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Sample records for spacecraft measured simultaneously

  1. Microscopic Electron Variations Measured Simultaneously By The Cluster Spacecraft

    Buckley, A. M.; Carozzi, T. D.; Gough, M. P.; Beloff, N.

    Data is used from the Particle Correlator experiments running on each of the four Cluster spacecraft so as to determine common microscopic behaviour in the elec- tron population observed over the macroscopic Cluster separations. The Cluster par- ticle correlator experiments operate by forming on board Auto Correlation Functions (ACFs) generated from short time series of electron counts obtained, as a function of electron energy, from the PEACE HEEA sensor. The information on the microscopic variation of the electron flux covers the frequency range DC up to 41 kHz (encom- passing typical electron plasma frequencies and electron gyro frequencies and their harmonics), the electron energy range is that covered by the PEACE HEEA sensor (within the range 1 eV to 26 keV). Results are presented of coherent electron struc- tures observed simultaneously by the four spacecraft in the differing plasma interac- tion regions and boundaries encountered by Cluster. As an aid to understanding the plasma interactions, use is made of numerical simulations which model both the un- derlying statistical properties of the electrons and also the manner in which particle correlator experiments operate.

  2. Simultaneous spacecraft orbit estimation and control based on GPS measurements via extended Kalman filter

    Tamer Mekky Ahmed Habib

    2013-06-01

    Full Text Available The primary aim of this work is to provide simultaneous spacecraft orbit estimation and control based on the global positioning system (GPS measurements suitable for application to the next coming Egyptian remote sensing satellites. Disturbance resulting from earth’s oblateness till the fourth order (i.e., J4 is considered. In addition, aerodynamic drag and random disturbance effects are taken into consideration.

  3. First current density measurements in the ring current region using simultaneous multi-spacecraft CLUSTER-FGM data

    C. Vallat

    2005-07-01

    Full Text Available The inner magnetosphere's current mapping is one of the key elements for current loop closure inside the entire magnetosphere. A method for directly computing the current is the multi-spacecraft curlometer technique, which is based on the application of Maxwell-Ampère's law. This requires the use of four-point magnetic field high resolution measurements. The FGM experiment on board the four Cluster spacecraft allows, for the first time, an instantaneous calculation of the magnetic field gradients and thus a measurement of the local current density. This technique requires, however, a careful study concerning all the factors that can affect the accuracy of the J estimate, such as the tetrahedral geometry of the four spacecraft, or the size and orientation of the current structure sampled. The first part of this paper is thus providing a detailed analysis of the method accuracy, and points out the limitations of this technique in the region of interest. The second part is an analysis of the ring current region, which reveals, for the first time, the large latitudinal extent of the ring current, for all magnetic activity levels, as well as the latitudinal evolution of the perpendicular (and parallel components of the current along the diffuse auroral zone. Our analysis also points out the sharp transition between two distinct plasma regions, with the existence of high diamagnetic currents at the interface, as well as the filamentation of the current inside the inner plasma sheet. A statistical study over multiple perigee passes of Cluster (at about 4 RE from the Earth reveals the azimuthal extent of the partial ring current. It also reveals that, at these distances and all along the evening sector, there isn't necessarily a strong dependence of the local current density value on the magnetic activity level. This is a direct consequence of the ring current morphology evolution, as well as the relative

  4. A Satellite Data Analysis and CubeSat Instrument Simulator Tool for Simultaneous Multi-spacecraft Measurements of Solar Energetic Particles

    Vannitsen, Jordan; Rizzitelli, Federico; Wang, Kaiti; Segret, Boris; Juang, Jyh-Ching; Miau, Jiun-Jih

    2017-12-01

    This paper presents a Multi-satellite Data Analysis and Simulator Tool (MDAST), developed with the original goal to support the science requirements of a Martian 3-Unit CubeSat mission profile named Bleeping Interplanetary Radiation Determination Yo-yo (BIRDY). MDAST was firstly designed and tested by taking into account the positions, attitudes, instruments field of view and energetic particles flux measurements from four spacecrafts (ACE, MSL, STEREO A, and STEREO B). Secondly, the simulated positions, attitudes and instrument field of view from the BIRDY CubeSat have been adapted for input. And finally, this tool can be used for data analysis of the measurements from the four spacecrafts mentioned above so as to simulate the instrument trajectory and observation capabilities of the BIRDY CubeSat. The onset, peak and end time of a solar particle event is specifically defined and identified with this tool. It is not only useful for the BIRDY mission but also for analyzing data from the four satellites aforementioned and can be utilized for other space weather missions with further customization.

  5. Simultaneous seeing measurements at Atacama

    Uraguchi, Fumihiro; Motohara, Kentaro; Doi, Mamoru; Takato, Naruhisa; Miyashita, Akihiko; Tanabe, Toshihiko; Oyabu, Shinki; Soyano, Takao

    2004-10-01

    Institute of Astronomy, University of Tokyo is now planning to build a 6.5-m optical-infrared telescope in Atacama, Chile. This project is called "Univ. Tokyo Atacama Observatory (TAO)", and the site evaluation is now under way. As a part of this evaluation process, we started an investigation to compare the astronomical seeing at Atacama with that at Mauna Kea. Here, we report preliminary results of seeing measurements at several sites in Atacama, carried out on October 2003. In order to separate the temporal and site-to-site variation of the seeing, we used two sets of Differential Image Motion Monitors (DIMMs), each of which has two pairs of 7.4 cm sub-apertures with 20.5 cm separation. Three sites were investigated; the point near the TAO weather station (4,950m), the summit of Cello Chico (5,150m) and the point at 5,430m altitude on Cello Toco. Simultaneous measurements were carried out for three half nights out of four half nights measurements. Although the amount of our data is very limited, the results suggest following: 1) Seeing becomes better and more stable as time passing to midnight (eg. From 0."7 to 0."4 at V-band). 2) Higher altitude sites show better seeing than lower altitude sites.

  6. A small spacecraft for multipoint measurement of ionospheric plasma

    Roberts, T. M.; Lynch, K. A.; Clayton, R. E.; Weiss, J.; Hampton, D. L.

    2017-07-01

    Measurement of ionospheric plasma is often performed by a single in situ device or remotely using cameras and radar. This article describes a small, low-resource, deployed spacecraft used as part of a local, multipoint measurement network. A B-field aligned sounding rocket ejects four of these spin-stabilized spacecraft in a cross pattern. In this application, each spacecraft carries two retarding potential analyzers which are used to determine plasma density, flow, and ion temperature. An inertial measurement unit and a light-emitting diode array are used to determine the position and orientation of the devices after deployment. The design of this spacecraft is first described, and then results from a recent test flight are discussed. This flight demonstrated the successful operation of the deployment mechanism and telemetry systems, provided some preliminary plasma measurements in a simple mid-latitude environment, and revealed several design issues.

  7. Simultaneous Remote Observations of Intense Reconnection Effects by DMSP and MMS Spacecraft During a Storm Time Substorm.

    Varsani, A; Nakamura, R; Sergeev, V A; Baumjohann, W; Owen, C J; Petrukovich, A A; Yao, Z; Nakamura, T K M; Kubyshkina, M V; Sotirelis, T; Burch, J L; Genestreti, K J; Vörös, Z; Andriopoulou, M; Gershman, D J; Avanov, L A; Magnes, W; Russell, C T; Plaschke, F; Khotyaintsev, Y V; Giles, B L; Coffey, V N; Dorelli, J C; Strangeway, R J; Torbert, R B; Lindqvist, P-A; Ergun, R

    2017-11-01

    During a magnetic storm on 23 June 2015, several very intense substorms took place, with signatures observed by multiple spacecraft including DMSP and Magnetospheric Multiscale (MMS). At the time of interest, DMSP F18 crossed inbound through a poleward expanding auroral bulge boundary at 23.5 h magnetic local time (MLT), while MMS was located duskward of 22 h MLT during an inward crossing of the expanding plasma sheet boundary. The two spacecraft observed a consistent set of signatures as they simultaneously crossed the reconnection separatrix layer during this very intense reconnection event. These include (1) energy dispersion of the energetic ions and electrons traveling earthward, accompanied with high electron energies in the vicinity of the separatrix; (2) energy dispersion of polar rain electrons, with a high-energy cutoff; and (3) intense inward convection of the magnetic field lines at the MMS location. The high temporal resolution measurements by MMS provide unprecedented observations of the outermost electron boundary layer. We discuss the relevance of the energy dispersion of the electrons, and their pitch angle distribution, to the spatial and temporal evolution of the boundary layer. The results indicate that the underlying magnetotail magnetic reconnection process was an intrinsically impulsive and the active X-line was located relatively close to the Earth, approximately at 16-18 R E .

  8. Simultaneous measurement of non-commuting observables

    Allahverdyan, A.E.; Balian, R.; Nieuwenhuizen, T.M.

    2010-01-01

    A dynamical model of a quantum measurement process is introduced, where the tested system S, a spin 1/2, is simultaneously coupled with two apparatuses A and A'. Alone, A would measure the component (s) over cap (z) whereas A' alone would measure (s) over cap (x). The apparatus A simulates an Ising

  9. Multichannel simultaneous magnetic induction measurement system (MUSIMITOS)

    Steffen, Matthias; Leonhardt, Steffen; Heimann, Konrad; Bernstein, Nina

    2008-01-01

    Non-contact heart and lung activity monitoring would be a desirable supplement to conventional monitoring techniques. Based on the potential of non-contact magnetic induction measurements, requirements for an adequate monitoring system were estimated. This formed the basis for the development of the presented extendable multichannel simultaneous magnetic induction measurement system (MUSIMITOS). Special focus was given to the dynamic behaviour and simultaneous multichannel measurements, so that the system allows for up to 14 receiver coils working simultaneously at 6 excitation frequencies. Moreover, a real-time software concept for online signal processing visualization in combination with a fast software demodulation is presented. Finally, first steps towards a clinical application are pointed out and technical performance as well as first in vivo measurements are presented. This paper covers some aspects previously presented in Steffen and Leonhardt (2007 Proc. 13th Int. Conf. on Electrical Bioimpedance and the 8th Conf. on Electrical Impedance Tomography, Graz 2007)

  10. Global Precipitation Measurement (GPM) Mission Core Spacecraft Systems Engineering Challenges

    Bundas, David J.; ONeill, Deborah; Field, Thomas; Meadows, Gary; Patterson, Peter

    2006-01-01

    The Global Precipitation Measurement (GPM) Mission is a collaboration between the National Aeronautics and Space Administration (NASA) and the Japanese Aerospace Exploration Agency (JAXA), and other US and international partners, with the goal of monitoring the diurnal and seasonal variations in precipitation over the surface of the earth. These measurements will be used to improve current climate models and weather forecasting, and enable improved storm and flood warnings. This paper gives an overview of the mission architecture and addresses the status of some key trade studies, including the geolocation budgeting, design considerations for spacecraft charging, and design issues related to the mitigation of orbital debris.

  11. High resolution simultaneous measurements of airborne radionuclides

    Abe, T.; Yamaguchi, Y.; Tanaka, K.; Komura, K.

    2006-01-01

    High resolution (2-3 hrs) simultaneous measurements of airborne radionuclides, 212 Pb, 210 Pb and 7 Be, have been performed by using extremely low background Ge detectors at Ogoya Underground Laboratory. We have measured above radionuclides at three monitoring points viz, 1) Low Level Radioactivity Laboratory (LLRL) Kanazawa University, 2) Shishiku Plateau (640 m MSL) located about 8 km from LLRL to investigate vertical difference of activity levels, and 3) Hegura Island (10 m MSL) located about 50 km from Noto Peninsula in the Sea of Japan to evaluate the influences of Asian continent or mainland of Japan on the variation to the activity levels. Variations of short-lived 212 Pb concentration showed noticeable time lags between at LLRL and at Shishiku Plateau. These time lags might be caused by change of height of a planetary boundary layer. On the contrary, variations of long-lived 210 Pb and 7 Be showed simultaneity at three locations because of homogeneity of these concentrations all over the area. (author)

  12. Simultaneous measurement of 3 fluctuating plasma parameters

    Carlson, A.; Giannone, L.

    1991-01-01

    Langmuir triple probes can provide simultaneous measurements of n e , T e and V pl with good temporal and spatial resolution, and therefore are especially suited to detailed investigations of plasma turbulence in the scrape-off-layer. Unfortunately, the finite tip separation coupled with the fluctuating gradients prevents a simple interpretation of the results. We have developed a method using, essentially, two or more triple probes, which allows a good estimate of the three plasma parameters and their spatial derivatives at each point of time (assuming tip separation is much less than correlation length and dimensionless fluctuation levels are much less than unity). In particular, we can unambiguously measure the temperature fluctuations and the turbulent particle and heat flux. (author) 1 fig

  13. Simultaneous measurement of 3 fluctuating plasma parameters

    Carlson, A.; Giannone, L.

    1991-01-01

    Langmuir triple probes can provide simultaneous measurements of n e , T e , and V pl with good temporal and spatial resolution, and therefore are especially suited to detailed investigations of plasma turbulence in the scrape-off-layer. Unfortunately, the finite tip separation coupled with the fluctuating gradients prevents a simple interpretation of the results. We have developed a method using, essentially, two or more triple probes, which allows a good estimate of the three plasma parameters and their spatial derivatives at each point of time (assuming tip separation is much less than correlation length and dimensionless fluctuation levels are much less than unity). In particular, we can unambiguously measure the temperature fluctuations and the turbulent particle and heat flux. (orig.)

  14. Simultaneous measurement of 3 fluctuating plasma parameters

    Carlson, A; Giannone, L. (Max-Planck-Institut fuer Plasmaphysik, Garching (Germany))

    1991-01-01

    Langmuir triple probes can provide simultaneous measurements of n[sub e], T[sub e] and V[sub pl] with good temporal and spatial resolution, and therefore are especially suited to detailed investigations of plasma turbulence in the scrape-off-layer. Unfortunately, the finite tip separation coupled with the fluctuating gradients prevents a simple interpretation of the results. We have developed a method using, essentially, two or more triple probes, which allows a good estimate of the three plasma parameters and their spatial derivatives at each point of time (assuming tip separation is much less than correlation length and dimensionless fluctuation levels are much less than unity). In particular, we can unambiguously measure the temperature fluctuations and the turbulent particle and heat flux. (author) 1 fig.

  15. Acoustic Measurements of an Uninstalled Spacecraft Cabin Ventilation Fan Prototype

    Koch, L. Danielle; Brown, Clifford A.; Shook, Tony D.; Winkel, James; Kolacz, John S.; Podboy, Devin M.; Loew, Raymond A.; Mirecki, Julius H.

    2012-01-01

    Sound pressure measurements were recorded for a prototype of a spacecraft cabin ventilation fan in a test in the NASA Glenn Acoustical Testing Laboratory. The axial fan is approximately 0.089 m (3.50 in.) in diameter and 0.223 m (9.00 in.) long and has nine rotor blades and eleven stator vanes. At design point of 12,000 rpm, the fan was predicted to produce a flow rate of 0.709 cu m/s (150 cfm) and a total pressure rise of 925 Pa (3.72 in. of water) at 12,000 rpm. While the fan was designed to be part of a ducted atmospheric revitalization system, no attempt was made to throttle the flow or simulate the installed configuration during this test. The fan was operated at six speeds from 6,000 to 13,500 rpm. A 13-microphone traversing array was used to collect sound pressure measurements along two horizontal planes parallel to the flow direction, two vertical planes upstream of the fan inlet and two vertical planes downstream of the fan exhaust. Measurements indicate that sound at blade passing frequency harmonics contribute significantly to the overall audible noise produced by the fan at free delivery conditions.

  16. A global study of hot flow anomalies using Cluster multi-spacecraft measurements

    G. Facskó

    2009-05-01

    Full Text Available Hot flow anomalies (HFAs are studied using observations of the magnetometer and the plasma instrument aboard the four Cluster spacecraft. We study several specific features of tangential discontinuities on the basis of Cluster measurements from the time periods of February–April 2003, December 2005–April 2006 and January–April 2007, when the separation distance of spacecraft was large. The previously discovered condition (Facskó et al., 2008 for forming HFAs is confirmed, i.e. that the solar wind speed and fast magnetosonic Mach number values are higher than average. Furthermore, this constraint is independent of the Schwartz et al. (2000’s condition for HFA formation. The existence of this new condition is confirmed by simultaneous ACE magnetic field and solar wind plasma observations at the L1 point, at 1.4 million km distance from the Earth. The temperature, particle density and pressure parameters observed at the time of HFA formation are also studied and compared to average values of the solar wind plasma. The size of the region affected by the HFA was estimated by using two different methods. We found that the size is mainly influenced by the magnetic shear and the angle between the discontinuity normal and the Sun-Earth direction. The size grows with the shear and (up to a certain point with the angle as well. After that point it starts decreasing. The results are compared with the outcome of recent hybrid simulations.

  17. Marginalized particle filter for spacecraft attitude estimation from vector measurements

    Yaqiu LIU; Xueyuan JIANG; Guangfu MA

    2007-01-01

    An algorithm based on the marginalized particle filters(MPF)is given in details in this paper to solve the spacecraft attitude estimation problem:attitude and gyro bias estimation using the biased gyro and vector observations.In this algorithm,by marginalizing out the state appearing linearly in the spacecraft model,the Kalman filter is associated with each particle in order to reduce the size of the state space and computational burden.The distribution of attitude vector is approximated by a set of particles and estimated using particle filter,while the estimation of gyro bias is obtained for each one of the attitude particles by applying the Kalman filter.The efficiency of this modified MPF estimator is verified through numerical simulation of a fully actuated rigid body.For comparison,unscented Kalman filter(UKF)is also used to gauge the performance of MPF.The results presented in this paper clearly demonstrate that the MPF is superior to UKF in coping with the nonlinear model.

  18. Spacecraft Trajectory Estimation Using a Sampled-Data Extended Kalman Filter with Range-Only Measurements

    Erwin, R. S; Bernstein, Dennis S

    2005-01-01

    .... In this paper we use a sampled-data extended Kalman Filter to estimate the trajectory or a target satellite when only range measurements are available from a constellation or orbiting spacecraft...

  19. Global Precipitation Measurement (GPM) Spacecraft Lithium Ion Battery Micro-Cycling Investigation

    Dakermanji, George; Lee, Leonine; Spitzer, Thomas

    2016-01-01

    The Global Precipitation Measurement (GPM) spacecraft was jointly developed by NASA and JAXA. It is a Low Earth Orbit (LEO) spacecraft launched on February 27, 2014. The power system is a Direct Energy Transfer (DET) system designed to support 1950 watts orbit average power. The batteries use SONY 18650HC cells and consist of three 8s by 84p batteries operated in parallel as a single battery. During instrument integration with the spacecraft, large current transients were observed in the battery. Investigation into the matter traced the cause to the Dual-Frequency Precipitation Radar (DPR) phased array radar which generates cyclical high rate current transients on the spacecraft power bus. The power system electronics interaction with these transients resulted in the current transients in the battery. An accelerated test program was developed to bound the effect, and to assess the impact to the mission.

  20. Combined spacecraft orbit and attitude control through extended Kalman filtering of magnetometer, gyro, and GPS measurements

    Tamer Mekky Ahmed Habib

    2014-06-01

    Full Text Available The main goal of this research is to establish spacecraft orbit and attitude control algorithms based on extended Kalman filter which provides estimates of spacecraft orbital and attitude states. The control and estimation algorithms must be capable of dealing with the spacecraft conditions during the detumbling and attitude acquisition modes of operation. These conditions are characterized by nonlinearities represented by large initial attitude angles, large initial angular velocities, large initial attitude estimation error, and large initial position estimation error. All of the developed estimation and control algorithms are suitable for application to the next Egyptian scientific satellite, EGYPTSAT-2. The parameters of the case-study spacecraft are similar but not identical to the former Egyptian satellite EGYPTSAT-1. This is done because the parameters of EGYPTSAT-2 satellite have not been consolidated yet. The sensors utilized are gyro, magnetometer, and GPS. Gyro and magnetometer are utilized to provide measurements for the estimates of spacecraft attitude state vector where as magnetometer and GPS are utilized to provide measurements for the estimates of spacecraft orbital state vector.

  1. Proposed Modifications to Engineering Design Guidelines Related to Resistivity Measurements and Spacecraft Charging

    Dennison, J. R.; Swaminathan, Prasanna; Jost, Randy; Brunson, Jerilyn; Green, Nelson; Frederickson, A. Robb

    2005-01-01

    A key parameter in modeling differential spacecraft charging is the resistivity of insulating materials. This determines how charge will accumulate and redistribute across the spacecraft, as well as the time scale for charge transport and dissipation. Existing spacecraft charging guidelines recommend use of tests and imported resistivity data from handbooks that are based principally upon ASTM methods that are more applicable to classical ground conditions and designed for problems associated with power loss through the dielectric, than for how long charge can be stored on an insulator. These data have been found to underestimate charging effects by one to four orders of magnitude for spacecraft charging applications. A review is presented of methods to measure the resistive of highly insulating materials, including the electrometer-resistance method, the electrometer-constant voltage method, the voltage rate-of-change method and the charge storage method. This is based on joint experimental studies conducted at NASA Jet Propulsion Laboratory and Utah State University to investigate the charge storage method and its relation to spacecraft charging. The different methods are found to be appropriate for different resistivity ranges and for different charging circumstances. A simple physics-based model of these methods allows separation of the polarization current and dark current components from long duration measurements of resistivity over day- to month-long time scales. Model parameters are directly related to the magnitude of charge transfer and storage and the rate of charge transport. The model largely explains the observed differences in resistivity found using the different methods and provides a framework for recommendations for the appropriate test method for spacecraft materials with different resistivities and applications. The proposed changes to the existing engineering guidelines are intended to provide design engineers more appropriate methods for

  2. Correcting PSP electron measurements for the effects of spacecraft electrostatic and magnetic fields

    McGinnis, D.; Halekas, J. S.; Larson, D. E.; Whittlesey, P. L.; Kasper, J. C.

    2017-12-01

    The near-Sun environment which the Parker Solar Probe will investigate presents a unique challenge for the measurement of thermal and suprathermal electrons. Over one orbital period, the ionizing photon flux and charged particle densities vary to such an extent that the spacecraft could charge to electrostatic potentials ranging from a few volts to tens of volts or more, and it may even develop negative electrostatic potentials near closest approach. In addition, significant permanent magnetic fields from spacecraft components will perturb thermal electron trajectories. Given these effects, electron distribution function (EDF) measurements made by the SWEAP/SPAN electron sensors will be significantly affected. It is thus important to try to understand the extent and nature of such effects, and to remediate them as much as possible. To this end, we have incorporated magnetic fields and a model electrostatic potential field into particle tracing simulations to predict particle trajectories through the near spacecraft environment. These simulations allow us to estimate how the solid angle elements measured by SPAN deflect and stretch in the presence of these fields and therefore how and to what extent EDF measurements will be distorted. In this work, we demonstrate how this technique can be used to produce a `dewarping' correction factor. Further, we show that this factor can correct synthetic datasets simulating the warped EDFs that the SPAN instruments are likely to measure over a wide range of spacecraft potentials and plasma Debye lengths.

  3. Laser-based Relative Navigation Using GPS Measurements for Spacecraft Formation Flying

    Lee, Kwangwon; Oh, Hyungjik; Park, Han-Earl; Park, Sang-Young; Park, Chandeok

    2015-12-01

    This study presents a precise relative navigation algorithm using both laser and Global Positioning System (GPS) measurements in real time. The measurement model of the navigation algorithm between two spacecraft is comprised of relative distances measured by laser instruments and single differences of GPS pseudo-range measurements in spherical coordinates. Based on the measurement model, the Extended Kalman Filter (EKF) is applied to smooth the pseudo-range measurements and to obtain the relative navigation solution. While the navigation algorithm using only laser measurements might become inaccurate because of the limited accuracy of spacecraft attitude estimation when the distance between spacecraft is rather large, the proposed approach is able to provide an accurate solution even in such cases by employing the smoothed GPS pseudo-range measurements. Numerical simulations demonstrate that the errors of the proposed algorithm are reduced by more than about 12% compared to those of an algorithm using only laser measurements, as the accuracy of angular measurements is greater than 0.001° at relative distances greater than 30 km.

  4. Simultaneous Measurements of Substorm-Related Electron Energization in the Ionosphere and the Plasma Sheet

    Sivadas, N.; Semeter, J.; Nishimura, Y.; Kero, A.

    2017-10-01

    On 26 March 2008, simultaneous measurements of a large substorm were made using the Poker Flat Incoherent Scatter Radar, Time History of Events and Macroscale Interactions during Substorm (THEMIS) spacecraft, and all sky cameras. After the onset, electron precipitation reached energies ≳100 keV leading to intense D region ionization. Identifying the source of energetic precipitation has been a challenge because of lack of quantitative and magnetically conjugate measurements of loss cone electrons. In this study, we use the maximum entropy inversion technique to invert altitude profiles of ionization measured by the radar to estimate the loss cone energy spectra of primary electrons. By comparing them with magnetically conjugate measurements from THEMIS-D spacecraft in the nightside plasma sheet, we constrain the source location and acceleration mechanism of precipitating electrons of different energy ranges. Our analysis suggests that the observed electrons ≳100 keV are a result of pitch angle scattering of electrons originating from or tailward of the inner plasma sheet at 9RE, possibly through interaction with electromagnetic ion cyclotron waves. The electrons of energy 10-100 keV are produced by pitch angle scattering due to a potential drop of ≲10 kV in the auroral acceleration region (AAR) as well as wave-particle interactions in and tailward of the AAR. This work demonstrates the utility of magnetically conjugate ground- and space-based measurements in constraining the source of energetic electron precipitation. Unlike in situ spacecraft measurements, ground-based incoherent scatter radars combined with an appropriate inversion technique can be used to provide remote and continuous-time estimates of loss cone electrons in the plasma sheet.

  5. Vega-1 and Vega-2: vertical profiles of wind velocity according to Doppler measurements data at landing spacecrafts

    Kerzhanovich, V.V.; Antsibor, N.M.; Bakit'ko, R.V.

    1987-01-01

    Results of the measurements of the Venus atmosphere vertical motion using the ''Vega'' landing spacecrafts are presented. Signal emitted by the landing spacecraft transmitter was received by flying apparatus and retranslated to the Earth. The difference between the measured frequency of the retranslated signal and reference one (Doppler's shift) permitted to determine the velocity of the landing spacecraft with the accuracy of 2 cm/s with the pitch of 1 s

  6. Electron precipitation burst in the nighttime slot region measured simultaneously from two satellites

    Imhof, W.L.; Voss, H.D.; Mobilla, J.; Gaines, E.E.; Evans, D.S.

    1987-01-01

    Based on data acquired in 1982 with the Stimulated Emission of Energetic Particles payload on the low-altitude (170--280 km) S81-1 spacecraft and the Space Environment Monitor instrumentation on the NOAA 6 satellite (800--830 km), a study has been made of short-duration nighttime electron precipitation bursts at L = 2.0--35. From 54 passes of each satellite across the slot region simultaneously in time, 21 bursts were observed on the NOAA 6 spacecraft, and 76 on the S81-1 satellite. Five events, probably associated with lightning, were observed simultaneously from the two spacecraft within 1.2 s, providing a measure of the spatial extent of the bursts. This limited sample indicates that the intensity of precipitation events falls off with width in longitude and L shell but individual events extend as much as 5 0 in invariant latitude and 43 0 in longitude. The number of events above a given flux observed in each satellite was found to be approximately inversely proportional to the flux. The time average energy input to the atmosphere over the longitude range 180 0 E to 360 0 E at a local time of 2230 directly from short-duration bursts spanning a wide range of intensity enhancements was estimated to be about 6 x 10/sup -6/ ergs/cm 2 s in the northern hemisphere and about 1.5 x 10/sup -5/ ergs/cm 2 s in the southern hemisphere. In the south, this energy precipitation rate is lower than that from electrons in the drift loss cone by about 2 orders of magnitude. However, on the basis of these data alone we cannot discount weak bursts from being a major contributor to populating the drift loss cone with electrons which ultimately precipitate into the atmosphere. copyrightAmerican Geophysical Union 1987

  7. A multichannel analyzer computer system for simultaneously measuring 64 spectra

    Jin Yuheng; Wan Yuqing; Zhang Jiahong; Li Li; Chen Guozhu

    2000-01-01

    The author introduces a multichannel analyzer computer system for simultaneously measuring 64 spectra with 64 coded independent inputs. The system is developed for a double chopper neutron scattering time-of-flight spectrometer. The system structure, coding method, operating principle and performances are presented. The system can also be used for other nuclear physics experiments which need multichannel analyzer with independent coded inputs

  8. The Global Precipitation Measurement (GPM) Spacecraft Power System Design and Orbital Performance

    Dakermanji, George; Burns, Michael; Lee, Leonine; Lyons, John; Kim, David; Spitzer, Thomas; Kercheval, Bradford

    2016-01-01

    The Global Precipitation Measurement (GPM) spacecraft was jointly developed by National Aeronautics and Space Administration (NASA) and Japan Aerospace Exploration Agency (JAXA). It is a Low Earth Orbit (LEO) spacecraft launched on February 27, 2014. The spacecraft is in a circular 400 Km altitude, 65 degrees inclination nadir pointing orbit with a three year basic mission life. The solar array consists of two sun tracking wings with cable wraps. The panels are populated with triple junction cells of nominal 29.5% efficiency. One axis is canted by 52 degrees to provide power to the spacecraft at high beta angles. The power system is a Direct Energy Transfer (DET) system designed to support 1950 Watts orbit average power. The batteries use SONY 18650HC cells and consist of three 8s x 84p batteries operated in parallel as a single battery. The paper describes the power system design details, its performance to date and the lithium ion battery model that was developed for use in the energy balance analysis and is being used to predict the on-orbit health of the battery.

  9. Simultaneous measurements of transport and poroelastic properties of rocks.

    Hasanov, Azar K; Prasad, Manika; Batzle, Michael L

    2017-12-01

    A novel laboratory apparatus has been developed for simultaneous measurements of transport and poroelastic rock properties. These transport and poroelastic properties at reservoir pressure and temperature conditions are required inputs for various geoscience applications, such as reservoir simulation, basin modeling, or modeling of pore pressure generation. Traditionally, the transport and poroelastic properties are measured separately using, for example, the oscillating pore pressure method to measure hydraulic transport properties, static strain measurements for elastic properties, and pore volumometry for storage capacity. In addition to time, the separate set of measurements require either aliquot cores or subjecting the same core to multiple pressure tests. We modified the oscillating pore pressure method to build an experimental setup, capable of measuring permeability, storage capacity, and pseudo-bulk modulus of rocks simultaneously. We present here the test method, calibration measurements (capillary tube), and sample measurements (sandstone) of permeability and storage capacity at reservoir conditions. We establish that hydraulically measured storage capacities were overestimated by an order of magnitude when compared to elastically derived ones. Our concurrent measurement of elastic properties during the hydraulic experiment provides an independent constraint on storage capacity.

  10. Simultaneous optical and infrared polarization measurements of blazars

    Brindle, C.; Hough, J.H.; Bailey, J.A.; Axon, D.J.; Hyland, A.R.

    1986-01-01

    Measurements are presented of the polarization and flux of a sample of 28 blazars (21 BL Lacs and 7 OVV quasars) at optical and near-infrared wavelengths, with repeated observations for some objects. For 20 objects, these are the first reported polarization measurements in either the optical or infrared, and for most of them the first simultaneous measurements at these wavelengths. Out of a total of 42 observations a spectral dependence of polarization level and position angle is found, although not necessarily occurring together, on 15 occasions. (author)

  11. The effects of spacecraft charging and outgassing on the LADEE ion measurements

    Xie, Lianghai; Zhang, Xiaoping; Zheng, Yongchun; Guo, Dawei

    2017-05-01

    Abnormal ion signals can be usually seen in the Lunar Atmosphere and Dust Environment Explorer (LADEE) mission, including a suddenly enhanced current observed by the Lunar Dust Experiment (LDEX) near the sunlight-shadow boundary and an unexpected water ion measured by the neutral mass spectrometer (NMS), with their magnitudes insensitive to the convection electric field of solar wind but dependent on the SW density and the elapsed time of LADEE mission. By analyzing both the LDEX measurements and the NMS measurements, we find that the current enhancement can be caused by a negatively charged spacecraft in the shadow region while the significant water ions should be some artificial ions from spacecraft outgassing. The artificial water ions show a peak near 8:00 LT that may be related to a sunlight-controlled surface outgassing. In addition, the H2O flux can be enhanced near the end of the mission when the spacecraft has a lower altitude. It is found that the H2O enhancement is actually caused by an exosphere-contributed return flux, rather than a real water exosphere.

  12. Influence of the Ambient Electric Field on Measurements of the Actively Controlled Spacecraft Potential by MMS

    Torkar, K.; Nakamura, R.; Andriopoulou, M.; Giles, B. L.; Jeszenszky, H.; Khotyaintsev, Y. V.; Lindqvist, P.-A.; Torbert, R. B.

    2017-12-01

    Space missions with sophisticated plasma instrumentation such as Magnetospheric Multiscale, which employs four satellites to explore near-Earth space benefit from a low electric potential of the spacecraft, to improve the plasma measurements and therefore carry instruments to actively control the potential by means of ion beams. Without control, the potential varies in anticorrelation with plasma density and temperature to maintain an equilibrium between the plasma current and the one of photoelectrons produced at the surface and overcoming the potential barrier. A drawback of the controlled, almost constant potential is the difficulty to use it as convenient estimator for plasma density. This paper identifies a correlation between the spacecraft potential and the ambient electric field, both measured by double probes mounted at the end of wire booms, as the main responsible for artifacts in the potential data besides the known effect of the variable photoelectron production due to changing illumination of the surface. It is shown that the effect of density variations is too weak to explain the observed correlation with the electric field and that a correction of the artifacts can be achieved to enable the reconstruction of the uncontrolled potential and plasma density in turn. Two possible mechanisms are discussed: the asymmetry of the current-voltage characteristic determining the probe to plasma potential and the fact that a large equipotential structure embedded in an electric field results in asymmetries of both the emission and spatial distribution of photoelectrons, which results in an increase of the spacecraft potential.

  13. Simultaneous Rheoelectric Measurements of Strongly Conductive Complex Fluids

    Helal, Ahmed; Divoux, Thibaut; McKinley, Gareth H.

    2016-12-01

    We introduce an modular fixture designed for stress-controlled rheometers to perform simultaneous rheological and electrical measurements on strongly conductive complex fluids under shear. By means of a nontoxic liquid metal at room temperature, the electrical connection to the rotating shaft is completed with minimal additional mechanical friction, allowing for simultaneous stress measurements at values as low as 1 Pa. Motivated by applications such as flow batteries, we use the capabilities of this design to perform an extensive set of rheoelectric experiments on gels formulated from attractive carbon-black particles, at concentrations ranging from 4 to 15 wt %. First, experiments on gels at rest prepared with different shear histories show a robust power-law scaling between the elastic modulus G0' and the conductivity σ0 of the gels—i.e., G0'˜σ0α, with α =1.65 ±0.04 , regardless of the gel concentration. Second, we report conductivity measurements performed simultaneously with creep experiments. Changes in conductivity in the early stage of the experiments, also known as the Andrade-creep regime, reveal for the first time that plastic events take place in the bulk, while the shear rate γ ˙ decreases as a weak power law of time. The subsequent evolution of the conductivity and the shear rate allows us to propose a local yielding scenario that is in agreement with previous velocimetry measurements. Finally, to establish a set of benchmark data, we determine the constitutive rheological and electrical behavior of carbon-black gels. Corrections first introduced for mechanical measurements regarding shear inhomogeneity and wall slip are carefully extended to electrical measurements to accurately distinguish between bulk and surface contributions to the conductivity. As an illustrative example, we examine the constitutive rheoelectric properties of five different grades of carbon-black gels and we demonstrate the relevance of this rheoelectric apparatus as a

  14. Measuring multiple nano-textured areas simultaneously with imaging scatterometry

    Madsen, Jonas Skovlund; Hansen, Poul Erik; Bilenberg, Brian

    2017-01-01

    and areas with defects can be avoided. These advantages make imaging scatterometry a very effective and user-friendly characterization method and allow us to determine the homogeneity of a nano- Textured surface by performing pixel-wise analyses. In the analysis an inverse modelling approach is used, where...... measured diffraction efficiencies are compared to simulated diffraction efficiencies using a least-square fitting approach. We demonstrate an imaging scatterometry setup built into an optical microscope. The setup is capable of measuring multiple 2D gratings with pitches of 200 nm simultaneously...

  15. Simultaneous polarized neutron reflectometry and anisotropic magnetoresistance measurements.

    Demeter, J; Teichert, A; Kiefer, K; Wallacher, D; Ryll, H; Menéndez, E; Paramanik, D; Steitz, R; Van Haesendonck, C; Vantomme, A; Temst, K

    2011-03-01

    A novel experimental facility to carry out simultaneous polarized neutron reflectometry (PNR) and anisotropic magnetoresistance (AMR) measurements is presented. Performing both techniques at the same time increases their strength considerably. The proof of concept of this method is demonstrated on a CoO/Co bilayer exchange bias system. Although information on the same phenomena, such as the coercivity or the reversal mechanism, can be separately obtained from either of these techniques, the simultaneous application optimizes the consistency between both. In this way, possible differences in experimental conditions, such as applied magnetic field amplitude and orientation, sample temperature, magnetic history, etc., can be ruled out. Consequently, only differences in the fundamental sensitivities of the techniques can cause discrepancies in the interpretation between the two. The almost instantaneous information obtained from AMR can be used to reveal time-dependent effects during the PNR acquisition. Moreover, the information inferred from the AMR measurements can be used for optimizing the experimental conditions for the PNR measurements in a more efficient way than with the PNR measurements alone.

  16. Hand Monitor for Simultaneous Measurements of Alpha and Beta Contamination

    Andersson, I.Oe.; Braun, J.; Soederlund, B.

    1960-11-01

    An instrument is described which measures α and β contamination of the hands simultaneously. This has been achieved by using as detectors 8 flow counters paired in 4 units of two chambers, one unit for each side of the hand. The inner chamber of every unit (adjacent to the hands) delivers α-pulses, the outer chambers deliver β-pulses. When two finger contacts are pushed the detectors are closing around the hands and the measurement is started. Audible and visual warnings operate when the MPL is exceeded. Similar warnings ope.rate if hands are removed before the end of the counting period. The activity levels are logarithmically indicated on four pointer instruments, which are automatically zeroed when the next measurement is started. The instrument is now commercially available

  17. Hand Monitor for Simultaneous Measurements of Alpha and Beta Contamination

    Andersson, I Oe; Braun, J; Soederlund, B

    1960-11-15

    An instrument is described which measures {alpha} and {beta} contamination of the hands simultaneously. This has been achieved by using as detectors 8 flow counters paired in 4 units of two chambers, one unit for each side of the hand. The inner chamber of every unit (adjacent to the hands) delivers {alpha}-pulses, the outer chambers deliver {beta}-pulses. When two finger contacts are pushed the detectors are closing around the hands and the measurement is started. Audible and visual warnings operate when the MPL is exceeded. Similar warnings ope.rate if hands are removed before the end of the counting period. The activity levels are logarithmically indicated on four pointer instruments, which are automatically zeroed when the next measurement is started. The instrument is now commercially available.

  18. Simultaneous Authentication and Certification of Arms-Control Measurement Systems

    MacArthur, Duncan W.; Hauck, Danielle K.; Thron, Jonathan L.

    2012-01-01

    Most arms-control-treaty-monitoring scenarios involve a host party that makes a declaration regarding its nuclear material or items and a monitoring party that verifies that declaration. A verification system developed for such a use needs to be trusted by both parties. The first concern, primarily from the host party's point of view, is that any sensitive information that is collected must be protected without interfering in the efficient operation of the facility being monitored. This concern is addressed in what can be termed a 'certification' process. The second concern, of particular interest to the monitoring party, is that it must be possible to confirm the veracity of both the measurement system and the data produced by this measurement system. The monitoring party addresses these issues during an 'authentication' process. Addressing either one of these concerns independently is relatively straightforward. However, it is more difficult to simultaneously satisfy host party certification concerns and monitoring party authentication concerns. Typically, both parties will want the final access to the measurement system. We will describe an alternative approach that allows both parties to gain confidence simultaneously. This approach starts with (1) joint development of the measurement system followed by (2) host certification of several copies of the system and (3) random selection by the inspecting party of one copy to be use during the monitoring visit and one (or more) copy(s) to be returned to the inspecting party's facilities for (4) further hardware authentication; any remaining copies are stored under joint seal for use as spares. Following this process, the parties will jointly (5) perform functional testing on the selected measurement system and then (6) use this system during the monitoring visit. Steps (1) and (2) assure the host party as to the certification of whichever system is eventually used in the monitoring visit. Steps (1), (3), (4), and (5

  19. Pose Self-Measurement of Noncooperative Spacecraft Based on Solar Panel Triangle Structure

    Jingzhou Song

    2015-01-01

    Full Text Available Aiming at the recognition and location of noncooperative spacecraft, this paper presents a monocular vision pose measurement method based on solar triangle structure. First of all, an autonomous recognition algorithm of feature structure based on sliding window Hough transformation (SWHT and inscribed circle of a triangle is proposed, and the image coordinates of feature points on the triangle can be obtained relying on this algorithm, combined with the P4P algorithm and the structure of spacecraft, calculating the relative pose of target expressed by rotation and translation matrix. The whole algorithm can be loaded into the prewritten onboard program, which will get the autocomplete feature structure extraction and relative pose measurement without human intervention, and this method does not need to mount any markers on the target. Then compare the measured values with the accurate value of the laser tracker, so that a conclusion can be drawn that the maximum position error is lower than 5% and the rotation error is lower than 4%, which meets the requirements of noncooperative spacecraft’s pose measurement for observations, tracking, and docking in the final rendezvous phase.

  20. Multi-Spacecraft 3D differential emission measure tomography of the solar corona: STEREO results.

    Vásquez, A. M.; Frazin, R. A.

    We have recently developed a novel technique (called DEMT) for the em- pirical determination of the three-dimensional (3D) distribution of the so- lar corona differential emission measure through multi-spacecraft solar ro- tational tomography of extreme-ultaviolet (EUV) image time series (like those provided by EIT/SOHO and EUVI/STEREO). The technique allows, for the first time, to develop global 3D empirical maps of the coronal elec- tron temperature and density, in the height range 1.0 to 1.25 RS . DEMT constitutes a simple and powerful 3D analysis tool that obviates the need for structure specific modeling.

  1. Simultaneous Observations of Atmospheric Tides from Combined in Situ and Remote Observations at Mars from the MAVEN Spacecraft

    England, Scott L.; Liu, Guiping; Withers, Paul; Yigit, Erdal; Lo, Daniel; Jain, Sonal; Schneider, Nicholas M. (Inventor); Deighan, Justin; McClintock, William E.; Mahaffy, Paul R.; hide

    2016-01-01

    We report the observations of longitudinal variations in the Martian thermosphere associated with nonmigrating tides. Using the Neutral Gas Ion Mass Spectrometer (NGIMS) and the Imaging Ultraviolet Spectrograph (IUVS) on NASA's Mars Atmosphere and Volatile EvolutioN Mission (MAVEN) spacecraft, this study presents the first combined analysis of in situ and remote observations of atmospheric tides at Mars for overlapping volumes, local times, and overlapping date ranges. From the IUVS observations, we determine the altitude and latitudinal variation of the amplitude of the nonmigrating tidal signatures, which is combined with the NGIMS, providing information on the compositional impact of these waves. Both the observations of airglow from IUVS and the CO2 density observations from NGIMS reveal a strong wave number 2 signature in a fixed local time frame. The IUVS observations reveal a strong latitudinal dependence in the amplitude of the wave number 2 signature. Combining this with the accurate CO2 density observations from NGIMS, this would suggest that the CO2 density variation is as high as 27% at 0-10 deg latitude. The IUVS observations reveal little altitudinal dependence in the amplitude of the wave number 2 signature, varying by only 20% from 160 to 200 km. Observations of five different species with NGIMS show that the amplitude of the wave number 2 signature varies in proportion to the inverse of the species scale height, giving rise to variation in composition as a function of longitude. The analysis and discussion here provide a roadmap for further analysis as additional coincident data from these two instruments become available.

  2. Simultaneous Differential Polarimetric Measurements and Co-Polar Correlation Coefficient Measurement

    National Oceanic and Atmospheric Administration, Department of Commerce — A polarimetric Doppler weather radar system which allows measurement of linear orthogonal polarimetric variables without a switch by using simultaneous transmission...

  3. Prospects for Measuring Planetary Spin and Frame-Dragging in Spacecraft Timing Signals

    Schärer, Andreas; Bondarescu, Ruxandra [Department of Physics, University of Zurich, Zurich (Switzerland); Saha, Prasenjit [Department of Physics, University of Zurich, Zurich (Switzerland); Institute for Computational Science, University of Zurich, Zurich (Switzerland); Angélil, Raymond [Institute for Computational Science, University of Zurich, Zurich (Switzerland); Helled, Ravit [Institute for Computational Science, University of Zurich, Zurich (Switzerland); Department of Geosciences, Tel Aviv University, Tel Aviv (Israel); Jetzer, Philippe, E-mail: andreas.schaerer@physik.uzh.ch [Department of Physics, University of Zurich, Zurich (Switzerland)

    2017-09-05

    Satellite tracking involves sending electromagnetic signals to Earth. Both the orbit of the spacecraft and the electromagnetic signals themselves are affected by the curvature of spacetime. The arrival time of the pulses is compared to the ticks of local clocks to reconstruct the orbital path of the satellite to high accuracy, and implicitly measure general relativistic effects. In particular, Schwarzschild space curvature (static) and frame-dragging (stationary) due to the planet's spin affect the satellite's orbit. The dominant relativistic effect on the path of the signal photons is Shapiro delays due to static space curvature. We compute these effects for some current and proposed space missions, using a Hamiltonian formulation in four dimensions. For highly eccentric orbits, such as in the Juno mission and in the Cassini Grand Finale, the relativistic effects have a kick-like nature, which could be advantageous for detecting them if their signatures are properly modeled as functions of time. Frame-dragging appears, in principle, measurable by Juno and Cassini, though not by Galileo 5 and 6. Practical measurement would require disentangling frame-dragging from the Newtonian “foreground” such as the gravitational quadrupole which has an impact on both the spacecraft's orbit and the signal propagation. The foreground problem remains to be solved.

  4. Absolute orbit determination using line-of-sight vector measurements between formation flying spacecraft

    Ou, Yangwei; Zhang, Hongbo; Li, Bin

    2018-04-01

    The purpose of this paper is to show that absolute orbit determination can be achieved based on spacecraft formation. The relative position vectors expressed in the inertial frame are used as measurements. In this scheme, the optical camera is applied to measure the relative line-of-sight (LOS) angles, i.e., the azimuth and elevation. The LIDAR (Light radio Detecting And Ranging) or radar is used to measure the range and we assume that high-accuracy inertial attitude is available. When more deputies are included in the formation, the formation configuration is optimized from the perspective of the Fisher information theory. Considering the limitation on the field of view (FOV) of cameras, the visibility of spacecraft and the installation of cameras are investigated. In simulations, an extended Kalman filter (EKF) is used to estimate the position and velocity. The results show that the navigation accuracy can be enhanced by using more deputies and the installation of cameras significantly affects the navigation performance.

  5. Simultaneous measurement of the 37Ar and 39Ar activity

    Fisenko, A.V.

    1978-01-01

    A method for simultaneous measurement of 37 Ar and 39 Ar activities, based on the different radiation penetrabilities of these isotopes is described. Two versions are realized. In the first case, a two-section detector is used whose partition partially transmits 39 Ar β-radiation and fully absorbs 37 Ar Auger electrons. A mixture of 37 Ar and 39 Ar is introduced into an internal counter operating at anticoincidences with an external counter. In the second version, a scintillation detector is used as an external counter, while the 37 Ar- 39 Ar mixture is introduced into a gas counter with a thin cathode. The rated detection efficiency of 37 Ar radiation in both versions is 80%. When measurement duration is 500 h, the sensitivity is approximately 10 -14 and 6x10 -15 Ci for 39 Ar and 37 Ar respectively

  6. Space Flight Experiments to Measure Polymer Erosion and Contamination on Spacecraft

    Lillis, Maura C.; Youngstrom, Erica E.; Marx, Laura M.; Hammerstrom, Anne M.; Finefrock, Katherine D.; Youngstrom, Christiane A.; Kaminski, Carolyn; Fine, Elizabeth S.; Hunt, Patricia K.; deGroh, Kim K.

    2002-01-01

    Atomic oxygen erosion and silicone contamination are serious issues that could damage or destroy spacecraft components after orbiting for an extended period of time, such as on a space station or satellite. An experiment, the Polymer Erosion And Contamination Experiment (PEACE) will be conducted to study the effects of atomic oxygen (AO) erosion and silicone contamination, and it will provide information and contribute to a solution for these problems. PEACE will fly 43 different polymer materials that will be analyzed for AO erosion effects through two techniques: mass loss measurement and recession depth measurement. Pinhole cameras will provide information about the arrival direction of AO, and silicone contamination pinhole cameras will identify the source of silicone contamination on a spacecraft. All experimental hardware will be passively exposed to AO for up to two weeks in the actual space environment when it flies in the bay of a space shuttle. A second set of the PEACE Polymers is being exposed to the space environment for erosion yield determination as part of a second experiment, Materials International Space Station Experiment (MISSE). MISSE is a collaboration between several federal agencies and aerospace companies. During a space walk on August 16, 2001, MISSE was attached to the outside of the International Space Station (ISS) during an extravehicular activity (EVA), where it began its exposure to AO for approximately 1.5 years. The PEACE polymers, therefore, will be analyzed after both short-term and long-term AO exposures for a more complete study of AO effects.

  7. A comparison of field-aligned current signatures simultaneously observed by the MAGSAT and TIROS/NOAA spacecraft

    Kamide, Y.; Evans, D.S.; Cain, J.C.

    1984-01-01

    In order to examine the relative locations of auroral particle fluxes and field-aligned currents and to identify the main charge carriers of the field-aligned currents at auroral latitudes, nearly simultaneous data from the vector magnetometers on MAGSAT and of precipitating electrons with energies between 300 eV and 20 keV observed by TIROS-N and NOAA-6 are compared. For more than fifty cases, MAGSAT and TIROS and/or NOAA orbits occurred within two minutes (mostly within one minute) of each other in the dawn/dusk sectors, during the time the IMS meridian chains of ground magnetometers were operating from November, 1979 through January, 1980. The latitudinal boundaries of precipitating electrons are found to line up within 1 0 with those of the field-aligned current region. Major portions of the upward field-aligned currents in the poleward half of the evening-sector auroral oval and in the equatorward half of the morining-sector auroral oval appear to be carried by the precipitating keV electrons. (author)

  8. Simultaneous Authentication and Certification of Arms-Control Measurement Systems

    MacArthur, Duncan W. [Los Alamos National Laboratory; Hauck, Danielle K. [Los Alamos National Laboratory; Thron, Jonathan L. [Los Alamos National Laboratory

    2012-07-09

    Most arms-control-treaty-monitoring scenarios involve a host party that makes a declaration regarding its nuclear material or items and a monitoring party that verifies that declaration. A verification system developed for such a use needs to be trusted by both parties. The first concern, primarily from the host party's point of view, is that any sensitive information that is collected must be protected without interfering in the efficient operation of the facility being monitored. This concern is addressed in what can be termed a 'certification' process. The second concern, of particular interest to the monitoring party, is that it must be possible to confirm the veracity of both the measurement system and the data produced by this measurement system. The monitoring party addresses these issues during an 'authentication' process. Addressing either one of these concerns independently is relatively straightforward. However, it is more difficult to simultaneously satisfy host party certification concerns and monitoring party authentication concerns. Typically, both parties will want the final access to the measurement system. We will describe an alternative approach that allows both parties to gain confidence simultaneously. This approach starts with (1) joint development of the measurement system followed by (2) host certification of several copies of the system and (3) random selection by the inspecting party of one copy to be use during the monitoring visit and one (or more) copy(s) to be returned to the inspecting party's facilities for (4) further hardware authentication; any remaining copies are stored under joint seal for use as spares. Following this process, the parties will jointly (5) perform functional testing on the selected measurement system and then (6) use this system during the monitoring visit. Steps (1) and (2) assure the host party as to the certification of whichever system is eventually used in the monitoring visit

  9. Simultaneous drag and flow measurements of Olympic skeleton athletes

    Moon, Yae Eun; Digiulio, David; Peters, Steve; Wei, Timothy

    2009-11-01

    The Olympic sport of skeleton involves an athlete riding a small sled face first down a bobsled track at speeds up to 130 km/hr. In these races, the difference between gold and missing the medal stand altogether can be hundredths of a second per run. As such, reducing aerodynamic drag through proper body positioning is of first order importance. To better study the flow behavior and to improve the performance of the athletes, we constructed a static force balance system on a mock section of a bobsled track. Athlete and the sled are placed on the force balance system which is positioned at the exit of an open loop wind tunnel. Simultaneous drag force and DPIV velocity field measurements were made along with video recordings of body position to aid the athletes in determining their optimal aerodynamic body position.

  10. High-precision relative position and attitude measurement for on-orbit maintenance of spacecraft

    Zhu, Bing; Chen, Feng; Li, Dongdong; Wang, Ying

    2018-02-01

    In order to realize long-term on-orbit running of satellites, space stations, etc spacecrafts, in addition to the long life design of devices, The life of the spacecraft can also be extended by the on-orbit servicing and maintenance. Therefore, it is necessary to keep precise and detailed maintenance of key components. In this paper, a high-precision relative position and attitude measurement method used in the maintenance of key components is given. This method mainly considers the design of the passive cooperative marker, light-emitting device and high resolution camera in the presence of spatial stray light and noise. By using a series of algorithms, such as background elimination, feature extraction, position and attitude calculation, and so on, the high precision relative pose parameters as the input to the control system between key operation parts and maintenance equipment are obtained. The simulation results show that the algorithm is accurate and effective, satisfying the requirements of the precision operation technique.

