the PAMARCMiP campaigns in 2009 and 2011 offer BC vertical profiles extending to above 6 km across the Arctic and include profiles above Arctic ground monitoring stations. Our simulations with the addition of seasonally varying domestic heating and of gas flaring emissions are consistent with ground-based measurements of BC concentrations at Alert and Barrow in winter and spring (rRMSE  < 13 % and with airborne measurements of the BC vertical profile across the Arctic (rRMSE  = 17 % except for an underestimation in the middle troposphere (500–700 hPa.Sensitivity simulations suggest that anthropogenic emissions in eastern and southern Asia have the largest effect on the Arctic BC column burden both in spring (56 % and annually (37 %, with the largest contribution in the middle troposphere (400–700 hPa. Anthropogenic emissions from northern Asia contribute considerable BC (27 % in spring and 43 % annually to the lower troposphere (below 900 hPa. Biomass burning contributes 20 % to the Arctic BC column annually.At the Arctic surface, anthropogenic emissions from northern Asia (40–45 % and eastern and southern Asia (20–40 % are the largest BC contributors in winter and spring, followed by Europe (16–36 %. Biomass burning from North America is the most important

  10. Correlation and uncertainties evaluation in backscattering of entrance surface air kerma measurements

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, G.J.; Sousa, C.H.S.; Peixoto, J.G.P., E-mail: gt@ird.gov.br [Instituto de Radioproteção e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    The air kerma measurement is important to verify the applied doses in radiodiagnostic. The literature determines some methods to measure the entrance surface air kerma or entrance surface dose but some of this methods may increase the measurement with the backscattering. Were done setups of measurements to do correlations between them. The expanded uncertainty exceeded 5% for measurements with backscattering, reaching 8.36%, while in situations where the backscattering was avoided, the uncertainty was 3.43%. (author)

  11. Commencement measurements giving fundamental surface tension determinations in tensiometry

    International Nuclear Information System (INIS)

    Carbery, D; Morrin, D; O'Rourke, B; McMillan, N D; O'Neill, M; Riedel, S; Pringuet, P; Smith, S R P

    2011-01-01

    This study provides experimental testing of a ray-tracing model of the tensiotrace that explores the measurement potential of a well-defined optical position in the tensiotrace signal known as the 'commencement'. This point is defined as the first measureable optical coupling in the fiber drophead between source and collector fibers for light injected inside a growing drop. Tensiotrace ray-tracing model is briefly introduced. Empirical relationships of commencement measures from a wide-ranging study are presented. A number of conclusions can be drawn from the successful linking of computer predictions to these experimental relationships.

  12. The Effect of Warming Oceans at a Tide Gauge Station

    OpenAIRE

    Bâki Iz H.

    2016-01-01

    This study proposes a new paradigm for assessing thermosteric effects of warming oceans at a tide gauge station. For demonstration, the trend due to the global thermosteric sea level at the Key West, FL tide gauge station was estimated using the tide gauge measurements and the global sea surface temperature anomalies that were represented by yearly distributed lags. A comparison of the estimate with the trend estimate from a descriptive model revealed that 0.7±0.1 mm/y...

  13. Seasonal variability of surface and column carbon monoxide over the megacity Paris, high-altitude Jungfraujoch and Southern Hemispheric Wollongong stations

    Science.gov (United States)

    Té, Yao; Jeseck, Pascal; Franco, Bruno; Mahieu, Emmanuel; Jones, Nicholas; Paton-Walsh, Clare; Griffith, David W. T.; Buchholz, Rebecca R.; Hadji-Lazaro, Juliette; Hurtmans, Daniel; Janssen, Christof