  11. ASPI experiment: measurements of fields and waves on board the INTERBALL-1 spacecraft

    S. Klimov

    1997-05-01

    Full Text Available The plasma-wave experiment ASPI (analysis of spectra of plasma waves and instabilities on board the INTERBALL spacecraft is a combined wave diagnostics experiment. It performs measurements of the DC and AC magnetic field vector by flux-gate and search-coil sensors, the DC and AC electric field vector by Langmuir double probes and the plasma current by Langmuir split probe. Preliminary data analysis shows the low noise levels of the sensors and the compatibility of new data with the results of previous missions. During several months of in-orbit operation a rich collection of data was acquired, examples of which at the magnetopause and plasma sheet are presented in second part of the paper.

  12. Simultaneous Helmert transformations among multiple frames considering all relevant measurements

    Chang, Guobin; Lin, Peng; Bian, Hefang; Gao, Jingxiang

    2018-03-01

    Helmert or similarity models are widely employed to relate different coordinate frames. It is often encountered in practice to transform coordinates from more than one old frame into a new one. One may perform separate Helmert transformations for each old frame. However, although each transformation is locally optimal, this is not globally optimal. Transformations among three frames, namely one new and two old, are studied as an example. Simultaneous Helmert transformations among all frames are also studied. Least-squares estimation of the transformation parameters and the coordinates in the new frame of all stations involved is performed. A functional model for the transformations among multiple frames is developed. A realistic stochastic model is followed, in which not only non-common stations are taken into consideration, but also errors in all measurements are addressed. An algorithm of iterative linearizations and estimations is derived in detail. The proposed method is globally optimal, and, perhaps more importantly, it produces a unified network of the new frame providing coordinate estimates for all involved stations and the associated covariance matrix, with the latter being consistent with the true errors of the former. Simulations are conducted, and the results validate the superiority of the proposed combined method over separate approaches.

  13. Measurement of the inertial properties of the Helios F-1 spacecraft

    Gayman, W. H.

    1975-01-01

    A gravity pendulum method of measuring lateral moments of inertia of large structures with an error of less than 1% is outlined. The method is based on the fact that in a physical pendulum with a knife-edge support the distance from the axis of rotation to the system center of gravity determines the minimal period of oscillation and is equal to the system centroidal radius of gyration. The method is applied to results of a test procedure in which the Helios F-1 spacecraft was placed in a roll fixture with crossed flexure pivots as elastic constraints and system oscillation measurements were made with each of a set of added moment-of-inertia increments. Equations of motion are derived with allowance for the effect of the finite pivot radius and an error analysis is carried out to find the criterion for maximum accuracy in determining the square of the centroidal radius of gyration. The test procedure allows all measurements to be made with the specimen in upright position.

  14. Spacecraft Spin Test Facility

    Federal Laboratory Consortium — FUNCTION: Provides the capability to correct unbalances of spacecraft by using dynamic measurement techniques and static/coupled measurements to provide products of...

  15. Measurement of Charged Particle Interactions in Spacecraft and Planetary Habitat Shielding Materials

    Zeitlin, Cary J.; Heilbronn, Lawrence H.; Miller, Jack; Wilson, John W.; Singleterry, Robert C., Jr.

    2003-01-01

    observed (slight) energy dependence. An additional set of data will be presented from an analysis of shielding material performance in the 1 GeV/nucleon iron beam at the AGS. A wide variety of candidate materials for spacecraft construction, as well as elemental targets, have been placed in this beam and their effects on transmitted dose and dose equivalent measured. The results support a prediction by J. Wilson et al. that hydrogen-loaded materials give the greatest dose reduction per unit mass.

  16. Solar wind and magnetosphere plasma diagnostics by spacecraft electrostatic potential measurements

    A. Pedersen

    1995-02-01

    Full Text Available Several satellites (GEOS-1, GEOS-2, ISEE-1, Viking and CRRES carried electric field experiments on which probes were driven by a current from the satellite to be close to the plasma potential. The potential difference between an electric field probe and its spacecraft (with conductive surfaces can be used to determine the ambient electron density and/or electron flux with limited accuracy but with high time resolution, of the order of 10-100 ms. It is necessary for the development of this diagnostic method to understand the photoemission characteristics of probes and satellites. According to the electric field experiments on the above-mentioned satellites, all materials develop very similar photoemission properties when they are beyond the influence of atmospheric oxygen. The photoelectron yield steadily increases over the first few months in space and reaches values well above those measured on clean surfaces in the laboratory. The method can be used for solar radiation levels corresponding to distances from 0.4 to 5 AU from the Sun.

  17. Measurement system and model for simultaneously measuring 6DOF geometric errors.

    Zhao, Yuqiong; Zhang, Bin; Feng, Qibo

    2017-09-04

    A measurement system to simultaneously measure six degree-of-freedom (6DOF) geometric errors is proposed. The measurement method is based on a combination of mono-frequency laser interferometry and laser fiber collimation. A simpler and more integrated optical configuration is designed. To compensate for the measurement errors introduced by error crosstalk, element fabrication error, laser beam drift, and nonparallelism of two measurement beam, a unified measurement model, which can improve the measurement accuracy, is deduced and established using the ray-tracing method. A numerical simulation using the optical design software Zemax is conducted, and the results verify the correctness of the model. Several experiments are performed to demonstrate the feasibility and effectiveness of the proposed system and measurement model.

  18. Autocorrelation Study of Solar Wind Plasma and IMF Properties as Measured by the MAVEN Spacecraft

    Marquette, Melissa L.; Lillis, Robert J.; Halekas, J. S.; Luhmann, J. G.; Gruesbeck, J. R.; Espley, J. R.

    2018-04-01

    It has long been a goal of the heliophysics community to understand solar wind variability at heliocentric distances other than 1 AU, especially at ˜1.5 AU due to not only the steepening of solar wind stream interactions outside 1 AU but also the number of missions available there to measure it. In this study, we use 35 months of solar wind and interplanetary magnetic field (IMF) data taken at Mars by the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft to conduct an autocorrelation analysis of the solar wind speed, density, and dynamic pressure, which is derived from the speed and density, as well as the IMF strength and orientation. We found that the solar wind speed is coherent, that is, has an autocorrelation coefficient above 1/e, over roughly 56 hr, while the density and pressure are coherent over smaller intervals of roughly 25 and 20 hr, respectively, and that the IMF strength is coherent over time intervals of approximately 20 hr, while the cone and clock angles are considerably less steady but still somewhat coherent up to time lags of roughly 16 hr. We also found that when the speed, density, pressure, or IMF strength is higher than average, the solar wind or IMF becomes uncorrelated more quickly, while when they are below average, it tends to be steadier. This analysis allows us to make estimates of the values of solar wind plasma and IMF parameters when they are not directly measured and provide an approximation of the error associated with that estimate.

  19. New Platforms for Suborbital Astronomical Observations and In Situ Atmospheric Measurements: Spacecraft, Instruments, and Facilities

    Rodway, K.; DeForest, C. E.; Diller, J.; Vilas, F.; Sollitt, L. S.; Reyes, M. F.; Filo, A. S.; Anderson, E.

    2014-12-01

    Suborbital astronomical observations have over 50 years' history using NASA's sounding rockets and experimental space planes. The new commercial space industry is developing suborbital reusable launch vehicles (sRLV's) to provide low-cost, flexible, and frequent access to space at ~100 km altitude. In the case of XCOR Aerospace's Lynx spacecraft, the vehicle design and capabilities work well for hosting specially designed experiments that can be flown with a human-tended researcher or alone with the pilot on a customized mission. Some of the first-generation instruments and facilities that will conduct solar observations on dedicated Lynx science missions include the SwRI Solar Instrument Pointing Platform (SSIPP) and Atsa Suborbital Observatory, as well as KickSat sprites, which are picosatellites for in situ atmospheric and solar phenomena measurements. The SSIPP is a demonstration two-stage pointed solar observatory that operates inside the Lynx cockpit. The coarse pointing stage includes the pilot in the feedback loop, and the fine stage stabilizes the solar image to achieve arcsecond class pointing. SSIPP is a stepping-stone to future external instruments that can operate with larger apertures and shorter wavelengths in the solar atmosphere. The Planetary Science Institute's Atsa Suborbital Observatory combines the strengths of ground-based observatories and space-based observing to create a facility where a telescope is maintained and used interchangeably with either in-house facility instruments or user-provided instruments. The Atsa prototype is a proof of concept, hand-guided camera that mounts on the interior of the Lynx cockpit to test target acquisition and tracking for human-operated suborbital astronomy. KickSat sprites are mass-producible, one inch printed circuit boards (PCBs) populated by programmable off the shelf microprocessors and radios for real time data transmission. The sprite PCBs can integrate chip-based radiometers, magnetometers

  20. High-spatial-resolution electron density measurement by Langmuir probe for multi-point observations using tiny spacecraft

    Hoang, H.; Røed, K.; Bekkeng, T. A.; Trondsen, E.; Clausen, L. B. N.; Miloch, W. J.; Moen, J. I.

    2017-11-01

    A method for evaluating electron density using a single fixed-bias Langmuir probe is presented. The technique allows for high-spatio-temporal resolution electron density measurements, which can be effectively carried out by tiny spacecraft for multi-point observations in the ionosphere. The results are compared with the multi-needle Langmuir probe system, which is a scientific instrument developed at the University of Oslo comprising four fixed-bias cylindrical probes that allow small-scale plasma density structures to be characterized in the ionosphere. The technique proposed in this paper can comply with the requirements of future small-sized spacecraft, where the cost-effectiveness, limited space available on the craft, low power consumption and capacity for data-links need to be addressed. The first experimental results in both the plasma laboratory and space confirm the efficiency of the new approach. Moreover, detailed analyses on two challenging issues when deploying the DC Langmuir probe on a tiny spacecraft, which are the limited conductive area of the spacecraft and probe surface contamination, are presented in the paper. It is demonstrated that the limited conductive area, depending on applications, can either be of no concern for the experiment or can be resolved by mitigation methods. Surface contamination has a small impact on the performance of the developed probe.

  1. Simultaneous Multiplexed Measurement of RNA and Proteins in Single Cells

    Spyros Darmanis

    2016-01-01

    Full Text Available Significant advances have been made in methods to analyze genomes and transcriptomes of single cells, but to fully define cell states, proteins must also be accessed as central actors defining a cell’s phenotype. Methods currently used to analyze endogenous protein expression in single cells are limited in specificity, throughput, or multiplex capability. Here, we present an approach to simultaneously and specifically interrogate large sets of protein and RNA targets in lysates from individual cells, enabling investigations of cell functions and responses. We applied our method to investigate the effects of BMP4, an experimental therapeutic agent, on early-passage glioblastoma cell cultures. We uncovered significant heterogeneity in responses to treatment at levels of RNA and protein, with a subset of cells reacting in a distinct manner to BMP4. Moreover, we found overall poor correlation between protein and RNA at the level of single cells, with proteins more accurately defining responses to treatment.

  2. Simultaneous Multiplexed Measurement of RNA and Proteins in Single Cells.

    Darmanis, Spyros; Gallant, Caroline Julie; Marinescu, Voichita Dana; Niklasson, Mia; Segerman, Anna; Flamourakis, Georgios; Fredriksson, Simon; Assarsson, Erika; Lundberg, Martin; Nelander, Sven; Westermark, Bengt; Landegren, Ulf

    2016-01-12

    Significant advances have been made in methods to analyze genomes and transcriptomes of single cells, but to fully define cell states, proteins must also be accessed as central actors defining a cell's phenotype. Methods currently used to analyze endogenous protein expression in single cells are limited in specificity, throughput, or multiplex capability. Here, we present an approach to simultaneously and specifically interrogate large sets of protein and RNA targets in lysates from individual cells, enabling investigations of cell functions and responses. We applied our method to investigate the effects of BMP4, an experimental therapeutic agent, on early-passage glioblastoma cell cultures. We uncovered significant heterogeneity in responses to treatment at levels of RNA and protein, with a subset of cells reacting in a distinct manner to BMP4. Moreover, we found overall poor correlation between protein and RNA at the level of single cells, with proteins more accurately defining responses to treatment. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  3. Uncertainty relation and simultaneous measurements in quantum theory

    Busch, P.

    1982-01-01

    In this thesis the question for the interpretation of the uncertainty relation is picked up, and a program for the justification of its individualistic interpretation is formulated. By means of quantum mechanical models for the position and momentum measurement a justification of the interpretaton has been tried by reconstruction of the origin of the uncertainties from the conditions of the measuring devices and the determination of the relation of the measured results to the object. By means of a model of the common measurement it could be shown how the uncertainty relation results from the not eliminable mutual disturbance of the devices and the uncertainty relation for the measuring system. So finally the commutation relation is conclusive. For the illustration the split experiment is discussed, first according to Heisenberg with fixed split, then for the quantum mechanical, movable split (Bohr-Einstein). (orig./HSI) [de

  4. Simultaneous integral measurement of electron energy and charge albedoes

    Lockwood, G.J.; Miller, G.H.; Halbleib, J.A. Sr.

    Results of a series of experiments in which backscattered energy has been determined from precise energy deposition measurements using an improved technique are presented. The fraction of the energy backscattered for electrons incident on Be, Ti, Mo, and Ta is determined as a function of energy and angle of incidence. The improved technique for the absolute measurement of energy deposition using calorimeters involves square-wave (on-off) modulation of the beam. Uncertainties in the measured backscattered energy are 1 to 6 percent, except for Be at normal incidence where they must agree by definition. Experiment and theory agree quite well for Mo and Be at 60 0 . The measured data for Ta and Ti are clearly higher than the calculated results, which is not completely understood. (U.S.)

  5. Optimal Measurements for Simultaneous Quantum Estimation of Multiple Phases.

    Pezzè, Luca; Ciampini, Mario A; Spagnolo, Nicolò; Humphreys, Peter C; Datta, Animesh; Walmsley, Ian A; Barbieri, Marco; Sciarrino, Fabio; Smerzi, Augusto

    2017-09-29

    A quantum theory of multiphase estimation is crucial for quantum-enhanced sensing and imaging and may link quantum metrology to more complex quantum computation and communication protocols. In this Letter, we tackle one of the key difficulties of multiphase estimation: obtaining a measurement which saturates the fundamental sensitivity bounds. We derive necessary and sufficient conditions for projective measurements acting on pure states to saturate the ultimate theoretical bound on precision given by the quantum Fisher information matrix. We apply our theory to the specific example of interferometric phase estimation using photon number measurements, a convenient choice in the laboratory. Our results thus introduce concepts and methods relevant to the future theoretical and experimental development of multiparameter estimation.

  6. Apparatus for simultaneously measuring electrical conductivity and oxygen fugacity

    Netherton, R.; Duba, A.

    1978-01-31

    Electrical conductivity studies of silicates are useful in determining temperature vs depth in the earth. Realistic laboratory measurements of conduction mechanisms require that exact determinations of oxygen fugacity (fo{sub 2}) be made in the experimental environment. An apparatus is described that monitors system fo{sub 2} with a calcia-doped zirconia-oxygen cell while measuring electrical conductivity of iron-bearing silicates at high temperature (greater than 1000 K). The fo{sub 2} calculated thermodynamically from CO/CO{sub 2} mixing ratios agreed well with measurements made with the zirconia cell at 1473 K, except for fo{sub 2} greater than 10{sup -4} Pa, where, on a log{sub 10} scale, mixing-ratio errors were as large as +- 0.2. These errors are attributed to oxygen contamination in the CO{sub 2} and to mobile carbon deposits that formed in the apparatus.

  7. Optimal Measurements for Simultaneous Quantum Estimation of Multiple Phases

    Pezzè, Luca; Ciampini, Mario A.; Spagnolo, Nicolò; Humphreys, Peter C.; Datta, Animesh; Walmsley, Ian A.; Barbieri, Marco; Sciarrino, Fabio; Smerzi, Augusto

    2017-09-01

    A quantum theory of multiphase estimation is crucial for quantum-enhanced sensing and imaging and may link quantum metrology to more complex quantum computation and communication protocols. In this Letter, we tackle one of the key difficulties of multiphase estimation: obtaining a measurement which saturates the fundamental sensitivity bounds. We derive necessary and sufficient conditions for projective measurements acting on pure states to saturate the ultimate theoretical bound on precision given by the quantum Fisher information matrix. We apply our theory to the specific example of interferometric phase estimation using photon number measurements, a convenient choice in the laboratory. Our results thus introduce concepts and methods relevant to the future theoretical and experimental development of multiparameter estimation.

  8. Conception and preliminary evaluation of an optical fibre sensor for simultaneous measurement of pressure and temperature

    Bremer, K; Moss, B; Leen, G; Mueller, I; Lewis, E; Lochmann, S

    2009-01-01

    This paper presents a novel concept of simultaneously measuring pressure and temperature using a silica optical fibre extrinsic Fabry-Perot interferometric (EFPI) pressure sensor incorporating a fibre Bragg grating (FBG), which is constructed entirely from fused-silica. The novel device is used to simultaneously provide accurate pressure and temperature readings at the point of measurement. Furthermore, the FBG temperature measurement is used to eliminate the temperature cross-sensitivity of the EFPI pressure sensor.

  9. Simultaneous measurement of gravity acceleration and gravity gradient with an atom interferometer

    Sorrentino, F.; Lien, Y.-H.; Rosi, G.; Tino, G. M.; Bertoldi, A.; Bodart, Q.; Cacciapuoti, L.; Angelis, M. de; Prevedelli, M.

    2012-01-01

    We demonstrate a method to measure the gravitational acceleration with a dual cloud atom interferometer; the use of simultaneous atom interferometers reduces the effect of seismic noise on the gravity measurement. At the same time, the apparatus is capable of accurate measurements of the vertical gravity gradient. The ability to determine the gravity acceleration and gravity gradient simultaneously and with the same instrument opens interesting perspectives in geophysical applications.

  10. A flow cytometric assay for simultaneously measuring the ...

    This research objective was to exploit a novel method for measuring the proliferation, cytotoxicity of cytokine-induced killer (CIK) cells using carboxyfluorescein succinimidyl ester/proliferation index (CFSE/PI) and flow cytometric assay. As cells divide, CFSE is apportioned equally between the two daughter cells, leading to a ...

  11. Simultaneous measurement of triboelectrification and triboluminescence of crystalline materials

    Collins, Adam L.; Camara, Carlos G.; Van Cleve, Eli; Putterman, Seth J.

    2018-01-01

    Triboelectrification has been studied for over 2500 years, yet there is still a lack of fundamental understanding as to its origin. Given its utility in areas such as xerography, powder spray painting, and energy harvesting, many devices have been made to investigate triboelectrification at many length-scales, though few seek to additionally make use of triboluminescence: the emission of electromagnetic radiation immediately following a charge separation event. As devices for measuring triboelectrification became smaller and smaller, now measuring down to the atomic scale with atomic force microscope based designs, an appreciation for the collective and multi-scale nature of triboelectrification has perhaps abated. Consider that the energy required to move a unit charge is very large compared to a van der Waals interaction, yet peeling Scotch tape (whose adhesion is derived from van der Waals forces) can provide strong enough energy-focusing to generate X-ray emission. This paper presents a device to press approximately cm-sized materials together in a vacuum, with in situ alignment. Residual surface charge, force, and position and X-ray, visible light, and RF emission are measured for single crystal samples. Charge is therefore tracked throughout the charging and discharging processes, resulting in a more complete picture of triboelectrification, with controllable and measurable environmental influence. Macroscale charging is directly measured, whilst triboluminescence, originating in atomic-scale processes, probes the microscale. The apparatus was built with the goal of obtaining an ab initio-level explanation of triboelectrification for well-defined materials, at the micro- and macro-scale, which has eluded scientists for millennia.

  12. Simultaneous measurement of FDG-PET and NAT

    Musha, Toshimitsu; Matsuzaki, Haruyasu; Ishii, Kenji

    2011-01-01

    NAT (Neuronal Activity Topography), which has been developed by the Brain Functions Lab., Inc., displays on the standard brain surface locations of hyperactive and hyperactive neuronal activities, and this result is compared with locations of enhanced and suppressed glucose metabolism which were measured with fluorodeoxyglucose-positron emission tomography (FDG-PET) for three AD patients. Locations with enhanced glucose metabolism are approximately overlap areas with enhanced neuronal activities. (author)

  13. RheoDSC: A hyphenated technique for the simultaneous measurement of calorimetric and rheological evolutions

    Kiewiet, S; Janssens, V; Miltner, H. E; Van Assche, Gert; Van Puyvelde, Peter; Van Mele, B

    2008-01-01

    A newly developed hyphenated technique is presented combining an existing rheometer and differential scanning calorimeter into a single experimental setup. Through the development of a fixation accessory for differential scanning calorimeter (DSC) crucibles and a novel rotor, the simultaneous measurement is performed inside the well-controlled thermal environment of a Tzero (TM) DSC cell. Hence, the evolution of thermal and flow properties of a material can be simultaneously measured using st...

  14. Spacecraft Charge Monitor

    Goembel, L.

    2003-12-01

    We are currently developing a flight prototype Spacecraft Charge Monitor (SCM) with support from NASA's Small Business Innovation Research (SBIR) program. The device will use a recently proposed high energy-resolution electron spectroscopic technique to determine spacecraft floating potential. The inspiration for the technique came from data collected by the Atmosphere Explorer (AE) satellites in the 1970s. The data available from the AE satellites indicate that the SCM may be able to determine spacecraft floating potential to within 0.1 V under certain conditions. Such accurate measurement of spacecraft charge could be used to correct biases in space plasma measurements. The device may also be able to measure spacecraft floating potential in the solar wind and in orbit around other planets.

  15. Comparison of unilateral and simultaneous bilateral measurement of the globe position, using the Hertel exophthalmometer.

    Ameri, Hossein

    2012-02-03

    PURPOSE: To assess the effect of simultaneous measurement of the two eyes in Hertel exophthalmometry (i.e., when both readings are taken sequentially, without removing the instrument from the orbital rims) and to find out whether simultaneous measurement would influence the final reading of each eye. METHODS: In this prospective, comparative study, Hertel exophthalmometry was performed on 61 patients by two experienced observers. Only patients with no history of orbital disease were included. Three different measurements were performed on each patient by each observer. Initially, the right eye was measured separately, then the left eye was measured separately, and finally, both eyes were measured together. RESULTS: When the eyes were measured separately, in 30% of cases observers obtained equal readings in both eyes; in 47%, the difference between the two eyes was 1 mm; and in 23%, the difference was 2 mm or more. However, in simultaneous bilateral measurements, in 73% of cases, observers obtained equal readings in both eyes; in 24%, the difference between the two eyes was 1 mm; and only in 3% was the difference 2 mm or greater. Paired t tests showed that the mean difference between measurements of the two eyes was significantly smaller in simultaneous bilateral measurements (p <0.001). Interobserver variation was similar for measurements taken separately on each eye and for simultaneous bilateral measurements. CONCLUSIONS: When both eyes were measured simultaneously with the Hertel exophthalmometer, examiners were inclined to obtain similar readings in both eyes of patients with symmetrical-appearing eyes. The possible bias arising this way may reduce the reliability of Hertel exophthalmometer in relative exophthalmometry.

  16. Single uniform FBG for simultaneous measurement of liquid level and temperature

    Shu, Xuewen; Sugden, Kate; Bennion, Ian

    2010-01-01

    In this paper, we propose and demonstrate a novel scheme for simultaneous measurement of liquid level and temperature based on a simple uniform fiber Bragg grating (FBG) by monitoring both the short-wavelength-loss peaks and its Bragg resonance. The liquid level can be measured from the amplitude changes of the short-wavelength-loss peaks, while temperature can be measured from the wavelength shift of the Bragg resonance. Both theoretical simulation results and experimental results are presented. Such a scheme has some advantages including robustness, simplicity, flexibility in choosing sensitivity and simultaneous temperature measurement capability

  17. Simultaneous measurement of line electron density and Faraday rotation in the ISX-B tokamak

    Hutchinson, D.P.; Ma, C.H.; Staats, P.A.; Vander Sluis, K.L.

    1981-01-01

    A new diagnostic system utilizing a submillimetre-wave, phase-modulated polarimeter/interferometer has been used to simultaneously measure the time evolution of the line-averaged electron density and poloidal field-induced Faraday rotation in the ISX-B tokamak. The measurements, performed along four chords of the plasma column, have been correlated with poloidal field changes associated with a ramp in the Ohmic-heating current and by neutral-beam injection. These are the first simultaneous measurements of line electron density and Faraday rotation to be made along a chord of submillimetre laser beam in a tokamak plasma. (author)

  18. Spatial aliasing and distortion of energy distribution in the wave vector domain under multi-spacecraft measurements

    Y. Narita

    2009-08-01

    Full Text Available Aliasing is a general problem in the analysis of any measurements that make sampling at discrete points. Sampling in the spatial domain results in a periodic pattern of spectra in the wave vector domain. This effect is called spatial aliasing, and it is of particular importance for multi-spacecraft measurements in space. We first present the theoretical background of aliasing problems in the frequency domain and generalize it to the wave vector domain, and then present model calculations of spatial aliasing. The model calculations are performed for various configurations of the reciprocal vectors and energy spectra or distribution that are placed at different positions in the wave vector domain, and exhibit two effects on aliasing. One is weak aliasing, in which the true spectrum is distorted because of non-uniform aliasing contributions in the Brillouin zone. It is demonstrated that the energy distribution becomes elongated in the shortest reciprocal lattice vector direction in the wave vector domain. The other effect is strong aliasing, in which aliases have a significant contribution in the Brillouin zone and the energy distribution shows a false peak. These results give a caveat in multi-spacecraft data analysis in that spectral anisotropy obtained by a measurement has in general two origins: (1 natural and physical origins like anisotropy imposed by a mean magnetic field or a flow direction; and (2 aliasing effects that are imposed by the configuration of the measurement array (or the set of reciprocal vectors. This manuscript also discusses a possible method to estimate aliasing contributions in the Brillouin zone based on the measured spectrum and to correct the spectra for aliasing.

  19. Simultaneous compared with sequential blood pressure measurement results in smaller inter-arm blood pressure differences.

    van der Hoeven, Niels V; Lodestijn, Sophie; Nanninga, Stephanie; van Montfrans, Gert A; van den Born, Bert-Jan H

    2013-11-01

    There are currently few recommendations on how to assess inter-arm blood pressure (BP) differences. The authors compared simultaneous with sequential measurement on mean BP, inter-arm BP differences, and within-visit reproducibility in 240 patients stratified according to age (simultaneous and three sequential BP measurements were taken in each patient. Starting measurement type and starting arm for sequential measurements were randomized. Mean BP and inter-arm BP differences of the first pair and reproducibility of inter-arm BP differences of the first and second pair were compared between both methods. Mean systolic BP was 1.3±7.5 mm Hg lower during sequential compared with simultaneous measurement (Psequential measurement was on average higher than the second, suggesting an order effect. Absolute systolic inter-arm BP differences were smaller on simultaneous (6.2±6.7/3.3±3.5 mm Hg) compared with sequential BP measurement (7.8±7.3/4.6±5.6 mm Hg, PSimultaneous measurement of BP at both arms reduces order effects and results in smaller inter-arm BP differences, thereby potentially reducing unnecessary referral and diagnostic procedures. ©2013 Wiley Periodicals, Inc.

  20. Simultaneous measurement of hysteresis in capillary pressure and electric permittivity for multiphase flow through porous media

    Plug, W.J.; Slob, E.C.; Bruining, J.; Moreno Tirado, L.M.

    2007-01-01

    We present a tool that simultaneously measures the complex permittivity and the capillary pressure characteristics for multiphase flow. The sample holder is a parallel plate capacitor. A precision component analyzer is used to measure the impedance amplitude and phase angle as a function of

  1. Simultaneous measurements with 3D PIV and Acoustic Doppler Velocity Profiler

    Blanckaert, K.J.F.; McLelland, S.J.

    2009-01-01

    Simultaneous velocity measurements were taken using Particle Image Velocimetry (PIV) and an Acoustic Doppler Velocity Profiler (ADVP) in a sharp open-channel bend with an immobile gravel bed. The PIV measures 3D velocity vectors in a vertical plane (~40cm x 20cm) at a frequency of 7.5 Hz, whereas

  2. Conceptual scoring of receptive and expressive vocabulary measures in simultaneous and sequential bilingual children.

    Gross, Megan; Buac, Milijana; Kaushanskaya, Margarita

    2014-11-01

    The authors examined the effects of conceptual scoring on the performance of simultaneous and sequential bilinguals on standardized receptive and expressive vocabulary measures in English and Spanish. Participants included 40 English-speaking monolingual children, 39 simultaneous Spanish-English bilingual children, and 19 sequential bilingual children, ages 5-7. The children completed standardized receptive and expressive vocabulary measures in English and also in Spanish for those who were bilingual. After the standardized administration, bilingual children were given the opportunity to respond to missed items in their other language to obtain a conceptual score. Controlling for group differences in socioeconomic status (SES), both simultaneous and sequential bilingual children scored significantly below monolingual children on single-language measures of English receptive and expressive vocabulary. Conceptual scoring removed the significant difference between monolingual and simultaneous bilingual children in the receptive modality but not in the expressive modality; differences remained between monolingual and sequential bilingual children in both modalities. However, in both bilingual groups, conceptual scoring increased the proportion of children with vocabulary scores within the average range. Conceptual scoring does not fully ameliorate the bias inherent in single-language standardized vocabulary measures for bilingual children, but the procedures employed here may assist in ruling out vocabulary deficits, particularly in typically developing simultaneous bilingual children.

  3. Hyperspectral imaging for simultaneous measurements of two FRET biosensors in pancreatic β-cells.

    Elliott, Amicia D; Bedard, Noah; Ustione, Alessandro; Baird, Michelle A; Davidson, Michael W; Tkaczyk, Tomasz; Piston, David W

    2017-01-01

    Fluorescent protein (FP) biosensors based on Förster resonance energy transfer (FRET) are commonly used to study molecular processes in living cells. There are FP-FRET biosensors for many cellular molecules, but it remains difficult to perform simultaneous measurements of multiple biosensors. The overlapping emission spectra of the commonly used FPs, including CFP/YFP and GFP/RFP make dual FRET measurements challenging. In addition, a snapshot imaging modality is required for simultaneous imaging. The Image Mapping Spectrometer (IMS) is a snapshot hyperspectral imaging system that collects high resolution spectral data and can be used to overcome these challenges. We have previously demonstrated the IMS's capabilities for simultaneously imaging GFP and CFP/YFP-based biosensors in pancreatic β-cells. Here, we demonstrate a further capability of the IMS to image simultaneously two FRET biosensors with a single excitation band, one for cAMP and the other for Caspase-3. We use these measurements to measure simultaneously cAMP signaling and Caspase-3 activation in pancreatic β-cells during oxidative stress and hyperglycemia, which are essential components in the pathology of diabetes.

  4. Fiber Bragg grating sensor for simultaneous measurement of temperature and force using polymer open loop

    Huang, Yonglin; Zhang, Shiyan

    2014-07-01

    A fiber Bragg grating (FBG) sensor for simultaneous measurement of temperature and force is proposed and demonstrated. Where a part of uniform FBG (about one half length of an FBG) is attached on the polymer open loop, the FBG is divided into two parts which has an equal length. So the two parts can be regarded as two FBGs. Because of the difference of the Young's modulus and the thermal expansion coefficients for two parts of the FBG, the two Bragg reflection wavelengths are shift when the temperature and force are applied on the sensor. Simultaneous measurement of temperature and force is demonstrated experimentally. The experimental results show that the linear response to temperature and force are achieved. The value of applied temperature and force can be obtained from the two Bragg wavelength shift via the coefficient matrix. This study provides a simple and economical method to measure temperature and force simultaneously.

  5. Atom localization and center-of-mass wave-function determination via multiple simultaneous quadrature measurements

    Evers, Joerg; Qamar, Shahid; Zubairy, M. Suhail

    2007-01-01

    We discuss localization and center-of-mass wave-function measurement of a quantum particle using multiple simultaneous dispersive interactions of the particle with different standing-wave fields. In particular, we consider objects with an internal structure consisting of a single ground state and several excited states. The transitions between ground and the corresponding excited states are coupled to the light fields in the dispersive limit, thus giving rise to a phase shift of the light field during the interaction. We show that multiple simultaneous measurements allow both an increase in the measurement or localization precision in a single direction and the performance of multidimensional measurements or localization. Further, we show that multiple measurements may relax the experimental requirements for each individual measurement

  6. Measurement of elastic constants by simultaneously sensing longitudinal and shear waves as an overlapped signal

    Seo, Ho Geon; Song, Dong Gi; Jhang, Kyoung Young [Hanyang University, Seoul (Korea, Republic of)

    2016-04-15

    Measurement of elastic constants is crucial for engineering aspects of predicting the behavior of materials under load as well as structural health monitoring of material degradation. Ultrasonic velocity measurement for material properties has been broadly used as a nondestructive evaluation method for material characterization. In particular, pulse-echo method has been extensively utilized as it is not only simple but also effective when only one side of the inspected objects is accessible. However, the conventional technique in this approach measures longitudinal and shear waves individually to obtain their velocities. This produces a set of two data for each measurement. This paper proposes a simultaneous sensing system of longitudinal waves and shear waves for elastic constant measurement. The proposed system senses both these waves simultaneously as a single overlapped signal, which is then analyzed to calculate both the ultrasonic velocities for obtaining elastic constants. Therefore, this system requires just half the number of data to obtain elastic constants compared to the conventional individual measurement. The results of the proposed simultaneous measurement had smaller standard deviations than those in the individual measurement. These results validate that the proposed approach improves the efficiency and reliability of ultrasonic elastic constant measurement by reducing the complexity of the measurement system, its operating procedures, and the number of data.

  7. Measurement of elastic constants by simultaneously sensing longitudinal and shear waves as an overlapped signal

    Seo, Ho Geon; Song, Dong Gi; Jhang, Kyoung Young

    2016-01-01

    Measurement of elastic constants is crucial for engineering aspects of predicting the behavior of materials under load as well as structural health monitoring of material degradation. Ultrasonic velocity measurement for material properties has been broadly used as a nondestructive evaluation method for material characterization. In particular, pulse-echo method has been extensively utilized as it is not only simple but also effective when only one side of the inspected objects is accessible. However, the conventional technique in this approach measures longitudinal and shear waves individually to obtain their velocities. This produces a set of two data for each measurement. This paper proposes a simultaneous sensing system of longitudinal waves and shear waves for elastic constant measurement. The proposed system senses both these waves simultaneously as a single overlapped signal, which is then analyzed to calculate both the ultrasonic velocities for obtaining elastic constants. Therefore, this system requires just half the number of data to obtain elastic constants compared to the conventional individual measurement. The results of the proposed simultaneous measurement had smaller standard deviations than those in the individual measurement. These results validate that the proposed approach improves the efficiency and reliability of ultrasonic elastic constant measurement by reducing the complexity of the measurement system, its operating procedures, and the number of data

  8. A simple laser-based device for simultaneous microbial culture and absorbance measurement

    Abrevaya, X. C.; Cortón, E.; Areso, O.; Mauas, P. J. D.

    2013-07-01

    In this work we present a device specifically designed to study microbial growth with several applications related to environmental microbiology and other areas of research as astrobiology. The Automated Measuring and Cultivation device (AMC-d) enables semi-continuous absorbance measurements directly during cultivation. It can measure simultaneously up to 16 samples. Growth curves using low and fast growing microorganism were plotted, including Escherichia coli and Haloferax volcanii, a halophilic archaeon.

  9. A Simple Laser-Based Device for Simultaneous Microbial Culture and Absorbance Measurement

    Abrevaya, X. C.; Cortón, E.; Areso, O.; Mauas, P. J. D.

    2012-01-01

    In this work we present a device specifically designed to study microbial growth with several applications related to environmental microbiology and other areas of research as astrobiology. The Automated Measuring and Cultivation device (AMC-d) enables semi-continuous absorbance measurements directly during cultivation. It can measure simultaneously up to 16 samples. Growth curves using low and fast growing microorganism were plotted, including Escherichia coli and Haloferax volcanii, a halop...

  10. Simultaneous measurement of thyroxine and triiodothyronine in trout plasma using a solid-phase radioimmunoassay

    Omeljaniuk, R.J.; Cook, R.F.; Eales, J.G.

    1984-01-01

    A solid-phase radioimmunoassay (RIA) employing miniature G-25 Sephadex columns and a single isotope was evaluated for simultaneous measurement of T 3 (3,5,3'-triiodo-L-thyronine) and T 4 (L-thyroxine) in trout plasma. The method was judged reliable based on the characteristics of the standard curves, the high and consistent recoveries of T 3 (87.0 or 86.7 percent) and T 4 (103 or 98 percent) added either singly or in combination, low inter-( 3 and T 4 after plasma dilution, and acceptable correlations between hormone values obtained using either the simultaneous or single RIA methods (rsub(T3) = 0.89; rsub(T4) = 0.91). It is concluded that the simultaneous RIA with its savings in time, plasma volume, and reagents can be used to advantage to measure T 3 and T 4 in plasma of trout and presumably other vertebrates

  11. Simultaneous compared with sequential blood pressure measurement results in smaller inter-arm blood pressure differences

    van der Hoeven, Niels V.; Lodestijn, Sophie; Nanninga, Stephanie; van Montfrans, Gert A.; van den Born, Bert-Jan H.

    2013-01-01

    There are currently few recommendations on how to assess inter-arm blood pressure (BP) differences. The authors compared simultaneous with sequential measurement on mean BP, inter-arm BP differences, and within-visit reproducibility in 240 patients stratified according to age ( <50 or ≥60 years) and

  12. Extending the Simultaneous-Sequential Paradigm to Measure Perceptual Capacity for Features and Words

    Scharff, Alec; Palmer, John; Moore, Cathleen M.

    2011-01-01

    In perception, divided attention refers to conditions in which multiple stimuli are relevant to an observer. To measure the effect of divided attention in terms of perceptual capacity, we introduce an extension of the simultaneous-sequential paradigm. The extension makes predictions for fixed-capacity models as well as for unlimited-capacity…

  13. Using Spread Spectrum Transform for Fast and Robust Simultaneous Measurement in Active Sensors with Multiple Emitters

    Harbo, Anders La-Cour; Stoustrup, Jakob

    2002-01-01

    We present a signal processing algorithm for making robust and simultaneous measurements in an active sensor, which has one or more emitters and a receiver, and which employs some sort of signal processing hardware. Robustness means low sensitivity to time and frequency localized disturbances......-cost active sensors....

  14. Optical sensor technology for simultaneous measurement of particle speed and concentration of micro sized particles

    Clausen, Casper; Han, Anpan; Kristensen, Martin

    2013-01-01

    Experimental characterization of a sensor technology that can measure particle speed and concentration simultaneously in liquids and gases is presented here. The basic sensor principle is based on an optical element that shapes a light beam into well-defined fringes. The technology can be described...

  15. Simultaneous resonant x-ray diffraction measurement of polarization inversion and lattice strain in polycrystalline ferroelectrics

    Gorfman, S.; Simons, Hugh; Iamsasri, T.

    2016-01-01

    and strain in ferroelectrics is an ongoing challenge that so far has obscured its fundamental behaviour. By utilizing small intensity differences between Friedel pairs due to resonant scattering, we demonstrate a time-resolved X-ray diffraction technique for directly and simultaneously measuring both lattice...

  16. Simultaneous Measurements of Electrostatic and Magnetic Fluctuations in ASDEX Upgrade Edge Plasma

    Ionita, Codrina; Vianello, Nicola; Müller, H.W.

    2009-01-01

    In ASDEX Upgrade (AUG) electrostatic and magnetic fluctuations in the edge plasma region were measured simultaneously during ELMy H-mode (high confinement) plasmas and L-mode (low confinement) plasmas and during a transition between the two modes. A special probe was used containing six Langmuir...

  17. Hybrid MEFPI/FBG sensor for simultaneous measurement of strain and magnetic field

    Chen, Mao-qing; Zhao, Yong; Lv, Ri-qing; Xia, Feng

    2017-12-01

    A hybrid fiber-optic sensor consisting of a micro extrinsic Fabry-Perot Interferometer (MEFPI) and an etched fiber Bragg grating (FBG) is proposed, which can measure strain and magnetic field simultaneously. The etched FBG is sealed in a capillary with ferrofluids to detect the surrounding magnetic field. FBG with small diameter will be more sensitive to magnetic field is confirmed by simulation results. The MEFPI sensor that is prepared through welding a short section of hollow-core fiber (HCF) with single-mode fiber (SMF) is effective for strain detection. The experiment shows that strain and magnetic field can be successfully simultaneously detected based on hybrid MEFPI/FBG sensor. The sensitivities of the strain and magnetic field intensity are measured to be up to 1.41 pm/με and 5.11 pm/mT respectively. There is a negligible effect on each other, hence simultaneously measuring strain and magnetic field is feasible. It is anticipated that such easy preparation, compact and low-cost fiber-optic sensors for simultaneous measurement of strain and magnetic field could find important applications in practice.

  18. Simultaneous transmission of neutrons and gamma rays (NEUGAT) to measure fat in meat

    Bartle, C.M.

    1991-01-01

    A new method has been established for the measurement of fat in boneless meat based on the simultaneous transmission through the mixture of neutrons and γ-rays (NEUGAT Technique). The method is insensitive to the manner in which the fat is distributed in the meat, and to the thickness of the mixture. The method has been applied in a meat packing plant to fat measurement in boxes of boneless meat for export. (author)

  19. Comparison of 2D and 3D Vision Gaze with Simultaneous Measurements of Accommodation and Convergence

    Hori, Hiroki; Shiomi, Tomoki; Hasegawa, Satoshi; Takada, Hiroki; Omori, Masako; Matsuura, Yasuyuki; Ishio, Hiromu; Miyao, Masaru

    2014-01-01

    Accommodation and convergence were measured simultaneously while subjects viewed 2D and 3D images. The aim was to compare fixation distances between accommodation and convergence in young subjects while they viewed 2D and 3D images. Measurements were made three times, 40 seconds each, using 2D and 3D images. The result suggests that ocular functions during viewing of 3D images are very similar to those during natural viewing. Previously established and widely used theories, such that within a...

  20. Simultaneous determination of size and refractive index of red blood cells by light scattering measurements

    Ghosh, N.; Buddhiwant, P.; Uppal, A.; Majumder, S.K.; Patel, H.S.; Gupta, P.K.

    2006-01-01

    We present a fast and accurate approach for simultaneous determination of both the mean diameter and refractive index of a collection of red blood cells (RBCs). The approach uses the peak frequency of the power spectrum and the corresponding phase angle obtained by performing Fourier transform on the measured angular distribution of scattered light to determine these parameters. Results on the measurement of two important clinical parameters, the mean cell volume and mean cell hemoglobin concentration of a collection of RBCs, are presented

  1. Design of a device for simultaneous particle size and electrostatic charge measurement of inhalation drugs.

    Zhu, Kewu; Ng, Wai Kiong; Shen, Shoucang; Tan, Reginald B H; Heng, Paul W S

    2008-11-01

    To develop a device for simultaneous measurement of particle aerodynamic diameter and electrostatic charge of inhalation aerosols. An integrated system consisting of an add-on charge measurement device and a liquid impinger was developed to simultaneously determine particle aerodynamic diameter and electrostatic charge. The accuracy in charge measurement and fine particle fraction characterization of the new system was evaluated. The integrated system was then applied to analyze the electrostatic charges of a DPI formulation composed of salbutamol sulphate-Inhalac 230 dispersed using a Rotahaler. The charge measurement accuracy was comparable with the Faraday cage method, and incorporation of the charge measurement module had no effect on the performance of the liquid impinger. Salbutamol sulphate carried negative charges while the net charge of Inhalac 230 and un-dispersed salbutamol sulphate was found to be positive after being aerosolized from the inhaler. The instantaneous current signal was strong with small noise to signal ratio, and good reproducibility of charge to mass ratio was obtained for the DPI system investigated. A system for simultaneously measuring particle aerodynamic diameter and aerosol electrostatic charges has been developed, and the system provides a non-intrusive and reliable electrostatic charge characterization method for inhalation dosage forms.

  2. Simultaneous Rayleigh lidar and airglow measurements of middle atmospheric waves over low latitudes in India

    Taori, A.; Kamalakar, V.; Raghunath, K.; Rao, S. V. B.; Russell, J. M.

    2012-04-01

    We utilize simultaneous Rayleigh lidar and mesospheric OH and O2 airglow measurements to identify the dominant and propagating waves within 40-95 km altitude regions over a low latitude station Gadanki (13.8° N, 79.2 °E). It is found that waves with 0.4-0.6 h periodicity are common throughout the altitude range of 40-95 km with significant amplitudes. The ground based temperature measurements with lidar and airglow monitoring are found to compare well with SABER data. With simultaneous Rayleigh lidar (temperature) and mesospheric airglow (emission intensity and temperature) measurements, we estimate the amplitude growth and Krassovsky parameters to characterize the propagation and dissipation of these upward propagating waves.

  3. Simultaneous weak measurement of angular and spatial Goos-Hänchen and Imbert-Fedorov shifts

    Prajapati, Chandravati; Viswanathan, Nirmal K.

    2017-10-01

    We propose and demonstrate the weak measurement scheme to simultaneously measure the amplified angular and spatial contributions to the Goos-Hänchen (GH) and Imbert-Fedorov (IF) shifts, due to transmission through a glass plate. We have studied two cases of post-selection using a polarizer in the first case and a quarter-wave plate (QWP)-polarizer combination in the second case. The two cases are analyzed theoretically using Jones calculus of polarization formalism and the results are verified experimentally. In the first case of post-selection, the projection of the polarizer at +/- {{Δ }} away from the crossed position amplifies the angular GH and IF shifts, while in the second case of post-selection, the projection of QWP at +/- {{Δ }} and polarizer kept fixed measures the polarization ellipticity in the beam and thus amplifies the spatial shift along with the angular shift simultaneously, for {{Δ }}\\ll 1.

  4. A double Gerdien instrument for simultaneous bipolar air conductivity measurements on balloon platforms.

    Nicoll, K A; Harrison, R G

    2008-08-01

    A bipolar air conductivity instrument is described for use with a standard disposable meteorological radiosonde package. It is intended to provide electrical measurements at cloud boundaries, where the ratio of the bipolar air conductivities is affected by the presence of charged particles. The sensors are two identical Gerdien-type electrodes, which, through a voltage decay method, measure positive and negative air conductivities simultaneously. Voltage decay provides a thermally stable approach and a novel low current leakage electrometer switch is described which initiates the decay sequence. The radiosonde supplies power and telemetry, as well as measuring simultaneous meteorological data. A test flight using a tethered balloon determined positive (sigma(+)) and negative (sigma(-)) conductivities of sigma(+)=2.77+/-0.2 fS m(-1) and sigma(-)=2.82+/-0.2 fS m(-1), respectively, at 400 m aloft, with sigma(+)sigma(-)=0.98+/-0.04.

  5. Remotely sensed detection of sulfates on Mars: Laboratory measurements and spacecraft observations

    Cooper, Christopher David

    Visible, near-infrared, and mid-infrared spectroscopic measurements were made of physically realistic analogs of Martian soil containing silicates and sulfates. These measurements indicate that the physical structure of soil will control its spectroscopic properties. Orbital measurements from the Thermal Emission Spectrometer (TES) identified features similar to those seen in the laboratory mixtures. Maps were made of this sulfate-cemented soil which indicated that the presence of this material is not geographically controlled and hints at an origin for duricrust in atmosphere-surface interactions. Further confirmation comes from combining data from TES and the Imaging Spectrometer for Mars (ISM). This data shows a congruence between sulfate spectral features and water features. The likely form of the mappable sulfate in Martian soils is therefore a cemented mixture of hydrated sulfate mixed with silicates and oxides derived from crustal rocks. The combination of ISM and TES spectra in particular and spectra from multiple wavelength regimes in general also is an excellent technique for addressing other problems of interest regarding the geology of Mars. A number of topics including rock coatings in Syrtis Major and the nature of low albedo rock assemblages are addressed. Syrtis Major is found to behave differently in the thermal and near infrared, likely indicating that the spectral features are not related to simple coatings but perhaps processes like penetrative oxidation. TES Type I rocks are found to be high in pyroxene, but TES Type II rocks do not have a correlation with pyroxene. Spectral mixing trends indicate that dust and rock are the dominant two variables in surface composition on a large scale. A smaller mixing trend involves the physical breakup of sulfate-cemented soils into a loose, fine-grained, but still hydrated form. In all, this work provides strong evidence for the global identification and distribution of sulfate minerals in the Martian soil.

  6. Inconsistency between simultaneous blood pressure measurements in the arm, forearm, and leg in anesthetized children.

    Keidan, Ilan; Sidi, Avner; Ben-Menachem, Erez; Tene, Yael; Berkenstadt, Haim

    2014-02-01

    To determine the accuracy and precision of simultaneous noninvasive blood pressure (NIBP) measurement in the arm, forearm, and ankle in anesthetized children. Prospective, randomized study. University medical center. 101 ASA physical status 1 and 2 children (aged 1-8 yrs) scheduled for elective surgery with general anesthesia. Simultaneous NIBP measurements were recorded at the arm, forearm, and ankle at 5-minute intervals. The systolic blood pressure difference between the arm-forearm or the arm-ankle was within the ± 10% range in 63% and 29% of measurements, and within the ± 20% range in 85% and 67% of measurements, respectively. The diastolic blood pressure difference between the arm-forearm or the arm-ankle was within the ± 10% range in 42% and 44% and within the ± 20% range in 67% and 74% of measurements, respectively. In patients in whom the initial three NIBP measurements were within the ± 20% range between the forearm and arm, 86% of the subsequent measurements were also within that limit. Forearm and ankle NIBP measurements are unreliable and inconsistent with NIBP measured in the arm of anesthetized children. These alternative BP measurement sites are not reliable in accuracy (comparison with reference "gold" standard) and precision (reproducibility). Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Instantaneous local wave vector estimation from multi-spacecraft measurements using few spatial points

    T. D. Carozzi

    2004-07-01

    Full Text Available We introduce a technique to determine instantaneous local properties of waves based on discrete-time sampled, real-valued measurements from 4 or more spatial points. The technique is a generalisation to the spatial domain of the notion of instantaneous frequency used in signal processing. The quantities derived by our technique are closely related to those used in geometrical optics, namely the local wave vector and instantaneous phase velocity. Thus, this experimental technique complements ray-tracing. We provide example applications of the technique to electric field and potential data from the EFW instrument on Cluster. Cluster is the first space mission for which direct determination of the full 3-dimensional local wave vector is possible, as described here.

  8. Pose and Shape Reconstruction of a Noncooperative Spacecraft Using Camera and Range Measurements

    Renato Volpe

    2017-01-01

    Full Text Available Recent interest in on-orbit proximity operations has pushed towards the development of autonomous GNC strategies. In this sense, optical navigation enables a wide variety of possibilities as it can provide information not only about the kinematic state but also about the shape of the observed object. Various mission architectures have been either tested in space or studied on Earth. The present study deals with on-orbit relative pose and shape estimation with the use of a monocular camera and a distance sensor. The goal is to develop a filter which estimates an observed satellite’s relative position, velocity, attitude, and angular velocity, along with its shape, with the measurements obtained by a camera and a distance sensor mounted on board a chaser which is on a relative trajectory around the target. The filter’s efficiency is proved with a simulation on a virtual target object. The results of the simulation, even though relevant to a simplified scenario, show that the estimation process is successful and can be considered a promising strategy for a correct and safe docking maneuver.

  9. Dry fracture method for simultaneous measurement of in-situ stress state and material properties

    Serata, S.; Oka, S.; Kikuchi, S.

    1996-01-01

    Based on the dry fracture principle, a computerized borehole probe has been developed to measure stress state and material properties, simultaneously. The probe is designed to obtain a series of measurements in a continuing sequence along a borehole length, without any interruptive measures, such as resetting packers, taking indentation of borehole wall, overcoming, etc. The new dry fracture probe for the single fracture method is designed to overcome the difficulties posed by its ancestor which was based on the double fracture method. The accuracy of the single fracture method is confirmed by a close agreement with the theory, FE modeling and laboratory testing

  10. Atmospheric implications of simultaneous nighttime measurements of NO3 radicals and hono

    Pitts, J.N. Jr.; Biermann, H.W.; Atkinson, R.; Winer, A.M.

    1984-01-01

    Atmospheric concentrations of gaseous HONO and the NO 3 radical were measured simultaneously for the first time using long path differential optical absorption spectroscopy. Diurnal profiles are reported for two successive nights following days of moderate pollution at Riverside, California, together with concurrent measurements of NO 2 , O 3 and NO concentrations and an upper limit for HCHO levels. These measurements permit an examination of selected aspects of the nighttime atmospheric chemistry of HONO and the NO 3 radical and related species. Our data do not support a recently proposed homogeneous gas phase mechanism for HONO formation initiated by the reaction of the NO 3 radical with HCHO

  11. Simultaneous measurement of thermo-optic and thermal expansion coefficients with a single arm double interferometer.

    Domenegueti, Jose Francisco Miras; Andrade, Acacio A; Pilla, Viviane; Zilio, Sergio Carlos

    2017-01-09

    A low-cost single arm double interferometer was developed for the concurrent measurement of linear thermal expansion (α) and thermo-optic (dn/dT) coefficients of transparent samples with plane and parallel surfaces. Owing to its common-path optical arrangement, the device is compact and stable, and allows the simultaneous measurement of interferences arising from a low-finesse Fabry-Perot etalon and from a Mach-Zehnder-type interferometer. The method was demonstrated with measurements of solid (silica, BK7, SF6) and liquid (water, ethanol and acetone) samples.

  12. Simultaneous measurements of temperature and density in air flows using UV laser spectroscopy

    Fletcher, D. G.; Mckenzie, R. L.

    1991-01-01

    The simultaneous measurement of temperature and density using laser-induced fluorescence of oxygen in combination with Q-branch Raman scattering of nitrogen and oxygen is demonstrated in a low-speed air flow. The lowest density and temperature measured in the experiment correspond to the freestream values at Mach 5 in the Ames 3.5-Foot Hypersonic Wind Tunnel for stagnation conditions of 100 atm and 1000 K. The experimental results demonstrate the viability of the optical technique for measurements that support the study of compressible turbulence and the validation of numerical codes in supersonic and hypersonic wind tunnel flows.