    2016-09-01

    This paper studies the seasonal variation of surface and column CO at three different sites (Paris, Jungfraujoch and Wollongong), with an emphasis on establishing a link between the CO vertical distribution and the nature of CO emission sources. We find the first evidence of a time lag between surface and free tropospheric CO seasonal variations in the Northern Hemisphere. The CO seasonal variability obtained from the total columns and free tropospheric partial columns shows a maximum around March-April and a minimum around September-October in the Northern Hemisphere (Paris and Jungfraujoch). In the Southern Hemisphere (Wollongong) this seasonal variability is shifted by about 6 months. Satellite observations by the IASI-MetOp (Infrared Atmospheric Sounding Interferometer) and MOPITT (Measurements Of Pollution In The Troposphere) instruments confirm this seasonality. Ground-based FTIR (Fourier transform infrared) measurements provide useful complementary information due to good sensitivity in the boundary layer. In situ surface measurements of CO volume mixing ratios at the Paris and Jungfraujoch sites reveal a time lag of the near-surface seasonal variability of about 2 months with respect to the total column variability at the same sites. The chemical transport model GEOS-Chem (Goddard Earth Observing System chemical transport model) is employed to interpret our observations. GEOS-Chem sensitivity runs identify the emission sources influencing the seasonal variation of CO. At both Paris and Jungfraujoch, the surface seasonality is mainly driven by anthropogenic emissions, while the total column seasonality is also controlled by air masses transported from distant sources. At Wollongong, where the CO seasonality is mainly affected by biomass burning, no time shift is observed between surface measurements and total column data.

  14. Modification and optimisation measures on the demineralisation plant of the Boxberg Power Station; Umbau und Optimierung der Vollentsalzungsanlage im Kraftwerk Boxberg

    Energy Technology Data Exchange (ETDEWEB)

    Leidich, F.U. [ALSTOM Power Generation AG, Mannheim (Germany); Markert, A. [Vattenfall Europe Generation AG Co KG, E-KT, Cottbus (Germany); Hajdamowicz, S. [Vattenfall Europe Generation AG Co KG, E-GBB, Boxberg (Germany); Kleespies, W. [RoKa GmbH, Butzbach (Germany)

    2006-07-01

    The demineralisation plant at the Boxberg Power Station, Unit AQ (Plant IV), owned by Vattenfall Europe Generation AG and Co KG, officially started its operation in 2000. In the course of the operation, technical shortcomings became apparent that rendered the quality of the deionised water inadequate and did prevent the plant from being operated in a normal, fully-automatic mode. Due to the insolvency of the supplier, it had not been possible to eliminate a series of problems and optimise the processes in such a way that the plant could be operated as planned. Nevertheless, thanks to measures like retrofitting the system with lowering loops, replacing the regenerating stations by frequency-controlled excenter-screw propeller pumps, installing automatic vents, and optimising the control concept of the plant, it finally was possible to solve some of the main problems. Longer intervals between regenerating procedures came as an additional benefit. (orig.)

  15. Inferring Shallow Subsurface Density Structure from Surface and Underground Gravity Measurements: Calibrating Models for Relatively Undeformed Volcanic Strata at the Jemez Volcanic Field, New Mexico, USA

    Science.gov (United States)

    Roy, Mousumi; Lewis, Megan; Johnson, Alex; George, Nicolas; Rowe, Charlotte; Guardincerri, Elena

    2018-03-01

    Imaging shallow subsurface density structure is an important goal in a variety of applications, from hydrogeology to seismic and volcanic hazard assessment. We assess the effectiveness of surface and subsurface gravity measurements in estimating the density structure of a well-characterized rock volume: the mesa (a small, flat-topped plateau) upon which the town of Los Alamos, New Mexico, USA is located. Our gravity measurements were made on the mesa surface above a horizontal tunnel and underground, within the tunnel. We demonstrate that, in the absence of other geophysical data such as seismic data or muon attenuation, subsurface (tunnel) gravity measurements are critical to accurately recovering geologic structure. Without the tunnel data, our resolution is limited to roughly the surface gravity station spacing, but by including the tunnel data we can resolve structure to a depth of 10 times the surface gravity station spacing. Densities were obtained using both forward modeling and a Bayesian inverse modeling approach, incorporating relevant constraints from geologic observations. We find that Bayesian inversion, with geologically relevant prior, is a superior approach to the forward models in terms of both robustness and efficiency and correctly predicts the orientation and elevation of important geologic features.

  16. Time-Resolved Surface Temperature Measurement for Pulsed Ablative Thrusters

    National Research Council Canada - National Science Library

    Antonsen, Erik

    2003-01-01

    .... The diagnostic draws on heritage from the experimental dynamic crack propagation community which has used photovoltaic infrared detectors to measure temperature rise in materials in the process of fracture...

  17. Earth System Research Laboratory Long-Term Surface Aerosol Measurements

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Aerosol measurements began at the NOAA Earth System Research Laboratory (ESRL) Global Monitoring Division (GMD) baseline observatories in the mid-1970's with the...

  18. Measurement of gamma ray flux within the containment building at the first unit of Kori nuclear power station

    Energy Technology Data Exchange (ETDEWEB)

    Kim, T. W.; Kim, K. D.; Yoon, C. H.; Han, J. M.; Hu, Y. H. [Korea Hydraulic and Nuclear Power Company, Taejon (Korea, Republic of)

    2004-07-01

    To evaluate gamma ray dose response of GM counter being used for monitoring of gamma ray field in nuclear power plants, gamma ray energy spectra and fluxes were obtained for three positions at the unit 1 of the Kori nuclear power station. By applying the response values of Eberline's E112B survey meter to the results, the doses represented on the survey meter were overestimated from 1.31 to 1.37 times when compared to the real doses for these three positions.

  19. Performance verification of focus variation and confocal microscopes measuring tilted ultra-fine surfaces

    DEFF Research Database (Denmark)

    Quagliotti, Danilo; Baruffi, Federico; Tosello, Guido

    2016-01-01

    The behaviour of two optical instruments, scilicet a laser scanning confocal microscope and a focus-variation microscope, was investigated considering measurements of tilted surfaces. The measured samples were twelve steel artefacts for mould surface finish reference, covering Sa roughness...... parameter in the range (101—103) nm. The 3D surface texture parameters considered were Sa, Sq and Sdq. The small working distance of the confocal microscope objectives influenced the measurement setup, preventing from selecting a high tilting angle. The investigation was carried out comparing measurements...... of flat surfaces (0° tilt) with measurements of 12.5° tilted surfaces. The confocal microscope results showed a high sensitivity to tilting due to the laser beam reflection on the metal surfaces. The focus variation microscope results were more robust with respect to the considered angular variation...

  20. Sea level: measuring the bounding surfaces of the ocean

    Science.gov (United States)

    Tamisiea, Mark E.; Hughes, Chris W.; Williams, Simon D. P.; Bingley, Richard M.

    2014-01-01

    The practical need to understand sea level along the coasts, such as for safe navigation given the spatially variable tides, has resulted in tide gauge observations having the distinction of being some of the longest instrumental ocean records. Archives of these records, along with geological constraints, have allowed us to identify the century-scale rise in global sea level. Additional data sources, particularly satellite altimetry missions, have helped us to better identify the rates and causes of sea-level rise and the mechanisms leading to spatial variability in the observed rates. Analysis of all of the data reveals the need for long-term and stable observation systems to assess accurately the regional changes as well as to improve our ability to estimate future changes in sea level. While information from many scientific disciplines is needed to understand sea-level change, this review focuses on contributions from geodesy and the role of the ocean's bounding surfaces: the sea surface and the Earth's crust. PMID:25157196

  1. Sea level: measuring the bounding surfaces of the ocean.

    Science.gov (United States)

    Tamisiea, Mark E; Hughes, Chris W; Williams, Simon D P; Bingley, Richard M

    2014-09-28

    The practical need to understand sea level along the coasts, such as for safe navigation given the spatially variable tides, has resulted in tide gauge observations having the distinction of being some of the longest instrumental ocean records. Archives of these records, along with geological constraints, have allowed us to identify the century-scale rise in global sea level. Additional data sources, particularly satellite altimetry missions, have helped us to better identify the rates and causes of sea-level rise and the mechanisms leading to spatial variability in the observed rates. Analysis of all of the data reveals the need for long-term and stable observation systems to assess accurately the regional changes as well as to improve our ability to estimate future changes in sea level. While information from many scientific disciplines is needed to understand sea-level change, this review focuses on contributions from geodesy and the role of the ocean's bounding surfaces: the sea surface and the Earth's crust. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  2. Remote measurement of surface roughness, surface reflectance, and body reflectance with LiDAR.