  13. Simultaneously Measured Interarm Blood Pressure Difference and Stroke: An Individual Participants Data Meta-Analysis.

    Tomiyama, Hirofumi; Ohkuma, Toshiaki; Ninomiya, Toshiharu; Mastumoto, Chisa; Kario, Kazuomi; Hoshide, Satoshi; Kita, Yoshikuni; Inoguchi, Toyoshi; Maeda, Yasutaka; Kohara, Katsuhiko; Tabara, Yasuharu; Nakamura, Motoyuki; Ohkubo, Takayoshi; Watada, Hirotaka; Munakata, Masanori; Ohishi, Mitsuru; Ito, Norihisa; Nakamura, Michinari; Shoji, Tetsuo; Vlachopoulos, Charalambos; Yamashina, Akira

    2018-06-01

    We conducted individual participant data meta-analysis to examine the validity of interarm blood pressure difference in simultaneous measurement as a marker to identify subjects with ankle-brachial pressure index blood pressure difference >5 mm Hg as being associated with a significant odds ratio for the presence of ankle-brachial pressure index blood pressure difference >15 mm Hg was associated with a significant Cox stratified adjusted hazard ratio for subsequent stroke (hazard ratio, 2.42; 95% confidence interval, 1.27-4.60; P blood pressure differences, measured simultaneously in both arms, may be associated with vascular damage in the systemic arterial tree. These differences may be useful for identifying subjects with an ankle-brachial pressure index of blood pressure in both arms at the first visit. © 2018 American Heart Association, Inc.

  14. Up-taper-based Mach-Zehnder interferometer for temperature and strain simultaneous measurement.

    Kang, Zexin; Wen, Xiaodong; Li, Chao; Sun, Jiang; Wang, Jing; Jian, Shuisheng

    2014-04-20

    A novel all-fiber sensing configuration for simultaneous measurements of temperature and strain based on the up-taper Mach-Zehnder interferometer (MZI) with an in-line embedded fiber Bragg grating (FBG) is proposed and experimentally demonstrated. This configuration consists of two up-tapers fabricated by an excessive fusion splicing method and a short segment of inscribed FBG. Due to the different responses of the up-taper MZI and the FBG to the uniform variation of temperature and strain, the simultaneous measurement for these two variables could be achieved by real-time monitoring the transmission spectrum. For 0.01 nm wavelength resolution, a resolution of 0.311°C in temperature can be achieved, and the average strain resolution is 10.07 με.

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

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

    2014-08-07

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

  16. Implantable optogenetic device with CMOS IC technology for simultaneous optical measurement and stimulation

    Haruta, Makito; Kamiyama, Naoya; Nakajima, Shun; Motoyama, Mayumi; Kawahara, Mamiko; Ohta, Yasumi; Yamasaki, Atsushi; Takehara, Hiroaki; Noda, Toshihiko; Sasagawa, Kiyotaka; Ishikawa, Yasuyuki; Tokuda, Takashi; Hashimoto, Hitoshi; Ohta, Jun

    2017-05-01

    In this study, we have developed an implantable optogenetic device that can measure and stimulate neurons by an optical method based on CMOS IC technology. The device consist of a blue LED array for optically patterned stimulation, a CMOS image sensor for acquiring brain surface image, and eight green LEDs surrounding the CMOS image sensor for illumination. The blue LED array is placed on the CMOS image sensor. We implanted the device in the brain of a genetically modified mouse and successfully demonstrated the stimulation of neurons optically and simultaneously acquire intrinsic optical images of the brain surface using the image sensor. The integrated device can be used for simultaneously measuring and controlling neuronal activities in a living animal, which is important for the artificial control of brain functions.

  17. Simultaneous measurement of spectral sky radiance by a non-scanning multidirectional spectroradiometer (MUDIS)

    Riechelmann, Stefan; Schrempf, Michael; Seckmeyer, Gunther

    2013-01-01

    We present a novel non-scanning multidirectional spectroradiometer (MUDIS) measuring the spectral sky radiance as a function of zenith and azimuth angle with a high spectral and temporal resolution. The instrument is based on a hyperspectral imager and measures spectral sky radiance in the wavelength range of 250–600 nm at 113 different directions simultaneously. MUDIS has been intercalibrated with a sky scanning CCD spectroradiometer (SCCD). Sky radiance measurements have been performed with both instruments under cloudless and overcast sky. The spectral actinic irradiance derived from those measurements agrees within 8% for wavelengths higher than 320 nm. The bias between synchronous MUDIS and SCCD sky radiance measurements during cloudless and overcast sky is below 5% for 320 and 500 nm with a 1σ standard deviation of less than 10%. MUDIS enables us to perform more than 220 000 spectral sky radiance measurements instead of approximately 6000 SCCD spectral sky radiance measurements per day and to measure spatial variations of spectral sky radiance simultaneously. (paper)

  18. Simultaneous measurements of bulk moduli and particle dynamics in a sheared colloidal glass

    Massa, Michael V.; Eisenmann, Christoph; Kim, Chanjoong; Weitz, David A.

    2007-03-01

    We present a novel study of glassy colloidal systems, using a stress-controlled rheometer in conjunction with a confocal microscope. This experimental setup combines the measurement of bulk moduli, using conventional rheology, with the ability to track the motion of individual particles, through confocal microscopy techniques. We explore the response of the system to applied shear, by simultaneously monitoring the macroscopic relaxation and microscopic particle dynamics, under conditions from the quiescent glass to a shear-melted liquid.

  19. Simultaneous measurement of particle velocity and size based on gray difference and autocorrelation

    2010-01-01

    The gray of two images of a same particle taken by a digital camera with different exposure times is different too. Based on the gray difference of particle images in a double-exposed photo and autocorrelation processing of digital images,this paper proposes a method for measuring particle velocities and sizes simultaneously. This paper also introduces the theoretical foundation of this method,the process of particle imaging and image processing,and the simultaneous measurement of velocity and size of a low speed flow field with 35 μm and 75 μm standard particles. The graphical measurement results can really reflect the flow characteristics of the flow field. In addition,although the measured velocity and size histograms of these two kinds of standard particles are slightly wider than the theoretical ones,they are all still similar to the normal distribution,and the peak velocities and diameters of the histograms are consistent with the default values. Therefore,this measurement method is capable of providing moderate measurement accuracy,and it can be further developed for high-speed flow field measurements.

  20. A New Approach to Isolating External Magnetic Field Components in Spacecraft Measurements of the Earth's Magnetic Field Using Global Positioning System observables

    Raymond, C.; Hajj, G.

    1994-01-01

    We review the problem of separating components of the magnetic field arising from sources in the Earth's core and lithosphere, from those contributions arising external to the Earth, namely ionospheric and magnetospheric fields, in spacecraft measurements of the Earth's magnetic field.

  1. Measurement of the Top Quark Mass Simultaneously in Dilepton and Lepton + Jets Decay Channels

    Fedorko, Wojciech T. [Univ. of Chicago, IL (United States)

    2008-12-01

    The authors present the first measurement of the top quark mass using simultaneously data from two decay channels. They use a data sample of √s = 1.96 TeV collisions with integrated luminosity of 1.9 fb-1 collected by the CDF II detector. They select dilepton and lepton + jets channel decays of t$\\bar{t}$ pairs and reconstruct two observables in each topology. They use non-parametric techniques to derive probability density functions from simulated signal and background samples. The observables are the reconstructed top quark mass and the scalar sum of transverse energy of the event in the dilepton topology and the reconstructed top quark mass and the invariant mass of jets from the W boson decay in lepton + jets channel. They perform a simultaneous fit for the top quark mass and the jet energy scale which is constrained in situ by the hadronic W boson resonance from the lepton + jets channel. Using 144 dilepton candidate events and 332 lepton + jets candidate events they measure: Mtop = 171.9 ± 1.7 (stat. + JES) ± 1.1 (other sys.) GeV/c2 = 171.9 ± 2.0 GeV/c2. The measurement features a robust treatment of the systematic uncertainties, correlated between the two channels and develops techniques for a future top quark mass measurement simultaneously in all decay channels. Measurements of the W boson mass and the top quark mass provide a constraint on the mass of the yet unobserved Higgs boson. The Higgs boson mass implied by measurement presented here is higher than Higgs boson mass implied by previously published, most precise CDF measurements of the top quark mass in lepton + jets and dilepton channels separately.

  2. Mobile CARS - IRS Instrument for Simultaneous Spectroscopic Measurement of Multiple Properties in Gaseous Flows

    Bivolaru, Daniel; Lee, Joseph W.; Jones, Stephen B.; Tedder, Sarah A.; Danehy, Paul M.; Weikl, M. C.; Magnotti, G.; Cutler, Andrew D.

    2007-01-01

    This paper describes a measurement system based on the dual-pump coherent anti-Stokes Raman spectroscopy (CARS) and interferometric Rayleigh scattering (IRS) methods. The IRS measurement is performed simultaneously with the CARS measurement using a common green laser beam as a narrow-band light source. The mobile CARS-IRS instrument is designed for the use both in laboratories as well as in ground-based combustion test facilities. Furthermore, it is designed to be easily transported between laboratory and test facility. It performs single-point spatially and temporally resolved simultaneous measurements of temperature, species mole fraction of N2, O2, and H2, and two-components of velocity. A mobile laser system can be placed inside or outside the test facility, while a beam receiving and monitoring system is placed near the measurement location. Measurements in a laboratory small-scale Mach 1.6 H2-air combustion-heated supersonic jet were performed to test the capability of the system. Final setup and pretests of a larger scale reacting jet are ongoing at NASA Langley Research Center s Direct Connect Supersonic Combustor Test Facility (DCSCTF).

  3. Simultaneous measurements of helium and heavy nuclei fluxes in cosmic rays over Fort Churchill

    Bhatia, V.S.; Paruthi, S.; Kainth, G.S.

    1977-01-01

    We have made simultaneous measurements of fluxes of He an heavy nuclei (Z< or =10) in primary cosmic rays at three levels of solar activity. These nuclei have been studied in three nuclear emulsion stacks exposed over Fort Churchill, Canada, in 1963, 1964, and 1967. We had earlier reported our results on the heavy nuclei at the Hobart conference (Bhatia et al., 1971). Experimental results based on 1514 He nuclei tracks that were measured in these three stacks are presented in this paper. The experimentally obtained He and heavy nuclei differential energy spectra have been compared with the theoretically calculated near-earth spectra

  4. Simultaneous measurement of dynamic strain and temperature distribution using high birefringence PANDA fiber Bragg grating

    Zhu, Mengshi; Murayama, Hideaki

    2017-04-01

    New approach in simultaneous measurement of dynamic strain and temperature has been done by using a high birefringence PANDA fiber Bragg grating sensor. By this technique, we have succeeded in discriminating dynamic strain and temperature distribution at the sampling rate of 800 Hz and the spatial resolution of 1 mm. The dynamic distribution of strain and temperature were measured with the deviation of 5mm spatially. In addition, we have designed an experimental setup by which we can apply quantitative dynamic strain and temperature distribution to the fiber under testing without bounding it to a specimen.

  5. Analysis of simultaneous measurement of temperature and strain using different combinations of FBG

    Ashik T., J.; Kachare, Nitin; Kalyani bai, K.; Kumar, D. Sriram

    2017-06-01

    The Fiber Bragg Grating (FBG) can be used for measuring temperature and or strain. In this paper analysis of different combinations of FBG is made. Certain parameters of FBG are considered such as Bandwidth, Side lobes, Peak power, and Sensitivity. Simultaneous measurement of temperature and strain is made using two combinations of FBG. The setup is simulated using two software. Optigrating 4.2.2 is used for designing different types of gratings such as Uniform, Apodized, Tilted and Superstructure. After designing, these files are exported to Optisystem 12 to simulate the spectrum and to observe the parameters.

  6. Simultaneous measurement of group refractive index and thickness of optical samples using optical coherence tomography

    Cheng, Hsu-Chih; Liu, Yi-Cheng

    2010-01-01

    Optical coherence tomography (OCT), based on a Michelson interferometer and utilizing low coherence light as the optical source, is a novel technique for the noninvasive imaging of optical scattering media. A simple OCT scheme based on a 3x3 fiber coupler is presented for the simultaneous measurement of the refractive index and thickness of optical samples. The proposed system enables the refractive index and thickness to be determined without any prior knowledge of the sample parameters and is characterized by a simple and compact configuration, a straightforward measurement procedure, and a low cost. The feasibility of the proposed approach is demonstrated experimentally using BK7 and B270 optical glass samples.

  7. Simultaneous measurement of Aspartate, NAA, and NAAG using HERMES spectral editing at 3 Tesla.

    Chan, Kimberly L; Saleh, Muhammad G; Oeltzschner, Georg; Barker, Peter B; Edden, Richard A E

    2017-07-15

    It has previously been shown that the HERMES method ('Hadamard Encoding and Reconstruction of MEGA-Edited Spectroscopy') can be used to simultaneously edit pairs of metabolites (such as N-acetyl-aspartate (NAA) and N-acetyl aspartyl glutamate (NAAG), or glutathione and GABA). In this study, HERMES is extended for the simultaneous editing of three overlapping signals, and illustrated for the example of NAA, NAAG and Aspartate (Asp). Density-matrix simulations were performed in order to optimize the HERMES sequence. The method was tested in NAA and Asp phantoms, and applied to the centrum semiovale of the nine healthy control subjects that were scanned at 3T. Both simulations and phantom experiments showed similar metabolite multiplet patterns with good segregation of all three metabolites. In vivo measurements show consistent relative signal intensities and multiplet patterns with concentrations in agreement with literature values. Simulations indicate co-editing of glutathione, glutamine, and glutamate, but their signals do not significantly overlap with the detected aspartyl resonances. This study demonstrates that a four-step Hadamard-encoded editing scheme can be used to simultaneously edit three otherwise overlapping metabolites, and can measure NAA, NAAG, and Asp in vivo in the brain at 3T with minimal crosstalk. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Magnetic field `flyby' measurement using a smartphone's magnetometer and accelerometer simultaneously

    Monteiro, Martín; Stari, Cecilia; Cabeza, Cecilia; Marti, Arturo C.

    2017-12-01

    The spatial dependence of magnetic fields in simple configurations is a common topic in introductory electromagnetism lessons, both in high school and in university courses. In typical experiments, magnetic fields and distances are obtained taking point-by-point values using a Hall sensor and a ruler, respectively. Here, we show how to take advantage of the smartphone capabilities to get simultaneous measures with the built-in accelerometer and magnetometer and to obtain the spatial dependence of magnetic fields. We consider a simple setup consisting of a smartphone mounted on a track whose direction coincides with the axis of a coil. While the smartphone is moving on the track, both the magnetic field and the distance from the center of the coil (integrated numerically from the acceleration values) are simultaneously obtained. This methodology can easily be extended to more complicated setups.

  9. Simultaneously measured pupillary light reflex and heart rate variability in healthy children

    Daluwatte, C; Yao, G; Miles, J H

    2012-01-01

    We investigated the potential inter-relationship between two measures of autonomic nervous system: pupillary light reflex (PLR) and heart rate variability (HRV), in healthy children of 8–16 years old. PLR was measured at both dark- and light-adapted conditions with various stimulation intensities. Simultaneously measured HRV was obtained in five different PLR testing phases: before PLR test, light-adapted PLR test, dark adaptation, dark-adapted PLR test and after PLR test. The frequency domain HRV parameters measured during the PLR test were significantly different from those measured during rest. Both the regression analysis and factor analysis indicated that PLR and HRV parameters were not correlated, which suggests that they may provide complementary assessment of different aspects of the overall autonomic nervous system. (paper)

  10. Simultaneously measured pupillary light reflex and heart rate variability in healthy children

    Daluwatte, C; Yao, G [Department of Biological Engineering, University of Missouri, Columbia, MO 65211 (United States); Miles, J H, E-mail: YaoG@missouri.edu [Child Health and Thompson Center for Autism and Neurodevelopmental Disorders, University of Missouri, Columbia, MO 65211 (United States)

    2012-06-15

    We investigated the potential inter-relationship between two measures of autonomic nervous system: pupillary light reflex (PLR) and heart rate variability (HRV), in healthy children of 8–16 years old. PLR was measured at both dark- and light-adapted conditions with various stimulation intensities. Simultaneously measured HRV was obtained in five different PLR testing phases: before PLR test, light-adapted PLR test, dark adaptation, dark-adapted PLR test and after PLR test. The frequency domain HRV parameters measured during the PLR test were significantly different from those measured during rest. Both the regression analysis and factor analysis indicated that PLR and HRV parameters were not correlated, which suggests that they may provide complementary assessment of different aspects of the overall autonomic nervous system. (paper)

  11. Simultaneous Measurement of Multiple Mechanical Properties of Single Cells Using AFM by Indentation and Vibration.

    Zhang, Chuang; Shi, Jialin; Wang, Wenxue; Xi, Ning; Wang, Yuechao; Liu, Lianqing

    2017-12-01

    The mechanical properties of cells, which are the main characteristics determining their physical performance and physiological functions, have been actively studied in the fields of cytobiology and biomedical engineering and for the development of medicines. In this study, an indentation-vibration-based method is proposed to simultaneously measure the mechanical properties of cells in situ, including cellular mass (m), elasticity (k), and viscosity (c). The proposed measurement method is implemented based on the principle of forced vibration stimulated by simple harmonic force using an atomic force microscope (AFM) system integrated with a piezoelectric transducer as the substrate vibrator. The corresponding theoretical model containing the three mechanical properties is derived and used to perform simulations and calculations. Living and fixed human embryonic kidney 293 (HEK 293) cells were subjected to indentation and vibration to measure and compare their mechanical parameters and verify the proposed approach. The results that the fixed sample cells are more viscous and elastic than the living sample cells and the measured mechanical properties of cell are consistent within, but not outside of the central region of the cell, are in accordance with the previous studies. This work provides an approach to simultaneous measurement of the multiple mechanical properties of single cells using an integrated AFM system based on the principle force vibration and thickness-corrected Hertz model. This study should contribute to progress in biomedical engineering, cytobiology, medicine, early diagnosis, specific therapy and cell-powered robots.

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

    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.

  13. A method enabling simultaneous pressure and temperature measurement using a single piezoresistive MEMS pressure sensor

    Frantlović, Miloš; Stanković, Srđan; Jokić, Ivana; Lazić, Žarko; Smiljanić, Milče; Obradov, Marko; Vukelić, Branko; Jakšić, Zoran

    2016-01-01

    In this paper we present a high-performance, simple and low-cost method for simultaneous measurement of pressure and temperature using a single piezoresistive MEMS pressure sensor. The proposed measurement method utilizes the parasitic temperature sensitivity of the sensing element for both pressure measurement correction and temperature measurement. A parametric mathematical model of the sensor was established and its parameters were calculated using the obtained characterization data. Based on the model, a real-time sensor correction for both pressure and temperature measurements was implemented in a target measurement system. The proposed method was verified experimentally on a group of typical industrial-grade piezoresistive sensors. The obtained results indicate that the method enables the pressure measurement performance to exceed that of typical digital industrial pressure transmitters, achieving at the same time the temperature measurement performance comparable to industrial-grade platinum resistance temperature sensors. The presented work is directly applicable in industrial instrumentation, where it can add temperature measurement capability to the existing pressure measurement instruments, requiring little or no additional hardware, and without adverse effects on pressure measurement performance. (paper)

  14. Simultaneous aerosol size distribution and turbidity measurements over St. Louis during METROMEX 1975

    Laulainen, N.S.; Alkezweeny, A.J.; Thorp, J.M.

    1978-01-01

    An experiment designed to measure aerosol size distributions and turbidity simultaneously over a metropolitan area is described. The particle volume size distributions measured in the city plume are found to be bimodal, with the total particle volume in the fine or submicron mode decreasing dramatically above the inversion. Aerosol extinction coefficients derived from sunphotometer optical depth measurements at four wavelengths are compared to those calculated from the measured size distributions using Mie theory with several different particle refractive indices. The accuracy of the experimental method for determining the aerosol extinction coefficient prevented any meaningful choice of the real part of particle refractive index between 1.5--1.6 and an imaginary part between 0 and -0.1i. Improvements to this type of experiment are discussed

  15. Simultaneous measurement of eye stiffness and contact area for living human eyes.

    Kurita, Yuichi; Iida, Yoshichika; Kaneko, Makoto; Mishima, Hiromu K; Katakura, Seiki; Kiuchi, Yoshiaki

    2007-01-01

    Goldmann applanation tonometry is commonly used for measuring IOP (IntraOcular Pressure) to diagnose glaucoma. However, the measured IOP by the applanation tonometry is valid only under the assumption that all the subjects have the same structural eye stiffness. Abnormal eye stiffness makes abnormal corneal deformation and thus the current applanation tonometer misestimates the IOP. This study challenges to measure the eye stiffness in vivo with a non-invasive approach for detecting the abnormal deformation. The deformation of the cornea and the contact area between the probe and the cornea are simultaneously captured by cameras during the experiment. Experimental results show that some subjects have different relationship among the force, the displacement and the contact area even with same IOP. The proposed eye stiffness measurement can help detecting the abnormal deformation and the eyes with misestimated IOP.

  16. Method for simultaneous measurement of borehole and formation neutron decay-times employing iterative fitting

    Schultz, W.E.

    1982-01-01

    A method is described of making in situ measurements of the thermal neutron decay time of earth formations in the vicinity of a wellbore. The borehole and earth formations in its vicinity are repetitively irradiated with pulsed fast neutrons and, during the intervals between pulses, capture gamma radiation is measured in at least four, non-overlapping, contiguous time intervals. A background radiation measurement is made between successive pulses and used to correct count-rates representative of thermal neutron populations in the borehole and the formations, the count-rates being generated during each of the time intervals. The background-corrected count-rate measurements are iteratively fitted to exponential curves using a least squares technique to simultaneously derive signals representing borehole component and formation component of the thermal neutron decay time. The signals are recorded as a function of borehole depth. (author)

  17. Novel Faraday cup for the simultaneous observation and measurement of ion-beam currents

    Wei, C.; Seidman, D.N.

    1977-01-01

    A novel Faraday cup is described which allows the simultaneous observation and measurement of ion-beam currents. The Faraday cup is constructed around a Galileo channel electron multiplier array (CEMA), which serves as the basis of an internal image intensification system (a gain of >10 4 ) for the observation of the ion beam; the CEMA also acts as a collector for the ion current which is measured by a Keithley 602 electrometer. The ion current is integrated by a simple and inexpensive dosimeter; the electronic circuit for the dosimeter is described. The application of the Faraday cup to the observation and measurement of a 30-keV Ar + ion beam is presented as an illustrative example. We have also employed this Faraday cup to observe and measure 30-keV Cr + , Mo + , or W + , and 18-keV Au + ion beams employed for the in situ irradiation of field-ion microscope specimens

  18. Increased phase synchronization during continuous face integration measured simultaneously with EEG and fMRI.

    Kottlow, Mara; Jann, Kay; Dierks, Thomas; Koenig, Thomas

    2012-08-01

    Gamma zero-lag phase synchronization has been measured in the animal brain during visual binding. Human scalp EEG studies used a phase locking factor (trial-to-trial phase-shift consistency) or gamma amplitude to measure binding but did not analyze common-phase signals so far. This study introduces a method to identify networks oscillating with near zero-lag phase synchronization in human subjects. We presented unpredictably moving face parts (NOFACE) which - during some periods - produced a complete schematic face (FACE). The amount of zero-lag phase synchronization was measured using global field synchronization (GFS). GFS provides global information on the amount of instantaneous coincidences in specific frequencies throughout the brain. Gamma GFS was increased during the FACE condition. To localize the underlying areas, we correlated gamma GFS with simultaneously recorded BOLD responses. Positive correlates comprised the bilateral middle fusiform gyrus and the left precuneus. These areas may form a network of areas transiently synchronized during face integration, including face-specific as well as binding-specific regions and regions for visual processing in general. Thus, the amount of zero-lag phase synchronization between remote regions of the human visual system can be measured with simultaneously acquired EEG/fMRI. Copyright © 2012 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  19. Spacecraft operations

    Sellmaier, Florian; Schmidhuber, Michael

    2015-01-01

    The book describes the basic concepts of spaceflight operations, for both, human and unmanned missions. The basic subsystems of a space vehicle are explained in dedicated chapters, the relationship of spacecraft design and the very unique space environment are laid out. Flight dynamics are taught as well as ground segment requirements. Mission operations are divided into preparation including management aspects, execution and planning. Deep space missions and space robotic operations are included as special cases. The book is based on a course held at the German Space Operation Center (GSOC).

  20. Internet Technology on Spacecraft

    Rash, James; Parise, Ron; Hogie, Keith; Criscuolo, Ed; Langston, Jim; Powers, Edward I. (Technical Monitor)

    2000-01-01

    The Operating Missions as Nodes on the Internet (OMNI) project has shown that Internet technology works in space missions through a demonstration using the UoSAT-12 spacecraft. An Internet Protocol (IP) stack was installed on the orbiting UoSAT-12 spacecraft and tests were run to demonstrate Internet connectivity and measure performance. This also forms the basis for demonstrating subsequent scenarios. This approach provides capabilities heretofore either too expensive or simply not feasible such as reconfiguration on orbit. The OMNI project recognized the need to reduce the risk perceived by mission managers and did this with a multi-phase strategy. In the initial phase, the concepts were implemented in a prototype system that includes space similar components communicating over the TDRS (space network) and the terrestrial Internet. The demonstration system includes a simulated spacecraft with sample instruments. Over 25 demonstrations have been given to mission and project managers, National Aeronautics and Space Administration (NASA), Department of Defense (DoD), contractor technologists and other decisions makers, This initial phase reached a high point with an OMNI demonstration given from a booth at the Johnson Space Center (JSC) Inspection Day 99 exhibition. The proof to mission managers is provided during this second phase with year 2000 accomplishments: testing the use of Internet technologies onboard an actual spacecraft. This was done with a series of tests performed using the UoSAT-12 spacecraft. This spacecraft was reconfigured on orbit at very low cost. The total period between concept and the first tests was only 6 months! On board software was modified to add an IP stack to support basic IP communications. Also added was support for ping, traceroute and network timing protocol (NTP) tests. These tests show that basic Internet functionality can be used onboard spacecraft. The performance of data was measured to show no degradation from current

  1. New bioreactor for in situ simultaneous measurement of bioluminescence and cell density

    Picart, Pascal; Bendriaa, Loubna; Daniel, Philippe; Horry, Habib; Durand, Marie-José; Jouvanneau, Laurent; Thouand, Gérald

    2004-03-01

    This article presents a new device devoted to the simultaneous measurement of bioluminescence and optical density of a bioluminescent bacterial culture. It features an optoelectronic bioreactor with a fully autoclavable module, in which the bioluminescent bacteria are cultivated, a modulated laser diode dedicated to optical density measurement, and a detection head for the acquisition of both bioluminescence and optical density signals. Light is detected through a bifurcated fiber bundle. This setup allows the simultaneous estimation of the bioluminescence and the cell density of the culture medium without any sampling. The bioluminescence is measured through a highly sensitive photomultiplier unit which has been photometrically calibrated to allow light flux measurements. This was achieved by considering the bioluminescence spectrum and the full optical transmission of the device. The instrument makes it possible to measure a very weak light flux of only a few pW. The optical density is determined through the laser diode and a photodiode using numerical synchronous detection which is based on the power spectrum density of the recorded signal. The detection was calibrated to measure optical density up to 2.5. The device was validated using the Vibrio fischeri bacterium which was cultivated under continuous culture conditions. A very good correlation between manual and automatic measurements processed with this instrument has been demonstrated. Furthermore, the optoelectronic bioreactor enables determination of the luminance of the bioluminescent bacteria which is estimated to be 6×10-5 W sr-1 m-2 for optical density=0.3. Experimental results are presented and discussed.

  2. Bainitic transformation behavior studied by simultaneous neutron diffraction and dilatometric measurement

    Koo, Minseo; Xu, Pingguang; Tomota, Yo; Suzuki, Hiroshi

    2009-01-01

    Bainitic transformation behavior has firstly been observed using in situ neutron diffraction with an angular dispersive method for a hard bainite steel. The dilatometric measurement was carried out simultaneously with the neutron experiment where changes in (1 1 1) austenite and (1 1 0) ferrite diffraction profiles were monitored during heating, cooling and holding at a transformation temperature. The neutron experiments results agree with dilatometry results. They appear to have found that the austenite peak broadening occurs after the onset of bainitic transformation but not before.

  3. Method and apparatus for simultaneously measuring a plurality of spectral wavelengths present in electromagnetic radiation

    Buican, Tudor N.; Martin, John C.

    1990-01-01

    An apparatus and method simultaneously measures a plurality of spectral wavelengths present in electromagnetic radiation. A modulatable birefringent optical element is employed to divide a polarized light beam into two components, thereby producing a phase difference in two resulting light beams such that the two beams can be made to interfere with one another when recombined, the interference pattern providing the wavelength information required for the analysis of the incident light. The interferometer thus created performs in a similar manner to a Michelson interferometer, but with no moving parts, and with a resolution dependent on the degree of phase shift introduced by the modulator.

  4. Simultaneous measurement of temperature and humidity with microstructured polymer optical fiber Bragg gratings

    Woyessa, Getinet; Pedersen, Jens Kristian Mølgaard; Fasano, Andrea

    2017-01-01

    A microstructured polymer optical fiber (mPOF) Bragg grating sensor system for the simultaneous measurement of temperature and relative humidity (RH) has been developed and characterized. The sensing head is based on two in-line fiber Bragg gratings recorded in a mPOF. The sensor system has a root...... mean square deviation of 1.04 % RH and 0.8 °C in the range 10 to 90% RH and 20 to 80 °C. The proposed sensor system is easy to fabricate, cheap and compact....

  5. Tamper temperature and compression from simultaneous proton and alpha-particle measurements in laser fusion experiments

    Cover, R.A.; Kubis, J.J.; Mayer, F.J.; Slater, D.C.

    1978-01-01

    The energy loss per unit path length for a charged particle incident on a spatially uniform isothermal Maxwellian plasma is a function of the temperature and density of the medium. Within this model the temperature and compression rhoΔr of the tamper of a laser-driven microshell target can be accurately determined, in the absence of electrostatic acceleration, by the simultaneous measurement of the energy loss from 3.52-MeV α particles from D-T reactions and 3.02-MeV protons from D-D reactions

  6. Device for simultaneous measurements of the optical and dielectric properties of hydrogels

    Gómez-Galván, F; Lara-Ceniceros, T; Mercado-Uribe, H

    2012-01-01

    We have designed an experimental device to simultaneously measure the light transmittance and dielectric properties of thermo-sensitive hydrogels. We have used this device to study poly(N-isopropylacrylamide) samples in order to understand the mechanism of water deliverance during the phase transition such hydrogels normally exhibit. We found that the phase transition can be observed dielectrically at low frequencies, when the isothermals obtained during the heating of the samples separate into two groups. The phenomenon occurs due to the increase of ions caused by the dissociation of water molecules released by the polymer, and corresponds to the drop of the optical transmittance

  7. Simultaneous measurement of passage through the restriction point and MCM loading in single cells

    Håland, T. W.; Boye, E.; Stokke, T.; Grallert, B.; Syljuåsen, R. G.

    2015-01-01

    Passage through the Retinoblastoma protein (RB1)-dependent restriction point and the loading of minichromosome maintenance proteins (MCMs) are two crucial events in G1-phase that help maintain genome integrity. Deregulation of these processes can cause uncontrolled proliferation and cancer development. Both events have been extensively characterized individually, but their relative timing and inter-dependence remain less clear. Here, we describe a novel method to simultaneously measure MCM loading and passage through the restriction point. We exploit that the RB1 protein is anchored in G1-phase but is released when hyper-phosphorylated at the restriction point. After extracting cells with salt and detergent before fixation we can simultaneously measure, by flow cytometry, the loading of MCMs onto chromatin and RB1 binding to determine the order of the two events in individual cells. We have used this method to examine the relative timing of the two events in human cells. Whereas in BJ fibroblasts released from G0-phase MCM loading started mainly after the restriction point, in a significant fraction of exponentially growing BJ and U2OS osteosarcoma cells MCMs were loaded in G1-phase with RB1 anchored, demonstrating that MCM loading can also start before the restriction point. These results were supported by measurements in synchronized U2OS cells. PMID:26250117

  8. Spacecraft Attitude Determination

    Bak, Thomas

    This thesis describes the development of an attitude determination system for spacecraft based only on magnetic field measurements. The need for such system is motivated by the increased demands for inexpensive, lightweight solutions for small spacecraft. These spacecraft demands full attitude...... determination based on simple, reliable sensors. Meeting these objectives with a single vector magnetometer is difficult and requires temporal fusion of data in order to avoid local observability problems. In order to guaranteed globally nonsingular solutions, quaternions are generally the preferred attitude...... is a detailed study of the influence of approximations in the modeling of the system. The quantitative effects of errors in the process and noise statistics are discussed in detail. The third contribution is the introduction of these methods to the attitude determination on-board the Ørsted satellite...

  9. Method for simultaneous measurement of borehole and formation neutron decay-times

    Smith, H.D.; Arnold, D.M.

    1982-01-01

    A method is described of making in situ measurements of the thermal neutron decay time of earth formations in the vicinity of a wellbore. The borehole and earth formations are irradiated, with pulsed fast neutrons and, during the interval between neutron pulses, capture gamma radiation is measured in at least four, non-overlapping, contiguous time intervals. Count-rates representative of thermal neutron populations in the borehole and the formations are made during each of the time intervals. A background radiation measurement for correcting the count-rates is preferably also periodically made. The count-rates are combined to derive simultaneously the formation and borehole neutron lifetime components which are recorded as a function of borehole depth. (author)

  10. A transient divided-bar method for simultaneous measurements of thermal conductivity and thermal diffusivity

    Bording, Thue Sylvester; Nielsen, Søren Bom; Balling, Niels

    2016-01-01

    and volumetric heat capacity, and thereby also thermal diffusivity, are measured simultaneously. As the density of samples is easily determined independently, specific heat capacity may also be determined. Finite element formulation provides a flexible forward solution for heat transfer across the bar...... and thermal properties are estimated by inverse Monte Carlo modelling. This methodology enables a proper quantification of experimental uncertainties on measured thermal properties. The developed methodology was applied to laboratory measurements of various materials, including a standard ceramic material......-3 %, and for diffusivity uncertainty may be reduced to about 3-5 %. The main uncertainty originates from the presence of thermal contact resistance associated with the internal interfaces of the bar. They are not resolved during inversion, and it is highly important that they are minimized by careful sample preparation....

  11. Simultaneous reconstruction of permittivity and conductivity using multi-frequency admittance measurement in electrical capacitance tomography

    Zhang, Maomao; Soleimani, Manuchehr

    2016-01-01

    Electrical capacitance tomography (ECT) is an imaging method mainly capable of reconstructing dielectric permittivity. Generally, the reactance part of complex admittance is measured in a selected frequency. This paper presents for the first time an in depth and systematic analysis of complex admittance data for simultaneous reconstruction of both electrical conductivity and dielectric permittivity. A complex-valued forward model, Jacobian matrix and inverse solution are developed in the time harmonic excitation mode to allow for multi-frequency measurements. Realistic noise models are used to evaluate the performance of complex admittance ECT in a range of excitation frequencies. This paper demonstrates far greater potential for ECT as a versatile imaging tool through novel analysis of complex admittance imaging using a dual conductivity permittivity inversion method. The paper demonstrates that various classes of contactless capacitance based measurement devices can be analysed through complex multi-frequency ECT. (paper)

  12. Quantitative and simultaneous non-invasive measurement of skin hydration and sebum levels

    Ezerskaia, Anna; Pereira, S. F.; Urbach, H. Paul; Verhagen, Rieko; Varghese, Babu

    2016-01-01

    We report a method on quantitative and simultaneous non-contact in-vivo hydration and sebum measurements of the skin using an infrared optical spectroscopic set-up. The method utilizes differential detection with three wavelengths 1720, 1750, and 1770 nm, corresponding to the lipid vibrational bands that lay “in between” the prominent water absorption bands. We have used an emulsifier containing hydro- and lipophilic components to mix water and sebum in various volume fractions which was applied to the skin to mimic different oily-dry skin conditions. We also measured the skin sebum and hydration values on the forehead under natural conditions and its variations to external stimuli. Good agreement was found between our experimental results and reference values measured using conventional biophysical methods such as Corneometer and Sebumeter. PMID:27375946

  13. Simultaneous, Unsteady PIV and Photogrammetry Measurements of a Tension-Cone Decelerator in Subsonic Flow

    Schairer, Edward T.; Heineck, James T.; Walker, Louise Ann; Kushner, Laura Kathryn; Zilliac, Gregory

    2010-01-01

    This paper describes simultaneous, synchronized, high-frequency measurements of both unsteady flow in the wake of a tension-cone decelerator in subsonic flow (by PIV) and the unsteady shape of the decelerator (by photogrammetry). The purpose of these measurements was to develop the test techniques necessary to validate numerical methods for computing fluid-structure interactions of flexible decelerators. A critical need for this effort is to map fabric surfaces that have buckled or wrinkled so that code developers can accurately represent them. This paper describes a new photogrammetric technique that performs this measurement. The work was done in support of the Entry, Descent, and Landing discipline within the Supersonics Project of NASA s Fundamental Aeronautics Program.

  14. Simultaneous measurement of surface tension and viscosity using freely decaying oscillations of acoustically levitated droplets

    Kremer, J.; Kilzer, A.; Petermann, M.

    2018-01-01

    Oscillations of small liquid drops around a spherical shape have been of great interest to scientists measuring physical properties such as interfacial tension and viscosity, over the last few decades. A powerful tool for contactless positioning is acoustic levitation, which has been used to simultaneously determine the surface tension and viscosity of liquids at ambient pressure. In order to extend this acoustic levitation measurement method to high pressure systems, the method is first evaluated under ambient pressure. To measure surface tension and viscosity using acoustically levitated oscillating drops, an image analysis method has to be developed and factors which may affect measurement, such as sound field or oscillation amplitude, have to be analyzed. In this paper, we describe the simultaneous measurement of surface tension and viscosity using freely decaying shape oscillations of acoustically levitated droplets of different liquids (silicone oils AK 5 and AK 10, squalane, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, and 1-octanol) in air. These liquids vary in viscosity from 2 to about 30 mPa s. An acoustic levitation system, including an optimized standing wave acoustic levitator and a high-speed camera, was used for this study. An image analysis was performed with a self-written Matlab® code. The frequency of oscillation and the damping constant, required for the determination of surface tension and viscosity, respectively, were calculated from the evolution of the equatorial and polar radii. The results and observations are compared to data from the literature in order to analyze the accuracy of surface tension and viscosity determination, as well as the effect of non-spherical drop shape or amplitude of oscillation on measurement.

  15. Simultaneous measurement of pO2 and perfusion in the rabbit kidney in vivo.

    O'Connor, Paul M; Anderson, Warwick P; Kett, Michelle M; Evans, Roger G

    2007-01-01

    Recently, a combined probe has been developed capable of simultaneous measurement of local tissue pO2 (fluorescence oximetry) and microvascular perfusion (laser Doppler flux) within the same local region. The aim of the current study was to test the utility of these combined probes to measure pO2 and perfusion in the kidney. Studies were performed in anesthetized, artificially ventilated rabbits (n=7). Baseline measurements of renal medullary perfusion and pO2 obtained using combined probes (537 +/- 110 units & 28.7 +/- 6.l mmHg, respectively) were indistinguishable from those obtained using independent probes (435 +/- 102 units & 26.9 +/- 6.4 mmHg). Baseline measurements of renal cortical pO2 were also similar between combined (9.7 +/- 1.6 mmHg) and independent probes (9.5 +/- 2.3 mmHg). Baseline levels of cortical perfusion however, were significantly greater when measured using independent probes (1130 +/- 114 units) compared to combined probes (622 +/- 59 units; P pO2 resulting from graded stimulation of the renal nerves were not significantly different when measured using combined probes to those obtained using independent probes. We conclude that combined probes are equally suitable to independent probes for tissue pO2 and microvascular perfusion measurement in the kidney. Our results raise some concerns regarding the accuracy of these OxyLite fluorescence probes for pO2 measurement in the kidney, particularly within the renal cortex.

  16. Simultaneous overlay and CD measurement for double patterning: scatterometry and RCWA approach

    Li, Jie; Liu, Zhuan; Rabello, Silvio; Dasari, Prasad; Kritsun, Oleg; Volkman, Catherine; Park, Jungchul; Singh, Lovejeet

    2009-03-01

    As optical lithography advances to 32 nm technology node and beyond, double patterning technology (DPT) has emerged as an attractive solution to circumvent the fundamental optical limitations. DPT poses unique demands on critical dimension (CD) uniformity and overlay control, making the tolerance decrease much faster than the rate at which critical dimension shrinks. This, in turn, makes metrology even more challenging. In the past, multi-pad diffractionbased overlay (DBO) using empirical approach has been shown to be an effective approach to measure overlay error associated with double patterning [1]. In this method, registration errors for double patterning were extracted from specially designed diffraction targets (three or four pads for each direction); CD variation is assumed negligible within each group of adjacent pads and not addressed in the measurement. In another paper, encouraging results were reported with a first attempt at simultaneously extracting overlay and CD parameters using scatterometry [2]. In this work, we apply scatterometry with a rigorous coupled wave analysis (RCWA) approach to characterize two double-patterning processes: litho-etch-litho-etch (LELE) and litho-freeze-litho-etch (LFLE). The advantage of performing rigorous modeling is to reduce the number of pads within each measurement target, thus reducing space requirement and improving throughput, and simultaneously extract CD and overlay information. This method measures overlay errors and CDs by fitting the optical signals with spectra calculated from a model of the targets. Good correlation is obtained between the results from this method and that of several reference techniques, including empirical multi-pad DBO, CD-SEM, and IBO. We also perform total measurement uncertainty (TMU) analysis to evaluate the overall performance. We demonstrate that scatterometry provides a promising solution to meet the challenging overlay metrology requirement in DPT.

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

    Zengling Ran

    2014-08-01

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

  18. Micro-structured optical fiber sensor for simultaneous measurement of temperature and refractive index

    Liu, Ying-gang; Liu, Xin; Ma, Cheng-ju; Zhou, Yu-min

    2018-03-01

    Through using micro-machining method for optical fiber sensor, a kind of miniature, compact and composite structural all-fiber sensor is presented. Based on manufacturing two micro-holes with certain distance in ordinary single-mode fiber Bragg grating (FBG) by excimer laser processing technique, we fabricate a dual Fabry-Perot-FBG (FP-FBG) composite fiber interferometric sensor, which can be used in simultaneous measurement for liquid's refractive index (RI) and temperature change. Due to every micro-hole and the dual micro-holes in fiber acting as different Fabry-Perot (FP) cavities, this kind of sensor has not only different RI sensitivities but also different temperature sensitivities, which are corresponding to the wavelength shifts of the fine interference fringes and spectral envelope, respectively. The experimental results show that the spectral wavelength shift keep better linear response for temperature and RI change, so that we can select the higher temperature and RI sensitivities as well as the analyzed sensitivities of FBG to utilize them for constituting a sensitivity coefficients matrix. Finally, the variations of liquid's temperature and RI are detected effectively, and the resolutions can reach to 0.1 °C and 1.0 ×10-5 RIU. These characteristics are what other single-type sensors don't have, so that this kind of all-fiber dual FP-FBG composite fiber interferometric sensor can be used in extremely tiny liquid environment for measuring different physical quantities simultaneously.

  19. A Compound Sensor for Simultaneous Measurement of Packing Density and Moisture Content of Silage.

    Meng, Delun; Meng, Fanjia; Sun, Wei; Deng, Shuang

    2017-12-28

    Packing density and moisture content are important factors in investigating the ensiling quality. Low packing density is a major cause of loss of sugar content. The moisture content also plays a determinant role in biomass degradation. To comprehensively evaluate the ensiling quality, this study focused on developing a compound sensor. In it, moisture electrodes and strain gauges were embedded into an ASABE Standard small cone for the simultaneous measurements of the penetration resistance (PR) and moisture content (MC) of silage. In order to evaluate the performance of the designed sensor and the theoretical analysis being used, relevant calibration and validation tests were conducted. The determination coefficients are 0.996 and 0.992 for PR calibration and 0.934 for MC calibration. The validation indicated that this measurement technique could determine the packing density and moisture content of the silage simultaneously and eliminate the influence of the friction between the penetration shaft and silage. In this study, we not only design a compound sensor but also provide an alternative way to investigate the ensiling quality which would be useful for further silage research.

  20. Twin-Core Fiber-Based Mach Zehnder Interferometer for Simultaneous Measurement of Strain and Temperature

    Kowal, Dominik; Urbanczyk, Waclaw; Mergo, Pawel

    2018-01-01

    In this paper we present an all-fiber interferometric sensor for the simultaneous measurement of strain and temperature. It is composed of a specially fabricated twin-core fiber spliced between two pieces of a single-mode fiber. Due to the refractive index difference between the two cores in a twin-core fiber, a differential interference pattern is produced at the sensor output. The phase response of the interferometer to strain and temperature is measured in the 850–1250 nm spectral range, showing zero sensitivity to strain at 1000 nm. Due to the significant difference in sensitivities to both parameters, our interferometer is suitable for two-parameter sensing. The simultaneous response of the interferometer to strain and temperature was studied using the two-wavelength interrogation method and a novel approach based on the spectral fitting of the differential phase response. As the latter technique uses all the gathered spectral information, it is more reliable and yields the results with better accuracy. PMID:29558386

  1. Simultaneous refractive index and thickness measurement with the transmission interferometric adsorption sensor

    Sannomiya, Takumi; Voeroes, Janos [Laboratory of Biosensors and Bioelectronics, Department of Information Technology and Electrical Engineering, ETH Zurich, 8092, Zurich (Switzerland); Balmer, Tobias E [Materials Research Center, ETH Zurich, 8093, Zurich (Switzerland); Heuberger, Manfred, E-mail: sannomiya@biomed.ee.ethz.c, E-mail: tobias.balmer@mat.ethz.c, E-mail: manfred.heuberger@empa.c, E-mail: janos.voros@biomed.ee.ethz.c [Laboratory for Surface Science and Technology, Department of Materials, ETH Zurich, 8093, Zurich (Switzerland)

    2010-10-13

    Refractive index and thickness of the adlayer are determined simultaneously using the transmission interferometric adsorption sensor (TInAS). Optical biosensors, where both refractive index and thickness of a homogeneous adlayer (thus the adsorbed mass) are determined simultaneously, so-called model-free biosensors, are important tools to investigate the adsorbed mass of biomolecules with unknown conformation. Our proposed calculation method enables model-free biosensing from a single spectrum acquired by a simple TInAS setup, namely using information of peak/dip positions as well as peak/dip intensities. The feasibility of this method was experimentally tested by adsorbing polyelectrolyte multilayer as well as biomolecules. To validate the new method also for the more intricate heterogeneous adlayer, the apparent refractive index and thickness were assessed theoretically by simulating a selection of different adsorbate configurations with the multiple multipole program (MMP). We found that a lateral inhomogeneity of the adsorbate (e.g. islands or adsorbed colloids) results in correct thickness and in reduced refractive index averaged in proportion to their density while vertically inhomogeneous density caused more complex responses. However, the apparent mass was always correct. Measurement errors can lead to significant errors in the apparent refractive index, particularly when the adlayer is very thin (<5 nm). This model-free TInAS technique would be useful not only for the measurement of adsorbed mass but also for the conformational analysis of the adsorbed molecules.

  2. Simultaneous measurement of refractive index and temperature based on intensity demodulation using matching grating method.

    Qi, Liang; Zhao, Chun-Liu; Kang, Juan; Jin, Yongxing; Wang, Jianfeng; Ye, Manping; Jin, Shangzhong

    2013-07-01

    A solution refractive index (SRI) and temperature simultaneous measurement sensor with intensity-demodulation system based on matching grating method were demonstrated. Long period grating written in a photonic crystal fiber (LPG-PCF), provides temperature stable and wavelength dependent optical intensity transmission. The reflective peaks of two fiber Bragg gratings (FBGs), one of which is etched then sensitive to both SRI and temperature, another (FBG2) is only sensitive to temperature, were located in the same linear range of the LPG-PCF's transmission spectrum. An identical FBG with FBG2 was chosen as a matching FBG. When environments (SRI and temperature) change, the wavelength shifts of the FBGs are translated effectively to the reflection intensity changes. By monitoring output lights of unmatching and matching paths, the SRI and temperature were deduced by a signal processing unit. Experimental results show that the simultaneous refractive index and temperature measurement system work well. The proposed sensor system is compact and suitable for in situ applications at lower cost.

  3. Comparison of causality analysis on simultaneously measured fMRI and NIRS signals during motor tasks.

    Anwar, Abdul Rauf; Muthalib, Makii; Perrey, Stephane; Galka, Andreas; Granert, Oliver; Wolff, Stephan; Deuschl, Guenther; Raethjen, Jan; Heute, Ulrich; Muthuraman, Muthuraman

    2013-01-01

    Brain activity can be measured using different modalities. Since most of the modalities tend to complement each other, it seems promising to measure them simultaneously. In to be presented research, the data recorded from Functional Magnetic Resonance Imaging (fMRI) and Near Infrared Spectroscopy (NIRS), simultaneously, are subjected to causality analysis using time-resolved partial directed coherence (tPDC). Time-resolved partial directed coherence uses the principle of state space modelling to estimate Multivariate Autoregressive (MVAR) coefficients. This method is useful to visualize both frequency and time dynamics of causality between the time series. Afterwards, causality results from different modalities are compared by estimating the Spearman correlation. In to be presented study, we used directionality vectors to analyze correlation, rather than actual signal vectors. Results show that causality analysis of the fMRI correlates more closely to causality results of oxy-NIRS as compared to deoxy-NIRS in case of a finger sequencing task. However, in case of simple finger tapping, no clear difference between oxy-fMRI and deoxy-fMRI correlation is identified.

  4. Simultaneous 3D-vibration measurement using a single laser beam device

    Brecher, Christian; Guralnik, Alexander; Baümler, Stephan

    2012-06-01

    Today's commercial solutions for vibration measurement and modal analysis are 3D-scanning laser doppler vibrometers, mainly used for open surfaces in the automotive and aerospace industries and the classic three-axial accelerometers in civil engineering, for most industrial applications in manufacturing environments, and particularly for partially closed structures. This paper presents a novel measurement approach using a single laser beam device and optical reflectors to simultaneously perform 3D-dynamic measurement as well as geometry measurement of the investigated object. We show the application of this so called laser tracker for modal testing of structures on a mechanical manufacturing shop floor. A holistic measurement method is developed containing manual reflector placement, semi-automated geometric modeling of investigated objects and fully automated vibration measurement up to 1000 Hz and down to few microns amplitude. Additionally the fast set up dynamic measurement of moving objects using a tracking technique is presented that only uses the device's own functionalities and does neither require a predefined moving path of the target nor an electronic synchronization to the moving object.

  5. Simultaneous streak and frame interferometry for electron density measurements of laser produced plasmas

    Quevedo, H. J., E-mail: hjquevedo@utexas.edu; McCormick, M.; Wisher, M.; Bengtson, Roger D.; Ditmire, T. [Center for High Energy Density Science, Department of Physics, University of Texas at Austin, Austin, Texas 78712 (United States)

    2016-01-15

    A system of two collinear probe beams with different wavelengths and pulse durations was used to capture simultaneously snapshot interferograms and streaked interferograms of laser produced plasmas. The snapshots measured the two dimensional, path-integrated, electron density on a charge-coupled device while the radial temporal evolution of a one dimensional plasma slice was recorded by a streak camera. This dual-probe combination allowed us to select plasmas that were uniform and axisymmetric along the laser direction suitable for retrieving the continuous evolution of the radial electron density of homogeneous plasmas. Demonstration of this double probe system was done by measuring rapidly evolving plasmas on time scales less than 1 ns produced by the interaction of femtosecond, high intensity, laser pulses with argon gas clusters. Experiments aimed at studying homogeneous plasmas from high intensity laser-gas or laser-cluster interaction could benefit from the use of this probing scheme.

  6. Development of a combination detector system for simultaneous measurement of Alpha and Beta/Gamma radioactivity

    Thakur, Vaishali M.; Ashokkumar, P.; Rekha, A.K.; Jain, Amit; Rath, D.P.; Chaudhury, Probal; Chaudhari, L.M.

    2018-01-01

    Analysis of various samples for α and β/γ radioactivity is carried out in radiological laboratories. Using independent α and β/γ counting systems such measurements are done separately for same sample. In order to address the requirement of simultaneous measurement of α and β/γ activity content of radioactive samples, a counting system using combination of two detectors has been developed. Activity deposited on a 2 mm deep 30 mm diameter aluminum planchette was counted under the detector combination consisting of a ZnS(Ag) and plastic scintillator for α and β/γ respectively. The design and fabrication of the combination detector, development of electronics associated with the system, its characterization and application are presented here

  7. Simultaneous Microwave Imaging System for Density and Temperature Fluctuation Measurements on TEXTOR

    Park, H.; Mazzucato, E.; Munsat, T.; Domier, C.W.; Johnson, M.; Luhmann, N.C. Jr.; Wang, J.; Xia, Z.; Classen, I.G.J.; Donne, A.J.H.; Pol, M.J. van de

    2004-01-01

    Diagnostic systems for fluctuation measurements in plasmas have, of necessity, evolved from simple 1-D systems to multi-dimensional systems due to the complexity of the MHD and turbulence physics of plasmas illustrated by advanced numerical simulations. Using the recent significant advancements in millimeter wave imaging technology, Microwave Imaging Reflectometry (MIR) and Electron Cyclotron Emission Imaging (ECEI), simultaneously measuring density and temperature fluctuations, are developed for TEXTOR. The MIR system was installed on TEXTOR and the first experiment was performed in September, 2003. Subsequent MIR campaigns have yielded poloidally resolved spectra and assessments of poloidal velocity. The new 2-D ECE Imaging system (with a total of 128 channels), installed on TEXTOR in December, 2003, successfully captured a true 2-D images of Te fluctuations of m=1 oscillation (''sawteeth'') near the q ∼ 1 surface for the first time

  8. A method and tool for combining differential or inclusive measurements obtained with simultaneously constrained uncertainties

    Kieseler, Jan

    2017-11-01

    A method is discussed that allows combining sets of differential or inclusive measurements. It is assumed that at least one measurement was obtained with simultaneously fitting a set of nuisance parameters, representing sources of systematic uncertainties. As a result of beneficial constraints from the data all such fitted parameters are correlated among each other. The best approach for a combination of these measurements would be the maximization of a combined likelihood, for which the full fit model of each measurement and the original data are required. However, only in rare cases this information is publicly available. In absence of this information most commonly used combination methods are not able to account for these correlations between uncertainties, which can lead to severe biases as shown in this article. The method discussed here provides a solution for this problem. It relies on the public result and its covariance or Hessian, only, and is validated against the combined-likelihood approach. A dedicated software package implementing this method is also presented. It provides a text-based user interface alongside a C++ interface. The latter also interfaces to ROOT classes for simple combination of binned measurements such as differential cross sections.