    Science.gov (United States)

    Li, Xiaolu; Liang, Yu

    2015-10-20

    Light detection and ranging (LiDAR) intensity data are attracting increasing attention because of the great potential for use of such data in a variety of remote sensing applications. To fully investigate the data potential for target classification and identification, we carried out a series of experiments with typical urban building materials and employed our reconstructed built-in-lab LiDAR system. Received intensity data were analyzed on the basis of the derived bidirectional reflectance distribution function (BRDF) model and the established integration method. With an improved fitting algorithm, parameters involved in the BRDF model can be obtained to depict the surface characteristics. One of these parameters related to surface roughness was converted to a most used roughness parameter, the arithmetical mean deviation of the roughness profile (Ra), which can be used to validate the feasibility of the BRDF model in surface characterizations and performance evaluations.

  3. Measurement of the interaction between the flow and the free surface of a liquid

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Koji [Univ. of Tokyo, Ibaraki (Japan); Schmidl, W.D.; Philip, O.G. [Texas A& M Univ., College Station, TX (United States)

    1995-09-01

    The interaction between the flow and free surface was evaluated measuring the velocity distribution and surface movement simultaneously. The test section was a rectangular tank having a free surface. A rectangular nozzle was set near the free surface, causing the wavy free surface condition. The flow under the free surface was visualized by a laser light sheet and small tracer particles. With image processing techniques, the movement of the free surface and the movement of the particles were simultaneously measured from the recorded images, resulting in the velocity distributions and surface locations. Then, the interactions between the flow and free surface were evaluated using the form of turbulent energy and surface-related turbulent values. By increasing the turbulent energy near the free surface, the fluctuations of the free surface height and the inclination of the free surface were increased. The higher fluctuation of horizontal velocity was related to the higher surface position and negative inclination. The image processing technique is found to be very useful to evaluate the interaction between free surface and flow.

  4. Measurement of the interaction between the flow and the free surface of a liquid

    International Nuclear Information System (INIS)

    Okamoto, Koji; Schmidl, W.D.; Philip, O.G.

    1995-01-01

    The interaction between the flow and free surface was evaluated measuring the velocity distribution and surface movement simultaneously. The test section was a rectangular tank having a free surface. A rectangular nozzle was set near the free surface, causing the wavy free surface condition. The flow under the free surface was visualized by a laser light sheet and small tracer particles. With image processing techniques, the movement of the free surface and the movement of the particles were simultaneously measured from the recorded images, resulting in the velocity distributions and surface locations. Then, the interactions between the flow and free surface were evaluated using the form of turbulent energy and surface-related turbulent values. By increasing the turbulent energy near the free surface, the fluctuations of the free surface height and the inclination of the free surface were increased. The higher fluctuation of horizontal velocity was related to the higher surface position and negative inclination. The image processing technique is found to be very useful to evaluate the interaction between free surface and flow

  5. Tire-to-Surface Friction-Coefficient Measurements with a C-123B Airplane on Various Runway Surfaces

    Science.gov (United States)

    Sawyer, Richard H.; Kolnick, Joseph J.

    1959-01-01

    An investigation was conducted to obtain information on the tire-to-surface friction coefficients available in aircraft braking during the landing run. The tests were made with a C-123B airplane on both wet and dry concrete and bituminous pavements and on snow-covered and ice surfaces at speeds from 12 to 115 knots. Measurements were made of the maximum (incipient skidding) friction coefficient, the full-skidding (locked wheel) friction coefficient, and the wheel slip ratio during braking.

  6. High-speed 3D surface measurement with mechanical projector

    Science.gov (United States)

    Hyun, Jae-Sang; Zhang, Song

    2017-05-01

    This paper presents a method to overcome the light spectral range limitation of using digital-light-processing (DLP) projector for 3D shape measurement by developing a mechanical projector. The mechanical projector enables much broader spectral range of light than that the DLP projector allows. The rapidly spinning disk with binary structures can generate desired sinusoidal patterns at a frequency of 10 kHz or higher with a single DC motor. By precisely synchronizing the camera with the projector, phase-shifted fringe patterns can be accurately captured for high-accuracy 3D shape measurement. We further employed a computational framework that could enable absolute phase and thus absolute 3D shape measurement. We developed such prototype system that experimentally demonstrated the success of the proposed method.

  7. Evaluation of the Street Pollution Model OSPM for Measurements at 12 Streets Stations Using a Newly Developed and Freely Available Evaluation Tool

    DEFF Research Database (Denmark)

    Ketzel, Matthias; Jensen, Steen Solvang; Brandt, Jørgen

    2012-01-01

    In the present work, the Operational Street Pollution Model (OSPM) has been evaluated in comparison with continuous half-hourly measurements over a multi-year period for five permanent street monitor stations that constitute part of the Danish Air Quality Monitoring Programme as well as with pass......In the present work, the Operational Street Pollution Model (OSPM) has been evaluated in comparison with continuous half-hourly measurements over a multi-year period for five permanent street monitor stations that constitute part of the Danish Air Quality Monitoring Programme as well...... the observations well, especially for the most recent years, while for NO2 the model over-predicts in two cases. The explanation for this over-prediction is believed to be uncertainties in the traffic or emission input data, but also in model parameters, and the representativeness of the urban background data may....... OSPM calculations for nine streets with passive sampler measurements were conducted as ‘blind test’ i.e. without knowing the measured values. OSPM calculations were in good agreement with the measurements for seven out of nine street sections. Refinements of the input data lead to a significant...

  8. Characterization of the Micro-shell Surface Using Holographic Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Sandras, F.; Hermerel, C.; Choux, A.; Merillot, P.; Pin, G.; Jeannot, L. [CEA Valduc, Dept Rech Mat Nucl, Serv Microcibles, 21 - Is-sur-Tille (France)

    2009-05-15

    To characterize the shape, the quality, and the roughness of micro-shells, typically used technologies are scanning electron microscopy, scanning interferometric microscopy, or atomic force microscopy. One of the drawbacks of these techniques is that they are generally slow because of their scanning process. Digital holographic microscopy technology is an innovation that can offer ability adapted to these studies. It captures holograms instead of intensity images, as done by conventional microscopes. The holograms are then digitally interpreted (10 per second) to reconstruct a double image, one for the intensity and another one for the phase. Using a rotation axis, the bump counting for the complete micro-shell surface is possible with a very high speed. Using an image stitching software, mapping can be done in a few minutes. Wavelets such as 'Mexican hat' are used to model the bumps. Each bump can then be characterized on the map by its position, diameter, and height. (authors)

  9. Measuring surface current velocities in the Agulhas region with ASAR

    CSIR Research Space (South Africa)

    Rouault, MJ

    2010-01-01

    Full Text Available is known to perform well. Although radial velocities derived from ASAR are on occasion able to represent the measured flow with incredible accuracy, the overall performance of the ASAR radial velocity product is negatively impacted by a few very large...

  10. Measurement of adhesion properties between topcoat paint and metallized/galvanized steel with surface energy measurement equipment.

    Science.gov (United States)

    2013-09-01

    The objectives of this research project are: (1) Compare the adhesion properties of NEPCOAT-approved topcoat paint over : metallized or galvanized steel. Use surface-energy measuring technique to characterize the wetting properties of the liqui...

  11. An objective device for measuring surface roughness of skin and scars

    NARCIS (Netherlands)

    Bloemen, Monica C. T.; van Gerven, Maaike S.; van der Wal, Martijn B. A.; Verhaegen, Pauline D. H. M.; Middelkoop, Esther

    2011-01-01

    Scar formation remains a major clinical problem; therefore, various therapies have been developed to improve scar quality. To evaluate the effectiveness of these therapies, objective measurement tools are necessary. An appropriate, objective measuring instrument for assessment of surface roughness

  12. An objective device for measuring surface roughness of skin and scars

    NARCIS (Netherlands)

    Bloemen, M.C.T.; van Gerven, M.S.; van der Wal, M.B.A.; Verhaegen, P.D.H.M.; Middelkoop, E.