  9. A method and tool for combining differential or inclusive measurements obtained with simultaneously constrained uncertainties

    Kieseler, Jan [CERN, Geneva (Switzerland)

    2017-11-15

    A method is discussed that allows combining sets of differential or inclusive measurements. It is assumed that at least one measurement was obtained with simultaneously fitting a set of nuisance parameters, representing sources of systematic uncertainties. As a result of beneficial constraints from the data all such fitted parameters are correlated among each other. The best approach for a combination of these measurements would be the maximization of a combined likelihood, for which the full fit model of each measurement and the original data are required. However, only in rare cases this information is publicly available. In absence of this information most commonly used combination methods are not able to account for these correlations between uncertainties, which can lead to severe biases as shown in this article. The method discussed here provides a solution for this problem. It relies on the public result and its covariance or Hessian, only, and is validated against the combined-likelihood approach. A dedicated software package implementing this method is also presented. It provides a text-based user interface alongside a C++ interface. The latter also interfaces to ROOT classes for simple combination of binned measurements such as differential cross sections. (orig.)

  10. A new method for simultaneous measurement of convective and radiative heat flux in car underhood applications

    Khaled, M; Garnier, B; Peerhossaini, H; Harambat, F

    2010-01-01

    A new experimental technique is presented that allows simultaneous measurement of convective and radiative heat flux in the underhood. The goal is to devise an easily implemented and accurate experimental method for application in the vehicle underhood compartment. The new method is based on a technique for heat-flux measurement developed by the authors (Heat flow (flux) sensors for measurement of convection, conduction and radiation heat flow 27036-2, © Rhopoint Components Ltd, Hurst Green, Oxted, RH8 9AX, UK) that uses several thermocouples in the thickness of a thermal resistive layer (foil heat-flux sensor). The method proposed here uses a pair of these thermocouples with different radiative properties. Measurements validating this novel technique are carried out on a flat plate with a prescribed constant temperature in both natural- and forced-convection flow regimes. The test flat plate is instrumented by this new technique, and also with a different technique that is intrusive but very accurate, used as reference here (Bardon J P and Jarny Y 1994 Procédé et dispositif de mesure transitoire de température et flux surfacique Brevet n°94.011996, 22 February). Discrepancies between the measurements by the two techniques are less than 10% for both convective and radiative heat flux. Error identification and sensitivity analysis of the new method are also presented

  11. Luminescent two-color tracer particles for simultaneous velocity and temperature measurements in microfluidics

    Massing, J; Kähler, C J; Cierpka, C; Kaden, D

    2016-01-01

    The simultaneous and non-intrusive measurement of temperature and velocity fields in flows is of great scientific and technological interest. To sample the velocity and temperature, tracer particle based approaches have been developed, where the velocity is measured using PIV or PTV and the temperature is obtained from the intensity (LIF, thermographic phosphors) or frequency (TLC) of the light emitted or reflected by the tracer particles. In this article, a measurement technique is introduced, that relates the luminescent intensity ratio of individual dual-color luminescent tracer particles to temperature. Different processing algorithms are tested on synthetic particle images and compared with respect to their accuracy in estimating the intensity ratio. Furthermore, polymer particles which are doped with the temperature sensitive dye europium (III) thenoyltrifluoroacetonate (EuTTA) and the nearly temperature insensitive reference dye perylene are characterized as valid tracers. The results show a reduction of the temperature measurement uncertainty of almost 40% (95% confidence interval) compared to previously reported luminescent particle based measurement techniques for microfluidics. (paper)

  12. Simultaneous measurement of glucose transport and utilization in the human brain

    Shestov, Alexander A.; Emir, Uzay E.; Kumar, Anjali; Henry, Pierre-Gilles; Seaquist, Elizabeth R.

    2011-01-01

    Glucose is the primary fuel for brain function, and determining the kinetics of cerebral glucose transport and utilization is critical for quantifying cerebral energy metabolism. The kinetic parameters of cerebral glucose transport, KMt and Vmaxt, in humans have so far been obtained by measuring steady-state brain glucose levels by proton (1H) NMR as a function of plasma glucose levels and fitting steady-state models to these data. Extraction of the kinetic parameters for cerebral glucose transport necessitated assuming a constant cerebral metabolic rate of glucose (CMRglc) obtained from other tracer studies, such as 13C NMR. Here we present new methodology to simultaneously obtain kinetic parameters for glucose transport and utilization in the human brain by fitting both dynamic and steady-state 1H NMR data with a reversible, non-steady-state Michaelis-Menten model. Dynamic data were obtained by measuring brain and plasma glucose time courses during glucose infusions to raise and maintain plasma concentration at ∼17 mmol/l for ∼2 h in five healthy volunteers. Steady-state brain vs. plasma glucose concentrations were taken from literature and the steady-state portions of data from the five volunteers. In addition to providing simultaneous measurements of glucose transport and utilization and obviating assumptions for constant CMRglc, this methodology does not necessitate infusions of expensive or radioactive tracers. Using this new methodology, we found that the maximum transport capacity for glucose through the blood-brain barrier was nearly twofold higher than maximum cerebral glucose utilization. The glucose transport and utilization parameters were consistent with previously published values for human brain. PMID:21791622

  13. Development of compact DOI-measurable PET detectors for simultaneous PET/MR Imaging

    Shao, Yiping; Sun, Xishan [University of Texas MD Anderson Cancer Center (United States); Lou, Kai [Rice University (United States)

    2015-05-18

    It is critically needed yet challenging to develop compact PET detectors with high sensitivity and uniform, high imaging resolution for improving the performance of simultaneous PET/MR imaging, particularly for an integrated/inserted small-bore system. Using the latest “edge-less” SiPM arrays for DOI measurement using the design of dual-ended-scintillator readout, we developed several compact PET detectors suited for PET/MR imaging. Each detector consists of one LYSO array with each end coupled to a SiPM array. Multiple detectors can be seamlessly tiled together along all sides to form a large detector panel. Detectors with 1.5x1.5 and 2.0x2.0 mm crystals at 20 or 30 mm lengths were studied. Readout of individual SiPM or capacitor-based signal multiplexing was used to transfer 3D interaction position-coded analog signals through flexible-print-circuit cables to dedicated ASIC frontend electronics to output digital timing pulses that encode interaction information. These digital pulses can be transferred to, through standard LVDS cables, and decoded by a FPGA-based data acquisition positioned outside the MRI scanner for coincidence event selection. Initial detector performance measurement shows excellent crystal identification even with 30 mm long crystals, ~18% and 2.8 ns energy and timing resolutions, and around 2-3 mm DOI resolution. A large size detector panel can be scaled up with these modular detectors and different PET systems can be flexibly configured with the scalable readout electronics and data acquisition, providing an important design advantage for different system and application requirements. It is expected that standard shielding of detectors, electronics and signal transfer lines can be applied for simultaneous PET/MR imaging applications, with desired DOI measurement capability to enhance the PET performance and image quality.

  14. Development of compact DOI-measurable PET detectors for simultaneous PET/MR Imaging

    Shao, Yiping; Sun, Xishan; Lou, Kai

    2015-01-01

    It is critically needed yet challenging to develop compact PET detectors with high sensitivity and uniform, high imaging resolution for improving the performance of simultaneous PET/MR imaging, particularly for an integrated/inserted small-bore system. Using the latest “edge-less” SiPM arrays for DOI measurement using the design of dual-ended-scintillator readout, we developed several compact PET detectors suited for PET/MR imaging. Each detector consists of one LYSO array with each end coupled to a SiPM array. Multiple detectors can be seamlessly tiled together along all sides to form a large detector panel. Detectors with 1.5x1.5 and 2.0x2.0 mm crystals at 20 or 30 mm lengths were studied. Readout of individual SiPM or capacitor-based signal multiplexing was used to transfer 3D interaction position-coded analog signals through flexible-print-circuit cables to dedicated ASIC frontend electronics to output digital timing pulses that encode interaction information. These digital pulses can be transferred to, through standard LVDS cables, and decoded by a FPGA-based data acquisition positioned outside the MRI scanner for coincidence event selection. Initial detector performance measurement shows excellent crystal identification even with 30 mm long crystals, ~18% and 2.8 ns energy and timing resolutions, and around 2-3 mm DOI resolution. A large size detector panel can be scaled up with these modular detectors and different PET systems can be flexibly configured with the scalable readout electronics and data acquisition, providing an important design advantage for different system and application requirements. It is expected that standard shielding of detectors, electronics and signal transfer lines can be applied for simultaneous PET/MR imaging applications, with desired DOI measurement capability to enhance the PET performance and image quality.

  15. Simultaneous time-space resolved reflectivity and interferometric measurements of dielectrics excited with femtosecond laser pulses

    Garcia-Lechuga, M.; Haahr-Lillevang, L.; Siegel, J.; Balling, P.; Guizard, S.; Solis, J.

    2017-06-01

    Simultaneous time-and-space resolved reflectivity and interferometric measurements over a temporal span of 300 ps have been performed in fused silica and sapphire samples excited with 800 nm, 120 fs laser pulses at energies slightly and well above the ablation threshold. The experimental results have been simulated in the frame of a multiple-rate equation model including light propagation. The comparison of the temporal evolution of the reflectivity and the interferometric measurements at 400 nm clearly shows that the two techniques interrogate different material volumes during the course of the process. While the former is sensitive to the evolution of the plasma density in a very thin ablating layer at the surface, the second yields an averaged plasma density over a larger volume. It is shown that self-trapped excitons do not appreciably contribute to carrier relaxation in fused silica at fluences above the ablation threshold, most likely due to Coulomb screening effects at large excited carrier densities. For both materials, at fluences well above the ablation threshold, the maximum measured plasma reflectivity shows a saturation behavior consistent with a scattering rate proportional to the plasma density in this fluence regime. Moreover, for both materials and for pulse energies above the ablation threshold and delays in the few tens of picoseconds range, a simultaneous "low reflectivity" and "low transmission" behavior is observed. Although this behavior has been identified in the past as a signature of femtosecond laser-induced ablation, its origin is alternatively discussed in terms of the optical properties of a material undergoing strong isochoric heating, before having time to substantially expand or exchange energy with the surrounding media.

  16. Inter-arm Differences in Simultaneous Blood Pressure Measurements in Ambulatory Patients without Cardiovascular Diseases.

    Kim, Kyoung Bog; Oh, Mi Kyeong; Kim, Haa Gyoung; Ki, Ji Hoon; Lee, Soo Hee; Kim, Su Min

    2013-03-01

    It has traditionally been known that there is normally a difference in blood pressure (BP) between the two arms; there is at least 20 mm Hg difference in the systolic blood pressure (SBP) and 10 mm Hg difference in the diastolic blood pressure (DBP). However, recent epidemiologic studies have shown that there are between-arm differences of arm differences in simultaneous BP measurements obtained from ambulatory patients without cardiovascular diseases and to identify the factors associated these differences. We examined 464 patients who visited the outpatient clinic of Gangneung Asan Hospital clinical department. For the current analysis, we excluded patients with ischemic heart disease, stroke, arrhythmia, congestive heart failure, or hyperthyroidism. Simultaneous BP measurements were obtained using the Omron MX3 BP monitor in both arms. The inter-arm difference (IAD) in BP was expressed as the relative difference (right-arm BP [R] minus left-arm BP [L]: R - L) and the absolute difference (|R - L|). The mean absolute IAD in SBP and DBP were 3.19 ± 2.38 and 2.41 ± 1.59 mm Hg, respectively, in men and 2.61 ± 2.18 and 2.25 ± 2.01 mm Hg, respectively, in women. In men, there were 83.8% of patients with the IAD in SBP of ≤ 6 mm Hg, 98.1% with the IAD in SBP of ≤ 10 mm Hg, 96.5% with the IAD in DBP of ≤ 6 mm Hg and 0% with the IAD in DBP of > 10 mm Hg. In women, 89.6% of patients had IAD in SBP of ≤ 6 mm Hg, 92.1% with IAD in DBP of ≤ 6 mm Hg, and 0% with IAD in SBP of > 10 mm Hg or IAD in DBP of > 10 mm Hg. Gangneung Asan Hospital clinical series of patients showed that the absolute IAD in SBP had a significant correlation with cardiovascular risk factors such as the 10-year Framingham cardiac risk scores and higher BP in men and higher BP in women. However, the absolute IAD in SBP and DBP had no significant correlation with the age, obesity, smoking, drinking, hyperlipidemia, diabetes, metabolic syndrome, and renal function. Our results showed that there

  17. Simultaneous Measurements of Soil CO2 and CH4 Fluxes Using Laser Absorption Spectroscopy

    Rachhpal S. Jassal

    2016-04-01

    Full Text Available We present a method of simultaneously measuring soil CO and CH fluxes using a laser-based cavity ring-down spectrometer (CRDS coupled to an automated non-steady-state chamber system. The differential equation describing the change in the greenhouse gas (GHG mixing ratio in the chamber headspace following lid closure is solved for the condition when a small flow rate of chamber headspace air is pulled through the CRDS by an external pump and exhausted to the atmosphere. The small flow rate allows calculation of fluxes assuming linear relationships between the GHG mixing ratios and chamber lid closure times of a few minutes. We also calibrated the chambers for effective volume ( and show that adsorption of the GHGs on the walls of the chamber caused to be 7% higher than the geometric volume, with the near-surface soil porosity causing another 4% increase in .

  18. Simultaneous measurement of amyloid fibril formation by dynamic light scattering and fluorescence reveals complex aggregation kinetics.

    Aaron M Streets

    Full Text Available An apparatus that combines dynamic light scattering and Thioflavin T fluorescence detection is used to simultaneously probe fibril formation in polyglutamine peptides, the aggregating subunit associated with Huntington's disease, in vitro. Huntington's disease is a neurodegenerative disorder in a class of human pathologies that includes Alzheimer's and Parkinson's disease. These pathologies are all related by the propensity of their associated protein or polypeptide to form insoluble, β-sheet rich, amyloid fibrils. Despite the wide range of amino acid sequence in the aggregation prone polypeptides associated with these diseases, the resulting amyloids display strikingly similar physical structure, an observation which suggests a physical basis for amyloid fibril formation. Thioflavin T fluorescence reports β-sheet fibril content while dynamic light scattering measures particle size distributions. The combined techniques allow elucidation of complex aggregation kinetics and are used to reveal multiple stages of amyloid fibril formation.

  19. Simultaneous measurements of the OH(8,3) band and 015577A airglow emissions

    Takahashi, H.; Sahai, Y.; Clemesha, B.R.; Simonich, D.M.; Batista, P.P.; Teixeira, N.R.

    1981-01-01

    Simultaneous measurements of the night airglow OH(8,3) band and OI 5577A have been made at Cachoeira Paulista (22.7 0 S, 45,2 0 W) during June-August 1976. Correlations between the nocturnal variations of these emissions and also with the OH rotational temperature are presented. It is found that OH (8,3) is correlated with the rotational temperature but with a time lag of about 1 hour. The variations of 5577A lead the OH (8,3) by about 2 to 3 hours. The rotational temperature co-varies with 5577A, rather than OH (8,3) and there is no significant time lag. Based on the correlation study, the nocturnal variations of the two emissions can be explained by the atmospheric density perturbation caused by solar tides and internal gravity waves. (Author) [pt

  20. A Simultaneous Measurement of the QCD Colour Factors and the Strong Coupling

    Abbiendi, G.; Akesson, P.F.; Alexander, G.; Allison, John; Anagnostou, G.; Anderson, K.J.; Arcelli, S.; Asai, S.; Axen, D.; Azuelos, G.; Bailey, I.; Ball, H.; Barberio, E.; Barlow, Roger J.; Batley, R.J.; Behnke, T.; Bell, Kenneth Watson; Bella, G.; Bellerive, A.; Benelli, G.; Bethke, S.; Biebel, O.; Bloodworth, I.J.; Boeriu, O.; Bock, P.; Bohme, J.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Brigliadori, L.; Brown, Robert M.; Burckhart, H.J.; Cammin, J.; Capiluppi, P.; Carnegie, R.K.; Caron, B.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Clarke, P.E.L.; Clay, E.; Cohen, I.; Couchman, J.; Csilling, A.; Cuffiani, M.; Dado, S.; Dallavalle, G.Marco; Dallison, S.; De Roeck, A.; De Wolf, E.A.; Dervan, P.; Desch, K.; Dienes, B.; Dixit, M.S.; Donkers, M.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Estabrooks, P.G.; Etzion, E.; Fabbri, F.; Fanti, M.; Feld, L.; Ferrari, P.; Fiedler, F.; Fleck, I.; Ford, M.; Frey, A.; Furtjes, A.; Futyan, D.I.; Gagnon, P.; Gary, J.W.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Glenzinski, D.; Goldberg, J.; Grandi, C.; Graham, K.; Gross, E.; Grunhaus, J.; Gruwe, M.; Gunther, P.O.; Gupta, A.; Hajdu, C.; Hanson, G.G.; Harder, K.; Harel, A.; Harin-Dirac, M.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Hensel, C.; Herten, G.; Heuer, R.D.; Hill, J.C.; Hoffman, Kara Dion; Homer, R.J.; Honma, A.K.; Horvath, D.; Hossain, K.R.; Howard, R.; Huntemeyer, P.; Igo-Kemenes, P.; Ishii, K.; Jawahery, A.; Jeremie, H.; Jones, C.R.; Jovanovic, P.; Junk, T.R.; Kanaya, N.; Kanzaki, J.; Karapetian, G.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kim, D.H.; Klein, K.; Klier, A.; Kluth, S.; Kobayashi, T.; Kobel, M.; Kokott, T.P.; Komamiya, S.; Kowalewski, Robert V.; Kamer, T.; Kress, T.; Krieger, P.; von Krogh, J.; Krop, D.; Kuhl, T.; Kupper, M.; Kyberd, P.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Lawson, I.; Layter, J.G.; Leins, A.; Lellouch, D.; Letts, J.; Levinson, L.; Liebisch, R.; Lillich, J.; Littlewood, C.; Lloyd, A.W.; Lloyd, S.L.; Loebinger, F.K.; Long, G.D.; Losty, M.J.; Lu, J.; Ludwig, J.; Macchiolo, A.; Macpherson, A.; Mader, W.; Marcellini, S.; Marchant, T.E.; Martin, A.J.; Martin, J.P.; Martinez, G.; Mashimo, T.; Mattig, Peter; McDonald, W.John; McKenna, J.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Mendez-Lorenzo, P.; Menges, W.; Merritt, F.S.; Mes, H.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mohr, W.; Montanari, A.; Mori, T.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oakham, F.G.; Odorici, F.; Oh, A.; Okpara, A.; Oreglia, M.J.; Orito, S.; Pahl, C.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poli, B.; Polok, J.; Pooth, O.; Quadt, A.; Rabbertz, K.; Rembser, C.; Renkel, P.; Rick, H.; Rodning, N.; Roney, J.M.; Rosati, S.; Roscoe, K.; Rossi, A.M.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D.R.; Sachs, K.; Saeki, T.; Sahr, O.; Sarkisian, E.K.G.; Sbarra, C.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Siroli, G.P.; Skuja, A.; Smith, A.M.; Snow, G.A.; Sobie, R.; Soldner-Rembold, S.; Spagnolo, S.; Spano, F.; Sproston, M.; Stahl, A.; Stephens, K.; Strom, David M.; Strohmer, R.; Stumpf, L.; Surrow, B.; Talbot, S.D.; Tarem, S.; Tasevsky, M.; Taylor, R.J.; Teuscher, R.; Thomas, J.; Thomson, M.A.; Torrence, E.; Towers, S.; Toya, D.; Trefzger, T.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Vachon, B.; Vollmer, C.F.; Vannerem, P.; Verzocchi, M.; Voss, H.; Vossebeld, J.; Waller, D.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wengler, T.; Wermes, N.; Wetterling, D.; White, J.S.; Wilson, G.W.; Wilson, J.A.; Wyatt, T.R.; Yamashita, S.; Zacek, V.; Zer-Zion, D.

    2001-01-01

    Using data from e+e- annihilation into hadrons, taken with the OPAL detector at LEP at the Z pole between 1991 and 1995, we performed a simultaneous measurement of the colour factors of the underlying gauge group of the strong interaction, CF and CA, and the strong coupling, alpha(s). The measurement was carried out by fitting next-to-leading order perturbative predictions to measured angular correlations of 4-jet events together with multi-jet related variables. Our results, CA = 3.02 +/- 0.25 (stat.) +/- 0.49 (syst.) CF = 1.34 +/- 0.13 (stat.) +/- 0.22 (syst.), alpha(s)(M_Z) = 0.120 +/- 0.011 (stat.) +/- 0.020 (syst.), provide a test of perturbative QCD in which the only assumptions are non-abelian gauge symmetry and standard hadronization models. The measurements are in agreement with SU(3) expectations for CF and CA and the world average of alpha(s)(M_Z).

  1. Weighted least-square approach for simultaneous measurement of multiple reflective surfaces

    Tang, Shouhong; Bills, Richard E.; Freischlad, Klaus

    2007-09-01

    Phase shifting interferometry (PSI) is a highly accurate method for measuring the nanometer-scale relative surface height of a semi-reflective test surface. PSI is effectively used in conjunction with Fizeau interferometers for optical testing, hard disk inspection, and semiconductor wafer flatness. However, commonly-used PSI algorithms are unable to produce an accurate phase measurement if more than one reflective surface is present in the Fizeau interferometer test cavity. Examples of test parts that fall into this category include lithography mask blanks and their protective pellicles, and plane parallel optical beam splitters. The plane parallel surfaces of these parts generate multiple interferograms that are superimposed in the recording plane of the Fizeau interferometer. When using wavelength shifting in PSI the phase shifting speed of each interferogram is proportional to the optical path difference (OPD) between the two reflective surfaces. The proposed method is able to differentiate each underlying interferogram from each other in an optimal manner. In this paper, we present a method for simultaneously measuring the multiple test surfaces of all underlying interferograms from these superimposed interferograms through the use of a weighted least-square fitting technique. The theoretical analysis of weighted least-square technique and the measurement results will be described in this paper.

  2. Expanded beam deflection method for simultaneous measurement of displacement and vibrations of multiple microcantilevers

    Nieradka, K.; MaloziePc, G.; Kopiec, D.; Gotszalk, T.; Grabiec, P.; Janus, P.; Sierakowski, A.

    2011-01-01

    Here we present an extension of optical beam deflection (OBD) method for measuring displacement and vibrations of an array of microcantilevers. Instead of focusing on the cantilever, the optical beam is either focused above or below the cantilever array, or focused only in the axis parallel to the cantilevers length, allowing a wide optical line to span multiple cantilevers in the array. Each cantilever reflects a part of the incident beam, which is then directed onto a photodiode array detector in a manner allowing distinguishing between individual beams. Each part of reflected beam behaves like a single beam of roughly the same divergence angle in the bending sensing axis as the incident beam. Since sensitivity of the OBD method depends on the divergence angle of deflected beam, high sensitivity is preserved in proposed expanded beam deflection (EBD) method. At the detector, each spot's position is measured at the same time, without time multiplexing of light sources. This provides real simultaneous readout of entire array, unavailable in most of competitive methods, and thus increases time resolution of the measurement. Expanded beam can also span another line of cantilevers allowing monitoring of specially designed two-dimensional arrays. In this paper, we present first results of application of EBD method to cantilever sensors. We show how thermal noise resolution can be easily achieved and combined with thermal noise based resonance frequency measurement.

  3. Simultaneous viscosity and density measurement of small volumes of liquids using a vibrating microcantilever.

    Payam, A F; Trewby, W; Voïtchovsky, K

    2017-05-02

    Many industrial and technological applications require precise determination of the viscosity and density of liquids. Such measurements can be time consuming and often require sampling substantial amounts of the liquid. These problems can partly be overcome with the use of microcantilevers but most existing methods depend on the specific geometry and properties of the cantilever, which renders simple, accurate measurement difficult. Here we present a new approach able to simultaneously quantify both the density and the viscosity of microliters of liquids. The method, based solely on the measurement of two characteristic frequencies of an immersed microcantilever, is completely independent of the choice of a cantilever. We derive analytical expressions for the liquid's density and viscosity and validate our approach with several simple liquids and different cantilevers. Application of our model to non-Newtonian fluids shows that the calculated viscosities are remarkably robust when compared to measurements obtained from a standard rheometer. However, the results become increasingly dependent on the cantilever geometry as the frequency-dependent nature of the liquid's viscosity becomes more significant.

  4. Solid State Sensor for Simultaneous Measurement of Total Alkalinity and pH of Seawater.

    Briggs, Ellen M; Sandoval, Sergio; Erten, Ahmet; Takeshita, Yuichiro; Kummel, Andrew C; Martz, Todd R

    2017-09-22

    A novel design is demonstrated for a solid state, reagent-less sensor capable of rapid and simultaneous measurement of pH and Total Alkalinity (A T ) using ion sensitive field effect transistor (ISFET) technology to provide a simplified means of characterization of the aqueous carbon dioxide system through measurement of two "master variables": pH and A T . ISFET-based pH sensors that achieve 0.001 precision are widely used in various oceanographic applications. A modified ISFET is demonstrated to perform a nanoliter-scale acid-base titration of A T in under 40 s. This method of measuring A T , a Coulometric Diffusion Titration, involves electrolytic generation of titrant, H + , through the electrolysis of water on the surface of the chip via a microfabricated electrode eliminating the requirement of external reagents. Characterization has been performed in seawater as well as titrating individual components (i.e., OH - , HCO 3 - , CO 3 2- , B(OH) 4 - , PO 4 3- ) of seawater A T . The seawater measurements are consistent with the design in reaching the benchmark goal of 0.5% precision in A T over the range of seawater A T of ∼2200-2500 μmol kg -1 which demonstrates great potential for autonomous sensing.

  5. Determination of temperature dependant viscosity values of lubricants via simultaneous measurements of refractive index

    Yaltkaya, S.

    2005-01-01

    Viscosity is one of the most important parameter in rheological and tribological properties of fluids. The objective of this study is to obtain the viscosity values from the simultaneous refractive-index measurements of lubricants, simply by dipping the fiber-optic probe into the oil to be measured. Due to the fact that these parameters are temperature dependent, within the interval under consideration, oil heated up steadily while measuring the viscosity and refractive index at the same time. The refractive index sensor, the digital viscometer and the thermometer were connected to a PC via an analog to digital converter and the values were acquired at the same time. The fiber optic refractive index sensor has been designed in our laboratory. By utilising Fresnel's fundamental reflection law, the intensity of reflected light from boundary surface (optic fiber core-motor oil) was measured at 660 nm wavelength and then refractive index of the oil was calculated. The derived refractive index values were converted viscosity values that acquired by using the calibration equation. The viscometer, used during the study, was the rotational Brookfield type

  6. Simultaneous wall-shear-stress and wide-field PIV measurements in a turbulent boundary layer

    Gomit, Guillaume; Fourrie, Gregoire; de Kat, Roeland; Ganapathisubramani, Bharathram

    2015-11-01

    Simultaneous particle image velocimetry (PIV) and hot-film shear stress sensor measurements were performed to study the large-scale structures associated with shear stress events in a flat plate turbulent boundary layer at a high Reynolds number (Reτ ~ 4000). The PIV measurement was performed in a streamwise-wall normal plane using an array of six high resolution cameras (4 ×16MP and 2 ×29MP). The resulting field of view covers 8 δ (where δ is the boundary layer thickness) in the streamwise direction and captures the entire boundary layer in the wall-normal direction. The spatial resolution of the measurement is approximately is approximately 70 wall units (1.8 mm) and sampled each 35 wall units (0.9 mm). In association with the PIV setup, a spanwise array of 10 skin-friction sensors (spanning one δ) was used to capture the footprint of the large-scale structures. This combination of measurements allowed the analysis of the three-dimensional conditional structures in the boundary layer. Particularly, from conditional averages, the 3D organisation of the wall normal and streamwise velocity components (u and v) and the Reynolds shear stress (-u'v') related to a low and high shear stress events can be extracted. European Research Council Grant No-277472-WBT.

  7. Simultaneous rocket and radar measurements of currents in an auroral arc

    Robinson, R.M.; Bering, E.A.; Vondrak, R.R.; Anderson, H.R.; Cloutier, P.A.

    1981-01-01

    A detailed study of electric field, current and conductivities associated with an auroral arc was made in a coordinated rocket and radar experiment in Alaska on March 9, 1978. The payload, designated 29.007 UE, was launched at 1013 p.m. local time. It penetrated the diffuse aurora on the upleg and at apogee traversed field lines connected to a stable auroral arc of 40 kR intensity. Among the instruments carried by the payload were a vector magnetometer, a set of electrostatic double probes and a set of electron and proton spectrometers. Simultaneous electron density and line-of-sight velocity measurements were made by Chatanika radar operating in an elevation scan mode in the magnetic meridian plane. Both the radar and rocket measurements indicated that the zonal electric field was westward and approximately constant across the arc with a magnitude of about 7 mV/m. Small differences between the rocket and radar zonal electric field measurements indicated the presence of upward drifting ions in the region of the arc. The meridional field was large and northward equatorward of the arc, but negligible within the arc. Conductivities computed from measured fluxes of energetic electrons agreed well with the conductivities derived from the radar measureements of electron density. The electric field and conductivity measurements indicated that the zonal currents were eastward equatorward of the arc and westward within the arc. These electrojet currents agreed well with those inferred from the rocket magnetometer data. Better agreement was obtained when a westward neutral wind was added. The westward wind was also consistent with differences between the rocket and radar meridional electric fields. The meridional currents computed from the electric field measurements were northward over the entire region

  8. Simultaneous measurement of magnetic field and temperature based on an etched TCFMI cascaded with an FBG

    Yan, Guofeng; Zhang, Liang; He, Sailing

    2016-04-01

    In this paper, a dual-parameter measurement scheme based on an etched thin core fiber modal interferometer (TCMI) cascaded with a fiber Bragg grating (FBG) is proposed and experimentally demonstrated for simultaneous measurement of magnetic field and temperature. The magnetic field and temperature responses of the packaged TCFMI were first investigated, which showed that the magnetic field sensitivity could be highly enhanced by decreasing of the TCF diameter and the temperature-cross sensitivities were up to 3-7 Oe/°C at 1550 nm. Then, the theoretical analysis and experimental demonstration of the proposed dual-parameter sensing scheme were conducted. Experimental results show that, the reflection of the FBG has a magnetic field intensity and temperature sensitivities of -0.017 dB/Oe and 0.133 dB/°C, respectively, while the Bragg wavelength of the FBG is insensitive to magnetic field and has a temperature sensitivity of 13.23 pm/°C. Thus by using the sensing matrix method, the intensity of the magnetic field and the temperature variance can be measured, which enables magnetic field sensing under strict temperature environments. In the on-off time response test, the fabricated sensor exhibited high repeatability and short response time of ∼19.4 s. Meanwhile the reflective sensing probe type is more compact and practical for applications in hard-to-reach conditions.

  9. High resolution simultaneous measurements of airborne radionuclides in the pan-Japan sea area

    Yamaguchi, Y.; Abe, T.; Murata, Y.M.; Manikandan, N.; Tanaka, K.; Komura, K.

    2006-01-01

    By the use of ultra low background Ge detectors at Ogoya Underground Laboratory (OUL), it became possible to detect extremely low levels of environmental radionuclides. In this study, we tried to measure high resolution simultaneous measurements of airborne radionuclides at three monitoring points, i.e., 1) Low Level Radioactivity Laboratory (LLRL 40m asl) in Nomi City as the regular monitoring point, 2) Hegura Island Located 50 km from Noto Peninsula in the Sea of Japan to investigate the influence of Asian continent or mainland of Japan, and 3) Shishiku Plateau (640m asl) located about 8 km from LLRL to know vertical difference. Pb-210 and Be-7 were measured nondestructively by ultra low background gamma spectrometry at OUL, Po-210 by alpha spectrometry using Si detectors after the chemical treatment. Various interesting results on the concentrations and variation patterns of airborne radionuclides were obtained, particularly, during drastic meteorological changes such as the passage of typhoon, snow fall and so on. We have been analyzing the influence of the arrival of yellow sand occurred in this spring. (author)

  10. New Stereo Vision Digital Camera System for Simultaneous Measurement of Cloud Base Height and Atmospheric Visibility

    Janeiro, F. M.; Carretas, F.; Palma, N.; Ramos, P. M.; Wagner, F.

    2013-12-01

    Clouds play an important role in many aspects of everyday life. They affect both the local weather as well as the global climate and are an important parameter on climate change studies. Cloud parameters are also important for weather prediction models which make use of actual measurements. It is thus important to have low-cost instrumentation that can be deployed in the field to measure those parameters. This kind of instruments should also be automated and robust since they may be deployed in remote places and be subject to adverse weather conditions. Although clouds are very important in environmental systems, they are also an essential component of airplane safety when visual flight rules (VFR) are enforced, such as in most small aerodromes where it is not economically viable to install instruments for assisted flying. Under VFR there are strict limits on the height of the cloud base, cloud cover and atmospheric visibility that ensure the safety of the pilots and planes. Although there are instruments, available in the market, to measure those parameters, their relatively high cost makes them unavailable in many local aerodromes. In this work we present a new prototype which has been recently developed and deployed in a local aerodrome as proof of concept. It is composed by two digital cameras that capture photographs of the sky and allow the measurement of the cloud height from the parallax effect. The new developments consist on having a new geometry which allows the simultaneous measurement of cloud base height, wind speed at cloud base height and atmospheric visibility, which was not previously possible with only two cameras. The new orientation of the cameras comes at the cost of a more complex geometry to measure the cloud base height. The atmospheric visibility is calculated from the Lambert-Beer law after the measurement of the contrast between a set of dark objects and the background sky. The prototype includes the latest hardware developments that

  11. Simultaneous measurements of HF-enhanced plasma waves and artificial field-aligned irregularities at Arecibo

    Noble, S.T.; Djuth, F.T.

    1990-01-01

    Two radar systems with beams intersecting in the HF-modified F region were used to simultaneously measure HF-enhanced plasma lines (HFPLs) and artificial geomagnetic field-aligned irregularities (AFAIs). The Arecibo 430-MHz radar was used for the HFPL observations, and a portable 49.92-MHz backscatter radar was deployed on the island of Guadeloupe to monitor the AFAIs. The experiment was desgined to examine the degree to which HF-induced plasma turbulence influences the development of AFAIs. When the HF beam is stepped up in power, sustained HFPLs and AFAIs are first observed at the same HF power level, indicating that ponderomotively driven instabilities may be involved in the early time development of AFAIs. As the HF power is increased, the HFPL backscatter power begins to saturate at ∼70 MW effective radiated power (ERP). However, the backscatter from AFAIs is linearly dependent on HF power, even at the highest (120 MW ERP) HF power levels available at Arecibo. This suggests that additional processes may contribute to the development of AFAIs. For example, ponderomotively driven instabilities may give rise to weak geomagnetic field-aligned irregularities that are subsequently driven unstable by processes excited near the upper hybrid resonance. It is also likely that AFAIs greatly impact the development of HF-induced plasma turbulence at late times (>1 s) following HF turn-on. Once the ionosphere is preconditioned by high-power HF modifications, AFAIs and HFPLs can be simultaneously sustained at a much lower HF power level than that needed to originally excite them. The nature of the preconditioning process is currently not well understood. New theoretical initiatives are clearly needed to guide future experimental activity in this area

  12. What’s hampering measurement invariance: Detecting non-invariant items using clusterwise simultaneous component analysis

    Kim eDe Roover

    2014-06-01

    Full Text Available The issue of measurement invariance is ubiquitous in the behavioral sciences nowadays as more and more studies yield multivariate multigroup data. When measurement invariance cannot be established across groups, this is often due to different loadings on only a few items. Within the multigroup CFA framework, methods have been proposed to trace such non-invariant items, but these methods have some disadvantages in that they require researchers to run a multitude of analyses and in that they imply assumptions that are often questionable. In this paper, we propose an alternative strategy which builds on clusterwise simultaneous component analysis (SCA. Clusterwise SCA, being an exploratory technique, assigns the groups under study to a few clusters based on differences and similarities in the covariance matrices, and thus based on the component structure of the items. Non-invariant items can then be traced by comparing the cluster-specific component loadings via congruence coefficients, which is far more parsimonious than comparing the component structure of all separate groups. In this paper we present a heuristic for this procedure. Afterwards, one can return to the multigroup CFA framework and check whether removing the non-invariant items or removing some of the equality restrictions for these items, yields satisfactory invariance test results. An empirical application concerning cross-cultural emotion data is used to demonstrate that this novel approach is useful and can co-exist with the traditional CFA approaches.

  13. Simultaneous measurements of photoemission and morphology of various Al alloys during mechanical deformation

    Cai, M.; Li, W.; Dickinson, J. T.

    2006-11-01

    We report simultaneous measurements of strain and photoelectron emission from high purity Al (1350), Al-Mg (5052), Al-Mn (3003), Al-Cu (2024), and Al-Mg-Si (6061) alloys under uniaxial tension due to pulsed excimer laser radiation (248nm). The emission of low-energy photoelectrons is sensitive to deformation-induced changes in surface morphology, including the formation of slip lines and slip bands. Alloy composition and surface treatment significantly influence the photoemission during deformation. Surface oxide enhances the signal-to-noise level during photoemission measurement. In the early stage of deformation (strain ⩽0.04), photoemission intensity increases gradually in a nonlinear fashion. While subsequent photoemission increases almost linearly with strain until failure in samples with thin oxide layer (˜31Å), there are two linear segments of photoemission for the samples with oxide of 45Å. The onset of strain localization corresponds to the intersection point of two linear segments, usually at a strain of 0.08-0.20. A constitutive model incorporating microstructure evolution and work hardening during tensile deformation is proposed to qualitatively interpret the growth of the photoemission as a function of strain. Photoemissions from various alloys are interpreted in the light of surface treatment, work function, composition, and microstructural development during deformation.

  14. Simultaneous measurement of arginine vasopressin and oxytocin in plasma and neurohypophysis by radioimmunoassay

    Landgraf, R [Deutsche Hochschule fuer Koerperkultur, Leipzig (German Democratic Republic). Forschungsinstitut Koerperkultur und Sport

    1981-12-01

    Arginine vasopressin (AVP) and oxytocin (OXT) were measured simultaneously in the same sample by specific and sensitive radioimmunoassays (RIAs). The antibodies used did not cross-react to a variety of analogs and related peptides. The extraction procedure using Vycor glass powder resulted in mean recoveries of 84.4% (AVP) and 64.6% (OXT). In both assays, the sensitivity was 1 to 2 pg/ml plasma. A preincubation procedure that depresses plasma levels of both AVP and OXT selectively, provided specific blank values for a given plasma sample. To confirm the validity of the RIAs, dehydration experiments were performed. In rats, the basal levels of plasma AVP and OXT (means: 2,63 pg/ml and 6.80 pg/ml, respectively) are increased significantly after 24 h, 48 h and 72 h of water deprivation. Relationships are presented between both neurohormones in the plasma and neurohypophyses of control and dehydrated animals. As shown in cows, a significant correlation exists between plasma AVP and plasma osmolality but not between plasma OXT and osmolality or plasma AVP and OXT. Basal levels as well as physiological changes in plasma and neurohypophyseal AVP and OXT can be measured by the RIAs described.

  15. Simultaneous measurement of particle and fluid velocities in particle-laden flows

    Jin, D. X.; Lee, D. Y.

    2009-01-01

    For the velocity measurement in a particle-laden fluid flow, the fluid velocity and the inherently dispersed particle velocity can be analyzed by using PIV and PTV, respectively. Since the PIV result statistically represents the average displacement of all the particles in a PIV image, it is inevitable that the PIV result includes the influence of the dispersed particles' displacement if a single CCD camera is used to simultaneously measure the fluid velocity and the dispersed particle velocity. The influence of dispersed particles should be excluded before the PIV analysis in order to evaluate the fluid velocity accurately. In this study, the optimum replacement brightness of dispersed particles to minimize the false influence of dispersed particles on the PIV analysis was theoretically derived. Simulation results show that the modification of dispersed particle brightness can significantly reduce the PIV error caused by the dispersed particles. This modification method was also verified in the analysis of an actual experimental case of the particle-laden fluid flow in a triangular grooved channel

  16. Simultaneous measurements of reactive scalar and velocity in a planar liquid jet with a second-order chemical reaction

    Watanabe, Tomoaki; Sakai, Yasuhiko; Nagata, Kouji; Terashima, Osamu [Nagoya University, Department of Mechanical Science and Engineering, Nagoya (Japan); Kubo, Takashi [Meijo University, Faculty of Science and Technology, Nagoya (Japan)

    2012-11-15

    This paper presents a new experimental approach for simultaneous measurements of velocity and concentration in a turbulent liquid flow with a chemical reaction. For the simultaneous measurements, we developed a combined probe consisting of an I-type hot-film probe and an optical fiber probe based on the light absorption spectrometric method. In a turbulent planar liquid jet with a second-order chemical reaction (A+B{yields}R), streamwise velocity and concentrations of all reactive species are measured by the combined probe. The turbulent mass fluxes of the reactive species are estimated from the simultaneous measurements. The results show that the influence of the chemical reaction on the turbulent mass flux of the reactant species near the jet exit is different from its influence in other regions, and the turbulent mass flux of the product species has a negative value near the jet exit and a positive value in other regions. (orig.)

  17. Fiber Bragg Grating Measuring System for Simultaneous Monitoring of Temperature and Humidity in Mechanical Ventilation

    Carlo Massaroni

    2017-04-01

    Full Text Available During mechanical ventilation, the humidification of the dry air delivered by the mechanical ventilator is recommended. Among several solutions, heated wire humidifiers (HWHs have gained large acceptance to be used in this field. The aim of this work is to fabricate a measuring system based on fiber Bragg grating (FBG for the simultaneous monitoring of gas relative humidity (RH and temperature, intended to be used for providing feedback to the HWHs’ control. This solution can be implemented using an array of two FBGs having a different center wavelength. Regarding RH monitoring, three sensors have been fabricated by coating an FBG with two different moisture-sensitive and biocompatible materials: the first two sensors were fabricated by coating the grating with a 3 mm × 3 mm layer of agar and agarose; to investigate the influence of the coating thickness to the sensor response, a third sensor was developed with a 5 mm × 5 mm layer of agar. The sensors have been assessed in a wide range of RH (up to 95% during both an ascending and a subsequent descending phase. Only the response of the 3 mm × 3 mm-coated sensors were fast enough to follow the RH changes, showing a mean sensitivity of about 0.14 nm/% (agar-coated and 0.12 nm/% (agarose-coated. The hysteresis error was about <10% in the two sensors. The contribution of temperature changes on these RH sensors was negligible. The temperature measurement was performed by a commercial FBG insensitive to RH changes. The small size of these FBG-based sensors, the use of biocompatible polymers, and the possibility to measure both temperature and RH by using the same fiber optic embedding an array of two FBGs make intriguing the use of this solution for application in the control of HWHs.

  18. Multi-spacecraft observations of solar hard X-ray bursts

    Kane, S.R.

    1981-01-01

    The role of multi-spacecraft observations in solar flare research is examined from the point of view of solar hard X-ray bursts and their implications with respect to models of the impulsive phase. Multi-spacecraft measurements provide a stereoscopic view of the flare region, and hence represent the only direct method of measuring directivity of X-rays. In absence of hard X-ray imaging instruments with high spatial and temporal resolution, multi-spacecraft measurements provide the only means of determining the radial (vertical) structure of the hard X-ray source. This potential of the multi-spacecraft observations is illustrated with an analysis of the presently available observations of solar hard X-ray bursts made simultaneously by two or more of the following spacecraft: International Sun Earth Explorer-3 (ISEE-3), Pioneer Venus Orbiter (PVO), Helios-B and High Energy Astrophysical Observatory-A (HEAO-A). In particular, some conclusions have been drawn about the spatial structure and directivity of 50-100 keV X-rays from impulsive flares. Desirable features of future multi-spacecraft missions are briefly discussed followed by a short description of the hard X-ray experiment on the International Solar Polar Mission which has been planned specifically for multi-spacecraft observations of the Sun. (orig.)

  19. Nearly simultaneous measurements of radar auroral heights and Doppler velocities at 398 MHz

    Moorcroft, D.; Ruohoniemi, J.M.

    1987-01-01

    Nearly simultaneous measurements of radar auroral heights and Doppler velocities were obtained using the Homer, Alaska, 398-MHz phased-array radar over a total of 16 hours on four different days. The heights show a consistent variation with time, being highest near the time of electrojet current reversal, and lowest late in the morning. A variety of east-west height asymmetries were observed, different from those previously reported, which can be explained in terms of favorable flow angles preferentially favoring high-altitude primary two-stream waves to one side of the field of view. Low-velocity echoes, presumably due to secondary irregularities, are found to be more restricted in height range than echoes with ion acoustic velocities, which presumably come from primary two-stream instabilities. Echo power was examined as a function of velocity and height. For the westward electrojet it was found that echoes with ion acoustic velocities are relatively constant in strength over most of their height range, but for low-velocity echoes the power is a maximum between 100 and 105 km and falls off steadily at greater heights. Doppler speeds show a noticeable decrease at heights below 105 km, in agreement with the expected variation in ion acoustic velocity

  20. Simultaneous measurement of strain, temperature and refractive index based on multimode interference, fiber tapering and fiber Bragg gratings

    Oliveira, Ricardo; Osório, Jonas H; Aristilde, Stenio; Cordeiro, Cristiano M B; Bilro, Lúcia; Nogueira, Rogerio N

    2016-01-01

    We report the development of an optical fiber sensor capable of simultaneously measuring strain, temperature and refractive index. The sensor is based on the combination of two fiber Bragg gratings written in a standard single-mode fiber, one in an untapered region and another in a tapered region, spliced to a no-core fiber. The possibility of simultaneously measuring three parameters relies on the different sensitivity responses of each part of the sensor. The results have shown the possibility of measuring three parameters simultaneously with a resolution of 3.77 με , 1.36 °C and 5  ×  10 −4 , respectively for strain, temperature and refractive index. On top of the multiparameter ability, the simple production and combination of all the parts involved on this optical-fiber-based sensor is an attractive feature for several sensing applications. (paper)

  1. Spacecraft radiator systems

    Anderson, Grant A. (Inventor)

    2012-01-01

    A spacecraft radiator system designed to provide structural support to the spacecraft. Structural support is provided by the geometric "crescent" form of the panels of the spacecraft radiator. This integration of radiator and structural support provides spacecraft with a semi-monocoque design.

  2. FIRST MEASUREMENTS OF THE MASS OF CORONAL MASS EJECTIONS FROM THE EUV DIMMING OBSERVED WITH STEREO EUVI A+B SPACECRAFT

    Aschwanden, Markus J.; Nitta, Nariaki V.; Wuelser, Jean-Pierre; Lemen, James R.; Sandman, Anne; Vourlidas, Angelos; Colaninno, Robin C.

    2009-01-01

    The masses of coronal mass ejections (CMEs) have traditionally been determined from white-light coronagraphs (based on Thomson scattering of electrons), as well as from extreme ultraviolet (EUV) dimming observed with one spacecraft. Here we develop an improved method of measuring CME masses based on EUV dimming observed with the dual STEREO/EUVI spacecraft in multiple temperature filters that includes three-dimensional volume and density modeling in the dimming region and background corona. As a test, we investigate eight CME events with previous mass determinations from STEREO/COR2, of which six cases are reliably detected with the Extreme Ultraviolet Imager (EUVI) using our automated multi-wavelength detection code. We find CME masses in the range of m CME = (2-7) x 10 15 g. The agreement between the two EUVI/A and B spacecraft is m A /m B = 1.3 ± 0.6 and the consistency with white-light measurements by COR2 is m EUVI /m COR2 = 1.1 ± 0.3. The consistency between EUVI and COR2 implies no significant mass backflows (or inflows) at r sun and adequate temperature coverage for the bulk of the CME mass in the range of T ∼ 0.5-3.0 MK. The temporal evolution of the EUV dimming allows us to also model the evolution of the CME density n e (t), volume V(t), height-time h(t), and propagation speed v(t) in terms of an adiabatically expanding self-similar geometry. We determine e-folding EUV dimming times of t D = 1.3 ± 1.4 hr. We test the adiabatic expansion model in terms of the predicted detection delay (Δt ∼ 0.7 hr) between EUVI and COR2 for the fastest CME event (2008 March 25) and find good agreement with the observed delay (Δt ∼ 0.8 hr).

  3. Measurement of neurovascular coupling in human motor cortex using simultaneous transcranial doppler (TCD) and electroencephalography (EEG).

    Alam, Monzurul; Ahmed, Ghazanfar; Ling, Yan To; Zheng, Yong-Ping

    2018-05-25

    Event-related desynchronization (ERD) is a relative power decrease of electroencephalogram (EEG) signals in a specific frequency band during physical motor execution, while transcranial Doppler (TCD) measures cerebral blood flow velocity. The objective of this study was to investigate the neurovascular coupling in the motor cortex by using an integrated EEG and TCD system, and to find any difference in hemodynamic responses in healthy young male and female adults. Approach: 30 healthy volunteers, aged 20-30 years were recruited for this study. The subjects were asked to perform a motor task for the duration of a provided visual cue. Simultaneous EEG and TCD recording was carried out using a new integrated system to detect the ERD arising from the EEG signals, and to measure the mean blood flow velocity of the left and right middle cerebral arteries from bilateral TCD signals. Main Results: The results showed a significant decrease in EEG power in mu band (7.5-12.5 Hz) during the motor task compared to the resting phase. It showed significant increase in desynchronization on the contralateral side of the motor task compared to the ipsilateral side. Mean blood flow velocity during the task phase was significantly higher in comparison with the resting phase at the contralateral side. The results also showed a significantly higher increase in the percentage of mean blood flow velocity in the contralateral side of motor task compared to the ipsilateral side. However, no significant difference in desynchronization, or change of mean blood flow velocity was found between males and females. Significance: A combined TCD-EEG system successfully detects ERD and blood flow velocity in cerebral arteries, and can be used as a useful tool to study neurovascular coupling in the brain. There is no significant difference in the hemodynamic responses in healthy young males and females. © 2018 Institute of Physics and Engineering in Medicine.

  4. Spacecraft Jitter Attenuation Using Embedded Piezoelectric Actuators

    Belvin, W. Keith

    1995-01-01

    Remote sensing from spacecraft requires precise pointing of measurement devices in order to achieve adequate spatial resolution. Unfortunately, various spacecraft disturbances induce vibrational jitter in the remote sensing instruments. The NASA Langley Research Center has performed analysis, simulations, and ground tests to identify the more promising technologies for minimizing spacecraft pointing jitter. These studies have shown that the use of smart materials to reduce spacecraft jitter is an excellent match between a maturing technology and an operational need. This paper describes the use of embedding piezoelectric actuators for vibration control and payload isolation. In addition, recent advances in modeling, simulation, and testing of spacecraft pointing jitter are discussed.

  5. Multiwavelength Raman-fiber-laser-based long-distance remote sensor for simultaneous measurement of strain and temperature.

    Han, Young-Geun; Tran, T V A; Kim, Sang-Hyuck; Lee, Sang Bae

    2005-06-01

    We propose a simple and flexible multiwavelength Raman-fiber-laser-based long-distance remote-sensing scheme for simultaneous measurement of strain and temperature by use of fiber Bragg gratings. By combining two uniform fiber Bragg gratings with a tunable chirped fiber grating, we readily achieve simultaneous two-channel sensing probes with a high extinction ratio of more than approximately 50 dB over a 50-km distance. When strain and temperature are applied, lasing wavelength separation and shift occur, respectively, since the two uniform fiber Bragg gratings have identical material composition and different cladding diameters. This allows simultaneous measurement of strain and temperature for long-distance sensing applications of more than 50 km.

  6. Simultaneous measurement of aurora-related, irregular magnetic pulsations at northern and southern high latitudes

    Arnoldy, R.L.; Rajashekar, R.; Cahill, L.J. Jr.; Engebretson, M.J.; Rosenberg, T.J.; Mende, S.B.

    1987-01-01

    A dominant feature of high-latitude magnetic pulsations is large-amplitude irregular pulsations (Pi) which are closely correlated with the movement of the observing station under particle precipitation, producing the dayside auroral and the high-latitude expansion of nightside aurora. The dayside Pi-1 pulsation maximum centered about local magnetic noon has no strong seasonal dependence, indicating that the dayside aurora illuminates both hemispheres independent of the latitude of the subsolar point. The summer noon pulsation maximum has, however, a greater longitudinal extent than the winter noon maximum, as measured at 74 degree-75 degree invariant latitude. The nightside magnetic pulsations are bursts of Pi (PiB) having an average duration of 15 min. From Defense Meteorological Satellite Program photos the auroral forms related to the high-latitude PiB can be identified as the poleward discrete arc generally having a large longitudinal extent. If the auroral forms are very similar in both hemispheres, then the large longitudinal extent coupled with movement of the auroral could explain why 85% of the PiB events have onsets within 10 min at opposite hemisphere sites (South Pole, Antarctica, and Sondre Stromfjord, Greenland) separated in local magnetic time by about 1.5 hours. There is no seasonal dependence in the statistical occurrence of PiB, nor in its simultaneity in opposite hemispheres. Apparently, the seasonal distortion of the tail plasma sheet has little effect on the acceleration of high-latitude auroral beams. The actual several minute time difference in opposite hemisphere onsets of PiB is probably due to the westward/poleward motion of the longitudinally extended aurora

  7. Simultaneous Investigation of Sediment Transport and Water Quality Parameters Using An In Situ Measurement Device

    Prochnow, J. V.