    2011-01-01

    Background: Scar formation remains a major clinical problem; therefore, various therapies have been developed to improve scar quality. To evaluate the effectiveness of these therapies, objective measurement tools are necessary. An appropriate, objective measuring instrument for assessment of surface

  13. Direct measurement of surface-state conductance by microscopic four-point probe method

    DEFF Research Database (Denmark)

    Hasegawa, S.; Shiraki, I.; Tanikawa, T.

    2002-01-01

    For in situ measurements of local electrical conductivity of well defined crystal surfaces in ultrahigh vacuum, we have developed microscopic four-point probes with a probe spacing of several micrometres, installed in a scanning-electron - microscope/electron-diffraction chamber. The probe...... is precisely positioned on targeted areas of the sample surface by using piezoactuators. This apparatus enables conductivity measurement with extremely high surface sensitivity, resulting in direct access to surface-state conductivity of the surface superstructures, and clarifying the influence of atomic steps...

  14. Station Capacity

    DEFF Research Database (Denmark)

    Landex, Alex

    2011-01-01

    the probability of conflicts and the minimum headway times into account. The last method analyzes how optimal platform tracks are used by examining the arrival and departure pattern of the trains. The developed methods can either be used separately to analyze specific characteristics of the capacity of a station......Stations are often limiting the capacity of railway networks. This is due to extra need of tracks when trains stand still, trains turning around, and conflicting train routes. Although stations are often the capacity bottlenecks, most capacity analysis methods focus on open line capacity. Therefore...... for platform tracks and the probability that arriving trains will not get a platform track immediately at arrival. The third method is a scalable method that analyzes the conflicts in the switch zone(s). In its simplest stage, the method just analyzes the track layout while the more advanced stages also take...

  15. Comparison of diffusion charging and mobility-based methods for measurement of aerosol agglomerate surface area.

    Science.gov (United States)

    Ku, Bon Ki; Kulkarni, Pramod

    2012-05-01

    We compare different approaches to measure surface area of aerosol agglomerates. The objective was to compare field methods, such as mobility and diffusion charging based approaches, with laboratory approach, such as Brunauer, Emmett, Teller (BET) method used for bulk powder samples. To allow intercomparison of various surface area measurements, we defined 'geometric surface area' of agglomerates (assuming agglomerates are made up of ideal spheres), and compared various surface area measurements to the geometric surface area. Four different approaches for measuring surface area of agglomerate particles in the size range of 60-350 nm were compared using (i) diffusion charging-based sensors from three different manufacturers, (ii) mobility diameter of an agglomerate, (iii) mobility diameter of an agglomerate assuming a linear chain morphology with uniform primary particle size, and (iv) surface area estimation based on tandem mobility-mass measurement and microscopy. Our results indicate that the tandem mobility-mass measurement, which can be applied directly to airborne particles unlike the BET method, agrees well with the BET method. It was also shown that the three diffusion charging-based surface area measurements of silver agglomerates were similar within a factor of 2 and were lower than those obtained from the tandem mobility-mass and microscopy method by a factor of 3-10 in the size range studied. Surface area estimated using the mobility diameter depended on the structure or morphology of the agglomerate with significant underestimation at high fractal dimensions approaching 3.

  16. Surface topography measurement by frequency sweeping digital holography.

    Czech Academy of Sciences Publication Activity Database

    Lédl, Vít; Psota, Pavel; Kaván, František; Matoušek, Ondřej; Mokrý, Pavel

    2017-01-01

    Roč. 56, č. 28 (2017), s. 7808-7814 ISSN 1559-128X R&D Projects: GA MŠk(CZ) LO1206; GA ČR(CZ) GA16-11965S Institutional support: RVO:61389021 Keywords : Wavelenght Scanning Interferometry * Shape measurement * Profilomerty Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering OBOR OECD: Electrical and electronic engineering Impact factor: 1.650, year: 2016 https://doi.org/10.1364/AO.56.007808

  17. Monitoring Induced Fractures with Electrical Measurements using Depth to Surface Resistivity: A Field Case Study

    Science.gov (United States)

    Wilt, M.; Nieuwenhuis, G.; Sun, S.; MacLennan, K.