    Though quality of surface waters has improved remarkably over the last twenty years, the contaminant load of soft cohesive sediments remained comparatively unimproved. That is why the new European water framework directive addresses contaminant loaded sediments and postulates criteria for assessing sediment quality. Surveys into contaminated sediment behaviour have revealed adsorption/desorption characteristics of individual toxins. Biomonitoring of pollutant pressure on specific benthic organ- isms on the other hand can be useful to elucidate potential dangers to aquatic ecosys- tems. However, it is yet unknown how a given contaminant loaded sediment will re- spond to different hypercritical flow conditions in terms of release rates and partition- ing of xenobiotica. On this account a small in situ measuring device (EROSIMESS) was constructed, that features simultaneous determination of suspended sediment con- centration (optical turbidity meter), dissolved oxygen levels, pH and temperature (membrane probes) under predefined hydraulic conditions. Samples of the suspen- sion can be withdrawn for subsequent chemical analysis. Bottom shear stresses up to 5N/m2 can be generated by means of a propeller that resides in cylindrical perspex tube (erosion chamber) two centimeters above the sediment bed. Baffles on the in- ner wall of the cylinder prevent a solid body rotation of the suspension by creating additional turbulence and a second propeller straight beneath the concentration me- ter inhibits the development of a concentration gradient within the chamber. A small CCD-camera is used to control positioning of the device. It can be used in water- depths up to 5m. The control unit consists of a trigger box and an ordinary laptop computer running LabView. EROSIMESS has been successfully used in various stud- ies on contaminant release, eutrophication, and SOD (sediment oxygen demand) in rivers (Spree: Germany; Maun: UK), reservoirs (Heimbach, Haus Ley: Germany), and

  8. Urethral pressure reflectometry. A method for simultaneous measurements of pressure and cross-sectional area in the female urethra

    Klarskov, Niels

    2012-01-01

    A novel technique for simultaneous measurements of pressure and cross-sectional area (CA) in the female urethra, denoted Urethral Pressure Reflectometry (UPR), was devised. A very thin and highly flexible polyurethane-bag was placed in the urethra. A pump applied increasing and decreasing pressur...

  9. Spacecraft Charging and the Microwave Anisotropy Probe Spacecraft

    Timothy, VanSant J.; Neergaard, Linda F.

    1998-01-01

    The Microwave Anisotropy Probe (MAP), a MIDEX mission built in partnership between Princeton University and the NASA Goddard Space Flight Center (GSFC), will study the cosmic microwave background. It will be inserted into a highly elliptical earth orbit for several weeks and then use a lunar gravity assist to orbit around the second Lagrangian point (L2), 1.5 million kilometers, anti-sunward from the earth. The charging environment for the phasing loops and at L2 was evaluated. There is a limited set of data for L2; the GEOTAIL spacecraft measured relatively low spacecraft potentials (approx. 50 V maximum) near L2. The main area of concern for charging on the MAP spacecraft is the well-established threat posed by the "geosynchronous region" between 6-10 Re. The launch in the autumn of 2000 will coincide with the falling of the solar maximum, a period when the likelihood of a substorm is higher than usual. The likelihood of a substorm at that time has been roughly estimated to be on the order of 20% for a typical MAP mission profile. Because of the possibility of spacecraft charging, a requirement for conductive spacecraft surfaces was established early in the program. Subsequent NASCAP/GEO analyses for the MAP spacecraft demonstrated that a significant portion of the sunlit surface (solar cell cover glass and sunshade) could have nonconductive surfaces without significantly raising differential charging. The need for conductive materials on surfaces continually in eclipse has also been reinforced by NASCAP analyses.

  10. Simultaneous measurement of field dependence of elastic moduli by laser interferometry

    Bayon, A; Salazar, F

    2000-01-01

    A methodology is applied which allows the simultaneous determination of Young's modulus and the shear modulus to evaluate elastic moduli variations with the magnetic field (DELTA E and DELTA G). The method employed is based on the simultaneous detection of the transverse and torsional natural frequencies of a slender magnetic bar located within a solenoid. The resultant vibration is detected via a heterodyne interferometric optical system with a broad bandwidth. The vibration detection and excitation systems do not interact with the sample. The applicability of the method is demonstrated by characterizing 10-mm-diameter nickel bars. The results are compared with those obtained from longitudinal vibrations.

  11. Constraints on Ceres' Internal Structure and Evolution From Its Shape and Gravity Measured by the Dawn Spacecraft

    Ermakov, A. I.; Fu, R. R.; Castillo-Rogez, J. C.; Raymond, C. A.; Park, R. S.; Preusker, F.; Russell, C. T.; Smith, D. E.; Zuber, M. T.

    2017-11-01

    Ceres is the largest body in the asteroid belt with a radius of approximately 470 km. In part due to its large mass, Ceres more closely approaches hydrostatic equilibrium than major asteroids. Pre-Dawn mission shape observations of Ceres revealed a shape consistent with a hydrostatic ellipsoid of revolution. The Dawn spacecraft Framing Camera has been imaging Ceres since March 2015, which has led to high-resolution shape models of the dwarf planet, while the gravity field has been globally determined to a spherical harmonic degree 14 (equivalent to a spatial wavelength of 211 km) and locally to 18 (a wavelength of 164 km). We use these shape and gravity models to constrain Ceres' internal structure. We find a negative correlation and admittance between topography and gravity at degree 2 and order 2. Low admittances between spherical harmonic degrees 3 and 16 are well explained by Airy isostatic compensation mechanism. Different models of isostasy give crustal densities between 1,200 and 1,400 kg/m3 with our preferred model giving a crustal density of 1,287+70-87 kg/m3. The mantle density is constrained to be 2,434+5-8 kg/m3. We compute isostatic gravity anomaly and find evidence for mascon-like structures in the two biggest basins. The topographic power spectrum of Ceres and its latitude dependence suggest that viscous relaxation occurred at the long wavelengths (>246 km). Our density constraints combined with finite element modeling of viscous relaxation suggests that the rheology and density of the shallow surface are most consistent with a rock, ice, salt and clathrate mixture.

  12. Simultaneous interferometric measurement of linear coefficient of thermal expansion and temperature-dependent refractive index coefficient of optical materials.

    Corsetti, James A; Green, William E; Ellis, Jonathan D; Schmidt, Greg R; Moore, Duncan T

    2016-10-10

    Characterizing the thermal properties of optical materials is necessary for understanding how to design an optical system for changing environmental conditions. A method is presented for simultaneously measuring both the linear coefficient of thermal expansion and the temperature-dependent refractive index coefficient of a sample interferometrically in air. Both the design and fabrication of the interferometer is presented as well as a discussion of the results of measuring both a steel and a CaF2 sample.

  13. Simultaneous measurement of refractive index and thickness distributions using low-coherence digital holography and vertical scanning

    Watanabe, Kaho; Ohshima, Masashi; Nomura, Takanori

    2014-01-01

    The simultaneous measurement method of a refractive index distribution and a thickness distribution using low-coherence digital holography with a vertical scanning is proposed. The proposed method consists of a combination of digital holography and low-coherence interferometry. The introduction of a datum plane enables the measurement of both a refractive index distribution and a thickness distribution. By the optical experiment, the potential of the proposed method is confirmed. (paper)

  14. Visual measurement of the evaporation process of a sessile droplet by dual-channel simultaneous phase-shifting interferometry.

    Sun, Peng; Zhong, Liyun; Luo, Chunshu; Niu, Wenhu; Lu, Xiaoxu

    2015-07-16

    To perform the visual measurement of the evaporation process of a sessile droplet, a dual-channel simultaneous phase-shifting interferometry (DCSPSI) method is proposed. Based on polarization components to simultaneously generate a pair of orthogonal interferograms with the phase shifts of π/2, the real-time phase of a dynamic process can be retrieved with two-step phase-shifting algorithm. Using this proposed DCSPSI system, the transient mass (TM) of the evaporation process of a sessile droplet with different initial mass were presented through measuring the real-time 3D shape of a droplet. Moreover, the mass flux density (MFD) of the evaporating droplet and its regional distribution were also calculated and analyzed. The experimental results show that the proposed DCSPSI will supply a visual, accurate, noncontact, nondestructive, global tool for the real-time multi-parameter measurement of the droplet evaporation.

  15. Simultaneous measurement of temperature and strain using a phase-shifted fiber Bragg grating inscribed by femtosecond laser

    Jiang, Yajun; Liu, Chi; Li, Dong; Yang, Dexing; Zhao, Jianlin

    2018-04-01

    A novel method for simultaneous measurement of temperature and strain using a single phase-shifted fiber Bragg grating (PS-FBG) is proposed. The PS-FBG is produced by exposing the fusion-spliced fiber with a femtosecond laser and uniform phase mask. Due to the non-uniform structure and strain distribution in the fusion-spliced region, the phase-shift changes with different responses during increases to the temperature and strain; by measuring the central wavelengths and the loss difference of two transmission dips, temperature and strain can be determined simultaneously. The resolutions of this particular sensor in measuring temperature and strain are estimated to be  ±1.5 °C and  ±12.2 µɛ in a range from  -50 °C to 150 °C and from 0 µɛ to 2070 µɛ.

  16. Test-retest measurements of dopamine D_1-type receptors using simultaneous PET/MRI imaging

    Kaller, Simon; Patt, Marianne; Becker, Georg-Alexander; Luthardt, Julia; Meyer, Philipp M.; Werner, Peter; Barthel, Henryk; Bresch, Anke; Sabri, Osama; Rullmann, Michael; Girbardt, Johanna; Fritz, Thomas H.; Hesse, Swen

    2017-01-01

    The role of dopamine D_1-type receptor (D_1R)-expressing neurons in the regulation of motivated behavior and reward prediction has not yet been fully established. As a prerequisite for future research assessing D_1-mediated neuronal network regulation using simultaneous PET/MRI and D_1R-selective ["1"1C]SCH23390, this study investigated the stability of central D_1R measurements between two independent PET/MRI sessions under baseline conditions. Thirteen healthy volunteers (7 female, age 33 ± 13 yrs) underwent 90-min emission scans, each after 90-s bolus injection of 486 ± 16 MBq ["1"1C]SCH23390, on two separate days within 2-4 weeks using a PET/MRI system. Parametric images of D_1R distribution volume ratio (DVR) and binding potential (BP_N_D) were generated by a multi-linear reference tissue model with two parameters and the cerebellar cortex as receptor-free reference region. Volume-of-interest (VOI) analysis was performed with manual VOIs drawn on consecutive transverse MRI slices for brain regions with high and low D_1R density. The DVR varied from 2.5 ± 0.3 to 2.9 ± 0.5 in regions with high D_1R density (e.g. the head of the caudate) and from 1.2 ± 0.1 to 1.6 ± 0.2 in regions with low D_1R density (e.g. the prefrontal cortex). The absolute variability of the DVR ranged from 2.4% ± 1.3% to 5.1% ± 5.3%, while Bland-Altman analyses revealed very low differences in mean DVR (e.g. 0.013 ± 0.17 for the nucleus accumbens). Intraclass correlation (one-way, random) indicated very high agreement (0.93 in average) for both DVR and BP_N_D values. Accordingly, the absolute variability of BP_N_D ranged from 7.0% ± 4.7% to 12.5% ± 10.6%; however, there were regions with very low D_1R content, such as the occipital cortex, with higher mean variability. The test-retest reliability of D_1R measurements in this study was very high. This was the case not only for D_1R-rich brain areas, but also for regions with low D_1R density. These results will provide a solid base

  17. A five-collector system for the simultaneous measurement of argon isotope ratios in a static mass spectrometer

    Stacey, J.S.; Sherrill, N.D.; Dalrymple, G.B.; Lanphere, M.A.; Carpenter, N.V.

    1981-01-01

    A system is described that utilizes five separate Faraday-cup collector assemblies, aligned along the focal plane of a mass spectrometer, to collect simultaneous argon ion beams at masses 36-40. Each collector has its own electrometer amplifier and analog-to-digital measuring channel, the outputs of which are processed by a minicomputer that also controls the mass spectrometer. The mass spectrometer utilizes a 90?? sector magnetic analyzer with a radius of 23 cm, in which some degree of z-direction focussing is provided for all the ion beams by the fringe field of the magnet. Simultaneous measurement of the ion beams helps to eliminate mass-spectrometer memory as a significant source of measurement error during an analysis. Isotope ratios stabilize between 7 and 9 s after sample admission into the spectrometer, and thereafter changes in the measured ratios are linear, typically to within ??0.02%. Thus the multi-collector arrangement permits very short extrapolation times for computation of initial ratios, and also provides the advantages of simultaneous measurement of the ion currents in that errors due to variations in ion beam intensity are minimized. A complete analysis takes less than 10 min, so that sample throughput can be greatly enhanced. In this instrument, the factor limiting analytical precision now lies in short-term apparent variations in the interchannel calibration factors. ?? 1981.

  18. Simultaneous pressure-volume measurements using optical sensors and MRI for left ventricle function assessment during animal experiment.

    Abi-Abdallah Rodriguez, Dima; Durand, Emmanuel; de Rochefort, Ludovic; Boudjemline, Younes; Mousseaux, Elie

    2015-01-01

    Simultaneous pressure and volume measurements enable the extraction of valuable parameters for left ventricle function assessment. Cardiac MR has proven to be the most accurate method for volume estimation. Nonetheless, measuring pressure simultaneously during MRI acquisitions remains a challenge given the magnetic nature of the widely used pressure transducers. In this study we show the feasibility of simultaneous in vivo pressure-volume acquisitions with MRI using optical pressure sensors. Pressure-volume loops were calculated while inducing three inotropic states in a sheep and functional indices were extracted, using single beat loops, to characterize systolic and diastolic performance. Functional indices evolved as expected in response to positive inotropic stimuli. The end-systolic elastance, representing the contractility index, the diastolic myocardium compliance, and the cardiac work efficiency all increased when inducing inotropic state enhancement. The association of MRI and optical pressure sensors within the left ventricle successfully enabled pressure-volume loop analysis after having respective data simultaneously recorded during the experimentation without the need to move the animal between each inotropic state. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

  19. Comparison of eye-safe solid state laser DIAL with passive gas filter correlation measurements from aircraft and spacecraft

    Hess, Robert V.; Staton, Leo D.; Wallio, H. Andrew; Wang, Liang-Guo

    1992-01-01

    Differential Absorption Lidar (DIAL) using solid state Ti:sapphire lasers finds current application in the NASA/LASE Project for H2O vapor measurements in the approximately = 0.820 micron region for the lower and mid-troposphere and in potential future applications in planned measurements of the approximately = 0.940 micron region where both strong and weak absorption lines enables measurements throughout the troposphere and lower stratosphere. The challenge exists to perform measurements in the eye-safe greater than 1.5 micron region. A comparison between DIAL and passive Gas Filter Correlation Radiometer (GFCR) measurements is made. The essence of the differences in signal to noise ratio for DIAL and passive GFCR measurements is examined. The state of the art of lasers and optical parametric oscillators (OPO's) is discussed.

  20. PET Imaging Stability Measurements During Simultaneous Pulsing of Aggressive MR Sequences on the SIGNA PET/MR System.

    Deller, Timothy W; Khalighi, Mohammad Mehdi; Jansen, Floris P; Glover, Gary H

    2018-01-01

    The recent introduction of simultaneous whole-body PET/MR scanners has enabled new research taking advantage of the complementary information obtainable with PET and MRI. One such application is kinetic modeling, which requires high levels of PET quantitative stability. To accomplish the required PET stability levels, the PET subsystem must be sufficiently isolated from the effects of MR activity. Performance measurements have previously been published, demonstrating sufficient PET stability in the presence of MR pulsing for typical clinical use; however, PET stability during radiofrequency (RF)-intensive and gradient-intensive sequences has not previously been evaluated for a clinical whole-body scanner. In this work, PET stability of the GE SIGNA PET/MR was examined during simultaneous scanning of aggressive MR pulse sequences. Methods: PET performance tests were acquired with MR idle and during simultaneous MR pulsing. Recent system improvements mitigating RF interference and gain variation were used. A fast recovery fast spin echo MR sequence was selected for high RF power, and an echo planar imaging sequence was selected for its high heat-inducing gradients. Measurements were performed to determine PET stability under varying MR conditions using the following metrics: sensitivity, scatter fraction, contrast recovery, uniformity, count rate performance, and image quantitation. A final PET quantitative stability assessment for simultaneous PET scanning during functional MRI studies was performed with a spiral in-and-out gradient echo sequence. Results: Quantitation stability of a 68 Ge flood phantom was demonstrated within 0.34%. Normalized sensitivity was stable during simultaneous scanning within 0.3%. Scatter fraction measured with a 68 Ge line source in the scatter phantom was stable within the range of 40.4%-40.6%. Contrast recovery and uniformity were comparable for PET images acquired simultaneously with multiple MR conditions. Peak noise equivalent count

  1. Entrainment and mixing in lock-exchange gravity currents using simultaneous velocity-density measurements

    Balasubramanian, Sridhar; Zhong, Qiang

    2018-05-01

    Gravity currents modify their flow characteristics by entraining ambient fluid, which depends on a variety of governing parameters such as the initial density, Δρ, the total initial height of the fluid, H, and the slope of the terrain, α, from where it is released. It is imperative to study the entrainment dynamics of a gravity current in order to have a clear understanding of mixing transitions that govern the flow physics, the velocity mixing layer thickness, δu, and the density mixing layer thickness, δρ. Experiments were conducted in a lock-exchange facility in which the dense fluid was separated from the ambient lighter fluid using a gate. As the gate is released instantaneously, an energy conserving gravity current is formed, for which the only governing parameter is the Reynolds number defined as R e =U/h ν , where U is the front velocity of the gravity current and h is the height of the current. In our study, the bulk Richardson number (inverse of Froude number, Fr), Rib = g/'H Ub2 = 1, takes a constant value for all the experiments, with Ub being the bulk velocity of the current defined as Ub = √{g'H }. Simultaneous particle image velocimetry and planar laser induced fluorescence measurement techniques are employed to get the velocity and density statistics. Using the buoyancy conservation equation, a new flux-based method was formulated for calculating the entrainment coefficient, EF, near the front and head of the propagating gravity current for a Reynolds number range of Re ≈ 485-12 270 used in our experiments. At the head of the current, the results show a mixing transition at Re ≈ 2700 that is attributed to the flow transitioning from weak Holmboe waves to Kelvin-Helmholtz instabilities, in the form of Kelvin-Helmholtz vortex rolls. Following this mixing transition, the entrainment coefficient continued to increase with increasing Reynolds number owing to the occurrence of three-dimensional Kelvin-Helmholtz billows that promote further

  2. Modeling and Simulation of Satellite Subsystems for End-to-End Spacecraft Modeling

    Schum, William K; Doolittle, Christina M; Boyarko, George A

    2006-01-01

    During the past ten years, the Air Force Research Laboratory (AFRL) has been simultaneously developing high-fidelity spacecraft payload models as well as a robust distributed simulation environment for modeling spacecraft subsystems...

  3. Simultaneous measurement of temperature and pressure by a single fiber Bragg grating with a broadened reflection spectrum.

    Guo, Tuan; Qiao, Xueguang; Jia, Zhenan; Zhao, Qida; Dong, Xiaoyi

    2006-05-01

    Simultaneous measurement of temperature and pressure with a single fiber Bragg grating (FBG) based on a broadened reflection spectrum is proposed and experimentally demonstrated. A novel double-hole structure of a cantilever beam is designed, and a FBG is affixed on the nonuniform strain area of the cantilever beam. The Bragg reflection bandwidth is sensitive to the spatially gradient strain but is free from the spatially uniform temperature. The wavelength peak shift and the bandwidth broadening of the FBG with a change of temperature and pressure allow for simultaneous discrimination between the temperature and the pressure effects. Standard deviation errors of 1.4 degrees C and 1.8 kPa were obtained with temperature and pressure ranges of 20 degrees C-100 degrees C and 0-80 kPa, respectively. This novel and low-cost sensor approach has considerable potential applications for temperature-insensitive strain measurement.

  4. Development of a simple system for simultaneously measuring 6DOF geometric motion errors of a linear guide.

    Qibo, Feng; Bin, Zhang; Cunxing, Cui; Cuifang, Kuang; Yusheng, Zhai; Fenglin, You

    2013-11-04

    A simple method for simultaneously measuring the 6DOF geometric motion errors of the linear guide was proposed. The mechanisms for measuring straightness and angular errors and for enhancing their resolution are described in detail. A common-path method for measuring the laser beam drift was proposed and it was used to compensate the errors produced by the laser beam drift in the 6DOF geometric error measurements. A compact 6DOF system was built. Calibration experiments with certain standard measurement meters showed that our system has a standard deviation of 0.5 µm in a range of ± 100 µm for the straightness measurements, and standard deviations of 0.5", 0.5", and 1.0" in the range of ± 100" for pitch, yaw, and roll measurements, respectively.

  5. A microfluidic device for simultaneous measurement of viscosity and flow rate of blood in a complex fluidic network

    Jun Kang, Yang; Yeom, Eunseop; Lee, Sang-Joon

    2013-01-01

    Blood viscosity has been considered as one of important biophysical parameters for effectively monitoring variations in physiological and pathological conditions of circulatory disorders. Standard previous methods make it difficult to evaluate variations of blood viscosity under cardiopulmonary bypass procedures or hemodialysis. In this study, we proposed a unique microfluidic device for simultaneously measuring viscosity and flow rate of whole blood circulating in a complex fluidic network i...

  6. A coincidence method for the simultaneous measurement of the photoionization of several masses

    Broeker, G.

    1989-11-01

    This study was made in the working team Ding (Hahn-Meitner Institute Berlin) in the framework of photoionization experiments on Van-der-Waals clusters. The experiments were performed at the Berlin electron storage ring (BESSY). In a molecular-beam source clusters are produced and ionized by monochromatic light. The mass of the ions arising hereby is determined with a time-of-flight mass spectrometer. Within this thesis a method and an electronic device was developed, by which it is made possible to gather simultaneously the wave-length dependence of several masses. (orig.) With 27 refs [de

  7. Omnidirectional angle constraint based dynamic six-degree-of-freedom measurement for spacecraft rendezvous and docking simulation

    Shi, Shendong; Yang, Linghui; Lin, Jiarui; Ren, Yongjie; Guo, Siyang; Zhu, Jigui

    2018-04-01

    In this paper we present a novel omnidirectional angle constraint based method for dynamic 6-DOF (six-degree-of-freedom) measurement. A photoelectric scanning measurement network is employed whose photoelectric receivers are fixed on the measured target. They are in a loop distribution and receive signals from rotating transmitters. Each receiver indicates an angle constraint direction. Therefore, omnidirectional angle constraints can be constructed in each rotation cycle. By solving the constrained optimization problem, 6-DOF information can be obtained, which is independent of traditional rigid coordinate system transformation. For the dynamic error caused by the measurement principle, we present an interpolation method for error reduction. Accuracy testing is performed in an 8  ×  8 m measurement area with four transmitters. The experimental results show that the dynamic orientation RMSEs (root-mean-square errors) are reduced from 0.077° to 0.044°, 0.040° to 0.030° and 0.032° to 0.015° in the X, Y, and Z axes, respectively. The dynamic position RMSE is reduced from 0.65 mm to 0.24 mm. This method is applied during the final approach phase in the rendezvous and docking simulation. Experiments under different conditions are performed in a 40  ×  30 m area, and the method is verified to be effective.

  8. An in-line fiber-optic modal interferometer for simultaneous measurement of twist and ambient temperature

    Yongqin Yu

    2014-12-01

    Full Text Available A novel and simple sensor based on fiber-optic modal interferometer fabricated by a segment of low elliptical hollow-core photonic bandgap fiber for simultaneous temperature and twist measurements is demonstrated. Meanwhile the sensor can also measure the twist angle and determine the twist direction simultaneously. The mode distribution of EHC-PBGF is demonstrated both in theory and experiments. There is an obvious difference of two transmission dips on the temperature and twist. The twist sensitivities of Dip 1 and Dip 2 are obtained to be −31.95 and −585.8 pm/(rad/m, respectively. The temperature sensitivities are 12.99 pm/°C for Dip 1 and 5.09 pm/°C for Dip 2, respectively. Two parameters of twist and temperature can be distinguished and measured simultaneously by using a sensing matrix. Meanwhile the structure is found to be weakly sensitive to the axial strain. It has the advantage of avoiding the crosstalk of strain in the applications.

  9. Simultaneous measurement of the concentrations of soot particles and gas species in light hydrocarbon flames using mass spectrometry

    Li, Qingxun; Liu, Fang; Wang, Dezheng; Wang, Tiefeng

    2014-01-01

    Besides gas species concentrations, soot volume fractions are also important data in the study of flames. This work describes the simultaneous measurement of the concentrations of soot and gas species in light hydrocarbon flames by in situ sampling and mass spectrometry (MS).The reaction medium was frozen by sampling into a very low-pressure tube, and the soot selectivity (proportion of carbon atoms in the reactant converted to soot) was determined from the C and H mass balances using the measured concentrations of the gas species and the mass of soot present per unit gas volume. The H/C ratio of the soot was measured by a thermogravimetry–mass spectrometry combination. The soot volume fraction was calculated from the soot selectivity and density of the soot. The soot selectivity measured by this reduced pressure sampling mass spectrometry (RPSMS) method was verified by measurements using the gravimetric sampling technique where the mass of soot collected in a volume of gas was weighed by a high precision balance. For most of the measurements, the uncertainty in the soot volume fraction was ±5%, but this would be larger when the soot volume fractions are less than 1 ppm. For demonstration, the RPSMS method was used to study a methane fuel-rich flame where the soot volume fractions were 1–5 ppm. The simultaneous measurement of concentrations of soot and gas species is useful for the quantitative study of flames. (paper)

  10. Estimating Torque Imparted on Spacecraft Using Telemetry

    Lee, Allan Y.; Wang, Eric K.; Macala, Glenn A.

    2013-01-01

    There have been a number of missions with spacecraft flying by planetary moons with atmospheres; there will be future missions with similar flybys. When a spacecraft such as Cassini flies by a moon with an atmosphere, the spacecraft will experience an atmospheric torque. This torque could be used to determine the density of the atmosphere. This is because the relation between the atmospheric torque vector and the atmosphere density could be established analytically using the mass properties of the spacecraft, known drag coefficient of objects in free-molecular flow, and the spacecraft velocity relative to the moon. The density estimated in this way could be used to check results measured by science instruments. Since the proposed methodology could estimate disturbance torque as small as 0.02 N-m, it could also be used to estimate disturbance torque imparted on the spacecraft during high-altitude flybys.

  11. Computer simulation of spacecraft/environment interaction

    Krupnikov, K.K.; Makletsov, A.A.; Mileev, V.N.; Novikov, L.S.; Sinolits, V.V.

    1999-01-01

    This report presents some examples of a computer simulation of spacecraft interaction with space environment. We analysed a set data on electron and ion fluxes measured in 1991-1994 on geostationary satellite GORIZONT-35. The influence of spacecraft eclipse and device eclipse by solar-cell panel on spacecraft charging was investigated. A simple method was developed for an estimation of spacecraft potentials in LEO. Effects of various particle flux impact and spacecraft orientation are discussed. A computer engineering model for a calculation of space radiation is presented. This model is used as a client/server model with WWW interface, including spacecraft model description and results representation based on the virtual reality markup language

  12. Computer simulation of spacecraft/environment interaction

    Krupnikov, K K; Mileev, V N; Novikov, L S; Sinolits, V V

    1999-01-01

    This report presents some examples of a computer simulation of spacecraft interaction with space environment. We analysed a set data on electron and ion fluxes measured in 1991-1994 on geostationary satellite GORIZONT-35. The influence of spacecraft eclipse and device eclipse by solar-cell panel on spacecraft charging was investigated. A simple method was developed for an estimation of spacecraft potentials in LEO. Effects of various particle flux impact and spacecraft orientation are discussed. A computer engineering model for a calculation of space radiation is presented. This model is used as a client/server model with WWW interface, including spacecraft model description and results representation based on the virtual reality markup language.

  13. Objective and Subjective Measures of Simultaneous vs Sequential Bilateral Cochlear Implants in Adults: A Randomized Clinical Trial.

    Kraaijenga, Véronique J C; Ramakers, Geerte G J; Smulders, Yvette E; van Zon, Alice; Stegeman, Inge; Smit, Adriana L; Stokroos, Robert J; Hendrice, Nadia; Free, Rolien H; Maat, Bert; Frijns, Johan H M; Briaire, Jeroen J; Mylanus, E A M; Huinck, Wendy J; Van Zanten, Gijsbert A; Grolman, Wilko

    2017-09-01

    To date, no randomized clinical trial on the comparison between simultaneous and sequential bilateral cochlear implants (BiCIs) has been performed. To investigate the hearing capabilities and the self-reported benefits of simultaneous BiCIs compared with those of sequential BiCIs. A multicenter randomized clinical trial was conducted between January 12, 2010, and September 2, 2012, at 5 tertiary referral centers among 40 participants eligible for BiCIs. Main inclusion criteria were postlingual severe to profound hearing loss, age 18 to 70 years, and a maximum duration of 10 years without hearing aid use in both ears. Data analysis was conducted from May 24 to June 12, 2016. The simultaneous BiCI group received 2 cochlear implants during 1 surgical procedure. The sequential BiCI group received 2 cochlear implants with an interval of 2 years between implants. First, the results 1 year after receiving simultaneous BiCIs were compared with the results 1 year after receiving sequential BiCIs. Second, the results of 3 years of follow-up for both groups were compared separately. The primary outcome measure was speech intelligibility in noise from straight ahead. Secondary outcome measures were speech intelligibility in noise from spatially separated sources, speech intelligibility in silence, localization capabilities, and self-reported benefits assessed with various hearing and quality of life questionnaires. Nineteen participants were randomized to receive simultaneous BiCIs (11 women and 8 men; median age, 52 years [interquartile range, 36-63 years]), and another 19 participants were randomized to undergo sequential BiCIs (8 women and 11 men; median age, 54 years [interquartile range, 43-64 years]). Three patients did not receive a second cochlear implant and were unavailable for follow-up. Comparable results were found 1 year after simultaneous or sequential BiCIs for speech intelligibility in noise from straight ahead (difference, 0.9 dB [95% CI, -3.1 to 4.4 dB]) and

  14. Simultaneous measurement of polymerization stress and curing kinetics for photo-polymerized composites with high filler contents.

    Wang, Zhengzhi; Landis, Forrest A; Giuseppetti, Anthony A M; Lin-Gibson, Sheng; Chiang, Martin Y M

    2014-12-01

    Photopolymerized composites are used in a broad range of applications with their performance largely directed by reaction kinetics and contraction accompanying polymerization. The present study was to demonstrate an instrument capable of simultaneously collecting multiple kinetics parameters for a wide range of photopolymerizable systems: degree of conversion (DC), reaction exotherm, and polymerization stress (PS). Our system consisted of a cantilever beam-based instrument (tensometer) that has been optimized to capture a large range of stress generated by lightly-filled to highly-filled composites. The sample configuration allows the tensometer to be coupled to a fast near infrared (NIR) spectrometer collecting spectra in transmission mode. Using our instrument design, simultaneous measurements of PS and DC are performed, for the first time, on a commercial composite with ≈80% (by mass) silica particle fillers. The in situ NIR spectrometer collects more than 10 spectra per second, allowing for thorough characterization of reaction kinetics. With increased instrument sensitivity coupled with the ability to collect real time reaction kinetics information, we show that the external constraint imposed by the cantilever beam during polymerization could affect the rate of cure and final degree of polymerization. The present simultaneous measurement technique is expected to provide new insights into kinetics and property relationships for photopolymerized composites with high filler content such as dental restorative composites. Published by Elsevier Ltd.

  15. Measurement of the neutron electric dipole moment: simultaneous spin analysis and preliminary data analysis

    Helaine, Victor

    2014-01-01

    In the framework of the neutron Electric Dipole Moment (nEDM) experiment at the Paul Scherrer Institut (Switzerland), this thesis deals with the development of a new system of spin analysis. The goal here is to simultaneously detect the two spin components of ultracold neutrons in order to increase the number of detected neutrons and therefore lower the nEDM statistical error. Such a system has been designed using Geant4-UCN simulations, built at LPC Caen and then tested as part of the experiment. In parallel to this work, the 2013 nEDM data taken at PSI have been analysed. Finally, methods to recover magnetic observables of first interest to control nEDM systematic errors have been studied and possible improvements are proposed. (author) [fr

  16. Simultaneous measurement of the strain tensor of 10 individual grains embedded in an Al tensile sample

    Martins, Rene V.; Margulies, Lawrence; Schmidt, Soeren; Poulsen, Henning F.; Leffers, Torben

    2004-01-01

    First results are presented on the simultaneous observation of the elastic strain tensor as a function of load of 10 individual grains, deeply embedded in the bulk of a polycrystalline Al tensile sample. The experimental technique is based on the use of focused high energy synchrotron radiation in transmission geometry. After each load step diffraction patterns are collected with a large-area X-ray detector system for a series of different angular and lateral sample positions. An automated indexing routine was used to assign sets of diffraction spots to individual grains. The strain tensor components as well as the individual grain position within the sample were then fitted from the diffraction spot positions. A maximum tensile load of 48 MPa was applied. Deviations in strain of up to 600 x 10 -6 are observed between respective strain components of individual grains

  17. Simultaneous measurement of ignition energy and current signature for brush discharges

    Fast, Lars; Andersson, Birgitta; Smallwood, Jeremy; Holdstock, Paul; Paasi, Jaakko

    2011-01-01

    Accurate prediction of the probability of ignition arising from charged insulators is a crucial element of risk assessment in process industry. Incendiary brush discharges can occur when a large or grounded conductor approaches a charged insulator in the presence of a flammable atmosphere. This paper describes ignition tests based on an IEC standard method and simultaneously recorded temporal distribution of current released in the discharges, using a discharge probe integrated with the ignition probe. Ignition and non-ignition results are compared with peak discharge current and charge transferred in the discharge. No clear ignition threshold was found for either of these parameters. No major differences were found between igniting and non-igniting waveforms.

  18. Simultaneously measured signals in scanning probe microscopy with a needle sensor: frequency shift and tunneling current.

    Morawski, Ireneusz; Voigtländer, Bert

    2010-03-01

    We present combined noncontact scanning force microscopy and tunneling current images of a platinum(111) surface obtained by means of a 1 MHz quartz needle sensor. The low-frequency circuit of the tunneling current was combined with a high-frequency signal of the quartz resonator enabling full electrical operation of the sensor. The frequency shift and the tunneling current were detected simultaneously, while the feedback control loop of the topography signal was fed using one of them. In both cases, the free signal that was not connected to the feedback loop reveals proportional-integral controller errorlike behavior, which is governed by the time derivative of the topography signal. A procedure is proposed for determining the mechanical oscillation amplitude by utilizing the tunneling current also including the average tip-sample work function.

  19. Impurity characterization of magnesium diuranate using simultaneous TG–DTA–FTIR measurements

    Raje, Naina, E-mail: nraje@barc.gov.in [Analytical Chemistry Division, B.A.R.C., Mumbai 400 085 (India); Ghonge, Darshana K. [Analytical Chemistry Division, B.A.R.C., Mumbai 400 085 (India); Hemantha Rao, G.V.S. [NFC, ECIL Post, Hyderabad (India); Reddy, A.V.R. [Analytical Chemistry Division, B.A.R.C., Mumbai 400 085 (India)

    2013-05-15

    Current studies describe the application of simultaneous thermogravimetry–differential thermal analysis – evolved gas analysis techniques for the compositional characterization of magnesium diuranate (MDU) with respect to the impurities present in the matrix. The stoichiometric composition of MDU was identified as MgU{sub 2}O{sub 7}⋅3H{sub 2}O. Presence of carbonate and sulphate as impurities in the matrix was confirmed through the evolved gas analysis using Fourier Transformation Infrared Spectrometry detection. Carbon and magnesium hydroxide content present as impurities in magnesium diuranate have been determined quantitatively using TG and FTIR techniques and the results are in good agreement. Powder X-ray diffraction analysis of magnesium diuranate suggests the presence of magnesium hydroxide as impurity in the matrix. Also these studies confirm the formation of magnesium uranate, uranium sesquioxide and uranium dioxide above 1000 °C, due to the decomposition of magnesium diuranate.

  20. Simultaneous measurement of temperature and emissivity of lunar regolith simulant using dual-channel millimeter-wave radiometry.

    McCloy, J S; Sundaram, S K; Matyas, J; Woskov, P P

    2011-05-01

    Millimeter wave (MMW) radiometry can be used for simultaneous measurement of emissivity and temperature of materials under extreme environments (high temperature, pressure, and corrosive environments). The state-of-the-art dual channel MMW passive radiometer with active interferometric capabilities at 137 GHz described here allows for radiometric measurements of sample temperature and emissivity up to at least 1600 °C with simultaneous measurement of sample surface dynamics. These capabilities have been used to demonstrate dynamic measurement of melting of powders of simulated lunar regolith and static measurement of emissivity of solid samples. The paper presents the theoretical background and basis for the dual-receiver system, describes the hardware in detail, and demonstrates the data analysis. Post-experiment analysis of emissivity versus temperature allows further extraction from the radiometric data of millimeter wave viewing beam coupling factors, which provide corroboratory evidence to the interferometric data of the process dynamics observed. These results show the promise of the MMW system for extracting quantitative and qualitative process parameters for industrial processes and access to real-time dynamics of materials behavior in extreme environments.

  1. Ultimate turbulence experiment: simultaneous measurements of Cn2 near the ground using six devices and eight methods

    Yatcheva, Lydia; Barros, Rui; Segel, Max; Sprung, Detlev; Sucher, Erik; Eisele, Christian; Gladysz, Szymon

    2015-10-01

    We have performed a series of experiments in order to simultaneously validate several devices and methods for measurement of the path-averaged refractive index structure constant ( 𝐶𝑛 2). The experiments were carried out along a horizontal urban path near the ground. Measuring turbulence in this layer is particularly important because of the prospect of using adaptive optics for free-space optical communications in an urban environment. On one hand, several commercial sensors were used: SLS20, a laser scintillometer from Scintec AG, BLS900, a largeaperture scintillometer, also from Scintec, and a 3D sonic anemometer from Thies GmbH. On the other hand, we measured turbulence strength with new approaches and devices developed in-house. Firstly, an LED array combined with a high-speed camera allowed for measurement of 𝐶𝑛 2 from raw- and differential image motion, and secondly a two-part system comprising a laser source, a Shack-Hartmann sensor and a PSF camera recoded turbulent modulation transfer functions, Zernike variances and angle-of-arrival structure functions, yielding three independent estimates of 𝐶𝑛 2. We compare the measured values yielded simultaneously by commercial and in-house developed devices and show very good agreement between 𝐶𝑛 2 values for all the methods. Limitations of each experimental method are also discussed.

  2. System for simultaneously measuring 6DOF geometric motion errors using a polarization maintaining fiber-coupled dual-frequency laser.

    Cui, Cunxing; Feng, Qibo; Zhang, Bin; Zhao, Yuqiong

    2016-03-21

    A novel method for simultaneously measuring six degree-of-freedom (6DOF) geometric motion errors is proposed in this paper, and the corresponding measurement instrument is developed. Simultaneous measurement of 6DOF geometric motion errors using a polarization maintaining fiber-coupled dual-frequency laser is accomplished for the first time to the best of the authors' knowledge. Dual-frequency laser beams that are orthogonally linear polarized were adopted as the measuring datum. Positioning error measurement was achieved by heterodyne interferometry, and other 5DOF geometric motion errors were obtained by fiber collimation measurement. A series of experiments was performed to verify the effectiveness of the developed instrument. The experimental results showed that the stability and accuracy of the positioning error measurement are 31.1 nm and 0.5 μm, respectively. For the straightness error measurements, the stability and resolution are 60 and 40 nm, respectively, and the maximum deviation of repeatability is ± 0.15 μm in the x direction and ± 0.1 μm in the y direction. For pitch and yaw measurements, the stabilities are 0.03″ and 0.04″, the maximum deviations of repeatability are ± 0.18″ and ± 0.24″, and the accuracies are 0.4″ and 0.35″, respectively. The stability and resolution of roll measurement are 0.29″ and 0.2″, respectively, and the accuracy is 0.6″.

  3. arXiv A method and tool for combining differential or inclusive measurements obtained with simultaneously constrained uncertainties

    Kieseler, Jan

    2017-11-22

    A method is discussed that allows combining sets of differential or inclusive measurements. It is assumed that at least one measurement was obtained with simultaneously fitting a set of nuisance parameters, representing sources of systematic uncertainties. As a result of beneficial constraints from the data all such fitted parameters are correlated among each other. The best approach for a combination of these measurements would be the maximization of a combined likelihood, for which the full fit model of each measurement and the original data are required. However, only in rare cases this information is publicly available. In absence of this information most commonly used combination methods are not able to account for these correlations between uncertainties, which can lead to severe biases as shown in this article. The method discussed here provides a solution for this problem. It relies on the public result and its covariance or Hessian, only, and is validated against the combined-likelihood approach. A d...

  4. Infrared Line Intensities for Formaldehyde from Simultaneous Measurements in the Infrared and Far Infrared Spectral Ranges

    Fissiaux, L.; Földes, T.; Tchana, F. Kwabia; Daumont, L.; Lepère, M.; Vander Auwera, J.

    2011-06-01

    Formaldehyde (H_2CO) is an important intermediate compound in the degradation of the volatile organic compounds (VOCs), including methane, in the terrestrial troposphere. Its observation using optical remote sensing in the infrared range relies on the 3.6 and 5.7 μm absorption bands. Band and individual line intensities have been reported in both ranges. With the present work, we aim to also derive infrared line intensities for formaldehyde, however relying on pure rotation line intensities and the known electric dipole moment to determine the particle density. Indeed, because formaldehyde polymerizes or degrades easily, the gas phase may contain polymerization or degradation products. Spectra of H_2CO diluted in 10 hPa of N_2 were therefore simultaneously recorded in the 20-60 Cm-1 and 3.6 μm ranges, respectively using a Bruker IFS125HR Fourier transform spectrometer and a tunable diode laser. see A. Perrin, D. Jacquemart, F. Kwabia Tchana, N. Lacome, J. Quant. Spectrosc. Radiat. Transfer 110 (2009) 700-716, and references therein

  5. What's hampering measurement invariance : Detecting non-invariant items using clusterwise simultaneous component analysis

    De Roover, K.; Timmerman, Marieke; De Leersnyder, J.; Mesquita, B.; Ceulemans, Eva

    2014-01-01

    The issue of measurement invariance is ubiquitous in the behavioral sciences nowadays as more and more studies yield multivariate multigroup data. When measurement invariance cannot be established across groups, this is often due to different loadings on only a few items. Within the multigroup CFA

  6. Simultaneous temperature measurement of ionospheric plasma and neutral atmosphere with K-10-11 rocket

    Murasato, Yukio; Kaneko, Osamu; Sasaki, Susumu; Kawashima, Nobuki; Kibune, Tadashi.

    1976-01-01

    Ion temperature and neutral atmospheric temperature in lower ionospheric layer were measured by the ''Shadow Method'', which has been developed and improved by the authors. The principle of the method, which utilizes the fact that the shadow due to the reduction of density of medium behind on obstacle depends upon the flow velocity and the temperature of the medium, is briefly explained together with the apparatus used for the measurement. A pair of the Langmuir probes with the interval of 44 mm was used for the measurement of ion temperature. For the measurement of the neutral atmospheric temperature, its density was measured with the ionization gauge. The measuring system was mounted on the K-10-11 rocket, and launched from KSC at 2 p.m., September 24, 1975. Although the rocket itself reached its highest altitude of 196 km, the temperature measurement was performed between the altitude of 80 km and 140 km. The measured temperatures of ions, neutral atmosphere, and electrons are presented as the functions of altitude. It is confirmed that the temperatures of ions and neutral atmosphere are lower than that of electrons in that range of altitude. (Aoki, K.)

  7. Simultaneous velocity and particle size measurement in two phase flows by Laser Anemometry

    Ungut, A.; Yule, A. J.; Taylor, D. S.; Chigier, N. A.

    1978-01-01

    A technique for particle size measurement by using Laser Doppler Anemometry is discussed. An additional gate photomultiplier has been introduced at right angles to the optical axis in order to select only those particles passing through the central region of the measurement control volume. Particle sizing measurements have been made in sprays of glass particles using the modified Laser Anemometry system. Measurements in fuel sprays are also reported and compared with the results obtained by a photographic technique. The application of the particle sizing technique to opaque particles is investigated and suitable optical arrangements are suggested. Light scattering characteristics of Laser Anemometry systems for different optical geometries are calculated to select the optimum optical arrangement for the particle sizing measurements.

  8. Dual mode antimony electrode for simultaneous measurements of PO2 and pH.

    Sjöberg, F; Nilsson, G

    2000-01-01

    In biomedical research and clinical medicine there is a demand for potent sensors to measure the components that make up blood gas analyses. Today, as when the electrochemical PO2, PCO2 and pH electrodes were first introduced, these measurements are usually made with the same type of sensor technology. The aims of the present study were, firstly, to find out whether the platinum cathode in the Clark electrode can be replaced by antimony for oxygen measurements (amperometry (A)); secondly, whether, during oxygen measurements, the inherent corrosion potential of the antimony metal can be used for measurement of pH in the same measurement area (potentiometry (P)). An electrode of purified, crystallographically orientated monocrystalline antimony (COMA) connected to a reference electrode (silver-silver chloride) was used for the P measurements. Measurements of A (at -900 mV) and P were made in an aqueous environment regulated for oxygen, pH, and temperature. Reproducible oxygen sensitivities of 0.925 nA/% oxygen (2% CV (coefficient of variation)) (A), 10.7 mV/% (P), and 0.7 mV/% (P) were found in the oxygen range: 0-21%, <5%, and above 5%, respectively. The pH sensitivity was 57 mV/pH unit (P). Oxygen and pH measurements were less accurate at oxygen concentrations close to 0%. Both the oxygen and pH part of the composite electrode signal can be identified by this dual mode technique (A and P). The sensor seems to be promising as it provides measurements of two separate variables (oxygen and pH) and also has the desirable characteristics of a solid state sensor.

  9. Micro-Structured Sapphire Fiber Sensors for Simultaneous Measurements of High-T and Dynamic Gas Pressure in Harsh Environments

    Xiao, Hai [Clemson Univ., SC (United States); Tsai, Hai-Lung [Missouri Univ. of Science and Technology, Rolla, MO (United States); Dong, Junhang [Univ. of Cincinnati, OH (United States)

    2014-09-30

    This is the final report for the program “Micro-Structured Sapphire Fiber Sensors for Simultaneous Measurements of High Temperature and Dynamic Gas Pressure in Harsh Environments”, funded by NETL, and performed by Missouri University of Science and Technology, Clemson University and University of Cincinnati from October 1, 2009 to September 30, 2014. Securing a sustainable energy economy by developing affordable and clean energy from coal and other fossil fuels is a central element to the mission of The U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL). To further this mission, NETL funds research and development of novel sensor technologies that can function under the extreme operating conditions often found in advanced power systems. The main objective of this research program is to conduct fundamental and applied research that will lead to successful development and demonstration of robust, multiplexed, microstructured silica and single-crystal sapphire fiber sensors to be deployed into the hot zones of advanced power and fuel systems for simultaneous measurements of high temperature and gas pressure. The specific objectives of this research program include: 1) Design, fabrication and demonstration of multiplexed, robust silica and sapphire fiber temperature and dynamic gas pressure sensors that can survive and maintain fully operational in high-temperature harsh environments. 2) Development and demonstration of a novel method to demodulate the multiplexed interferograms for simultaneous measurements of temperature and gas pressure in harsh environments. 3) Development and demonstration of novel sapphire fiber cladding and low numerical aperture (NA) excitation techniques to assure high signal integrity and sensor robustness.

  10. Simultaneous measurement of tritium and radiocarbon by ultra-low-background proportional counting.

    Mace, Emily; Aalseth, Craig; Alexander, Tom; Back, Henning; Day, Anthony; Hoppe, Eric; Keillor, Martin; Moran, Jim; Overman, Cory; Panisko, Mark; Seifert, Allen

    2017-08-01

    Use of ultra-low-background capabilities at Pacific Northwest National Laboratory provide enhanced sensitivity for measurement of low-activity sources of tritium and radiocarbon using proportional counters. Tritium levels are nearly back to pre-nuclear test backgrounds (~2-8 TU in rainwater), which can complicate their dual measurement with radiocarbon due to overlap in the beta decay spectra. We present results of single-isotope proportional counter measurements used to analyze a dual-isotope methane sample synthesized from ~120mg of H 2 O and present sensitivity results. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Comparison of the simultaneous measurement results of SCR fluxes received by geostationary satellites 'Electro-L' and 'GOES'

    Arakelov, A S; Burov, V A; Ochelkov, Y P

    2013-01-01

    In the present paper the comparison of the results of the simultaneous measurements of solar proton fluxes on board geostationary satellites 'GOES' and 'Electro' was made for the purpose of calibration of 'Electro-L' detectors and determination of the possibility to utilize 'Electro-L' data for space weather monitoring. It was shown that the solar proton observation data on board 'Electro-L' recalculated to energy thresholds of 'GOES' 10 and 30 MeV are in a good consistent with 'GOES' data and may be used for control of radiation conditions in near-earth space.

  12. The local domain wall position in ferromagnetic thin wires: simultaneous measurement of resistive and transverse voltages at multiple points

    Hanada, R.; Sugawara, H.; Aoki, Y.; Sato, H.; Shigeto, K.; Shinjo, T.; Ono, T.; Miyajima, H.

    2002-01-01

    We have simultaneously measured the field dependences of voltages at multiple pairs of resistance and transverse voltage probes in ferromagnetic wires (with either magnetic or non-magnetic voltage probes). Both the resistive (through the giant magnetoresistance and anisotropic magnetoresistance) and transverse voltages (through the planar Hall effect) exhibit abrupt jumps, reflecting discrete motion of domain walls or rotations of magnetization. Voltage probes, even if non-magnetic, are found to affect the jump fields depending on the sample conditions. We demonstrate that the specific information on the domain (wall) motion along a thin ferromagnetic wire could be obtained from the jump fields. (author)

  13. Simultaneous multipoint measurements of density gradients and temperature in a flame. Progress report, July 1, 1982-January 31, 1983

    Chang, R.K.; Chu, B.T.; Long, M.B.

    1983-02-01

    An account is given of recent progress in the development of nonintrusive optical diagnostic techniques and the application of these techniques to turbulent combustion systems. The primary focus of the work over the past year has been in: (1) the use of a broadband rotational CARS technique for the measurement of temperature in flames, and (2) the use of spontaneous Raman scattering to simultaneously map out the fuel gas concentration in a turbulent diffusion flame at 2500 points in a plane intersecting the flow. A summary of new results in each of these areas is given

  14. Simultaneous Measurement of Nitrogen and Oxygen Isotopes of Nitrate to Evaluate Nitrate Sources and Processes in Catchments

    Ohte, Nobuhito [Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo (Japan); Nagata, Toshi; Tayasu, Ichiro [Center for Ecological Research, Kyoto University, Ohtsu (Japan); Kyozu, Ayato; Yoshimizu, Chikage [CREST, Japan Science and Technology Agency, Center for Ecological Research, Kyoto University, Ohtsu (Japan); Osaka, Ken' ichi [Carbon and Nutrient Cycles Division, National Institute for Agro-Environmental Sciences, Tsukuba, (Japan)

    2013-05-15

    We review studies on applied isotope analytical techniques for identifying sources and transformations of river nitrate (NO{sub 3}{sup -}) to examine the influences of water pollution, excess nutrient (nitrogen) loads and ecosystem disturbances in river systems. We also discuss the current status and future perspectives of the application of NO{sub 3}{sup -} isotope measurements to the assessment of river nutrients. Our review shows that in recent years simultaneous measurements of nitrogen and oxygen isotopes ({delta}{sup 15}N and {delta}{sup 18}O) of NO{sub 3}{sup -} have been increasingly used to identify the sources and pathways of nitrogen in river systems. The {delta}{sup 15}N value of NO{sub 3}{sup -} is a useful indicator to evaluate the contributions of sewage and/or animal waste to NO{sub 3}{sup -} load, and the {delta}{sup 18}O value can be used for estimation of the contribution of NO{sub 3}{sup -} derived through atmospheric deposition. The microbial denitrification method is currently a most useful tool to measure the {delta}{sup 15}N and {delta}{sup 18}O values of NO{sub 3}{sup -} simultaneously, because of its capability for high throughput of samples. This method allows us to conduct a comprehensive investigation of spatial and temporal variations and mechanisms of nitrogen transport and transformation in rivers and catchments in more precise and effective manner. (author)

  15. Effects of flow changes on radiotracer binding: Simultaneous measurement of neuroreceptor binding and cerebral blood flow modulation.

    Sander, Christin Y; Mandeville, Joseph B; Wey, Hsiao-Ying; Catana, Ciprian; Hooker, Jacob M; Rosen, Bruce R

    2017-01-01

    The potential effects of changes in blood flow on the delivery and washout of radiotracers has been an ongoing question in PET bolus injection studies. This study provides practical insight into this topic by experimentally measuring cerebral blood flow (CBF) and neuroreceptor binding using simultaneous PET/MRI. Hypercapnic challenges (7% CO 2 ) were administered to non-human primates in order to induce controlled increases in CBF, measured with pseudo-continuous arterial spin labeling. Simultaneously, dopamine D 2 /D 3 receptor binding of [ 11 C]raclopride or [ 18 F]fallypride was monitored with dynamic PET. Experiments showed that neither time activity curves nor quantification of binding through binding potentials ( BP ND ) were measurably affected by CBF increases, which were larger than two-fold. Simulations of experimental procedures showed that even large changes in CBF should have little effect on the time activity curves of radiotracers, given a set of realistic assumptions. The proposed method can be applied to experimentally assess the flow sensitivity of other radiotracers. Results demonstrate that CBF changes, which often occur due to behavioral tasks or pharmacological challenges, do not affect PET [ 11 C]raclopride or [ 18 F]fallypride binding studies and their quantification. The results from this study suggest flow effects may have limited impact on many PET neuroreceptor tracers with similar properties.