    2016-12-01

    Electrical methods offer an attractive option to map induced fractures because the recovered anomaly is related to the electrical conductivity of the injected fluid in the open (propped) section of the fracture operation. This is complementary to existing micro-seismic technology, which maps the mechanical effects of the fracturing. In this paper we describe a 2014 field case where a combination of a borehole casing electrode and a surface receiver array was used to monitor hydrofracture fracture creation and growth in an unconventional oil field project. The fracture treatment well was 1 km long and drilled to a depth of 2.2 km. Twelve fracture events were induced in 30 m intervals (stages) in the 1 km well. Within each stage 5 events (clusters) were initiated at 30 m intervals. Several of the fracture stages used a high salinity brine, instead of fresh water, to enhance the electrical signal. The electrical experiment deployed a downhole source in a well parallel to the treatment well and 100 m away. The source consisted of an electrode attached to a wireline cable into which a 0.25 Hz square wave was injected. A 60-station electrical field receiver array was placed above the fracture and extending for several km. Receivers were oriented to measure electrical field parallel with the presumed fracture direction and those perpendicular to it. Active source electrical data were collected continuously during 7 frac stages, 3 of which used brine as the frac fluid over a period of several days. Although the site was quite noisy and the electrical anomaly small we managed to extract a clear frac anomaly using field separation, extensive signal averaging and background noise rejection techniques. Preliminary 3D modeling, where we account for current distribution of the casing electrode and explicitly model multiple thin conductive sheets to represent fracture stages, produces a model consistent with the field measurements and also highlights the sensitivity of the

  18. Measurement of the specific surface area of loose copper deposit by electrochemical methods

    Directory of Open Access Journals (Sweden)

    E. A. Dolmatova

    2016-07-01

    Full Text Available In the work the surface area of the electrode with dispersed copper deposit obtained within 30 seconds was evaluated by techniques of chronopotentiometry (CPM and impedance spectroscopy. In method CPM the electrode surface available for measurement depends on the value of the polarizing current. At high currents during the transition time there is a change of surface relief that can not determine the full surface of loose deposit. The electrochemical impedance method is devoid of this shortcoming since the measurements are carried out in indifferent electrolyte in the absence of current. The area measured by the impedance is tens of times higher than the value obtained by chronopotentiometry. It is found that from a solution containing sulfuric acid the deposits form with a high specific surface area. Based on these data it was concluded that the method of impedance spectroscopy can be used to measure in situ the surface area of the dispersed copper deposits.

  19. Measurement system for special surface mapping using miniature displacement sensors

    Directory of Open Access Journals (Sweden)

    Zowade Martyna

    2018-01-01

    Full Text Available The aim of the work was to design a special system for measurements of elements with repetitive geometry or assemblies with repeating components, set in a linear patterns. The main focus was based on developing a computer program for signal analysis from variable number of miniature displacement sensors. It was set that the response for displacement of measuring tip from each sensor was a 0-5 V voltage signal with possibility of using different type of sensors. Requirements were determined based on projected measurement method. A special design of sensor was made for testing the computer program. If the characteristics of the sensor is known, it is possible to compute the type A evaluation of uncertainty. The results are presented in XY chart on computer screen. The program allows the user to choose any number of the sensors and determine the distance between them. Also, the possibility of calibration of sensors’ set was provided. The test were conducted on a prototype handle for sensors, made on a 3D printer.

  20. Studies of non-contact methods for roughness measurements on wood surfaces

    International Nuclear Information System (INIS)

    Lundberg, I.A.S.; Porankiewicz, B.

    1995-01-01

    The quality of wood surfaces after different kinds of machining processes is a property of great importance for the wood processing industries. Present work is a study, whose objective was to evaluate different non-contact methods, for measurement of the quality of the wood surfaces by correlating them with stylus tracing. A number of Scots Pine samples were prepared by different kinds of wood machining processing. Surface roughness measurements were performed, utilizing two optical noncontact methods. The results indicate that the laser scan method can measure surface roughness on sawn wood with a sufficient degree of accuracy. (author) [de