  16. A setup for simultaneous measurement of infrared spectra and light scattering signals: Watching amyloid fibrils grow from intact proteins

    Li, Yang; Maurer, Jürgen; Roth, Andreas; Vogel, Vitali; Winter, Ernst; Mäntele, Werner, E-mail: maentele@biophysik.uni-frankfurt.de [Institut für Biophysik, Goethe-Universität Frankfurt am Main, Max-von Laue-Straße 1, D-60438 Frankfurt am Main (Germany)

    2014-08-15

    A setup for the simultaneous measurement of mid-infrared spectra and static light scattering is described that can be used for the analysis of the formation of nanoscale and microscopic aggregates from smaller molecules to biopolymers. It can be easily integrated into sample chambers of infrared spectrometers or combined with laser beams from tunable infrared lasers. Here, its use for the analysis of the formation of amyloid fibrils from intact proteins is demonstrated. The formation of amyloid fibrils or plaques from proteins is a widespread and pathogenetic relevant process, and a number of diseases are caused and correlated with the deposition of amyloid fibrils in cells and tissues. The molecular mechanisms of these transformations, however, are still unclear. We report here the simultaneous measurement of infrared spectra and static light scattering for the analysis of fibril formation from egg-white lysozyme. The transformation of the native form into non-native forms rich in β-sheet structure is measured by analysis of the amide I spectral region in the infrared spectra, which is sensitive for local structures. At the same time, light scattering signals at forward direction as well as the forward/backward ratio, which are sensitive for the number of scattering centers and their approximate sizes, respectively, are collected for the analysis of fibril growth. Thermodynamic and kinetic parameters as well as mechanistic information are deduced from the combination of the two complementary techniques.

  17. A setup for simultaneous measurement of infrared spectra and light scattering signals: Watching amyloid fibrils grow from intact proteins

    Li, Yang; Maurer, Jürgen; Roth, Andreas; Vogel, Vitali; Winter, Ernst; Mäntele, Werner

    2014-08-01

    A setup for the simultaneous measurement of mid-infrared spectra and static light scattering is described that can be used for the analysis of the formation of nanoscale and microscopic aggregates from smaller molecules to biopolymers. It can be easily integrated into sample chambers of infrared spectrometers or combined with laser beams from tunable infrared lasers. Here, its use for the analysis of the formation of amyloid fibrils from intact proteins is demonstrated. The formation of amyloid fibrils or plaques from proteins is a widespread and pathogenetic relevant process, and a number of diseases are caused and correlated with the deposition of amyloid fibrils in cells and tissues. The molecular mechanisms of these transformations, however, are still unclear. We report here the simultaneous measurement of infrared spectra and static light scattering for the analysis of fibril formation from egg-white lysozyme. The transformation of the native form into non-native forms rich in β-sheet structure is measured by analysis of the amide I spectral region in the infrared spectra, which is sensitive for local structures. At the same time, light scattering signals at forward direction as well as the forward/backward ratio, which are sensitive for the number of scattering centers and their approximate sizes, respectively, are collected for the analysis of fibril growth. Thermodynamic and kinetic parameters as well as mechanistic information are deduced from the combination of the two complementary techniques.

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

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

    2017-04-01

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

  19. Simultaneous measurement of tritium and radiocarbon by ultra-low-background proportional counting

    Mace, Emily; Aalseth, Craig; Alexander, Tom; Back, Henning; Day, Anthony; Hoppe, Eric; Keillor, Martin; Moran, Jim; Overman, Cory; Panisko, Mark; Seifert, Allen

    2017-08-01

    Use of ultra-low-background capabilities at Pacific Northwest National Laboratory provide enhanced sensitivity for measurement of low-activity sources of tritium and radiocarbon using proportional counters. Tritium levels are nearly back to pre-nuclear test backgrounds (~2-8 TU in rainwater), which can complicate their dual measurement with radiocarbon due to overlap in the isotope’s respective energy spectra. This activity makes direct dual-isotope measurements challenging without additional chemistry to concentrate the tritium in a sample. We present results of single-isotope proportional counter measurements used to analyze a dual-isotope methane sample synthesized from ~120 mg of H2O and present sensitivity results.

  20. Final results of the Resonance spacecraft calibration effort

    Sampl, Manfred; Macher, Wolfgang; Gruber, Christian; Oswald, Thomas; Rucker, Helmut O.

    2010-05-01

    We report our dedicated analyses of electrical field sensors onboard the Resonance spacecraft with a focus on the high-frequency electric antennas. The aim of the Resonance mission is to investigate wave-particle interactions and plasma dynamics in the inner magnetosphere of the Earth, with a focus on phenomena occurring along the same field line and within the same flux tube of the Earth's magnetic field. Four spacecraft will be launched, in the middle of the next decade, to perform these observations and measurements. Amongst a variety of instruments and probes several low- and high-frequency electric sensors will be carried which can be used for simultaneous remote sensing and in-situ measurements. The high-frequency electric sensors consist of cylindrical antennas mounted on four booms extruded from the central body of the spacecraft. In addition, the boom rods themselves are used together with the these sensors for mutual impedance measurements. Due to the parasitic effects of the conducting spacecraft body the electrical antenna representations (effective length vector, capacitances) do not coincide with their physical representations. The analysis of the reception properties of these antennas is presented, along with a contribution to the understanding of their impairment by other objects; in particular the influence of large magnetic loop sensors is studied. In order to analyse the antenna system, we applied experimental and numerical methods. The experimental method, called rheometry, is essentially an electrolytic tank measurement, where a scaled-down spacecraft model is immersed into an electrolytic medium (water) with corresponding measurements of voltages at the antennas. The numerical method consists of a numerical solution of the underlying field equations by means of computer programs, which are based on wire-grid and patch-grid models. The experimental and numerical results show that parasitic effects of the antenna-spacecraft assembly alter the

  1. Results from active spacecraft potential control on the Geotail spacecraft

    Schmidt, R.; Arends, H.; Pedersen, A.

    1995-01-01

    A low and actively controlled electrostatic potential on the outer surfaces of a scientific spacecraft is very important for accurate measurements of cold plasma electrons and ions and the DC to low-frequency electric field. The Japanese/NASA Geotail spacecraft carriers as part of its scientific payload a novel ion emitter for active control of the electrostatic potential on the surface of the spacecraft. The aim of the ion emitter is to reduce the positive surface potential which is normally encountered in the outer magnetosphere when the spacecraft is sunlit. Ion emission clamps the surface potential to near the ambient plasma potential. Without emission control, Geotail has encountered plasma conditions in the lobes of the magnetotail which resulted in surface potentials of up to about +70 V. The ion emitter proves to be able to discharge the outer surfaces of the spacecraft and is capable of keeping the surface potential stable at about +2 V. This potential is measured with respect to one of the electric field probes which are current biased and thus kept at a potential slightly above the ambient plasma potential. The instrument uses the liquid metal field ion emission principle to emit indium ions. The ion beam energy is about 6 keV and the typical total emission current amounts to about 15 μA. Neither variations in the ambient plasma conditions nor operation of two electron emitters on Geotail produce significant variations of the controlled surface potential as long as the resulting electron emission currents remain much smaller than the ion emission current. Typical results of the active potential control are shown, demonstrating the surface potential reduction and its stability over time. 25 refs., 5 figs

  2. Fiber based optical tweezers for simultaneous in situ force exertion and measurements in a 3D polyacrylamide gel compartment.

    Ti, Chaoyang; Thomas, Gawain M; Ren, Yundong; Zhang, Rui; Wen, Qi; Liu, Yuxiang

    2015-07-01

    Optical tweezers play an important role in biological applications. However, it is difficult for traditional optical tweezers based on objective lenses to work in a three-dimensional (3D) solid far away from the substrate. In this work, we develop a fiber based optical trapping system, namely inclined dual fiber optical tweezers, that can simultaneously apply and measure forces both in water and in a 3D polyacrylamide gel matrix. In addition, we demonstrate in situ, non-invasive characterization of local mechanical properties of polyacrylamide gel by measurements on an embedded bead. The fiber optical tweezers measurements agree well with those of atomic force microscopy (AFM). The inclined dual fiber optical tweezers provide a promising and versatile tool for cell mechanics study in 3D environments.

  3. Comparing Simultaneous Stratospheric Aerosol and Ozone Lidar Measurements with SAGE 2 Data after the Mount Pinatubo Eruption

    Yue, G. K.; Poole, L. R.; McCormick, M. P.; Veiga, R. E.; Wang, P.-H.; Rizi, V.; Masci, F.; DAltorio, A.; Visconti, G.

    1995-01-01

    Stratospheric aerosol and ozone profiles obtained simultaneously from the lidar station at the University of L'Aquila (42.35 deg N, 13.33 deg E, 683 m above sea level) during the first 6 months following the eruption of Mount Pinatubo are compared with corresponding nearby Stratospheric Aerosol and Gas Experiment (SAGE) 2 profiles. The agreement between the two data sets is found to be reasonably good. The temporal change of aerosol profiles obtained by both techniques showed the intrusion and growth of Pinatubo aerosols. In addition, ozone concentration profiles derived from an empirical time-series model based on SAGE 2 ozone data obtained before the Pinatubo eruption are compared with measured profiles. Good agreement is shown in the 1991 profiles, but ozone concentrations measured in January 1992 were reduced relative to time-series model estimates. Possible reasons for the differences between measured and model-based ozone profiles are discussed.

  4. Radio wave scattering observations of the solar corona: First-order measurements of expansion velocity and turbulence spectrum using Viking and Mariner 10 spacecraft

    Tyler, G.L.; Vesecky, J.F.; Plume, M.A.; Howard, H.T.; Barnes, A.

    1981-01-01

    Solar conjunction of Mars on 1976 November 25 occurred very near the beginning of solar cycle 21, about 4 months after the first Viking spacecraft arrived at the planet. Radio wave scattering data were collected at 3.6 and 13 cm wavelengths, using the radio link between the Viking orbiters and the Earth. These data allow measurements of solar wind properties over a range of heliocentric radial distance from approx.6 to 44 R/sub sun/ with solar latitudes ranging from -17 0 to +7 0 . Observations with Mariner 10 during a period of moderate solar activity in 1974 cover from 6 to 24 R/sub sun/ and from approx.20 0 to near 90 0 . We have found that the temporal frequency variance spectrum of amplitude fluctuations is useful for characterizing the bulk motion of the plasma. This spectrum has an approximately constant low frequency plateau and a power-law high frequency asymptote; the plateau-asymptote intersection frequency provides a measure of the solar wind velocity V. We also obtain the spectral index p of electron density turbulence, Phi/sub N/approx.kappa/sup -p/, where kappa is spatial wavenumber. These results apply to a cylindrical region oriented with its axis along the radio ray path and its center at the point of closest approach to the Sun. The measurements of V and p cover some 78/sup d/ for Viking and 49 2 for Mariner 10 and show the combined effects of changing heliocentric distance rho, solar latitude theta, and solar longitude Psi, as well as solar activity. The Viking results can be regarded as a function primary of rho and Psi since the observations are concentrated in the equatorial regions when solar activity was near minimum. For Mariner 10, rho, theta, and Psi variations were important. The Viking results show an abrupt change in V(rho) and the turbulence spectral index at approx.15 R/sub sun/

  5. Simultaneous determination of aerosol optical thickness and water-leaving radiance from multispectral measurements in coastal waters

    Shi, Chong; Nakajima, Teruyuki

    2018-03-01

    Retrieval of aerosol optical properties and water-leaving radiance over ocean is challenging since the latter mostly accounts for ˜ 10 % of the satellite-observed signal and can be easily influenced by the atmospheric scattering. Such an effort would be more difficult in turbid coastal waters due to the existence of optically complex oceanic substances or high aerosol loading. In an effort to solve such problems, we present an optimization approach for the simultaneous determination of aerosol optical thickness (AOT) and normalized water-leaving radiance (nLw) from multispectral satellite measurements. In this algorithm, a coupled atmosphere-ocean radiative transfer model combined with a comprehensive bio-optical oceanic module is used to jointly simulate the satellite-observed reflectance at the top of atmosphere and water-leaving radiance just above the ocean surface. Then, an optimal estimation method is adopted to retrieve AOT and nLw iteratively. The algorithm is validated using Aerosol Robotic Network - Ocean Color (AERONET-OC) products selected from eight OC sites distributed over different waters, consisting of observations that covered glint and non-glint conditions from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument. Results show a good consistency between retrieved and in situ measurements at each site. It is demonstrated that more accurate AOTs are determined based on the simultaneous retrieval method, particularly in shorter wavelengths and sunglint conditions, where the averaged percentage difference (APD) of retrieved AOT is generally reduced by approximate 10 % in visible bands compared with those derived from the standard atmospheric correction (AC) scheme, since all the spectral measurements can be used jointly to increase the information content in the inversion of AOT, and the wind speed is also simultaneously retrieved to compensate the specular reflectance error estimated from the rough ocean surface model. For the

  6. Simultaneous Treatment of Missing Data and Measurement Error in HIV Research Using Multiple Overimputation.

    Schomaker, Michael; Hogger, Sara; Johnson, Leigh F; Hoffmann, Christopher J; Bärnighausen, Till; Heumann, Christian

    2015-09-01

    Both CD4 count and viral load in HIV-infected persons are measured with error. There is no clear guidance on how to deal with this measurement error in the presence of missing data. We used multiple overimputation, a method recently developed in the political sciences, to account for both measurement error and missing data in CD4 count and viral load measurements from four South African cohorts of a Southern African HIV cohort collaboration. Our knowledge about the measurement error of ln CD4 and log10 viral load is part of an imputation model that imputes both missing and mismeasured data. In an illustrative example, we estimate the association of CD4 count and viral load with the hazard of death among patients on highly active antiretroviral therapy by means of a Cox model. Simulation studies evaluate the extent to which multiple overimputation is able to reduce bias in survival analyses. Multiple overimputation emphasizes more strongly the influence of having high baseline CD4 counts compared to both a complete case analysis and multiple imputation (hazard ratio for >200 cells/mm vs. <25 cells/mm: 0.21 [95% confidence interval: 0.18, 0.24] vs. 0.38 [0.29, 0.48], and 0.29 [0.25, 0.34], respectively). Similar results are obtained when varying assumptions about measurement error, when using p-splines, and when evaluating time-updated CD4 count in a longitudinal analysis. The estimates of the association with viral load are slightly more attenuated when using multiple imputation instead of multiple overimputation. Our simulation studies suggest that multiple overimputation is able to reduce bias and mean squared error in survival analyses. Multiple overimputation, which can be used with existing software, offers a convenient approach to account for both missing and mismeasured data in HIV research.

  7. Using microencapsulated fluorescent dyes for simultaneous measurement of temperature and velocity fields

    Vogt, J; Stephan, P

    2012-01-01

    In this paper, a novel particle image thermometry method based on microcapsules filled with a fluorescent dye solution is described. The microcapsules consist of a liquid core of hexadecane in which the dye is dissolved and a solid polymer shell. The combination of a temperature-sensitive dye (Pyrromethene 597-8C9) and a dye showing a relatively smaller temperature sensitivity (Pyrromethene 567) in hexadecane makes application of the ratiometric LIF possible. This is necessary to compensate for fluctuations of the illuminating pulsed Nd:YAG laser (532 nm) as well as the different particle sizes. The applicability of this measurement technique is demonstrated for a cubic test cell (10 × 10 × 10 mm 3 ) with flow and temperature fields driven by natural convection and a capillary tube (1.16 mm inner diameter) inducing a temperature gradient and a Hagen–Poiseuille velocity profile. For the first case, a light sheet illumination is used making two optical accesses necessary. In the second case an inverted microscope is used, so only one optical access is needed and a volume illumination is applied. The technique facilitates high-resolution measurements (first case: 79 × 79 μm 2 ; second case: 8 × 8 μm 2 ). Although the measurement uncertainty is high compared to LIF measurements with dissolved dyes, temperature fields can be reproduced very well, and the experimental results are in good agreement with numerical computations. (paper)

  8. Simultaneous measurement and quantitation of 4-hydroxyphenylacetic acid and dopamine with fast-scan cyclic voltammetry.

    Shin, Mimi; Kaplan, Sam V; Raider, Kayla D; Johnson, Michael A

    2015-05-07

    Caged compounds have been used extensively to investigate neuronal function in a variety of preparations, including cell culture, ex vivo tissue samples, and in vivo. As a first step toward electrochemically measuring the extent of caged compound photoactivation while also measuring the release of the catecholamine neurotransmitter, dopamine, fast-scan cyclic voltammetry at carbon-fiber microelectrodes (FSCV) was used to electrochemically characterize 4-hydroxyphenylacetic acid (4HPAA) in the absence and presence of dopamine. 4HPAA is a by-product formed during the process of photoactivation of p-hydroxyphenacyl-based caged compounds, such as p-hydroxyphenylglutamate (pHP-Glu). Our data suggest that the oxidation of 4HPAA occurs through the formation of a conjugated species. Moreover, we found that a triangular waveform of -0.4 V to +1.3 V to -0.4 V at 600 V s(-1), repeated every 100 ms, provided an oxidation current of 4HPAA that was enhanced with a limit of detection of 100 nM, while also allowing the detection and quantitation of dopamine within the same scan. Along with quantifying 4HPAA in biological preparations, the results from this work will allow the electrochemical measurement of photoactivation reactions that generate 4HPAA as a by-product as well as provide a framework for measuring the photorelease of electroactive by-products from caged compounds that incorporate other chromophores.

  9. Microvascular and mitochondrial PO 2 simultaneously measured by oxygen-dependent delayed luminescence

    S.I.A. Bodmer (Sander I. A.); G. Balestra (Gianmarco); F.A. Harms (Floor A.); T. Johannes (Tanja); N.J.H. Raat (Nicolaas); R.J. Stolker (Robert); E.G. Mik (Egbert)

    2012-01-01

    textabstractMeasurement of tissue oxygenation is a complex task and various techniques have led to a wide range of tissue PO 2 values and contradictory results. Tissue is compartmentalized in microcirculation, interstitium and intracellular space and current techniques are biased towards a certain

  10. Simultaneous Infrared And Pressure Measurements Of Crossflow Instability Modes For HIFiRE 5 (POSTPRINT)

    2017-07-01

    contained streamwise-distributed arrays of pressure sensors well upstream of the one measuring station available on the previous model. The streamwise...P. Borg and Roger L. Kimmel Hypersonic Sciences Branch High Speed Systems Division JULY 2017 DISTRIBUTION STATEMENT A...PAO) and is available to the general public, including foreign nationals. Copies may be obtained from the Defense Technical Information Center

  11. High precision optical measurement of displacement and simultaneous determinations of piezoelectric coefficients

    Gamboa, Bryan M.; Malladi, Madhuri; Vadlamani, Ramya; Guo, Ruyan; Bhalla, Amar

    2016-09-01

    PZT are also well known for their applications in Micro Electrical Mechanical Systems (MEMS). It is necessary to study the piezoelectric coefficients of the materials accurately in order to design a sensor as an example, which defines their strain dependent applications. Systematic study of the electro mechanic displacement measurement was conducted and compared using a white light fiber optic sensor, a heterodyne laser Doppler vibrometer, and a homodyne laser interferometry setup. Frequency dependent measurement is conducted to evaluate displacement values well below and near the piezoelectric resonances. UHF-120 ultra-high frequency Vibrometer is used to measure the longitudinal piezoelectric displacement or x33 and the MTI 2000 FotonicTM Sensor is used to measure the transverse piezoelectric displacement or x11 over 100Hz to 2MHz. A Multiphysics Finite Element Analysis method, COMSOL, is also adopted in the study to generate a three dimensional electromechanical coupled model based on experimentally determined strains x33 and x11 as a function of frequency of the electric field applied. The full family of piezoelectric coefficients of the poled electronic ceramic PZT, d33, d31, and d15, can be then derived, upon satisfactory simulation of the COMSOL. This is achieved without the usual need of preparation of piezoelectric resonators of fundamental longitudinal, transversal, and shear modes respectively.

  12. Simultaneous measurement of a fluid flow and the fluid's free surface using PIV

    Philip, O.G.; Hassan, Y.A.; Okamoto, K.

    1995-01-01

    The objective of this investigation is to study the interaction between a fluid flow and its free surface with an improved application of the flow measurement technique, particle image velocimetry (PIV). In this study, improvements in the data acquisition and tracking method of the PIV technique were developed

  13. Simultaneous measurement of thermal conductivity and heat capacity by flash thermal imaging methods

    Tao, N.; Li, X. L.; Sun, J. G.

    2017-06-01

    Thermal properties are important for material applications involved with temperature. Although many measurement methods are available, they may not be convenient to use or have not been demonstrated suitable for testing of a wide range of materials. To address this issue, we developed a new method for the nondestructive measurement of the thermal effusivity of bulk materials with uniform property. This method is based on the pulsed thermal imaging-multilayer analysis (PTI-MLA) method that has been commonly used for testing of coating materials. Because the test sample for PTI-MLA has to be in a two-layer configuration, we have found a commonly used commercial tape to construct such test samples with the tape as the first-layer material and the bulk material as the substrate. This method was evaluated for testing of six selected solid materials with a wide range of thermal properties covering most engineering materials. To determine both thermal conductivity and heat capacity, we also measured the thermal diffusivity of these six materials by the well-established flash method using the same experimental instruments with a different system setup. This paper provides a description of these methods, presents detailed experimental tests and data analyses, and discusses measurement results and their comparison with literature values.

  14. Simultaneous temporally resolved DPIV and pressure measurements of symmetric oscillations in a scaled-up vocal fold model

    Ringenberg, Hunter; Rogers, Dylan; Wei, Nathaniel; Krane, Michael; Wei, Timothy

    2017-11-01

    The objective of this study is to apply experimental data to theoretical framework of Krane (2013) in which the principal aeroacoustic source is expressed in terms of vocal fold drag, glottal jet dynamic head, and glottal exit volume flow, reconciling formal theoretical aeroacoustic descriptions of phonation with more traditional lumped-element descriptions. These quantities appear in the integral equations of motion for phonatory flow. In this way time resolved velocity field measurements can be used to compute time-resolved estimates of the relevant terms in the integral equations of motion, including phonation aeroacoustic source strength. A simplified 10x scale vocal fold model from Krane, et al. (2007) was used to examine symmetric, i.e. `healthy', oscillatory motion of the vocal folds. By using water as the working fluid, very high spatial and temporal resolution was achieved. Temporal variation of transglottal pressure was simultaneously measured with flow on the vocal fold model mid-height. Experiments were dynamically scaled to examine a range of frequencies corresponding to male and female voice. The simultaneity of the pressure and flow provides new insights into the aeroacoustics associated with vocal fold oscillations. Supported by NIH Grant No. 2R01 DC005642-11.

  15. Cascaded-cavity Fabry-Perot interferometer for simultaneous measurement of temperature and strain with cross-sensitivity compensation

    Tian, Jiajun; Jiao, Yuzhu; Ji, Shaobo; Dong, Xiaolong; Yao, Yong

    2018-04-01

    We propose and demonstrate a fiber sensor for simultaneous temperature and strain measurements. The proposed sensor is implemented by a cascaded-cavity Fabry-Perot (FP) fiber interferometer. The two cascaded FP cavities comprise a micro-air-cavity in a hollow-core tube fiber and a micro-silica-cavity in a standard single-mode fiber. To separate the interference spectrum of each FP cavity, the total spectrum is filtered in the frequency domain through band-pass filters, whose central frequencies were predesigned based on the relationship between the spatial frequency and free spectral range of each FP cavity. The different cross-sectional areas and thermal-optic coefficients of the two FP cavities confer different sensitivities to temperature and strain. Both parameters were measured simultaneously by tracking the wavelength shifts in the filtered interference spectra of the FP cavities. Moreover, the temperature-strain cross-sensitivity was compensated by solving a sensitivity-coefficient matrix equation for the two cavities, using the calibrated temperatures and strains. Other advantages of the proposed sensor are simple fabrication and an all-fiber structure. Owing to these properties, the proposed sensor is potentially applicable to real sensing applications.

  16. Simultaneous measurement of thermal diffusivity and effusivity of solids using the flash technique in the front-face configuration

    Pech-May, Nelson Wilbur; Cifuentes, Ángel; Mendioroz, Arantza; Oleaga, Alberto; Salazar, Agustín

    2015-01-01

    Both thermal diffusivity and effusivity (or conductivity) are necessary to characterize the thermal transport properties of a material. The flash method is the most recognized procedure to measure the thermal diffusivity of free-standing opaque plates. However, it fails to simultaneously obtain the thermal effusivity (or conductivity). This is due to the difficulty of knowing the total energy absorbed by the sample surface after the light pulse. In this work, we propose using the flash method in the front-face configuration on a two-layer system made of the unknown plate and a fluid of known thermal properties. We demonstrate that the surface temperature is sensitive to the thermal mismatch between the plate and the fluid, which is governed by their thermal effusivity ratio. In order to verify the validity of the method and to establish its application limits we have performed flash measurements, using a pulsed laser and an infrared camera, on a set of calibrated materials (metals, alloys, ceramics and polymers) covering a wide range of thermal transport properties. These results confirm the ability of the flash method to simultaneously retrieve thermal diffusivity and effusivity in a fast manner in samples whose effusivities are lower than three times the effusivity of the liquid used as backing fluid. (paper)

  17. Airborne particulate matter in spacecraft

    1988-01-01

    Acceptability limits and sampling and monitoring strategies for airborne particles in spacecraft were considered. Based on instances of eye and respiratory tract irritation reported by Shuttle flight crews, the following acceptability limits for airborne particles were recommended: for flights of 1 week or less duration (1 mg/cu m for particles less than 10 microns in aerodynamic diameter (AD) plus 1 mg/cu m for particles 10 to 100 microns in AD); and for flights greater than 1 week and up to 6 months in duration (0.2 mg/cu m for particles less than 10 microns in AD plus 0.2 mg/cu m for particles 10 to 100 microns in AD. These numerical limits were recommended to aid in spacecraft atmosphere design which should aim at particulate levels that are a low as reasonably achievable. Sampling of spacecraft atmospheres for particles should include size-fractionated samples of 0 to 10, 10 to 100, and greater than 100 micron particles for mass concentration measurement and elementary chemical analysis by nondestructive analysis techniques. Morphological and chemical analyses of single particles should also be made to aid in identifying airborne particulate sources. Air cleaning systems based on inertial collection principles and fine particle collection devices based on electrostatic precipitation and filtration should be considered for incorporation into spacecraft air circulation systems. It was also recommended that research be carried out in space in the areas of health effects and particle characterization.

  18. Novel Faraday cup for the simultaneous observation and measurement of ion-beam currents

    Wei, C.Y.; Seidman, D.N.

    1977-07-01

    The Faraday cup is constructed around a Galileo channel electron multiplier array (CEMA) which serves as the basis of an internal image intensification system (a gain of greater than 10 4 ) for the observation of the ion beam; the CEMA also acts as a collector for the ion cured by a Keithley 602 electrometer. The ion current is integrated by a simple and inexpensive dosimeter; the electronic circuit for the dosimeter is described. The application of the Faraday cup to the observation and measurement of a 30 keV Ar + ion beam is presented as an illustrative example. This Faraday cup was also employed to observe and measure 30 keV Cr + , Mo + or W + and 18 keV Au + ion beams employed for the in-situ irradiation of field-ion microscope specimens

  19. Measurement of rotational dynamics by the simultaneous nonlinear analysis of optical and EPR data.

    Hustedt, E J; Cobb, C E; Beth, A H; Beechem, J M

    1993-01-01

    In the preceding companion article in this issue, an optical dye and a nitroxide radical were combined in a new dual function probe, 5-SLE. In this report, it is demonstrated that time-resolved optical anisotropy and electron paramagnetic resonance (EPR) data can be combined in a single analysis to measure rotational dynamics. Rigid-limit and rotational diffusion models for simulating nitroxide EPR data have been incorporated into a general non-linear least-squares procedure based on the Marq...

  20. Simultaneous measurement of glucose transport and utilization in the human brain

    Shestov, Alexander A.; Emir, Uzay E.; Kumar, Anjali; Henry, Pierre-Gilles; Seaquist, Elizabeth R.; Öz, Gülin

    2011-01-01

    Glucose is the primary fuel for brain function, and determining the kinetics of cerebral glucose transport and utilization is critical for quantifying cerebral energy metabolism. The kinetic parameters of cerebral glucose transport, KMt and Vmaxt, in humans have so far been obtained by measuring steady-state brain glucose levels by proton (1H) NMR as a function of plasma glucose levels and fitting steady-state models to these data. Extraction of the kinetic parameters for cerebral glucose tra...

  1. Integrated Microanalytical System for Simultaneous Voltammetric Measurements of Free Metal Ion Concentrations in Natural Waters

    Noël, Stéphane; Tercier-Waeber, Mary-Lou; Lin, Lin; Buffle, Jacques; Guenat, Olivier; Koudelka-Hep, Milena

    2007-01-01

    A complexing gel integrated microelectrode (CGIME) for direct measurements of free metal ion concentrations in natural waters has been developed. It is prepared by the successive deposition of microlayers of a chelating resin, an antifouling agarose gel and Hg on a 100-interconnected Ir-based microelectrode array. The trace metals of interest are in a first step accumulated on the chelating resin in proportion to their free ion concentration in solution, then released in acidic solution and d...

  2. Simultaneous Observations of pi 2 Pulsations on the Satellite and Geound-Based Measurements

    S. H. Lee

    1997-12-01

    Full Text Available We have investigated Pi2 pulsations which were observed both on ground magnetometer array and by satellites. On November 9th in 1994, pi2 pulsations appeared globally on the 190/210 magnetometer chain and Hermanus station when two satellites(EXOS-D and ETS-VI were located near the magnetic meridian of the 210 array. The local time of measurements covers form morning(LT=8.47hr to afternoon(LT=20.3hr and the bandwidth of peak frequency is found relatively small. The signals of the electric field measurement of board the EXOS-D, which is located inside the plasmasphere(L=2.35, are highly coherent with the ground-based observations with the out of phase oscillations. However, the magnetic field measurement on the ETS-VI in the outer magnetosphere(L=6.60 shows no signature of pi2 pulsations over the same time interval and the correlation with any of ground-based stations is found to be very weak, even though both satellites and magnetometer chain are located close to each other in local time. We suggest that this event may be a direct evidence of Pi2 pulsations as virtual resonant modes which are localized in the plasmasphere(Lee 1996. The results show that the cavity mode oscillations can occur in the inner magnetosphere with less spectral noise compared to the outer magnetospheric case.

  3. Simultaneous measurement of fission fragments and prompt neutrons for thermal neutron-induced fission of U-235

    Nishio, Katsuhisa; Yamamoto, Hideki; Kimura, Itsuro; Nakagome, Yoshihiro [Kyoto Univ. (Japan)

    1997-03-01

    Simultaneous measurement of fission fragments and prompt neutrons following the thermal neutron induced fission of U-235 has been performed in order to obtain the neutron multiplicity (v) and its emission energy ({eta}) against the specified mass (m{sup *}) and the total kinetic energy (TKE). The obtained value of -dv/dTKE(m{sup *}) showed a saw-tooth distribution. The average neutron energy <{eta}>(m{sup *}) had a distribution with a reflection symmetry around the half mass division. The measurement also gave the level density parameters of the specified fragment, a(m{sup *}), and this parameters showed a saw-tooth trend too. The analysis by a phenomenological description of this parameters including the shell and collective effects suggested the existence of a collective motion of the fission fragments. (author)

  4. Measurement setup for the simultaneous determination of diffusivity and Seebeck coefficient in a multi-anvil apparatus.

    Jacobsen, M K; Liu, W; Li, B

    2012-09-01

    In this paper, a high pressure setup is presented for performing simultaneous measurements of Seebeck coefficient and thermal diffusivity in multianvil apparatus for the purpose of enhancing the study of transport phenomena. Procedures for the derivation of Seebeck coefficient and thermal diffusivity/conductivity, as well as their associated sources of errors, are presented in detail, using results obtained on the filled skutterudite, Ce(0.8)Fe(3)CoSb(12,) up to 12 GPa at ambient temperature. Together with recent resistivity and sound velocity measurements in the same apparatus, these developments not only provide the necessary data for a self-consistent and complete characterization of the figure of merit of thermoelectric materials under pressure, but also serve as an important tool for furthering our knowledge of the dynamics and interplay between these transport phenomena.

  5. Magnetic field of mars from data of simultaneous measurements in the planet's magnetosphere and in the solar wind

    Dolginov, S.S.; Shkol'nikova, S.I.; Zhuzgov, L.N.

    1985-01-01

    This paper examines the parameters of the magnetic dipole of Mars according to measurements by the Mars-2 probe on February 23-24, 1972. In all components there were observed fields of marked intensity in the components; however, at the second pass of the pericenter no field of marked intensity was observed. The passage through zero and change of polarity of the radial component Y /sub m/ of the field was also revealed in the magnetogram. The results of simultaneous measurements of interplanetary magnetic fields near Mars on its day and night sides and data on the dynamic pressure of the solar wind (IMP-6) are compared. The existence of a Martian magnetic field with a magnetic moment that is an effective obstacle to the solar wind is demonstrated. It is estimated that, with the width of the polar cap of Mars ca 45 degrees, the magnetic tail of the Martian magnetosphere can reach as far as 90R /sub M/

  6. Simultaneous two-phase flow measurement of spray mixing process by means of high-speed two-color PIV

    Zhang, Ming; Xu, Min; Hung, David L S

    2014-01-01

    In this article, a novel high-speed two-color PIV optical diagnostic technique has been developed and applied to simultaneously measure the velocity flow-fields of a multi-hole spark-ignition direct injection (SIDI) fuel injector spray and its ambient gas in a high-pressure constant volume chamber. To allow for the phase discrimination between the fuel droplets and ambient gas, a special tracer-filter system was designed. Fluorescent seeding particles with Sauter mean diameter (SMD) of 4.8 µm were used to trace the gas inside the chamber. With a single high-speed Nd:YLF laser sheet (527 nm) as the incident light source, the Mie-scattering signal marked the phase of the fuel spray, while the fluorescent signal generated from the seeding particles tracked the phase of ambient gas. A high-speed camera, with an image-doubler (mounted in front of the camera lens) that divided the camera pixels into two parts focusing on the same field of view, was used to collect the Mie-scattering signal and LIF (laser induced fluorescence) signal simultaneously with two carefully selected optical filters. To accommodate the large dynamic range of velocities in the two phases (1–2 orders of magnitude difference), two separation times (dt) were introduced. This technique was successfully applied to the liquid spray and ambient gas two-phase flow measurement. The measurement accuracy was compared with those from LDV (laser Doppler velocimetry) measurement and good agreement was obtained. Ambient gas motion surrounding the fuel spray was investigated and characterized into three zones. The momentum transfer process between the fuel spray and ambient gas in each zone was analyzed. The two-phase flow interaction under various superheated conditions was investigated. A strengthened momentum transfer from the liquid spray to the ambient was observed with increased superheat degree. (paper)

  7. Simultaneous measurements of the thermospheric wind profile at three separate positions in the dusk auroral oval

    Mikkelsen, I.S.; Friis-Christensen, E.; Larsen, M.F.; Kelley, M.C.; Vickrey, J.; Meriwether, J.; Shih, P.

    1987-01-01

    On March 20, 1985, two rockets were launched from Soendre Stroemfjord, Greenland, into the dusk auroral oval. Three trimethyl aluminium trails were released to measure the neutral wind profiles between 95 and 190 km of altitude at two points separated by 190 km normal to the invariant latitude circles and at a third point separated from the first two by 300 km along the invariant latitude circles. Two barium/strontium clouds were released at 250 km of altitude, extending two of the neutral wind profiles to this altitude. In the E region the tip of the wind vector traced an ellipse as a function of increasing altitude with maximum wind speeds of 100-150 m/s in the southeastward and northwestward directions. The F region winds were southward with speeds of 100-200 m/s. The zonal wind component between 115 and 140 km of altitude had a horizontal gradient in the southeastward direction, whereas the meridional wind component at the same heights was constant over the spatial extent covered by the measurements. The authors interpret the observed E region wind field as being part of a gravity wave with a period of 3 hours as estimated from the ellipticity of the wind hodograms. The wind vectors rotated 540 degree clockwise with increasing height, indicating that the wave energy is propagating upward. The Fabry-Perot interferometer at Soendre Stroemfjord was first able to detect the F region winds 45 min after the releases and measured winds of 100-400 m/s mainly in the southeastward or antisunward direction. The geomagnetic conditions were quiet, with Kp not exceeding 2 for the 24 hours preceding the experiment. The incoherent scatter radar at Soendre Stroemfjord observed a contracted plasma convection pattern associated with positive B y and B z components of the interplanetary magnetic field

  8. Simultaneous measurements of work function and H‒ density including caesiation of a converter surface

    Cristofaro, S.; Friedl, R.; Fantz, U.

    2017-08-01

    Negative hydrogen ion sources rely on the surface conversion of neutral atomic hydrogen and positive hydrogen ions to H-. The efficiency of this process depends on the actual work function of the converter surface. By introducing caesium into the source the work function decreases, enhancing the negative ion yield. In order to study the impact of the work function on the H- surface production at similar conditions to the ones in ion sources for fusion devices like ITER and DEMO, fundamental investigations are performed in a flexible laboratory experiment. The work function of the converter surface can be absolutely measured by photoelectric effect, while a newly installed cavity ring-down spectroscopy system (CRDS) measures the H- density. The CRDS is firstly tested and characterized by investigations on H- volume production. Caesiation of a stainless steel sample is then performed in vacuum and the plasma effect on the Cs layer is investigated also for long plasma-on times. A minimum work function of (1.9±0.1) eV is reached after some minutes of plasma treatment, resulting in a reduction by a value of 0.8 eV compared to vacuum measurements. The H- density above the surface is (2.1±0.5)×1015 m-3. With further plasma exposure of the caesiated surface, the work function increases up to 3.75 eV, due to the impinging plasma particles which gradually remove the Cs layer. As a result, the H- density decreases by a factor of at least 2.

  9. Experimental study of stratified jet by simultaneous measurements of velocity and density fields

    Xu, Duo; Chen, Jun

    2012-07-01

    Stratified flows with small density difference commonly exist in geophysical and engineering applications, which often involve interaction of turbulence and buoyancy effect. A combined particle image velocimetry (PIV) and planar laser-induced fluorescence (PLIF) system is developed to measure the velocity and density fields in a dense jet discharged horizontally into a tank filled with light fluid. The illumination of PIV particles and excitation of PLIF dye are achieved by a dual-head pulsed Nd:YAG laser and two CCD cameras with a set of optical filters. The procedure for matching refractive indexes of two fluids and calibration of the combined system are presented, as well as a quantitative analysis of the measurement uncertainties. The flow structures and mixing dynamics within the central vertical plane are studied by examining the averaged parameters, turbulent kinetic energy budget, and modeling of momentum flux and buoyancy flux. At downstream, profiles of velocity and density display strong asymmetry with respect to its center. This is attributed to the fact that stable stratification reduces mixing and unstable stratification enhances mixing. In stable stratification region, most of turbulence production is consumed by mean-flow convection, whereas in unstable stratification region, turbulence production is nearly balanced by viscous dissipation. Experimental data also indicate that at downstream locations, mixing length model performs better in mixing zone of stable stratification regions, whereas in other regions, eddy viscosity/diffusivity models with static model coefficients represent effectively momentum and buoyancy flux terms. The measured turbulent Prandtl number displays strong spatial variation in the stratified jet.

  10. Human Heart Pulse Wave Responses Measured Simultaneously at Several Sensor Placements by Two MR-Compatible Fibre Optic Methods

    Teemu Myllylä

    2012-01-01

    Full Text Available This paper presents experimental measurements conducted using two noninvasive fibre optic methods for detecting heart pulse waves in the human body. Both methods can be used in conjunction with magnetic resonance imaging (MRI. For comparison, the paper also performs an MRI-compatible electrocardiogram (ECG measurement. By the simultaneous use of different measurement methods, the propagation of pressure waves generated by each heart pulse can be sensed extensively in different areas of the human body and at different depths, for example, on the chest and forehead and at the fingertip. An accurate determination of a pulse wave allows calculating the pulse transit time (PTT of a particular heart pulse in different parts of the human body. This result can then be used to estimate the pulse wave velocity of blood flow in different places. Both measurement methods are realized using magnetic resonance-compatible fibres, which makes the methods applicable to the MRI environment. One of the developed sensors is an extraordinary accelerometer sensor, while the other one is a more common sensor based on photoplethysmography. All measurements, involving several test patients, were performed both inside and outside an MRI room. Measurements inside the MRI room were conducted using a 3-Tesla strength closed MRI scanner in the Department of Diagnostic Radiology at the Oulu University Hospital.

  11. Simultaneous measurement of focal length and index of refraction of a microlens using a compound microscope

    Chollet, Franck; Ashraf, Mohammed

    2009-01-01

    The fabrication of microlenses has spurred a lot of interest and resulted in multiple techniques of fabrication in the past decade. However the metrology of these lenses has received less attention and remains a complex and time-consuming task that does not allow frequent control during development and manufacturing. We propose a simple technique based on a standard compound microscope that would allow measuring the focal length of a plano-convex lens and at the same time obtain a measure of the index of refraction of the lens material. The method relies on observing the different images of an object placed in the illumination path of the microscope. Among these images, some are created by the light going through the lens and others by its reflection on the surface. We show that with the image distance and size it is possible to retrieve the focal length and the average index of refraction of the lens material in the case of quasi-spherical lenses. The accuracy obtained by the technique is better than a few per cent and its cost is negligible as it only uses existing equipment

  12. Simultaneous measurements of thermal conductivity and electrical conductivity of micro-machined Silicon films

    Hagino, H; Kawahara, Y; Goto, A; Miyazaki, K

    2012-01-01

    The in-plane effective thermal conductivity of free-standing Si thin films with periodic micropores was measured at -100 to 0 °C. The Si thin films with micropores were prepared from silicon-on-insulator (SOI) wafers by standard microfabrication processes. The dimensions of the free-standing Si thin films were 200μm×150μm×2 μm, with staggered 4 μm pores having an average pitch of 4 mm. The Si thin film serves both as a heater and thermometer. The average temperature rise of the thin film is a function of its in-plane thermal conductivity. The effective thermal conductivity was calculated using a simple one-dimensional heat conduction model. The measured thermal conductivity was much lower than that expected based on classical model evaluations. A significant phonon size effect was observed even in the microsized structures, and the mean free path for phonons is very long even at the room temperature.

  13. Solar UV exposures measured simultaneously to all arbitrarily oriented leaves on a plant.

    Parisi, Alfio V; Schouten, Peter; Downs, Nathan J; Turner, Joanna

    2010-05-03

    The possible ramifications of climate change include the influence it has upon the amount of cloud cover in the atmosphere. Clouds cause significant variation in the solar UV radiation reaching the earth's surface and in turn the amount incident on ecosystems. The consequences of changes in solar UV radiation delivered to ecosystems due to climate change may be significant and should be investigated. Plants are an integral part of the world wide ecological balance, and research has shown they are affected by variations in solar UV radiation. Therefore research into the influence of solar UV radiation on plants is of particular significance. However, this requires a means of obtaining detailed information on the solar UV radiation received by plants. This research describes a newly developed dosimetric technique employed to gather information on solar UV radiation incident to the leaves of plants in combination with the measurement of spectral irradiances in order to provide an accurate method of collecting detailed information on the solar UV radiation affecting the canopy and lower leaf layers of individual plants. Variations in the measurements take into account the inclination and orientation of each leaf investigated, as well as the influence of shading by other leaves in the plant canopy. Copyright 2010 Elsevier B.V. All rights reserved.

  14. Airborne Lidar for Simultaneous Measurement of Column CO2 and Water Vapor in the Atmosphere

    Singh, Upendra N.; Petros, Mulugeta; Refaat, Tamer F.; Antill, Charles W.; Remus, Ruben; Yu, Jirong

    2016-01-01

    The 2-micron wavelength region is suitable for atmospheric carbon dioxide (CO2) measurements due to the existence of distinct absorption feathers for the gas at this particular wavelength. For more than 20 years, researchers at NASA Langley Research Center (LaRC) have developed several high-energy and high repetition rate 2-micron pulsed lasers. This paper will provide status and details of an airborne 2-micron triple-pulse integrated path differential absorption (IPDA) lidar. The development of this active optical remote sensing IPDA instrument is targeted for measuring both CO2 and water vapor (H2O) in the atmosphere from an airborne platform. This presentation will focus on the advancement of the 2-micron triple-pulse IPDA lidar development. Updates on the state-of-the-art triple-pulse laser transmitter will be presented including the status of seed laser locking, wavelength control, receiver telescope, detection system and data acquisition. Future plans for the IPDA lidar system for ground integration, testing and flight validation will also be presented.

  15. A high-throughput mass spectrometry assay to simultaneously measure intact insulin and C-peptide.

    Taylor, Steven W; Clarke, Nigel J; Chen, Zhaohui; McPhaul, Michael J

    2016-04-01

    Measurements of fasting levels of insulin and C-peptide are useful in documenting insulin resistance and may help predict development of diabetes mellitus. However, the specific insulin and C-peptide levels associated with specific degrees of insulin resistance have not been defined, owing to marked variability among immunoassays and lack of standardization. Herein, we describe a multiplexed liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for intact insulin and C-peptide. Insulin and C-peptide were enriched from patient sera using monoclonal antibodies immobilized on magnetic beads and processed on a robotic liquid handler. Eluted peptides were analyzed by LC-MS/MS. Bovine insulin and a stable isotopically-labeled (13C/15N) C-peptide were utilized as internal standards. The assay had an analytical measurement range of 3 to 320 μIU/ml (18 to 1920 pmol/l) for insulin and 0.11 to 27.2 ng/ml (36 to 9006 pmol/l) for C-peptide. Intra- and inter-day assay variation was less than 11% for both peptides. Of the 5 insulin analogs commonly prescribed to treat diabetes, only the recombinant drug insulin lispro caused significant interference for the determination of endogenous insulin. There were no observed interferences for C-peptide. We developed and validated a high-throughput, quantitative, multiplexed LC-MS/MS assay for intact insulin and C-peptide. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Extravascular lung water: its measurement by simultaneous pulmonary and aortic sampling and iterative convolution

    Giuntini, C.; Fazio, F.

    1975-01-01

    The inadequacy of the apparent distribution volume of THO during the first passage dilution curve (a) to account for the total lung water in in-vitro measurements in dogs and (b) to measure any increase in lung water, even in patients with obvious clinical pulmonary oedema, prompted the present investigation. Tritiated water, THO, as diffusible indicator, and human serum albumin labelled with 131 I, ALB, as intravascular tracer, are injected into the superior vena cava at the junction with the right atrium. In order to clear the aortic blood samples of recirculation, the recirculating tracers must be determined. This is accomplished by pulmonary artery sampling. Iterative convolution of the pulmonary artery dilution curves with suitable test functions eventually yields products of convolution that fit well the corresponding aortic dilution curves of THO and ALB. The test functions that yield the best fit are taken to represent the frequency functions of the transit time from pulmonary artery to aorta of THO and ALB, respectively. By applying the same procedure of iterative convolution to these frequency functions, we obtain the dilution curve of THO in the extravascular lung space. As a result of this analysis: (a) forward extrapolation is less subject to systematic errors such as overestimation of the mean transit time of ALB, i.e. of the tracer that recirculates more; and (b) the distribution volume of THO can be better defined since the dilution of THO in the extravascular lung space may be followed beyond the point of recirculation. The results indicate that both in normal subjects and in patients with left ventricular insufficiency the computed dilution curves of THO in the extravascular lung space have a long tail which is more pronounced in the patients. These findings suggest the existence in the lungs of extravascular water pools that are slowly exchanging with pulmonary water flow. This may depend both on inhomogeneities of perfusion, with lack of it at

  17. Simultaneous blood pressure measurement in both arms in hypertensive and nonhypertensive adult patients.

    Fonseca-Reyes, Salvador; Forsyth-MacQuarrie, Avril M; García de Alba-García, Javier Eduardo

    2012-08-01

    When blood pressure (BP) is taken for the first time, it should be measured in both arms; follow-up measurements should be taken in the arm with the highest BP. However, in clinical practice, this recommendation is rarely followed. Identify the degree of differences in BP between the right and the left arm in individuals with normal and high BP. We measured BP in 111 hypertensive and 80 normotensive patients in both arms at the same time using identical Omron HEM 725 CIC automatic sphygmomanometers. The devices were then switched to the other arm and another set of readings was taken. The absolute and relative difference in BP between arms was calculated from the average of these two readings. We categorized differences as at least 5, at least 10, and at least 20 mmHg for systolic blood pressure/diastolic blood pressure (SBP/DBP). The BP was higher in the right arm, with no statistical significance. The relative differences were also not significant: SBP 1.1±7.1 and DBP 0.21±5.0. However, the absolute differences were significant at an individual level, with a systolic difference of 5.4±4.8 mmHg and a diastolic difference of 3.9 ±3.2 mmHg. The percentages of absolute SBP/DBP differences more than 5 mmHg (21.4%/20.4%) and more than 10 mmHg (15.7%/4.7%) were considerable. The range of arm differences was clinically significant; in hypertensives, the SBP/DBP was -13.2 to +15/-9.2 to +9.6 mmHg and in nonhypertensives it was -12.9 to +15.6/-9.7 to +10.1 mmHg. Although on average there was no clinically significant relative difference between arms, absolute differences at an individual level were often clinically significant. Failure to determine interarm BP differences will lead to erroneous clinical decisions.

  18. Simultaneous specimen current and time-dependent cathodoluminescence measurements on gallium nitride

    Campo, E. M., E-mail: e.campo@bangor.ac.uk; Hopkins, L. [School of Electronic Engineering, Bangor University, Gwynedd LL57 1UT (United Kingdom); Pophristic, M. [Department of Chemistry and Biochemistry, University of the Science, Philadelphia, Pennsylvania 19104 (United States); Ferguson, I. T. [Department of Electrical and Computer Engineering, Missouri University of Science and Technology, Rolla, Missouri 65409 (United States)

    2016-06-28

    Time-dependent cathodoluminescence (CL) and specimen current (SC) are monitored to evaluate trapping behavior and evolution of charge storage. Examination of CL and SC suggests that the near band edge emission in GaN is reduced primarily by the activation of traps upon irradiation, and Gallium vacancies are prime candidates. At the steady state, measurement of the stored charge by empiric-analytical methods suggests that all available traps within the interaction volume have been filled, and that additional charge is being stored interstitially, necessarily beyond the interaction volume. Once established, the space charge region is responsible for the steady state CL emission and, prior to build up, it is responsible for the generation of diffusion currents. Since the non-recombination effects resulting from diffusion currents that develop early on are analogous to those leading to device failure upon aging, this study is fundamental toward a holistic insight into optical properties in GaN.

  19. Differential rigor development in red and white muscle revealed by simultaneous measurement of tension and stiffness.

    Kobayashi, Masahiko; Takemori, Shigeru; Yamaguchi, Maki

    2004-02-10

    Based on the molecular mechanism of rigor mortis, we have proposed that stiffness (elastic modulus evaluated with tension response against minute length perturbations) can be a suitable index of post-mortem rigidity in skeletal muscle. To trace the developmental process of rigor mortis, we measured stiffness and tension in both red and white rat skeletal muscle kept in liquid paraffin at 37 and 25 degrees C. White muscle (in which type IIB fibres predominate) developed stiffness and tension significantly more slowly than red muscle, except for soleus red muscle at 25 degrees C, which showed disproportionately slow rigor development. In each of the examined muscles, stiffness and tension developed more slowly at 25 degrees C than at 37 degrees C. In each specimen, tension always reached its maximum level earlier than stiffness, and then decreased more rapidly and markedly than stiffness. These phenomena may account for the sequential progress of rigor mortis in human cadavers.

  20. Simultaneous scanning tunneling microscopy and synchrotron X-ray measurements in a gas environment.

    Mom, Rik V; Onderwaater, Willem G; Rost, Marcel J; Jankowski, Maciej; Wenzel, Sabine; Jacobse, Leon; Alkemade, Paul F A; Vandalon, Vincent; van Spronsen, Matthijs A; van Weeren, Matthijs; Crama, Bert; van der Tuijn, Peter; Felici, Roberto; Kessels, Wilhelmus M M; Carlà, Francesco; Frenken, Joost W M; Groot, Irene M N

    2017-11-01

    A combined X-ray and scanning tunneling microscopy (STM) instrument is presented that enables the local detection of X-ray absorption on surfaces in a gas environment. To suppress the collection of ion currents generated in the gas phase, coaxially shielded STM tips were used. The conductive outer shield of the coaxial tips can be biased to deflect ions away from the tip core. When tunneling, the X-ray-induced current is separated from the regular, 'topographic' tunneling current using a novel high-speed separation scheme. We demonstrate the capabilities of the instrument by measuring the local X-ray-induced current on Au(1 1 1) in 800 mbar Ar. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Results of induced atmosphere measurements from the Apollo program. [possible effects of the induced environment in the vicinity of manned spacecraft on future manned laboratory experiments

    Naumann, R. J.

    1974-01-01

    Experiments on Apollo missions 15, 16, and 17 were utilized in an attempt to learn about the induced environment in the vicinity of manned spacecraft. Photographic sequences were examined to obtain scattered light data from the spacecraft-generated particulates during quiescence periods and after liquid dumps. The results allowed estimates of the obscuration factor and the clearing times after dumps. It was found that the clearing times were substantially longer than anticipated. The mass spectrometer detected a high molecular flux in lunar orbit which was induced by the spacecraft. It is shown that this is most likely caused by small ice crystals being continually produced in lunar orbit. Other data from the ultraviolet spectrometer and the stellar camera are also analyzed, and estimated values or upper limits are placed on the total scattering background, the size and number of particles generated, the velocity range, and the column density.

  2. Surface current dynamics under sea breeze conditions observed by simultaneous HF radar, ADCP and drifter measurements

    Sentchev, Alexei; Forget, Philippe; Fraunié, Philippe

    2017-04-01

    Ocean surface boundary layer dynamics off the southern coast of France in the NW Mediterranean is investigated by using velocity observations by high-frequency (HF) radars, surface drifting buoys and a downward-looking drifting acoustic Doppler current profiler (ADCP). The analysis confirms that velocities measured by HF radars correspond to those observed by an ADCP at the effective depth z f = k -1, where k is wavenumber of the radio wave emitted by the radar. The radials provided by the radars were in a very good agreement with in situ measurements, with the relative errors of 1 and 9 % and root mean square (RMS) differences of 0.02 and 0.04 m/s for monostatic and bistatic radar, respectively. The total radar-based velocities appeared to be slightly underestimated in magnitude and somewhat biased in direction. At the end of the survey period, the difference in the surface current direction, based on HF radar and ADCP data, attained 10°. It was demonstrated that the surface boundary layer dynamics cannot be reconstructed successfully without taking into the account velocity variation with depth. A significant misalignment of ˜30° caused by the sea breeze was documented between the HF radar (HFR-derived) surface current and the background current. It was also found that the ocean response to a moderate wind forcing was confined to the 4-m-thick upper layer. The respective Ekman current attained the maximum value of 0.15 m/s, and the current rotation was found to be lagging the wind by approximately 40 min, with the current vector direction being 15-20° to the left of the wind. The range of velocity variability due to wind forcing was found comparable with the magnitude of the background current variability.

  3. Spacecraft Tests of General Relativity

    Anderson, John D.

    1997-01-01

    Current spacecraft tests of general relativity depend on coherent radio tracking referred to atomic frequency standards at the ground stations. This paper addresses the possibility of improved tests using essentially the current system, but with the added possibility of a space-borne atomic clock. Outside of the obvious measurement of the gravitational frequency shift of the spacecraft clock, a successor to the suborbital flight of a Scout D rocket in 1976 (GP-A Project), other metric tests would benefit most directly by a possible improved sensitivity for the reduced coherent data. For purposes of illustration, two possible missions are discussed. The first is a highly eccentric Earth orbiter, and the second a solar-conjunction experiment to measure the Shapiro time delay using coherent Doppler data instead of the conventional ranging modulation.

  4. Simultaneous measurement of monocomponent droplet temperature/refractive index, size and evaporation rate with phase rainbow refractometry

    Wu, Yingchun; Crua, Cyril; Li, Haipeng; Saengkaew, Sawitree; Mädler, Lutz; Wu, Xuecheng; Gréhan, Gérard

    2018-07-01

    The accurate measurements of droplet temperature, size and evaporation rate are of great importance to characterize the heat and mass transfer during evaporation/condensation processes. The nanoscale size change of a micron-sized droplet exactly describes its transient mass transfer, but is difficult to measure because it is smaller than the resolutions of current size measurement techniques. The Phase Rainbow Refractometry (PRR) technique is developed and applied to measure droplet temperature, size and transient size changes and thereafter evaporation rate simultaneously. The measurement principle of PRR is theoretically derived, and it reveals that the phase shift of the time-resolved ripple structures linearly depends on, and can directly yield, nano-scale size changes of droplets. The PRR technique is first verified through the simulation of rainbows of droplets with changing size, and results show that PRR can precisely measure droplet refractive index, absolute size, as well as size change with absolute and relative errors within several nanometers and 0.6%, respectively, and thus PRR permits accurate measurements of transient droplet evaporation rates. The evaporations of flowing single n-nonane droplet and mono-dispersed n-heptane droplet stream are investigated by two PRR systems with a high speed linear CCD and a low speed array CCD, respectively. Their transient evaporation rates are experimentally determined and quantitatively agree well with the theoretical values predicted by classical Maxwell and Stefan-Fuchs models. With the demonstration of evaporation rate measurement of monocomponent droplet in this work, PRR is an ideal tool for measurements of transient droplet evaporation/condensation processes, and can be extended to multicomponent droplets in a wide range of industrially-relevant applications.

  5. Tumour oxygen dynamics measured simultaneously by near-infrared spectroscopy and 19F magnetic resonance imaging in rats

    Xia Mengna; Kodibagkar, Vikram; Liu Hanli; Mason, Ralph P

    2006-01-01

    Simultaneous near-infrared spectroscopy (NIRS) and magnetic resonance imaging (MRI) were used to investigate the correlation between tumour vascular oxygenation and tissue oxygen tension dynamics in rat breast 13762NF tumours with respect to hyperoxic gas breathing. NIRS directly detected global variations in the oxygenated haemoglobin concentration (Δ[HbO 2 ]) within tumours and oxygen tension (pO 2 ) maps were achieved using 19 F MRI of the reporter molecule hexafluorobenzene. Multiple correlations were examined between rates and magnitudes of vascular (Δ[HbO 2 ]) and tissue (pO 2 ) responses. Significant correlations were found between response to oxygen and carbogen breathing using either modality. Comparison of results for the two methods showed a correlation between the vascular perfusion rate ratio and the mean pO 2 values (R 2 > 0.7). The initial rates of increase of Δ[HbO 2 ] and the slope of dynamic pO 2 response, d(pO 2 )/dt, of well-oxygenated voxels in response to hyperoxic challenge were also correlated. These results demonstrate the feasibility of simultaneous measurements using NIRS and MRI. As expected, the rate of pO 2 response to oxygen is primarily dependent upon the well perfused rather than poorly perfused vasculature

  6. Simultaneous identification of optical constants and PSD of spherical particles by multi-wavelength scattering-transmittance measurement

    Zhang, Jun-You; Qi, Hong; Ren, Ya-Tao; Ruan, Li-Ming

    2018-04-01

    An accurate and stable identification technique is developed to retrieve the optical constants and particle size distributions (PSDs) of particle system simultaneously from the multi-wavelength scattering-transmittance signals by using the improved quantum particle swarm optimization algorithm. The Mie theory are selected to calculate the directional laser intensity scattered by particles and the spectral collimated transmittance. The sensitivity and objective function distribution analysis were conducted to evaluate the mathematical properties (i.e. ill-posedness and multimodality) of the inverse problems under three different optical signals combinations (i.e. the single-wavelength multi-angle light scattering signal, the single-wavelength multi-angle light scattering and spectral transmittance signal, and the multi-angle light scattering and spectral transmittance signal). It was found the best global convergence performance can be obtained by using the multi-wavelength scattering-transmittance signals. Meanwhile, the present technique have been tested under different Gaussian measurement noise to prove its feasibility in a large solution space. All the results show that the inverse technique by using multi-wavelength scattering-transmittance signals is effective and suitable for retrieving the optical complex refractive indices and PSD of particle system simultaneously.

  7. Optical fiber-based full Mueller polarimeter for endoscopic imaging using a two-wavelength simultaneous measurement method.

    Vizet, Jérémy; Manhas, Sandeep; Tran, Jacqueline; Validire, Pierre; Benali, Abdelali; Garcia-Caurel, Enric; Pierangelo, Angelo; De Martino, Antonello; Pagnoux, Dominique

    2016-07-01

    This paper reports a technique based on spectrally differential measurement for determining the full Mueller matrix of a biological sample through an optical fiber. In this technique, two close wavelengths were used simultaneously, one for characterizing the fiber and the other for characterizing the assembly of fiber and sample. The characteristics of the fiber measured at one wavelength were used to decouple its contribution from the measurement on the assembly of fiber and sample and then to extract sample Mueller matrix at the second wavelength. The proof of concept was experimentally validated by measuring polarimetric parameters of various calibrated optical components through the optical fiber. Then, polarimetric images of histological cuts of human colon tissues were measured, and retardance, diattenuation, and orientation of the main axes of fibrillar regions were displayed. Finally, these images were successfully compared with images obtained by a free space Mueller microscope. As the reported method does not use any moving component, it offers attractive integration possibilities with an endoscopic probe.

  8. A nine-electrode probe for simultaneous measurement of all terms in the ideal radial Ohm's law

    Si, Jiahe; Wang, Zhehui

    2006-01-01

    A Nine-Electrode Probe (NEP) has been developed for simultaneous measurement of all terms in the ideal Ohm's law E+UxB=0 in the radial (r) direction in cylindrical geometry, where E is the electric field, U is the plasma flow velocity, and B is the magnetic field. The probe consists of two pairs of directional Langmuir probes ('Mach' probes) to measure the axial (z) and azimuthal (θ) plasma flows, two pairs of floating Langmuir probes at different radial positions to measure the radial electric field, and two B-dot coils to measure the axial and azimuthal magnetic field. The measurement is performed in the Flowing Magnetized Plasma (FMP) experiment. Two flow patterns are identified in the FMP experiment by the NEP. The peak-to-peak values of radial electric field fluctuation is 1.5-4 times of the mean values. Comparisons of UxBvertical bar r and E r show that E r + UxBvertical bar r is not zero within some periods of discharge. This deviation suggests non-ideal effects in Ohm's law can not be neglected

  9. Estimation of aerosol particle number distribution with Kalman Filtering – Part 2: Simultaneous use of DMPS, APS and nephelometer measurements

    T. Viskari

    2012-12-01

    Full Text Available Extended Kalman Filter (EKF is used to estimate particle size distributions from observations. The focus here is on the practical application of EKF to simultaneously merge information from different types of experimental instruments. Every 10 min, the prior state estimate is updated with size-segregating measurements from Differential Mobility Particle Sizer (DMPS and Aerodynamic Particle Sizer (APS as well as integrating measurements from a nephelometer. Error covariances are approximate in our EKF implementation. The observation operator assumes a constant particle density and refractive index. The state estimates are compared to particle size distributions that are a composite of DMPS and APS measurements. The impact of each instrument on the size distribution estimate is studied. Kalman Filtering of DMPS and APS yielded a temporally consistent state estimate. This state estimate is continuous over the overlapping size range of DMPS and APS. Inclusion of the integrating measurements further reduces the effect of measurement noise. Even with the present approximations, EKF is shown to be a very promising method to estimate particle size distribution with observations from different types of instruments.

  10. Simultaneous measurement of neutrons and fission fragments of thermal neutron fission of U-233

    Itsuro Kimura; Katsuhisa Nishio; Yoshihiro Nakagome

    2000-01-01

    The multiplicity and the energy of prompt neutrons from the fragments for 233 U(n th , f) were measured as functions of fragment mass and total kinetic energy. Average neutron energy against the fragment mass showed a nearly symmetric distribution about the half mass division with two valleys at 98 and 145 u. The slope of the neutron multiplicity with total kinetic energy depended on the fragment mass and showed the minimum at about 130 u. The obtained neutron data were applied to determine the total excitation energy of the system, and the resulting value in the typical asymmetric fission lied between 22 and 25 MeV. The excitation energy agreed with that determined by subtracting the total kinetic energy from the Q-value within 1 MeV, thus satisfied the energy conservation. In the symmetric fission, where the mass yield was drastically suppresses, the total excitation energy is significantly large and reaches to about 40 MeV, suggesting that fragment pairs are preferentially formed in a compact configuration at the scission point [ru

  11. Simultaneous vitality and DNA-fragmentation measurement in spermatozoa of smokers and non-smokers.

    De Bantel, A; Fleury-Feith, J; Poirot, C; Berthaut, I; Garcin, C; Landais, P; Ravel, C

    2015-03-01

    Because cigarette smoke is a powerful ROS producer, we hypothesized that the spermatozoa of smokers would be more at risk of having increased DNA fragmentation than spermatozoa of non-smoking men. A cross-sectional study was performed on consenting smokers and non-smokers, consulting in an infertility clinic for routine sperm analysis. The application of a novel TUNEL assay coupled to a vitality marker, LIVE/DEAD®, allowed both DNA fragmentation and viability measurement within spermatozoa of participants to be analyzed by flow cytometry. The coupled vitality-DNA fragmentation analysis revealed that non-smokers and smokers, respectively presented medians of 3.6% [0.6-36.8] and 3.3% [0.9-9.6] DNA fragmented spermatozoa among the living spermatozoa population (P > 0.05). No deleterious effect of smoking on spermatozoa was found in our study. More studies concerning potential mutagenic capacities of cigarette smoke on spermatozoa are necessary. In addition, the coupled vitality-DNA fragmentation analysis may orient Assisted Reproductive Technology teams when confronted with patients having a high percentage of DNA-fragmented living spermatozoa. © 2014 International Clinical Cytometry Society.

  12. Simultaneous reflectometry and interferometry for measuring thin-film thickness and curvature

    Arends, A. A.; Germain, T. M.; Owens, J. F.; Putnam, S. A.

    2018-05-01

    A coupled reflectometer-interferometer apparatus is described for thin-film thickness and curvature characterization in the three-phase contact line region of evaporating fluids. Validation reflectometry studies are provided for Au, Ge, and Si substrates and thin-film coatings of SiO2 and hydrogel/Ti/SiO2. For interferometry, liquid/air and solid/air interferences are studied, where the solid/air samples consisted of glass/air/glass wedges, cylindrical lenses, and molded polydimethylsiloxane lenses. The liquid/air studies are based on steady-state evaporation experiments of water and isooctane on Si and SiO2/Ti/SiO2 wafers. The liquid thin-films facilitate characterization of both (i) the nano-scale thickness of the absorbed fluid layer and (ii) the macro-scale liquid meniscus thickness, curvature, and curvature gradient profiles. For our validation studies with commercial lenses, the apparatus is shown to measure thickness profiles within 4.1%-10.8% error.

  13. Geomagnetic control of mesospheric nitric oxide concentration from simultaneous D and F region ionization measurements

    Pradhan, S.N.; Shirke, J.S.

    1978-01-01

    Investigations are made of D-region electron density profiles derived from 'partial reflection' measurements over a low latitude station (Ahmedabad) during a year of low solar activity. The index relating the electron density with the solar zenith angle is found to increase towards lower zenith angles suggesting both diurnal and seasonal variations in the Nitric oxide concentration. A close correlation is also found between the electron density at 80 km and the maximum ionization density in the F region above. This is interpreted as due to concomitant variation of a sizeable fraction of the Nitric oxide concentration in the mesosphere and lower thermosphere with the overhead F region ionization. A simplified global model is presented for the mesospheric Nitric oxide concentration based on the morphological features of F region and the relationship existing between the ionization levels in F and D regions. Many observed features of the D region ionization including the solar zenith angle dependence, latitudinal and geomagnetic anomaly and long term variability are explained on the basis of this model

  14. Direct simultaneous measurement of intraglottal geometry and velocity fields in excised larynges.

    Khosla, Sid; Oren, Liran; Ying, Jun; Gutmark, Ephraim

    2014-04-01

    Current theories regarding the mechanisms of phonation are based on assumptions about the aerodynamics between the vocal folds during the closing phase of vocal fold vibration. However, many of these fundamental assumptions have never been validated in a tissue model. In this study, the main objective was to determine the aerodynamics (velocity fields) and the geometry of the medial surface of the vocal folds during the closing phase of vibration. The main hypothesis is that intraglottal vortices are produced during vocal fold closing when the glottal duct has a divergent shape and that these vortices are associated with negative pressures. Experiments using seven excised canine larynges. The particle imaging velocimetry (PIV) method was used to determine the velocity fields at low, mid-, and high subglottal pressures for each larynx. Modifications were made to previously described PIV methodology to allow the measurement of both the intraglottal velocity fields and the position of the medial aspects of the vocal fold. At relatively low subglottal pressures, little to no intraglottal vortices were seen. At mid- and high subglottal pressures, the flow separation vortices occurred and produced maximum negative pressures, relative to atmospheric, of -2.6 to -14.6 cm H2 O. Possible physiological and surgical implications are discussed. Intraglottal vortices produce significant negative pressures at mid- and high subglottal pressures. These vortices may be important in increasing maximum flow declination rate and acoustic intensity. N/A. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  15. A microfluidic device for simultaneous measurement of viscosity and flow rate of blood in a complex fluidic network.

    Jun Kang, Yang; Yeom, Eunseop; Lee, Sang-Joon

    2013-01-01

    Blood viscosity has been considered as one of important biophysical parameters for effectively monitoring variations in physiological and pathological conditions of circulatory disorders. Standard previous methods make it difficult to evaluate variations of blood viscosity under cardiopulmonary bypass procedures or hemodialysis. In this study, we proposed a unique microfluidic device for simultaneously measuring viscosity and flow rate of whole blood circulating in a complex fluidic network including a rat, a reservoir, a pinch valve, and a peristaltic pump. To demonstrate the proposed method, a twin-shaped microfluidic device, which is composed of two half-circular chambers, two side channels with multiple indicating channels, and one bridge channel, was carefully designed. Based on the microfluidic device, three sequential flow controls were applied to identify viscosity and flow rate of blood, with label-free and sensorless detection. The half-circular chamber was employed to achieve mechanical membrane compliance for flow stabilization in the microfluidic device. To quantify the effect of flow stabilization on flow fluctuations, a formula of pulsation index (PI) was analytically derived using a discrete fluidic circuit model. Using the PI formula, the time constant contributed by the half-circular chamber is estimated to be 8 s. Furthermore, flow fluctuations resulting from the peristaltic pumps are completely removed, especially under periodic flow conditions within short periods (T viscosity with respect to varying flow rate conditions [(a) known blood flow rate via a syringe pump, (b) unknown blood flow rate via a peristaltic pump]. As a result, the flow rate and viscosity of blood can be simultaneously measured with satisfactory accuracy. In addition, the proposed method was successfully applied to identify the viscosity of rat blood, which circulates in a complex fluidic network. These observations confirm that the proposed method can be used for

  16. Fractionated Spacecraft Architectures Seeding Study

    Mathieu, Charlotte; Weigel, Annalisa

    2006-01-01

    .... Models were developed from a customer-centric perspective to assess different fractionated spacecraft architectures relative to traditional spacecraft architectures using multi-attribute analysis...

  17. Spacecraft momentum control systems

    Leve, Frederick A; Peck, Mason A

    2015-01-01

    The goal of this book is to serve both as a practical technical reference and a resource for gaining a fuller understanding of the state of the art of spacecraft momentum control systems, specifically looking at control moment gyroscopes (CMGs). As a result, the subject matter includes theory, technology, and systems engineering. The authors combine material on system-level architecture of spacecraft that feature momentum-control systems with material about the momentum-control hardware and software. This also encompasses material on the theoretical and algorithmic approaches to the control of space vehicles with CMGs. In essence, CMGs are the attitude-control actuators that make contemporary highly agile spacecraft possible. The rise of commercial Earth imaging, the advances in privately built spacecraft (including small satellites), and the growing popularity of the subject matter in academic circles over the past decade argues that now is the time for an in-depth treatment of the topic. CMGs are augmented ...

  18. Spacecraft Material Outgassing Data

    National Aeronautics and Space Administration — This compilation of outgassing data of materials intended for spacecraft use were obtained at the Goddard Space Flight Center (GSFC), utilizing equipment developed...

  19. Spacecraft Fire Safety Demonstration

    National Aeronautics and Space Administration — The objective of the Spacecraft Fire Safety Demonstration project is to develop and conduct large-scale fire safety experiments on an International Space Station...

  20. Quick spacecraft charging primer

    Larsen, Brian Arthur

    2014-01-01

    This is a presentation in PDF format which is a quick spacecraft charging primer, meant to be used for program training. It goes into detail about charging physics, RBSP examples, and how to identify charging.

  1. Simultaneous measurement of hormone release and secretagogue binding by individual pituitary cells

    Smith, P.F.; Neill, J.D.

    1987-01-01

    The quantitative relationship between receptor binding and hormone secretion at the single-cell level was investigated in the present study by combining a reverse hemolytic plaque assay for measurement of luteinizing hormone (LH) secretion from individual pituitary cells with an autoradiographic assay of 125 I-labeled gonadontropin-releasing hormone (GnRH) agonist binding to the same cells. In the plaque assay, LH secretion induces complement-mediated lysis of the LH-antibody-coated erythrocytes around the gonadotropes, resulting in areas of lysis (plaques). LH release from individual gonadotropes was quantified by comparing radioimmunoassayable LH release to hemolytic area in similarly treated cohort groups of cells; plaque area was linearly related to the amount of LH secreted. Receptor autoradiography was performed using 125 I-labeled GnRH-A (a superagonist analog of GnRH) both as the ligand and as the stimulant for LH release in the plaque assay. The grains appeared to represent specific and high-affinity receptors for GnRH because (i) no pituitary cells other than gonadotropes bound the labeled ligand and (ii) grain development was progressively inhibited by coincubation with increasing doses of unlabeled GnRH-A. The authors conclude that GnRH receptor number for any individual gonadotrope is a weak determinant of the amount of LH it can secrete; nevertheless, full occupancy of all its GnRH receptors is required for any gonadotrope to reach its full LH-secretory capacity. Apparently the levels of other factors comprising the steps along the secretory pathway determine the secretory capacity of an individual cell

  2. Deployable Brake for Spacecraft

    Rausch, J. R.; Maloney, J. W.

    1987-01-01

    Aerodynamic shield that could be opened and closed proposed. Report presents concepts for deployable aerodynamic brake. Brake used by spacecraft returning from high orbit to low orbit around Earth. Spacecraft makes grazing passes through atmosphere to slow down by drag of brake. Brake flexible shield made of woven metal or ceramic withstanding high temperatures created by air friction. Stored until needed, then deployed by set of struts.

  3. Parameterization of strombolian explosions: constraint from simultaneous physical and geophysical measurements (Invited)

    gurioli, L.; Harris, A. J.

    2013-12-01

    Stromboli, and other volcanoes like it, are to plot in the strombolian fields of deposit-based classifications. We also quenched a number of bombs soon explosion at Stromboli. This enabled us to quantify the degassing history and rheology of the magma(s) resident in the shallow, near-surface, system. The different textural facies observed in these bombs showed that fresh magma, mingled with partially or completely degassed, oxidized, re-crystallized, evolved and high viscosity magma, was ejected. The degassed magma appears to sit at the top of the conduit, playing only a passive role in the explosive process. Our best model, is that the degassed, oxidized magma forms a plug, or rheologically defined layer, at the top of the conduit, through which the fresh magma bursts. Integration of geophysical measurements with sample analyses, indicates that popular (bubble-bursting) models may not fit this case, thus also changeling the model-based definition of this eruption type.

  4. Simultaneous planar measurements of soot structure and velocity fields in a turbulent lifted jet flame at 3 kHz

    Köhler, M.; Boxx, I.; Geigle, K. P.; Meier, W.

    2011-05-01

    We describe a newly developed combustion diagnostic for the simultaneous planar imaging of soot structure and velocity fields in a highly sooting, lifted turbulent jet flame at 3000 frames per second, or two orders of magnitude faster than "conventional" laser imaging systems. This diagnostic uses short pulse duration (8 ns), frequency-doubled, diode-pumped solid state (DPSS) lasers to excite laser-induced incandescence (LII) at 3 kHz, which is then imaged onto a high framerate CMOS camera. A second (dual-cavity) DPSS laser and CMOS camera form the basis of a particle image velocity (PIV) system used to acquire 2-component velocity field in the flame. The LII response curve (measured in a laminar propane diffusion flame) is presented and the combined diagnostics then applied in a heavily sooting lifted turbulent jet flame. The potential challenges and rewards of application of this combined imaging technique at high speeds are discussed.

  5. Examining diseased states in a scaled-up vocal fold model using simultaneous temporally resolved DPIV and pressure measurements

    Rogers, Dylan; Wei, Nathaniel; Ringenber, Hunter; Krane, Michael; Wei, Timothy

    2017-11-01

    This study builds on the parallel presentation of Ringenberg, et al. (APS-DFD 2017) involving simultaneous, temporally and spatially resolved flow and pressure measurements in a scaled-up vocal fold model. In this talk, data from experiments replicating characteristics of diseased vocal folds are presented. This begins with vocal folds that do not fully close and continues with asymmetric oscillations. Data are compared to symmetric, i.e. `healthy', oscillatory motions presented in the companion talk. Having pressure and flow data for individual as well as phase averaged oscillations for these diseased cases highlights the potential for aeroacoustic analysis in this complex system. Supported by NIH Grant No. 2R01 DC005642-11.

  6. Simultaneous measurements of auroral particles and electric currents by a rocket-borne instrument system - Introductory remarks

    Anderson, H. R.; Cloutier, P. A.

    1975-01-01

    A rocket-borne experiment package has been designed to obtain simultaneous in situ measurements of the pitch angle distributions and energy spectra of primary auroral particles, the flux of neutral hydrogen at auroral energies, the electric currents flowing in the vicinity of the auroral arc as determined from vector magnetic data, and the modulation of precipitating electrons in the frequency range 0.5-10 MHz. The experiment package was launched by a Nike-Tomahawk rocket from Poker Flat, Alaska, at 0722 UT on Feb. 25, 1972, over a bright auroral band. This paper is intended to serve as an introduction to the detailed discussion of results given in the companion papers. As such it includes a brief review of the general problem, a discussion of the rocket instrumentation, a delineation of the auroral and geomagnetic conditions at the time of launch, and comments on the overall payload performance.

  7. Simultaneous measurements of auroral particles and electric currents by a rocket-borne instrument system: introductory remarks

    Anderson, H.R.; Cloutier, P.A.

    1975-01-01

    A rocket-borne experiment package has been designed to obtain simultaneous in situ measurements of the pitch angle distribution and energy spectra of primary auroral particles, the flux of neutral hydrogen at auroral energies, the electric currents flowing in the vicinity of the auroral arc as determined from vector magnetic data, and the modulation of precipitating electrons in the frequency range 0.5-10 MHz. The experiment package was launched by a Nike-Tomahawk rocket from Poker Flat, Alaska, at 0722 UT on February 25, 1972, over a bright auroral band. This paper is intended to serve as an introduction to the detailed discussion of results given in the companion papers. As such it includes a brief review of the general problem, a discussion of the rocket instrumentation, a delineation of the auroral and geomagnetic conditions at the time of launch, and comments on the overall payload performance

  8. Simultaneous measurement of the surface temperature and the release of atomic sodium from a burning black liquor droplet

    Saw, Woei L.; Nathan, Graham J. [Centre for Energy Technology, The University of Adelaide, SA 5006 (Australia); School of Mechanical Engineering, The University of Adelaide (Australia); Ashman, Peter J.; Alwahabi, Zeyad T. [Centre for Energy Technology, The University of Adelaide, SA 5006 (Australia); School of Chemical Engineering, The University of Adelaide (Australia); Hupa, Mikko [Process Chemistry Centre, Aabo Akademi, Biskopsgatan 8 FI-20500 Aabo (Finland)

    2010-04-15

    Simultaneous measurement of the concentration of released atomic sodium, swelling, surface and internal temperature of a burning black liquor droplet under a fuel lean and rich condition has been demonstrated. Two-dimensional two-colour optical pyrometry was employed to determine the distribution of surface temperature and swelling of a burning black liquor droplet while planar laser-induced fluorescence (PLIF) was used to assess the temporal release of atomic sodium. The key findings of these studies are: (i) the concentration of atomic sodium released during the drying and devolatilisation stages was found to be correlated with the external surface area; and (ii) the insignificant presence of atomic sodium during the char consumption stage shows that sodium release is suppressed by the lower temperature and by the high CO{sub 2} content in and around the particle. (author)

  9. Simultaneous measurements of formaldehyde and nitrous acid in dews and gas phase in the atmosphere of Santiago, Chile

    Rubio, María A.; Lissi, Eduardo; Villena, Guillermo; Elshorbany, Y. F.; Kleffmann, Jörg; Kurtenbach, Ralf; Wiesen, Peter

    2009-12-01

    The amounts of formaldehyde and nitrous acid (HONO) in gas phase and dews of Santiago de Chile were simultaneously measured. Formaldehyde concentrations values in the liquid phase (dews) correlate fairly well with those in the gaseous phase and are even higher than those expected from gas-dew equilibrium. On the other hand, nitrite concentrations in dews were considerably smaller (ca. 15 times) than those expected from the gas-phase concentrations. This under-saturation is attributed to diffusion limitations due to the relatively large HONO solubility. In agreement with this, under-saturation increases with the rate of dew formation and the pH of the collected waters, factors that should increase the rate of gas to liquid HONO transfer required to reach equilibrium.

  10. The Simultaneous measurement of serum testosterone and 5α-dihydrotestosterone by gas chromatography-mass spectrometry (GC-MS).

    Kannenberg, Frank; Fobker, Manfred; Schulte, Erhard; Pierściński, Grzegorz; Kelsch, Reinhard; Zitzmann, Michael; Nofer, Jerzy-Roch; Schüring, Andreas N

    2018-01-01

    Simultaneous measurement of testosterone (T) and 5α-dihydrotestosterone (DHT) is important for diagnosing androgen deficiency states and hyperandrogenism in males and females, respectively. However, immunoassays used for T and DHT determination suffer from inadequate specificity and sensitivity, while tandem mass spectrometry is expensive and demanding in use. We developed a selective gas chromatography-mass spectrometry (GC-MS) method for parallel T and DHT measurement. The assay showed a linear response up to 46.5nmol/L, intra- and interassay imprecision and inaccuracy 90% for both analytes. The limit of quantitation was 0.117nmol/L for T and 0.168nmol/L for DHT. Comparison with immunoassays revealed good agreement for T in males, but a bias in favour of immunoassays at low concentrations for T in females and DHT in both sexes. We established reference ranges for T and DHT and suggest interval partitioning for T according to age in men and menstrual cycle in women. Assay validation in a clinical setting suggests that measuring DHT or T/DHT ratio may help identify patients with polycystic ovary syndrome. We developed a selective, simple and inexpensive GC-MS method for parallel measurement of T and DHT with potential use in the clinical laboratory. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Capability of simultaneous Rayleigh LiDAR and O2 airglow measurements in exploring the short period wave characteristics

    Taori, Alok; Raghunath, Karnam; Jayaraman, Achuthan

    We use combination of simultaneous measurements made with Rayleigh lidar and O2 airglow monitoring to improve lidar investigation capability to cover a higher altitude range. We feed instantaneous O2 airglow temperatures instead the model values at the top altitude for subsequent integration method of temperature retrieval using Rayleigh lidar back scattered signals. Using this method, errors in the lidar temperature estimates converges at higher altitudes indicating better altitude coverage compared to regular methods where model temperatures are used instead of real-time measurements. This improvement enables the measurements of short period waves at upper mesospheric altitudes (~90 km). With two case studies, we show that above 60 km the few short period wave amplitude drastically increases while, some of the short period wave show either damping or saturation. We claim that by using such combined measurements, a significant and cost effective progress can be made in the understanding of short period wave processes which are important for the coupling across the different atmospheric regions.

  12. Two Years of Simultaneous K(sub a)-Band Measurements: Goldstone, CA; White Sands, NM; and Guam, USA

    Acosta, Roberto J.; Zemba, M.; Morse, J.; Nessel, J.

    2012-01-01

    In order to statistically characterize the effect of the Earth's atmosphere on Ka-Band links, site test interferometers (STIs) have been deployed at three of NASA s operational sites to directly measure each site's tropospheric phase stability and rain attenuation. These STIs are composed of two antennas on a short baseline (less than 1km) that observe the same unmodulated beacon signal broadcast from a geostationary satellite (e.g., Anik F2). The STIs are used to measure the differential phase between the two received signals as well as the individual signal attenuation at each terminal. There are currently three NASA sites utilizing STIs; the Goldstone Deep Space Communications Complex near Barstow, California; the White Sands Complex in Las Cruces, New Mexico; and the Guam Remote Ground Terminal on the island of Guam. The first two sites are both located in desert regions that have highly similar climates in terms of their seasonal temperatures, average humidity, and annual rain fall (the primary factors in determining phase stability). In contrast, Guam is in a tropical region with drastically higher annual rainfall and humidity. Five station years of data have been collected in Goldstone, three in White Sands, and two in Guam, yielding two years of simultaneous data collection across all three sites. During this period of simultaneous data collection, the root-mean-square (RMS) of the time delay fluctuations stayed under 2.40 picoseconds for 90% of the time in Goldstone, under 2.07 picoseconds for 90% of the time in White Sands, and under 10.13 picoseconds for 90% of the time in Guam. For the 99th percentile, the statistics were 6.32 ps, 6.03 ps, and 24.85 ps, respectively. These values, as well as various other site quality characteristics, will be used to determine the suitability of these sites for NASA s future communication services at Ka-Band.

  13. Simultaneous in vivo comparison of water-filled and air-filled pressure measurement catheters: Implications for good urodynamic practice.

    Gammie, A; Abrams, P; Bevan, W; Ellis-Jones, J; Gray, J; Hassine, A; Williams, J; Hashim, H

    2016-11-01

    This study aimed to evaluate whether the pressure readings obtained from air-filled catheters (AFCs) are the same as the readings from simultaneously inserted water-filled catheters (WFCs). It also aimed to make any possible recommendations for the use of AFCs to conform to International Continence Society (ICS) Good Urodynamic Practices (GUP). Female patients undergoing urodynamic studies in a single center had water-filled and air-filled catheters simultaneously measuring abdominal and intravesical pressure during filling with saline and during voiding. The pressures recorded by each system at each event during the test were compared using paired t-test and Bland-Altman analyses. 62 patients were recruited, of whom 51 had pressures that could be compared during filling, and 23 during voiding. On average, the pressures measured by the two systems were not significantly different during filling and at maximum flow, but the values for a given patient were found to differ by up to 10 cmH 2 O. This study shows that AFCs and WFCs cannot be assumed to register equal values of pressure. It has further shown that even when the p det readings are compared with their value at the start of a test, a divergence of values of up to 10 cmH 2 O remains. If AFCs are used, care must be taken to compensate for any p det variations that occur during patient movement. Before AFCs are adopted, new normal values for resting pressures need to be developed to allow good quality AFC pressure readings to be made. Neurourol. Urodynam. 35:926-933, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  14. Simultaneous measurement of temperature, stress, and electric field in GaN HEMTs with micro-Raman spectroscopy.

    Bagnall, Kevin R; Moore, Elizabeth A; Badescu, Stefan C; Zhang, Lenan; Wang, Evelyn N

    2017-11-01

    As semiconductor devices based on silicon reach their intrinsic material limits, compound semiconductors, such as gallium nitride (GaN), are gaining increasing interest for high performance, solid-state transistor applications. Unfortunately, higher voltage, current, and/or power levels in GaN high electron mobility transistors (HEMTs) often result in elevated device temperatures, degraded performance, and shorter lifetimes. Although micro-Raman spectroscopy has become one of the most popular techniques for measuring localized temperature rise in GaN HEMTs for reliability assessment, decoupling the effects of temperature, mechanical stress, and electric field on the optical phonon frequencies measured by micro-Raman spectroscopy is challenging. In this work, we demonstrate the simultaneous measurement of temperature rise, inverse piezoelectric stress, thermoelastic stress, and vertical electric field via micro-Raman spectroscopy from the shifts of the E 2 (high), A 1 longitudinal optical (LO), and E 2 (low) optical phonon frequencies in wurtzite GaN. We also validate experimentally that the pinched OFF state as the unpowered reference accurately measures the temperature rise by removing the effect of the vertical electric field on the Raman spectrum and that the vertical electric field is approximately the same whether the channel is open or closed. Our experimental results are in good quantitative agreement with a 3D electro-thermo-mechanical model of the HEMT we tested and indicate that the GaN buffer acts as a semi-insulating, p-type material due to the presence of deep acceptors in the lower half of the bandgap. This implementation of micro-Raman spectroscopy offers an exciting opportunity to simultaneously probe thermal, mechanical, and electrical phenomena in semiconductor devices under bias, providing unique insight into the complex physics that describes device behavior and reliability. Although GaN HEMTs have been specifically used in this study to

  15. Simultaneous measurement of temperature, stress, and electric field in GaN HEMTs with micro-Raman spectroscopy

    Bagnall, Kevin R.; Moore, Elizabeth A.; Badescu, Stefan C.; Zhang, Lenan; Wang, Evelyn N.

    2017-11-01

    As semiconductor devices based on silicon reach their intrinsic material limits, compound semiconductors, such as gallium nitride (GaN), are gaining increasing interest for high performance, solid-state transistor applications. Unfortunately, higher voltage, current, and/or power levels in GaN high electron mobility transistors (HEMTs) often result in elevated device temperatures, degraded performance, and shorter lifetimes. Although micro-Raman spectroscopy has become one of the most popular techniques for measuring localized temperature rise in GaN HEMTs for reliability assessment, decoupling the effects of temperature, mechanical stress, and electric field on the optical phonon frequencies measured by micro-Raman spectroscopy is challenging. In this work, we demonstrate the simultaneous measurement of temperature rise, inverse piezoelectric stress, thermoelastic stress, and vertical electric field via micro-Raman spectroscopy from the shifts of the E2 (high), A1 longitudinal optical (LO), and E2 (low) optical phonon frequencies in wurtzite GaN. We also validate experimentally that the pinched OFF state as the unpowered reference accurately measures the temperature rise by removing the effect of the vertical electric field on the Raman spectrum and that the vertical electric field is approximately the same whether the channel is open or closed. Our experimental results are in good quantitative agreement with a 3D electro-thermo-mechanical model of the HEMT we tested and indicate that the GaN buffer acts as a semi-insulating, p-type material due to the presence of deep acceptors in the lower half of the bandgap. This implementation of micro-Raman spectroscopy offers an exciting opportunity to simultaneously probe thermal, mechanical, and electrical phenomena in semiconductor devices under bias, providing unique insight into the complex physics that describes device behavior and reliability. Although GaN HEMTs have been specifically used in this study to

  16. Simultaneous measurements of thickness and temperature profile in a wavy liquid film falling freely on a heating wall

    Lyu, T.; Mudawar, I.

    1990-01-01

    This paper reports on a technique for measuring the thickness of liquid films that was developed and tested. The feasibility of this technique was demonstrated in stagnant liquid films as well as in liquid jets. A procedure for in-situ calibration of the thickness probe was developed, allowing the adaptation of the probe to measurements of wavy liquid films. The thickness probe was constructed from a platinum-rhodium wire that was stretched across the film. A constant DC current was supplied through the probe wire, and film thickness was determined from variations in the probe voltage drop resulting from the large differences in the electrical resistances of the wetted and unwetted segments of the wire. Unlike electrical admittance thickness probes, the new probe did not require dissolving an electrolyte in the liquid, making the new probe well suited to studies involving sensible heating of a film of pure dielectric liquid that is in direct contact with a current- carrying wall. Also presented is a composite probe that facilitated simultaneous measurements of temperature profile across a wavy liquid film and film thickness. Experimental results demonstrate a strong influence of waviness on liquid temperature in a film of deionized water falling freely on the outside wall of a vertical, electrically heated tube for film Reynolds numbers smaller than 10,000

  17. Simultaneous Retrieval of Aerosol and Surface Optical Properties from Combined Airborne- and Ground-Based Direct and Diffuse Radiometric Measurements

    Gatebe, C. K.; Dubovik, O.; King, M. D.; Sinyuk, A.

    2010-01-01

    This paper presents a new method for simultaneously retrieving aerosol and surface reflectance properties from combined airborne and ground-based direct and diffuse radiometric measurements. The method is based on the standard Aerosol Robotic Network (AERONET) method for retrieving aerosol size distribution, complex index of refraction, and single scattering albedo, but modified to retrieve aerosol properties in two layers, below and above the aircraft, and parameters on surface optical properties from combined datasets (Cloud Absorption Radiometer (CAR) and AERONET data). A key advantage of this method is the inversion of all available spectral and angular data at the same time, while accounting for the influence of noise in the inversion procedure using statistical optimization. The wide spectral (0.34-2.30 m) and angular range (180 ) of the CAR instrument, combined with observations from an AERONET sunphotometer, provide sufficient measurement constraints for characterizing aerosol and surface properties with minimal assumptions. The robustness of the method was tested on observations made during four different field campaigns: (a) the Southern African Regional Science Initiative 2000 over Mongu, Zambia, (b) the Intercontinental Transport Experiment-Phase B over Mexico City, Mexico (c) Cloud and Land Surface Interaction Campaign over the Atmospheric Radiation Measurement (ARM) Central Facility, Oklahoma, USA, and (d) the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) over Elson Lagoon in Barrow, Alaska, USA. The four areas are dominated by different surface characteristics and aerosol types, and therefore provide good test cases for the new inversion method.

  18. Simultaneous Water Vapor and Dry Air Optical Path Length Measurements and Compensation with the Large Binocular Telescope Interferometer

    Defrere, D.; Hinz, P.; Downey, E.; Boehm, M.; Danchi, W. C.; Durney, O.; Ertel, S.; Hill, J. M.; Hoffmann, W. F.; Mennesson, B.; hide

    2016-01-01

    The Large Binocular Telescope Interferometer uses a near-infrared camera to measure the optical path length variations between the two AO-corrected apertures and provide high-angular resolution observations for all its science channels (1.5-13 microns). There is however a wavelength dependent component to the atmospheric turbulence, which can introduce optical path length errors when observing at a wavelength different from that of the fringe sensing camera. Water vapor in particular is highly dispersive and its effect must be taken into account for high-precision infrared interferometric observations as described previously for VLTI/MIDI or the Keck Interferometer Nuller. In this paper, we describe the new sensing approach that has been developed at the LBT to measure and monitor the optical path length fluctuations due to dry air and water vapor separately. After reviewing the current performance of the system for dry air seeing compensation, we present simultaneous H-, K-, and N-band observations that illustrate the feasibility of our feed forward approach to stabilize the path length fluctuations seen by the LBTI nuller uses a near-infrared camera to measure the optical path length variations between the two AO-corrected apertures and provide high-angular resolution observations for all its science channels (1.5-13 microns). There is however a wavelength dependent component to the atmospheric turbulence, which can introduce optical path length errors when observing at a wavelength different from that of the fringe sensing camera. Water vapor in particular is highly dispersive and its effect must be taken into account for high-precision infrared interferometric observations as described previously for VLTI MIDI or the Keck Interferometer Nuller. In this paper, we describe the new sensing approach that has been developed at the LBT to measure and monitor the optical path length fluctuations due to dry air and water vapor separately. After reviewing the current

  19. Mechanical Design of Spacecraft

    1962-01-01

    In the spring of 1962, engineers from the Engineering Mechanics Division of the Jet Propulsion Laboratory gave a series of lectures on spacecraft design at the Engineering Design seminars conducted at the California Institute of Technology. Several of these lectures were subsequently given at Stanford University as part of the Space Technology seminar series sponsored by the Department of Aeronautics and Astronautics. Presented here are notes taken from these lectures. The lectures were conceived with the intent of providing the audience with a glimpse of the activities of a few mechanical engineers who are involved in designing, building, and testing spacecraft. Engineering courses generally consist of heavily idealized problems in order to allow the more efficient teaching of mathematical technique. Students, therefore, receive a somewhat limited exposure to actual engineering problems, which are typified by more unknowns than equations. For this reason it was considered valuable to demonstrate some of the problems faced by spacecraft designers, the processes used to arrive at solutions, and the interactions between the engineer and the remainder of the organization in which he is constrained to operate. These lecture notes are not so much a compilation of sophisticated techniques of analysis as they are a collection of examples of spacecraft hardware and associated problems. They will be of interest not so much to the experienced spacecraft designer as to those who wonder what part the mechanical engineer plays in an effort such as the exploration of space.

  20. Transient plane source (tps) sensors for simultaneous measurements of thermal conductivity and thermal diffusivity of insulators, fluids and conductors

    Maqsood, Asghari; Anis-ur-Rehman, M.

    2013-12-01

    Thermal conductivity and thermal diffusivity are two important physical properties for designing any food engineering processes1. The knowledge of thermal properties of the elements, compounds and different materials in many industrial applications is a requirement for their final functionality. Transient plane source (tps) sensors are reported2 to be useful for the simultaneous measurement of thermal conductivity, thermal diffusivity and volumetric heat capacity of insulators, conductor liquids3 and high-TC superconductors4. The tps-sensor consists of a resistive element in the shape of double spiral made of 10 micrometer thick Ni-foils covered on both sides with 25 micrometer thick Kapton. This sensor acts both as a heat source and a resistance thermometer for recording the time dependent temperature increase. From the knowledge of the temperature co-efficient of the metal spiral, the temperature increase of the sensor can be determined precisely by placing the sensor in between two surfaces of the same material under test. This temperature increase is then related to the thermal conductivity, thermal diffusivity and volumetric heat capacity by simple relations2,5. The tps-sensor has been used to measure thermal conductivities from 0.001 Wm-1K-1to 600 Wm-1K-1 and temperature ranges covered from 77K- 1000K. This talk gives the design, advantages and limitations of the tpl-sensor along with its applications to the measurementof thermal properties in a variety of materials.

  1. Transient plane source (tps) sensors for simultaneous measurements of thermal conductivity and thermal diffusivity of insulators, fluids and conductors

    Maqsood, Asghari; Anis-ur-Rehman, M

    2013-01-01

    Thermal conductivity and thermal diffusivity are two important physical properties for designing any food engineering processes 1 . The knowledge of thermal properties of the elements, compounds and different materials in many industrial applications is a requirement for their final functionality. Transient plane source (tps) sensors are reported 2 to be useful for the simultaneous measurement of thermal conductivity, thermal diffusivity and volumetric heat capacity of insulators, conductor liquids 3 and high-T C superconductors 4 . The tps-sensor consists of a resistive element in the shape of double spiral made of 10 micrometer thick Ni-foils covered on both sides with 25 micrometer thick Kapton. This sensor acts both as a heat source and a resistance thermometer for recording the time dependent temperature increase. From the knowledge of the temperature co-efficient of the metal spiral, the temperature increase of the sensor can be determined precisely by placing the sensor in between two surfaces of the same material under test. This temperature increase is then related to the thermal conductivity, thermal diffusivity and volumetric heat capacity by simple relations 2,5 . The tps-sensor has been used to measure thermal conductivities from 0.001 Wm −1 K −1 to 600 Wm −1 K −1 and temperature ranges covered from 77K– 1000K. This talk gives the design, advantages and limitations of the tpl-sensor along with its applications to the measurementof thermal properties in a variety of materials

  2. Dynamic Measurement of Tumor Vascular Permeability and Perfusion using a Hybrid System for Simultaneous Magnetic Resonance and Fluorescence Imaging.

    Ren, Wuwei; Elmer, Andreas; Buehlmann, David; Augath, Mark-Aurel; Vats, Divya; Ripoll, Jorge; Rudin, Markus

    2016-04-01

    Assessing tumor vascular features including permeability and perfusion is essential for diagnostic and therapeutic purposes. The aim of this study was to compare fluorescence and magnetic resonance imaging (MRI)-based vascular readouts in subcutaneously implanted tumors in mice by simultaneous dynamic measurement of tracer uptake using a hybrid fluorescence molecular tomography (FMT)/MRI system. Vascular permeability was measured using a mixture of extravascular imaging agents, GdDOTA and the dye Cy5.5, and perfusion using a mixture of intravascular agents, Endorem and a fluorescent probe (Angiosense). Dynamic fluorescence reflectance imaging (dFRI) was integrated into the hybrid system for high temporal resolution. Excellent correspondence between uptake curves of Cy5.5/GdDOTA and Endorem/Angiosense has been found with correlation coefficients R > 0.98. The two modalities revealed good agreement regarding permeability coefficients and centers-of-gravity of the imaging agent distribution. The FMT/dFRI protocol presented is able to accurately map physiological processes and poses an attractive alternative to MRI for characterizing tumor neoangiogenesis.

  3. First simultaneous measurement of fission and gamma probabilities of 237U and 239Np via surrogate reactions

    Marini P.

    2016-01-01

    Full Text Available Fission and gamma decay probabilities of 237U and 239Np have been measured, for the first time simultaneously in dedicated experiments, via the surrogate reactions 238U(3He, 4He and 238U(3He,d, respectively. While a good agreement between our data and neutron-induced data is found for fission probabilities, gamma decay probabilities are several times higher than the corresponding neutron-induced data for each studied nucleus. We study the role of the different spin distributions populated in the surrogate and neutron-induced reactions. The compound nucleus spin distribution populated in the surrogate reaction is extracted from the measured gamma-decay probabilities, and used as input parameter in the statistical model to predict fission probabilities to be compared to our data. A strong disagreement between our data and the prediction is obtained. Preliminary results from an additional dedicated experiment confirm the observed discrepancies, indicating the need of a better understanding of the formation and decay processes of the compound nucleus.

  4. Single peak parameters technique for simultaneous measurements: Spectrophotometric sequential injection determination of Fe(II) and Fe(III).

    Kozak, J; Paluch, J; Węgrzecka, A; Kozak, M; Wieczorek, M; Kochana, J; Kościelniak, P

    2016-02-01

    Spectrophotometric sequential injection system (SI) is proposed to automate the method of simultaneous determination of Fe(II) and Fe(III) on the basis of parameters of a single peak. In the developed SI system, sample and mixture of reagents (1,10-phenanthroline and sulfosalicylic acid) are introduced into a vessel, where in an acid environment (pH≅3) appropriate compounds of Fe(II) and Fe(III) with 1,10-phenanthroline and sulfosalicylic acid are formed, respectively. Then, in turn, air, sample, EDTA and sample again, are introduced into a holding coil. After the flow reversal, a segment of air is removed from the system by an additional valve and as EDTA replaces sulfosalicylic acid forming a more stable colorless compound with Fe(III), a complex signal is registered. Measurements are performed at wavelength 530 nm. The absorbance measured at minimum of the negative peak and the area or the absorbance measured at maximum of the signal can be used as measures corresponding to Fe(II) and Fe(III) concentrations, respectively. The time of the peak registration is about 2 min. Two-component calibration has been applied to analysis. Fe(II) and Fe(III) can be determined within the concentration ranges of 0.04-4.00 and 0.1-5.00 mg L(-1), with precision less than 2.8% and 1.7% (RSD), respectively and accuracy better than 7% (RE). The detection limit is 0.04 and 0.09 mg L(-1) for Fe(II) and Fe(III), respectively. The method was applied to analysis of artesian water samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Simultaneous measurement of quantum yield ratio and absorption ratio between acceptor and donor by linearly unmixing excitation-emission spectra.

    Zhang, C; Lin, F; DU, M; Qu, W; Mai, Z; Qu, J; Chen, T

    2018-02-13

    Quantum yield ratio (Q A /Q D ) and absorption ratio (K A /K D ) in all excitation wavelengths used between acceptor and donor are indispensable to quantitative fluorescence resonance energy transfer (FRET) measurement based on linearly unmixing excitation-emission spectra (ExEm-spFRET). We here describe an approach to simultaneously measure Q A /Q D and K A /K D values by linearly unmixing the excitation-emission spectra of at least two different donor-acceptor tandem constructs with unknown FRET efficiency. To measure the Q A /Q D and K A /K D values of Venus (V) to Cerulean (C), we used a wide-field fluorescence microscope to image living HepG2 cells separately expressing each of four different C-V tandem constructs at different emission wavelengths with 435 nm and 470 nm excitation respectively to obtain the corresponding excitation-emission spectrum (S DA ). Every S DA was linearly unmixed into the contributions (weights) of three excitation-emission spectra of donor (W D ) and acceptor (W A ) as well as donor-acceptor sensitisation (W S ). Plot of W S /W D versus W A /W D for the four C-V plasmids from at least 40 cells indicated a linear relationship with 1.865 of absolute intercept (Q A /Q D ) and 0.273 of the reciprocal of slope (K A /K D ), which was validated by quantitative FRET measurements adopting 1.865 of Q A /Q D and 0.273 of K A /K D for C32V, C5V, CVC and VCV constructs respectively in living HepG2 cells. © 2018 The Authors Journal of Microscopy © 2018 Royal Microscopical Society.

  6. Simultaneous measurements of acetylene and soot during the pyrolysis of ethylene and benzene in a shock tube

    KC, Utsav

    2016-10-12

    Acetylene is one of the most important precursors of soot and contributes to soot growth by the hydrogen-abstraction acetylene-addition (HACA) mechanism. In this work, we undertake time-resolved simultaneous measurements of acetylene and soot behind reflected shock waves at temperatures of 1600-2200. K and pressures of 3-5. bar. Acetylene mole fraction time-histories are measured from the absorption of a quantum-cascade laser operating around 13.6. μm. The soot volume fraction, particle size and number densities are calculated from the extinction and scattering of a cw Nd:Yag laser at 532. nm. Acetylene and soot are generated from the pyrolysis of 1% benzene in argon, 2.35% ethylene in argon, and binary mixtures of ethylene with propane/methane in argon. We note that acetylene time-histories exhibit a two-stage growth during the pyrolysis of benzene, which can be correlated to the initial rapid increase of soot volume fraction and a later plateauing. In comparison to ethylene pyrolysis, the pyrolysis of benzene results in larger values of the soot volume fraction, particle diameter and number density. We compare the measured data against the values simulated using the method-of-moments routine in Chemkin-Pro and a detailed PAH mechanism based on KM2 [1] and AramcoMech 1.3 [2]. Large discrepancies are observed between the measured and predicted values of the soot parameters. The data obtained from our experiments may assist future validation and development of soot mechanisms.

  7. Submarines, spacecraft and exhaled breath.

    Pleil, Joachim D; Hansel, Armin

    2012-03-01

    -term plans for their analytical tools, in this case to take breath analysis away from the large complex instruments in the laboratory to the outpatient clinic and eventually to the home care market. Similarly, for environmental and public health research, it is always desirable to have easily operated and deployable instruments that can be taken to the field, rather than bringing numerous subjects to a central laboratory. Bio-monitoring. Although the SAMAP community is much more focused on air rather than breath measurement, this is changing because of the realization that longer deployment times (on submarines and spacecraft) will affect more than just acute health. To monitor longer-term health outcomes, there is a great deal of commonality between our respective research communities. Any instrument that monitors for contaminants in environmental air could certainly be adapted to breath analysis for assessing exposures and health state. Instruments that simultaneously provide rapid response and high specificity to a broad range of analytes, such as those based on optical spectroscopy and mass spectrometry, are particularly valued. The path forward We found the SAMAP meeting to be a worthwhile experience, largely from the discovery that another high-tech community exists with similar needs as the IABR community. Some collaboration could be fruitful for us; we suggest that the IABR community stay in contact with SAMAP in the future and attempt to attend each other's meetings if possible. SAMAP meetings tend to run on a two year cycle and so the next one has not yet been announced. We will let the IABR community know when the next meeting is scheduled, and will certainly make the SAMAP people aware of IABR meetings and the Journal of Breath Research. This article has been subjected to EPA Agency review and approved for publication. Statements do not necessarily reflect official Agency policy.

  8. Preliminary Results from the Joint Russian and US Field Test: Measurement of Sensorimotor and Cardiovascular Responses Immediately Following Landing of the Soyuz Spacecraft

    Reschke, M. F.; Kozlovskaya, I. B.; Tomilovskaya, E. S.; Bloomberg, J. J.; Platts, S. H.; Rukavishnikov, I. V.; Fomina, E. V.; Stenger, M. B.; Lee, S. M. C.; Wood, S. J.; hide

    2013-01-01

    Ongoing collaborative research efforts between NASA's Neuroscience and Cardiovascular Laboratories, and the Institute of Biomedical Problems' (IBMP) Sensory-Motor and Countermeasures Laboratories have been measuring functional sensorimotor, cardiovascular and strength responses following bed rest, dry immersion, short duration (Space Shuttle) and long duration (Mir and International Space Station) space flights. While the unloading paradigms associated with dry immersion and bed rest have do serve as acceptable flight analogs, testing of crew responses following the long duration flights does not begin until a minimum of 24 hours after landing. As a result it is not possible to estimate the nonlinear trend of the early (testing at the time of landing and before the flight crews have left the landing site. By joint agreement this research effort has been identified as the functional Field Test (FT). For practical reasons the FT has been divided into two phases: the full FT and a preliminary pilot version (PFT) of the FT that is reduced in both length and scope. The primary goal of this research is to determine functional abilities in long duration space flight crews beginning as soon after landing as possible (test in conjunction with postural ataxia testing. In addition to the immediate post-landing collection of data for the full FT, postflight data will be acquired at a minimum of one to three more other times within the 24 hr following landing and continue until functional sensorimotor and cardiovascular responses have returned to preflight normative values. The PFT represents a single trial run comprised of jointly agreed tests from the full FT and relies heavily on IBMP's Sensory-Motor and Countermeasures Laboratories for content, and implementation. The PFT is currently scheduled for the September 2013 landing of the Soyuz spacecraft (34S). Testing will include: (1) a sit-to-stand test, (2) recovery from a fall where the crewmember begins in the prone

  9. Revamping Spacecraft Operational Intelligence

    Hwang, Victor

    2012-01-01

    The EPOXI flight mission has been testing a new commercial system, Splunk, which employs data mining techniques to organize and present spacecraft telemetry data in a high-level manner. By abstracting away data-source specific details, Splunk unifies arbitrary data formats into one uniform system. This not only reduces the time and effort for retrieving relevant data, but it also increases operational visibility by allowing a spacecraft team to correlate data across many different sources. Splunk's scalable architecture coupled with its graphing modules also provide a solid toolset for generating data visualizations and building real-time applications such as browser-based telemetry displays.

  10. Dips spacecraft integration issues

    Determan, W.R.; Harty, R.B.

    1988-01-01

    The Department of Energy, in cooperation with the Department of Defense, has recently initiated the dynamic isotope power system (DIPS) demonstration program. DIPS is designed to provide 1 to 10 kW of electrical power for future military spacecraft. One of the near-term missions considered as a potential application for DIPS was the boost surveillance and tracking system (BSTS). A brief review and summary of the reasons behind a selection of DIPS for BSTS-type missions is presented. Many of these are directly related to spacecraft integration issues; these issues will be reviewed in the areas of system safety, operations, survivability, reliability, and autonomy

  11. Objective and subjective measures of simultaneous vs sequential bilateral cochlear implants in adults : A randomized clinical trial

    Kraaijenga, Véronique J.C.; Ramakers, Geerte G.J.; Smulders, Yvette E.; Van Zon, Alice; Stegeman, Inge; Smit, Adriana L.; Stokroos, Robert J.; Hendrice, Nadia; Free, Rolien H.; Maat, Bert; Frijns, Johan H M; Briaire, Jeroen J; Mylanus, Emmanuel A M; Huinck, Wendy J.; van Zanten, Gijsbert A.; Grolman, Wilko

    2017-01-01

    IMPORTANCE: To date, no randomized clinical trial on the comparison between simultaneous and sequential bilateral cochlear implants (BiCIs) has been performed.  OBJECTIVE: To investigate the hearing capabilities and the self-reported benefits of simultaneous BiCIs compared with those of sequential

  12. Objective and Subjective Measures of Simultaneous vs Sequential Bilateral Cochlear Implants in Adults: A Randomized Clinical Trial

    Kraaijenga, V.J.; Ramakers, G.G.; Smulders, Y.E.; Zon, A. van; Stegeman, I.; Smit, A.L.; Stokroos, R.J.; Hendrice, N.; Free, R.H.; Maat, B.; Frijns, J.H.; Briaire, J.J.; Mylanus, E.A.M.; Huinck, W.J.; Zanten, G.A.; Grolman, W.

    2017-01-01

    Importance: To date, no randomized clinical trial on the comparison between simultaneous and sequential bilateral cochlear implants (BiCIs) has been performed. Objective: To investigate the hearing capabilities and the self-reported benefits of simultaneous BiCIs compared with those of sequential

  13. Measuring perfusion and bioenergetics simultaneously in mouse skeletal muscle: a multi-parametric functional-NMR approach

    Baligand, C.; Wary, C.; Menard, J.C.; Giacomini, E.; Carlier, P.G.; Baligand, C.; Wary, C.; Menard, J.C.; Hogrel, J.Y.; Carlier, P.G.; Hogrel, J.Y.

    2011-01-01

    A totally noninvasive set-up was developed for comprehensive NMR evaluation of mouse skeletal muscle function in vivo. Dynamic pulsed arterial spin labeling-NMRI perfusion and blood oxygenation level-dependent (BOLD) signal measurements were interleaved with 31 P NMRS to measure both vascular response and oxidative capacities during stimulated exercise and subsequent recovery. Force output was recorded with a dedicated ergometer. Twelve exercise bouts were performed. The perfusion, BOLD signal, pH and force-time integral were obtained from mouse legs for each exercise. All reached a steady state after the second exercise, justifying the pointwise summation of the last 10 exercises to compensate for the limited 31 P signal. In this way, a high temporal resolution of 2.5 s was achieved to provide a time constant for phosphocreatine (PCr) recovery (tPCr). The higher signal-to-noise ratio improved the precision of τ(PCr) measurement [coefficient of variation (CV)1/416.5% vs CV1/449.2% for a single exercise at a resolution of 30 s]. Inter-animal summation confirmed that τ(PCr) was stable at steady state, but shorter (89.3W8.6 s) than after the first exercise (148 s, p≤0.05). This novel experimental approach provides an assessment of muscle vascular response simultaneously to energetic function in vivo. Its pertinence was illustrated by observing the establishment of a metabolic steady state. This comprehensive tool offers new perspectives for the study of muscle pathology in mice models. (authors)

  14. Continuous and simultaneous measurements of precipitation and vapor isotopes over two monsoon seasons during 2016-2017 in Singapore

    Jackisch, D.; He, S.; Ong, M. R.; Goodkin, N.

    2017-12-01

    Water isotopes are important tracers of climate dynamics and their measurement can provide valuable insights into the relationship between isotopes and atmospheric parameters and overall convective activities. While most studies provide data on daily or even monthly time scales, high-temporal in-situ stable isotope measurements are scarce, especially in the tropics. In this study, we presented δ18O and δ2H values in precipitation and vapor continuously and simultaneously measured using laser spectroscopy in Singapore during the 2016/2017 Northeast (NE) Asian monsoon and 2017 Southwest (SW) Asian monsoon. We found that δ-values of precipitation and vapor exhibit quite different patterns during individual events, although there is a significant correlation between the δ-values of precipitation and of vapor. δ-values in precipitation during individual precipitation events show a distinct V-shape pattern, with the lowest isotope values observed in the middle of the event. However, isotopes in water vapor mostly show an L-shape and are characterized by a gradual decrease with the onset of rainfall. The difference in δ-values of precipitation and vapor is generally constant during the early stage of the events but gradually increases near the end. It is likely that vapor and precipitation are closer to equilibrium at the early stage of a rain event, but diverge at the later stages. This divergence can be largely attributed to the evaporation of raindrops. We notice a frequent drop in d-excess of precipitation, whereas d-excess in vapor increases. In addition, a significant correlation exists between outgoing longwave radiation (OLR) and isotopes in both precipitation and vapor, suggesting an influence of regional convective activity.

  15. Simultaneous measurement of total Estradiol and Testosterone in human serum by isotope dilution liquid chromatography tandem mass spectrometry

    Zhou, Hui; Wang, Yuesong; Gatcombe, Matthew; Farris, Jacob; Botelho, Julianne C.; Caudill, Samuel P.; Vesper, Hubert W.

    2017-01-01

    Reliable measurement of total testosterone and estradiol is critical for their use as biomarkers of hormone related disorders in patient care and translation research. We developed and validated a mass spectrometry method to simultaneously quantify these analytes in human serum without chemical derivatization. Serum is equilibrated with isotopic internal standards and treated with acidic buffer to release hormones from their binding proteins. Lipids are isolated and polar impurities are removed by two serial liquid-liquid extraction steps. Total testosterone and estradiol are measured using liquid chromatography tandem mass spectrometry (LC-MS/MS) in combination of positive and negative electrospray ionization modes. The method shows broad analytical measurement range for both testosterone 0.03–48.5 nM (0.75–1400 ng/dL) and estradiol 11.0–5138 pM (2.99–1400 pg/mL) and excellent agreement with certified reference materials (mean bias less than 2.1% to SRM 971, BCR 576, 577, and 578) and a high order reference method (mean bias 1.25% for testosterone and −0.84% for estradiol). The high accuracy of the method was monitored and certified by CDC Hormone Standardization (HoSt) Program for two years with mean bias −0.7% (95%CI: −1.6% to 0.2%) for testosterone and 0.1% (95%CI: −2.2% to 2.3%) for estradiol. The method precision over a 2-year period for Quality Control pools at low, medium and high concentrations was 2.7–2.9% for testosterone and 3.3–5.3% for estradiol. With the consistently excellent accuracy and precision, this method is readily applicable for high-throughput clinical and epidemiological studies. PMID:28801832

  16. [Establishment of simultaneous measurement method of 8 salivary components using urinary test paper and clinical evaluation of oral environment].

    Yuuki, Kenji; Tsukasaki, Hiroaki; Kawawa, Tadaharu; Shiba, Akihiko; Shiba, Kiyoko

    2008-07-01

    Clinical findings were compared with glucose, protein, albumin, bilirubin, creatinine, pH, occult blood, ketone body, nitrite, and white blood cells contained in whole saliva to investigate the components that most markedly reflect the periodontal condition. The subjects were staff of the Prosthodontics Department, Showa University, and patients who visited for dental treatments (57 subjects in total). At the first time, saliva samples were gargled with 1.5 ml of distilled water for 15 seconds and collected by spitting out into a paper cup. At the second time, saliva samples were collected by the same method. At the third time, saliva samples after chewing paraffin gum for 60 seconds were collected by spitting out into a paper cup. Thus whole saliva collecting that was divided on three times. After sampling, 8 mul of the saliva sample was dripped in reagent sticks for the 10 items of urinary test paper and the reflectance was measured using a specific reflectometer. In the periodontal tissue evaluation, the degree of alveolar bone resorption, probing value, and tooth mobility and the presence or absence of lesions in the root furcation were examined and classified into 4 ranks. The mean values in each periodontal disease rank and correlation between the periodontal disease ranks and the components were statistically analyzed. Bilirubin and ketone body were not measurable. The components density of the 8 items was increased as the periodontal disease rank increased. Regarding the correlation between the periodontal disease ranks and the components, high correlations were noted for protein, albumin, creatinine, pH, and white blood cells. The simultaneous measurement method of 8 salivary components using test paper may be very useful for the diagnosis of periodontal disease of abutment teeth.

  17. Measures for simultaneous minimisation of alkali related operating problems; Aatgaerder foer samtidig minimering av alkalirelaterade driftproblem. Ramprogram

    Davidsson, Kent; Eskilsson, David; Gyllenhammar, Marianne; Herstad Svaerd, Solvie; Kassman, Haakan; Steenari, Britt-Marie; Aamand, Lars-Erik

    2006-12-15

    Combustion of biofuel and waste wood is often accompanied by chlorine and alkali related operating problems such as slagging, deposit formation and corrosion on heat exchanger surfaces and bed agglomeration in fluidised bed boilers. In order to gain a greater insight into possible measures to overcome alkali related operating problems studies were carried out during 2005-2006. The results of the studies are presented in this report which includes work performed in the two following projects: 1 A5-509 Frame work - measures for simultaneous minimisation of alkali related operating problems 2 A5-505 Bed agglomeration risk related to combustion of cultivated fuels (wheat straw, red canary grass, industrial hemp) in commercial bed materials Full-scale experiments were carried out at Chalmers 12 MW{sub th} CFB boiler within the project A5-509. The purpose was to study the effect of various measures on bed agglomeration and deposit formation in connection with co-combustion of wood and straw pellets. The various measures included changing the bed material (blast furnace sand and olivine sand), adding various additives (kaolin, ammonium sulphate, elemental sulphur) and also co-combustion with sewage sludge. Furthermore results from kaolin experiments at the 26 MWth CFB boiler owned by Naessjoe Affaersverk were made available during the project and are also presented in this report. The results from the experiments at Chalmers revealed that, already at the lowest dosage of kaolin, approx. 2 kg/MWh, the bed material agglomeration temperatures increased significantly. The dosage of kaolin can presumably be reduced somewhat further while still maintaining the high agglomeration temperature. Experiments with a higher dosage of kaolin, 7 kg/MWh, proved that kaolin could also reduce the risk of deposit problems. The experiments at Naessjoe showed also that addition of kaolin increased the agglomeration temperature of the bed material. Addition of sulphur in any form resulted in a

  18. On the use of simultaneous measurements of OH and O2 emissions to investigate wave growth and dissipation

    A. Taori

    2007-03-01

    Full Text Available Simultaneous measurements of mesospheric OH (6–2 Meinel and O2 (0–1 Atmospheric band emissions from a low-latitude station, Maui, Hawaii (20.8° N, 156.2° W are utilized to study the wave characteristics and associated processes. Deduced temperatures show large variability in both OH and O2 data. The seasonal variability in the temperature shows a well-defined, semiannual type of oscillation, which are comparable to the ground-based rocket sounding data. The "Wave Growth Factor", a ratio of normalized perturbation amplitude in O2 to the OH temperature variability, is estimated for principal as well as residual smaller period components of the nocturnal variability. It is noticed that smaller period waves (less than 12 h occasionally have large growth factors of about 3–4 during equinox transitions, an indication of wave amplitude amplification within the 87–94 km altitudes while a strong wave-dissipation occurs throughout the year.

  19. Simultaneous measurement of free-living energy expenditure by the doubly labeled water method and heart-rate monitoring

    Livingstone, M.B.; Prentice, A.M.; Coward, W.A.; Ceesay, S.M.; Strain, J.J.; McKenna, P.G.; Nevin, G.B.; Barker, M.E.; Hickey, R.J.

    1990-01-01

    Total energy expenditure (TEE) was measured simultaneously in 14 free-living adults over 15 d by the doubly labeled water (DLW) method and for 2-4 separate days by heart-rate (HR) monitoring. Individual curves for HR vs oxygen consumption (VO2) were obtained and an HR (FLEX HR: 97 +/- 8 beats/min, range 84-113 beats/min) that discriminated between rest and activity was identified. Calibration curves were used to assign an energy value to daytime HR above FLEX HR. Below FLEX HR energy expenditure was taken as resting metabolism. Sleeping energy expenditure was assumed to be equal to basal metabolic rate. Average HR TEE (12.99 +/- 3.83 MJ/d) and average DLW TEE (12.89 +/- 3.80 MJ/d) were similar. HR TEE discrepancies ranged from -22.2% to +52.1%, with nine values lying within +/- 10% of DLW TEE estimates. The FLEX HR method provides a close estimation of the TEE of population groups. However, an increased number of sampling days may improve the precision of individual estimates of TEE

  20. Simultaneous measurements of auto-immune and infectious disease specific antibodies using a high throughput multiplexing tool.

    Atul Asati

    Full Text Available Considering importance of ganglioside antibodies as biomarkers in various immune-mediated neuropathies and neurological disorders, we developed a high throughput multiplexing tool for the assessment of gangliosides-specific antibodies based on Biolpex/Luminex platform. In this report, we demonstrate that the ganglioside high throughput multiplexing tool is robust, highly specific and demonstrating ∼100-fold higher concentration sensitivity for IgG detection than ELISA. In addition to the ganglioside-coated array, the high throughput multiplexing tool contains beads coated with influenza hemagglutinins derived from H1N1 A/Brisbane/59/07 and H1N1 A/California/07/09 strains. Influenza beads provided an added advantage of simultaneous detection of ganglioside- and influenza-specific antibodies, a capacity important for the assay of both infectious antigen-specific and autoimmune antibodies following vaccination or disease. Taken together, these results support the potential adoption of the ganglioside high throughput multiplexing tool for measuring ganglioside antibodies in various neuropathic and neurological disorders.

  1. Simultaneous measurements of new particle formation at 1 s time resolution at a street site and a rooftop site

    Zhu, Yujiao; Yan, Caiqing; Zhang, Renyi; Wang, Zifa; Zheng, Mei; Gao, Huiwang; Gao, Yang; Yao, Xiaohong

    2017-08-01

    This study is the first to use two identical Fast Mobility Particle Sizers for simultaneous measurement of particle number size distributions (PNSDs) at a street site and a rooftop site within 500 m distance in wintertime and springtime to investigate new particle formation (NPF) in Beijing. The collected datasets at 1 s time resolution allow deduction of the freshly emitted traffic particle signal from the measurements at the street site and thereby enable the evaluation of the effects on NPF in an urban atmosphere through a site-by-site comparison. The number concentrations of 8 to 20 nm newly formed particles and the apparent formation rate (FR) in the springtime were smaller at the street site than at the rooftop site. In contrast, NPF was enhanced in the wintertime at the street site with FR increased by a factor of 3 to 5, characterized by a shorter NPF time and higher new particle yields than at the rooftop site. Our results imply that the street canyon likely exerts distinct effects on NPF under warm or cold ambient temperature conditions because of on-road vehicle emissions, i.e., stronger condensation sinks that may be responsible for the reduced NPF in the springtime but efficient nucleation and partitioning of gaseous species that contribute to the enhanced NPF in the wintertime. The occurrence or absence of apparent growth for new particles with mobility diameters larger than 10 nm was also analyzed. The oxidization of biogenic organics in the presence of strong photochemical reactions is suggested to play an important role in growing new particles with diameters larger than 10 nm, but sulfuric acid is unlikely to be the main species for the apparent growth. However, the number of datasets used in this study is relatively small, and larger datasets are essential to draw a general conclusion.

  2. Estimates of Active Region Area Coverage through Simultaneous Measurements of the He i λλ 5876 and 10830 Lines

    Andretta, Vincenzo; Covino, Elvira [INAF—Osservatorio Astronomico di Capodimonte Salita Moiariello, 16 I-80131 Naples (Italy); Giampapa, Mark S. [National Solar Observatory 950 N. Cherry Avenue Tucson, AZ 85719 (United States); Reiners, Ansgar [Institut für Astrophysik Georg-August-Universität Göttingen Friedrich-Hund-Platz 1 D-37077 Göttingen (Germany); Beeck, Benjamin, E-mail: andretta@oacn.inaf.it [Max Planck Institute for Solar System Research Justus-von-Liebig-Weg 3 D-37077 Göttingen (Germany)

    2017-04-20

    Simultaneous, high-quality measurements of the neutral helium triplet features at 5876 Å and 10830 Å in a sample of solar-type stars are presented. The observations were made with ESO telescopes at the La Silla Paranal Observatory under program ID 088.D-0028(A) and MPG Utility Run for Fiber Extended-range Optical Spectrograph 088.A-9029(A). The equivalent widths of these features combined with chromospheric models are utilized to infer the fractional area coverage, or filling factor, of magnetic regions outside of spots. We find that the majority of the sample is characterized by filling factors less than unity. However, discrepancies occur among the coolest K-type and the warmest and most rapidly rotating F-type dwarf stars. We discuss these apparently anomalous results and find that in the case of K-type stars, they are an artifact of the application of chromospheric models best suited to the Sun than to stars with significantly lower T {sub eff}. The case of the F-type rapid rotators can be explained by the measurement uncertainties of the equivalent widths, but they may also be due to a non-magnetic heating component in their atmospheres. With the exceptions noted above, preliminary results suggest that the average heating rates in the active regions are the same from one star to the other, differing in the spatially integrated, observed level of activity due to the area coverage. Hence, differences in activity in this sample are mainly due to the filling factor of active regions.

  3. Optimal Weighting of Multi-Spacecraft Data to Estimate Gradients of Physical Fields

    Chanteur, G. M.; Le Contel, O.; Sahraoui, F.; Retino, A.; Mirioni, L.

    2016-12-01

    Multi-spacecraft missions like the ESA mission CLUSTER and the NASA mission MMS are essential to improve our understanding of physical processes in space plasmas. Several methods were designed in the 90's during the preparation phase of the CLUSTER mission to estimate gradients of physical fields from simultaneous multi-points measurements [1, 2]. Both CLUSTER and MMS involve four spacecraft with identical full scientific payloads including various sensors of electromagnetic fields and different type of particle detectors. In the standard methods described in [1, 2], which are presently in use, data from the four spacecraft have identical weights and the estimated gradients are most reliable when the tetrahedron formed by the four spacecraft is regular. There are three types of errors affecting the estimated gradients (see chapter 14 in [1]) : i) truncature errors are due to local non-linearity of spatial variations, ii) physical errors are due to instruments, and iii) geometrical errors are due to uncertainties on the positions of the spacecraft. An assessment of truncature errors for a given observation requires a theoretical model of the measured field. Instrumental errors can easily be taken into account for a given geometry of the cluster but are usually less than the geometrical errors which diverge quite fast when the tetrahedron flattens, a circumstance occurring twice per orbit of the cluster. Hence reliable gradients can be estimated only on part of the orbit. Reciprocal vectors of the tetrahedron were presented in chapter 4 of [1], they have the advantage over other methods to treat the four spacecraft symmetrically and to allow a theoretical analysis of the errors (see chapters 4 of [1] and 4 of [2]). We will present Generalized Reciprocal Vectors for weighted data and an optimization procedure to improve the reliability of the estimated gradients when the tetrahedron is not regular. A brief example using CLUSTER or MMS data will be given. This approach

  4. A small sized time-of-flight mass spectrometer for simultaneous measurement of neutral and ionic species effusing from plasma, 1

    Horiuchi, Yukihiko

    1986-01-01

    A principle for simultaneous and real time measurement of neutral and ionic species effusing from plasma by using a time-of-flight mass spectrometer is proposed. A simple, small sized time-of-flight mass spectrometer combined with a dc glow discharge tube and an ion sampling electrode system for the simultaneous measurement on the basis of the proposed plinciple, has been constructed and tested. Details of the experimental setup including the geometry and the electronic hardware are described. It is shown that mass spectra of neutrals and ions from the positive column of the argon dc glow discharge are successfully observed on a single oscilloscope display. (author)

  5. Spacecraft Angular Rates Estimation with Gyrowheel Based on Extended High Gain Observer

    Xiaokun Liu

    2016-04-01

    Full Text Available A gyrowheel (GW is a kind of electronic electric-mechanical servo system, which can be applied to a spacecraft attitude control system (ACS as both an actuator and a sensor simultaneously. In order to solve the problem of two-dimensional spacecraft angular rate sensing as a GW outputting three-dimensional control torque, this paper proposed a method of an extended high gain observer (EHGO with the derived GW mathematical model to implement the spacecraft angular rate estimation when the GW rotor is working at large angles. For this purpose, the GW dynamic equation is firstly derived with the second kind Lagrange method, and the relationship between the measurable and unmeasurable variables is built. Then, the EHGO is designed to estimate and calculate spacecraft angular rates with the GW, and the stability of the designed EHGO is proven by the Lyapunov function. Moreover, considering the engineering application, the effect of measurement noise in the tilt angle sensors on the estimation accuracy of the EHGO is analyzed. Finally, the numerical simulation is performed to illustrate the validity of the method proposed in this paper.

  6. A dark matter detector based on the simultaneous measurement of phonons and ionization at 20 mK

    Shutt, Thomas Alan [UC, Berkeley

    1993-01-01

    One of the most important issues in astrophysics and cosmology is understanding the nature of dark matter. One possibility is that it is made of weakly interacting subatomic particles created in the big bang, such as the lightest particle in supersymmetry models. These particles should scatter elastically of nuclei in a detector on earth at a rate of ~events/kg/week, and will deposit energies of a few keV. Current attempts to detect these interactions are limited by a radioactive background of photons and beta particles which scatter on electrons. We have developed a novel particle detector to look for dark matter based on the simultaneous measurement of ionization and phonons in a 60 g crystal of high purity germanium at a temperature of 20 mK. Background events can be distinguished by our detector because they produce more ionization per unit phonon energy than dark matter interactions. The phonon energy is measured as a temperature change in the detector by means of neutron transmutation doped germanium thermistors attached to the crystal. The ionization measurement is accomplished by applying a bias to implanted contacts on the faces of the disk. Charge collection differs from the normal situation at 77 K in that no thermally generated free charge exists in the crystal at 20 mK. The collection efficiency is good with an electric field of only ~0.2 V/cm after the charged impurities in the crystal have been neutralized by free charge created by particle interactions from a radioactive source. For fields below this charge collection is poor, and affects the amount of phonon energy measured. We have modeled this in terms of charge trapping. The r.m.s resolution of the detector is 800 eV in phonons and 600 eV in ionization. We have tested the background rejection capability of the detector by exposing it to neutrons from a 251Cf source which scatter elastically on nuclei. The neutrons are distinguished at energies of a few keV, and the current background rejection

  7. Lessons from simultaneous measurements of soil respiration and net ecosystem exchange of CO2 in temperate forests

    Renchon, A.; Pendall, E.

    2017-12-01

    Land-surface exchanges of CO2 play a key role in ameliorating or exacerbating climate change. The eddy-covariance method allows direct measurement of net ecosystem-atmosphere exchange of CO2 (NEE), but partitioning daytime NEE into its components - gross primary productivity (GPP) and ecosystem respiration (RE) - remains challenging. Continuous measurements of soil respiration (RS), along with flux towers, have the potential to better constrain data and models of RE and GPP. We use simultaneous half-hourly NEE and RS data to: (1) compare the short-term (fortnightly) apparent temperature sensitivity (Q10) of nighttime RS and RE; (2) assess whether daytime RS can be estimated using nighttime response functions; and (3) compare the long-term (annual) responses of nighttime RS and nighttime RE to interacting soil moisture and soil temperature. We found that nighttime RS has a lower short-term Q10 than nighttime RE. This suggests that the Q10 of nighttime RE is strongly influenced by the Q10 of nighttime above-ground respiration, or possibly by a bias in RE measurements. The short-term Q10 of RS and RE decreased with increasing temperature. In general, daytime RS could be estimated using nighttime RS temperature and soil moisture (r2 = 0.9). However, this results from little to no diurnal variation in RS, and estimating daytime RS as the average of nighttime RS gave similar results (r2 = 0.9). Furthermore, we observed a day-night hysteresis of RS response to temperature, especially when using air temperature and sometimes when using soil temperature at 5cm depth. In fact, during some months, soil respiration observations were lower during daytime compared to nighttime, despite higher temperature in daytime. Therefore, daytime RS modelled from nighttime RS temperature response was overestimated during these periods. RS and RE responses to the combination of soil moisture and soil temperature were similar, and consistent with the DAMM model of soil-C decomposition. These

  8. Simultaneous measurement of unfrozen water content and ice content in frozen soil using gamma ray attenuation and TDR

    Zhou, Xiaohai; Zhou, Jian; Kinzelbach, Wolfgang; Stauffer, Fritz

    2014-12-01

    The freezing temperature of water in soil is not constant but varies over a range determined by soil texture. Consequently, the amounts of unfrozen water and ice change with temperature in frozen soil, which in turn affects hydraulic, thermal, and mechanical properties of frozen soil. In this paper, an Am-241 gamma ray source and time-domain reflectometry (TDR) were combined to measure unfrozen water content and ice content in frozen soil simultaneously. The gamma ray attenuation was used to determine total water content. The TDR was used to determine the dielectric constant of the frozen soil. Based on a four-phase mixing model, the amount of unfrozen water content in the frozen soil could be determined. The ice content was inferred by the difference between total water content and unfrozen water content. The gamma ray attenuation and the TDR were both calibrated by a gravimetric method. Water contents measured by gamma ray attenuation and TDR in an unfrozen silt column under infiltration were compared and showed that the two methods have the same accuracy and response to changes of water content. Unidirectional column freezing experiments were performed to apply the combined method of gamma ray attenuation and TDR for measuring unfrozen water content and ice content. The measurement error of the gamma ray attenuation and TDR was around 0.02 and 0.01 m3/m3, respectively. The overestimation of unfrozen water in frozen soil by TDR alone was quantified and found to depend on the amount of ice content. The higher the ice content, the larger the overestimation. The study confirmed that the combined method could accurately determine unfrozen water content and ice content in frozen soil. The results of soil column freezing experiments indicate that total water content distribution is affected by available pore space and the freezing front advance rate. It was found that there is similarity between the soil water characteristic and the soil freezing characteristic of

  9. Simultaneous GC-ECNICI-MS measurement of nitrite, nitrate and creatinine in human urine and plasma in clinical settings.

    Hanff, Erik; Lützow, Moritz; Kayacelebi, Arslan Arinc; Finkel, Armin; Maassen, Mirja; Yanchev, Georgi Radoslavov; Haghikia, Arash; Bavendiek, Udo; Buck, Anna; Lücke, Thomas; Maassen, Norbert; Tsikas, Dimitrios

    2017-03-15

    Creatinine in urine is a useful biochemical parameter to correct the urinary excretion rate of endogenous and exogenous substances. Nitrite (ONO - ) and nitrate (ONO 2 - ) are metabolites of nitric oxide (NO), a signalling molecule with multiple biological functions. Under certain and standardized conditions, the concentration of nitrate in the urine is a suitable measure of whole body NO synthesis. The urinary nitrate-to-nitrite molar ratio (U NOx R) may indicate nitrite-dependent renal carbonic anhydrase (CA) activity. In clinical studies, urine is commonly collected by spontaneous micturition. In those cases the nitrate and nitrite excretion must be corrected for creatinine excretion. Pentafluorobenzyl (PFB) bromide (PFB-Br) is a useful derivatization reagent of numerous inorganic and organic compounds, including urinary nitrite, nitrate and creatinine, for highly sensitive and specific quantitation by GC-MS. Here, we report on the simultaneous PFB-Br derivatization (60min, 50°C) of ONO - , O 15 NO - , ONO 2 - , O 15 NO 2 - , creatinine (d o -Crea) and [methylo- 2 H 3 ]creatinine (d 3 -Crea) in acetonic dilutions of native human urine and plasma samples (4:1, v/v) and their simultaneous quantification by GC-MS as PFBNO 2 , PFB 15 NO 2 , PFBONO 2 , PFBO 15 NO 2 , d o -Crea-PFB and d 3 -Crea-PFB, respectively. Electron capture negative-ion chemical ionization (ECNICI) of these derivatives generates anions due to [M-PFB] - , i.e., the starting analytes. Quantification is performed by selected-ion monitoring (SIM) of m/z 46 (ONO - ), m/z 47 (O 15 NO - ), m/z 62 (ONO 2 - ), m/z 63 (O 15 NO 2 - ), m/z 112 (d o -Crea), and m/z 115 (d 3 -Crea). Retention times were 2.97min for PFB-ONO 2 /PFB-O 15 NO 2 , 3.1min for PFB-NO 2 /PFB- 15 NO 2 , and 6.7min for d o -Crea-PFB/d 3 -Crea-PFB. We used this method to investigate the effects of long-term oral NaNO 3 or NaCl (serving as placebo) supplementation (each 0.1mmol/kg body weight per day for 3 weeks) on creatinine excretion

  10. Intelligent spacecraft module

    Oungrinis, Konstantinos-Alketas; Liapi, Marianthi; Kelesidi, Anna; Gargalis, Leonidas; Telo, Marinela; Ntzoufras, Sotiris; Paschidi, Mariana

    2014-12-01

    The paper presents the development of an on-going research project that focuses on a human-centered design approach to habitable spacecraft modules. It focuses on the technical requirements and proposes approaches on how to achieve a spatial arrangement of the interior that addresses sufficiently the functional, physiological and psychosocial needs of the people living and working in such confined spaces that entail long-term environmental threats to human health and performance. Since the research perspective examines the issue from a qualitative point of view, it is based on establishing specific relationships between the built environment and its users, targeting people's bodily and psychological comfort as a measure toward a successful mission. This research has two basic branches, one examining the context of the system's operation and behavior and the other in the direction of identifying, experimenting and formulating the environment that successfully performs according to the desired context. The latter aspect is researched upon the construction of a scaled-model on which we run series of tests to identify the materiality, the geometry and the electronic infrastructure required. Guided by the principles of sensponsive architecture, the ISM research project explores the application of the necessary spatial arrangement and behavior for a user-centered, functional interior where the appropriate intelligent systems are based upon the existing mechanical and chemical support ones featured on space today, and especially on the ISS. The problem is set according to the characteristics presented at the Mars500 project, regarding the living quarters of six crew-members, along with their hygiene, leisure and eating areas. Transformable design techniques introduce spatial economy, adjustable zoning and increased efficiency within the interior, securing at the same time precise spatial orientation and character at any given time. The sensponsive configuration is

  11. The interaction of a flowing plasma with a dipole magnetic field: measurements and modelling of a diamagnetic cavity relevant to spacecraft protection

    Bamford, R; Bradford, J; Bingham, R; Gargate, L; Hapgood, M; Stamper, R; Gibson, K J; Thornton, A J; Silva, L O; Fonseca, R A; Norberg, C; Todd, T

    2008-01-01

    Here we describe a new experiment to test the shielding concept of a dipole-like magnetic field and plasma, surrounding a spacecraft forming a 'mini magnetosphere'. Initial laboratory experiments have been conducted to determine the effectiveness of a magnetized plasma barrier to be able to expel an impacting, low beta, supersonic flowing energetic plasma representing the solar wind. Optical and Langmuir probe data of the plasma density, the plasma flow velocity and the intensity of the dipole field clearly show the creation of a narrow transport barrier region and diamagnetic cavity virtually devoid of energetic plasma particles. This demonstrates the potential viability of being able to create a small 'hole' in a solar wind plasma, of the order of the ion Larmor orbit width, in which an inhabited spacecraft could reside in relative safety. The experimental results have been quantitatively compared with a 3D particle-in-cell 'hybrid' code simulation that uses kinetic ions and fluid electrons, showing good qualitative agreement and excellent quantitative agreement. Together the results demonstrate the pivotal role of particle kinetics in determining generic plasma transport barriers.

  12. Simultaneously combining AOD and multiple trace gas measurements to identify decadal changes in urban and biomass burning aerosols

    Cohen, Jason

    2017-04-01

    This work presents a methodology by which to comprehensively analyze simultaneous tropospheric measurements of AOD and associated trace gasses. It then applies this methodology by focusing over the past 11 years (2006-2016) on one of the most rapidly changing regions of the troposphere: Eastern and Southeastern Asia. The specific work presented incorporates measurements of both aerosol and related gas phase tropospheric measurements across different spectral, spatial, temporal, and passive/active sensors and properties, including: MODIS, MISR, OMI, CALIOP, and others. This new characterization reveals a trio of new information, including a time-invariant urban signal, slowly-time-varying new-urbanization signal, and a rapidly time-varying biomass burning signal. Additionally, due to the different chemical properties of the various species analyzed, analyzing the different spatial domains of the resulting products allows for further information in terms of the amounts of aerosols produced both through primary emissions as well as secondary processing. The end result is a new characterization, in space, time, and magnitude, of both anthropogenic and biomass burning aerosols. These results are then used to drive an advanced modeling system including aerosol chemistry, physics, optics, and transport, and employing an aerosol routine based on multi-modal and both externally mixed and core-shell mixing. The resulting characterization in space, time, and quantity is analyzed and compared against AERONET, NOAA, and other ground networks, with the results comparing consistently to or better than present approaches which set up net emissions separately from urban and biomass burning products. Scientifically, new source regions of emissions are identified, some of which were previously non-urbanized or found to not contain any fire hotspots. This new approach is consistent with the underlying economic and development pathways of expanding urban areas and rapid economic growth

  13. First results of a simultaneous measurement of tritium and 14C in an ultra-low-background proportional counter for environmental sources of methane

    Mace, Emily K.; Aalseth, Craig E.; Day, Anthony R.; Hoppe, Eric W.; Keillor, Martin E.; Moran, James J.; Panisko, Mark E.; Seifert, Allen; Tatishvili, Gocha; Williams, Richard M.

    2016-02-01

    Abstract Simultaneous measurement of tritium and 14C would provide an added tool for tracing organic compounds through environmental systems and is possible via beta energy spectroscopy of sample-derived methane in internal-source gas proportional counters. Since the mid-1960’s atmospheric tritium and 14C have fallen dramatically as the isotopic injections from above-ground nuclear testing have been diluted into the ocean and biosphere. In this work, the feasibility of simultaneous tritium and 14C measurements via proportional counters is revisited in light of significant changes in both the atmospheric and biosphere isotopics and the development of new ultra-low-background gas proportional counting capabilities for small samples (roughly 50 cc methane). A Geant4 Monte Carlo model of a Pacific Northwest National Laboratory (PNNL) proportional counter response to tritium and 14C is used to analyze small samples of two different methane sources to illustrate the range of applicability of contemporary simultaneous measurements and their limitations. Because the two methane sources examined were not sample size limited, we could compare the small-sample measurements performed at PNNL with analysis of larger samples performed at a commercial laboratory. The dual-isotope simultaneous measurement is well matched for methane samples that are atmospheric or have an elevated source of tritium (i.e. landfill gas). For samples with low/modern tritium isotopics (rainwater), commercial separation and counting is a better fit.

  14. Simultaneous measurement of current and temperature distributions in a proton exchange membrane fuel cell during cold start processes

    Jiao Kui; Alaefour, Ibrahim E.; Karimi, Gholamreza; Li Xianguo

    2011-01-01

    Cold start is critical to the commercialization of proton exchange membrane fuel cell (PEMFC) in automotive applications. Dynamic distributions of current and temperature in PEMFC during various cold start processes determine the cold start characteristics, and are required for the optimization of design and operational strategy. This study focuses on an investigation of the cold start characteristics of a PEMFC through the simultaneous measurements of current and temperature distributions. An analytical model for quick estimate of purging duration is also developed. During the failed cold start process, the highest current density is initially near the inlet region of the flow channels, then it moves downstream, reaching the outlet region eventually. Almost half of the cell current is produced in the inlet region before the cell current peaks, and the region around the middle of the cell has the best survivability. These two regions are therefore more important than other regions for successful cold start through design and operational strategy, such as reducing the ice formation and enhancing the heat generation in these two regions. The evolution of the overall current density distribution over time remains similar during the successful cold start process; the current density is the highest near the flow channel inlets and generally decreases along the flow direction. For both the failed and the successful cold start processes, the highest temperature is initially in the flow channel inlet region, and is then around the middle of the cell after the overall peak current density is reached. The ice melting and liquid formation during the successful cold start process have negligible influence on the general current and temperature distributions.

  15. Spacecraft Thermal Management

    Hurlbert, Kathryn Miller

    2009-01-01

    In the 21st century, the National Aeronautics and Space Administration (NASA), the Russian Federal Space Agency, the National Space Agency of Ukraine, the China National Space Administration, and many other organizations representing spacefaring nations shall continue or newly implement robust space programs. Additionally, business corporations are pursuing commercialization of space for enabling space tourism and capital business ventures. Future space missions are likely to include orbiting satellites, orbiting platforms, space stations, interplanetary vehicles, planetary surface missions, and planetary research probes. Many of these missions will include humans to conduct research for scientific and terrestrial benefits and for space tourism, and this century will therefore establish a permanent human presence beyond Earth s confines. Other missions will not include humans, but will be autonomous (e.g., satellites, robotic exploration), and will also serve to support the goals of exploring space and providing benefits to Earth s populace. This section focuses on thermal management systems for human space exploration, although the guiding principles can be applied to unmanned space vehicles as well. All spacecraft require a thermal management system to maintain a tolerable thermal environment for the spacecraft crew and/or equipment. The requirements for human rating and the specified controlled temperature range (approximately 275 K - 310 K) for crewed spacecraft are unique, and key design criteria stem from overall vehicle and operational/programatic considerations. These criteria include high reliability, low mass, minimal power requirements, low development and operational costs, and high confidence for mission success and safety. This section describes the four major subsystems for crewed spacecraft thermal management systems, and design considerations for each. Additionally, some examples of specialized or advanced thermal system technologies are presented

  16. Simultaneous measurement of thermal conductivity and heat capacity of bulk and thin film materials using frequency-dependent transient thermoreflectance method.

    Liu, Jun; Zhu, Jie; Tian, Miao; Gu, Xiaokun; Schmidt, Aaron; Yang, Ronggui

    2013-03-01

    The increasing interest in the extraordinary thermal properties of nanostructures has led to the development of various measurement techniques. Transient thermoreflectance method has emerged as a reliable measurement technique for thermal conductivity of thin films. In this method, the determination of thermal conductivity usually relies much on the accuracy of heat capacity input. For new nanoscale materials with unknown or less-understood thermal properties, it is either questionable to assume bulk heat capacity for nanostructures or difficult to obtain the bulk form of those materials for a conventional heat capacity measurement. In this paper, we describe a technique for simultaneous measurement of thermal conductivity κ and volumetric heat capacity C of both bulk and thin film materials using frequency-dependent time-domain thermoreflectance (TDTR) signals. The heat transfer model is analyzed first to find how different combinations of κ and C determine the frequency-dependent TDTR signals. Simultaneous measurement of thermal conductivity and volumetric heat capacity is then demonstrated with bulk Si and thin film SiO2 samples using frequency-dependent TDTR measurement. This method is further testified by measuring both thermal conductivity and volumetric heat capacity of novel hybrid organic-inorganic thin films fabricated using the atomic∕molecular layer deposition. Simultaneous measurement of thermal conductivity and heat capacity can significantly shorten the development∕discovery cycle of novel materials.

  17. Simultaneous measurement of trace metal and oxyanion concentrations in water using diffusive gradients in thin films with a chelex-metsorb mixed binding layer

    Panther, Jared G.; Bennett, William W.; Welsh, David T.

    2014-01-01

    A new diffusive gradients in thin films (DGT) technique with a mixed binding layer (Chelex-100 and the titanium dioxide based adsorbent Metsorb) is described for the simultaneous measurement of labile trace metal (Mn, Co, Ni, Cu, Cd, and Pb) and oxyanion (V, As, Mo, Sb, W, and P) concentrations i...

  18. Simultaneous perineal ultrasound and vaginal pressure measurement prove the action of electrical pudendal nerve stimulation in treating female stress incontinence.

    Wang, Siyou; Zhang, Shujing

    2012-11-01

    Study Type - Diagnostic (case series) Level of Evidence 4. What's known on the subject? and What does the study add? Pelvic floor muscle training (PFMT) and transvaginal electrical stimulation (TES) are two commonly used forms of conservative treatment for stress urinary incontinence (SUI). PFMT may build up the structural support of the pelvis, but many SUI patients are unable to perform PFMT effectively and its primary disadvantage is lack of long-term patient compliance. TES is a passive treatment that produces PFM contraction and patient compliance with it is good; however, its effect is not as good as that of PFMT when performed correctly. Electrical pudendal nerve stimulation (EPNS) combines the advantages of PFMT and TES and incorporates the technique of deep insertion of long needles. In this study, simultaneous perineal ultrasound and vaginal pressure measurement prove that EPNS can contract the PFM and simulate PFMT. It is shown that EPNS is an alternative therapy for female SUI patients who fail PFMT and TES and the therapy can also be used for severe SUI. • To prove that electrical pudendal nerve stimulation (EPNS) can contract the pelvic floor muscles (PFM) and simulate pelvic floor muscle training (PFMT). • To show that EPNS is an alternative therapy for female stress urinary incontinence (SUI) that does not respond effectively to PFMT and transvaginal electrical stimulation (TES). • Thirty-five female patients with SUI who did not respond effectively to PFMT and TES (group I) were enrolled and 60 other female patients with SUI were allocated to group II (30 patients) and group III (30 patients). • Long needles were deeply inserted into four sacral points and electrified to stimulate the pudendal nerves. Group I and group II were treated by a doctor skilled in performing EPNS and group III, by a doctor unskilled in performing EPNS. • When EPNS was performed in group I, perineal ultrasonographic PFM movements, vaginal pressure (VP) and PFM

  19. Research on the improvement of nuclear safety - Development of a technique for simultaneous measurement of particle size and velocity for direct containment heating accident analysis

    Lee, Sang Yong; Song, Si Hong; Koh, Kwang Woong; Kim, Joo Yeon; Kim, Jong Moon; Choi, Chul Jin [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1995-08-01

    The main objective is to develop a high performance software routine to process the output signals from the phase/Doppler device for simultaneous measurement of drop sizes and two-dimensional velocities of spray drops/particles. The present work has been carried out as an extension work of the first year`s research, where the principles and the limitation of this measuring technique have been thoroughly reviewed. In order to verify the performance and reliability of this software for simultaneous measurement of sizes and velocities of spray drops with two-dimensional motions, the results were compared with those from commercial signal processor DSA by Aerometrics, and concluded to be satisfactory. The routine developed throughout this project is applicable not only to the DCH model experiments but also to the measurements of sizes and velocities of drops/particles in combustors, dryers, humidifiers, and in various two-phase equipments. 20 refs., 5 tabs., 21 figs. (author)

  20. Large-Scale Spacecraft Fire Safety Tests

    Urban, David; Ruff, Gary A.; Ferkul, Paul V.; Olson, Sandra; Fernandez-Pello, A. Carlos; T'ien, James S.; Torero, Jose L.; Cowlard, Adam J.; Rouvreau, Sebastien; Minster, Olivier; hide

    2014-01-01

    An international collaborative program is underway to address open issues in spacecraft fire safety. Because of limited access to long-term low-gravity conditions and the small volume generally allotted for these experiments, there have been relatively few experiments that directly study spacecraft fire safety under low-gravity conditions. Furthermore, none of these experiments have studied sample sizes and environment conditions typical of those expected in a spacecraft fire. The major constraint has been the size of the sample, with prior experiments limited to samples of the order of 10 cm in length and width or smaller. This lack of experimental data forces spacecraft designers to base their designs and safety precautions on 1-g understanding of flame spread, fire detection, and suppression. However, low-gravity combustion research has demonstrated substantial differences in flame behavior in low-gravity. This, combined with the differences caused by the confined spacecraft environment, necessitates practical scale spacecraft fire safety research to mitigate risks for future space missions. To address this issue, a large-scale spacecraft fire experiment is under development by NASA and an international team of investigators. This poster presents the objectives, status, and concept of this collaborative international project (Saffire). The project plan is to conduct fire safety experiments on three sequential flights of an unmanned ISS re-supply spacecraft (the Orbital Cygnus vehicle) after they have completed their delivery of cargo to the ISS and have begun their return journeys to earth. On two flights (Saffire-1 and Saffire-3), the experiment will consist of a flame spread test involving a meter-scale sample ignited in the pressurized volume of the spacecraft and allowed to burn to completion while measurements are made. On one of the flights (Saffire-2), 9 smaller (5 x 30 cm) samples will be tested to evaluate NASAs material flammability screening tests

  1. A New Method for Simultaneous Measurement of the Integrated Reflectivity of Crystals at Multiple Orders of Reflection and Comparison with New Theoretical Calculations

    Lee, S.G.; Bak, J.G.; Jung, Y.S.; Bitter, M.; Hill, K.W.; Hoelzer, G.; Wehrhan, O.; Foerster, E.

    2003-01-01

    This paper describes a new method for the simultaneous measurement of the integrated reflectivity of a crystal for multiple orders of reflection at a predefined Bragg angle. The technique is demonstrated with a mica crystal for Bragg angles of 43 o , 47 o , and 50 o . The measured integrated reflectivity for Bragg reflections up to the 24th order is compared with new theoretical predictions, which are also presented in this paper

  2. Detecting concealed information from groups using a dynamic questioning approach: simultaneous skin conductance measurement and immediate feedback

    Ewout H Meijer

    2013-02-01

    Full Text Available Lie detection procedures typically aim at determining the guilt or innocence of a single suspect. The Concealed Information Test (CIT, for example, has been shown to be highly successful in detecting the presence or absence of crime-related information in a suspect’s memory. Many of today’s security threats, however, do not come from individuals, but from organized groups such as criminal organizations or terrorist networks. In this study, we tested whether a plan of an upcoming mock terrorist attack could be extracted from a group of suspects using a dynamic questioning approach. One-hundred participants were tested in 20 groups of 5. Each group was asked to plan a mock terrorist attack based on a list of potential countries, cities and streets. Next, three questions referring to the country, city, and street were presented, each with 5 options. Skin conductance in all 5 members of the group was measured simultaneously during this presentation. The dynamic questioning approach entailed direct analysis of the data, and if the average skin conductance of the group to a certain option exceeded a threshold, this option was followed up. E.g., if the reaction to the option ‘Italy’ exceeded the threshold, this was followed up by presenting 5 cities in Italy. Results showed that in 19 of the 20 groups the country was correctly detected using this procedure. In 13 of these remaining 19 groups the city was correctly detected. In 7 of these 13, the street was also correctly detected. The question about the country resulted in no false positives (out of 20, the question about the city resulted in 2 false positives (out of 19, while the question about the streets resulted in 2 false positives (out of 13. Furthermore, the 2 false positives at the city level also yielded a false positive at the street level. Taken together these results indicate our dynamic questioning approach can help to unveil plans about a mock terrorist attack.

  3. Simultaneous coastal measurements of ozone deposition fluxes and iodine-mediated particle emission fluxes with subsequent CCN formation

    J. D. Whitehead

    2010-01-01

    Full Text Available Here we present the first observations of simultaneous ozone deposition fluxes and ultrafine particle emission fluxes over an extensive infra-littoral zone. Fluxes were measured by the eddy covariance technique at the Station Biologique de Roscoff, on the coast of Brittany, north-west France. This site overlooks a very wide (3 km littoral zone controlled by very deep tides (9.6 m exposing extensive macroalgae beds available for significant iodine mediated photochemical production of ultrafine particles. The aspect at the Station Biologique de Roscoff provides an extensive and relatively flat, uniform fetch within which micrometeorological techniques may be utilized to study links between ozone deposition to macroalgae (and sea water and ultrafine particle production.

    Ozone deposition to seawater at high tide was significantly slower (vd[O3]=0.302±0.095 mm s−1 than low tidal deposition. A statistically significant difference in the deposition velocities to macroalgae at low tide was observed between night time (vd[O3]=1.00±0.10 mm s−1 and daytime (vd[O3]=2.05±0.16 mm s−1 when ultrafine particle formation results in apparent particle emission. Very high emission fluxes of ultrafine particles were observed during daytime periods at low tides ranging from 50 000 particles cm−2 s−1 to greater than 200 000 particles cm−2 s−1 during some of the lowest tides. These emission fluxes exhibited a significant relationship with particle number concentrations comparable with previous observations at another location. Apparent particle growth rates were estimated to be in the range 17–150 nm h−1 for particles in the size range 3–10 nm. Under certain conditions, particle growth may be inferred to continue to greater than 120 nm over tens

  4. Guidance and control of swarms of spacecraft

    Morgan, Daniel James

    control uses a finite horizon to apply the most up-to-date control sequence while simultaneously calculating a new assignment and trajectory based on updated state information. Using a finite horizon allows collisions to only be considered between spacecraft that are near each other at the current time. This relaxes the all-to-all communication assumption so that only neighboring agents need to communicate. Experimental validation is done using the formation flying testbed. The swarm-reconfiguration algorithms are tested using multiple quadrotors. Experiments have been performed using sequential convex programming for offline trajectory planning, model predictive control and sequential convex programming for real-time trajectory generation, and the variable-swarm, distributed auction algorithm for optimal assignment. These experiments show that the swarm-reconfiguration algorithms can be implemented in real time using actual hardware. In general, this dissertation presents guidance and control algorithms that maintain and reconfigure swarms of spacecraft while maintaining the shape of the swarm, preventing collisions between the spacecraft, and minimizing the amount of propellant used.

  5. Spacecraft exploration of asteroids

    Veverka, J.; Langevin, Y.; Farquhar, R.; Fulchignoni, M.

    1989-01-01

    After two decades of spacecraft exploration, we still await the first direct investigation of an asteroid. This paper describes how a growing international interest in the solar system's more primitive bodies should remedy this. Plans are under way in Europe for a dedicated asteroid mission (Vesta) which will include multiple flybys with in situ penetrator studies. Possible targets include 4 Vesta, 8 Flora and 46 Hestia; launch its scheduled for 1994 or 1996. In the United States, NASA plans include flybys of asteroids en route to outer solar system targets

  6. Spacecraft rendezvous and docking

    Jørgensen, John Leif

    1999-01-01

    The phenomenons and problems encountered when a rendezvous manoeuvre, and possible docking, of two spacecrafts has to be performed, have been the topic for numerous studies, and, details of a variety of scenarios has been analysed. So far, all solutions that has been brought into realization has...... been based entirely on direct human supervision and control. This paper describes a vision-based system and methodology, that autonomously generates accurate guidance information that may assist a human operator in performing the tasks associated with both the rendezvous and docking navigation...

  7. Toward autonomous spacecraft

    Fogel, L. J.; Calabrese, P. G.; Walsh, M. J.; Owens, A. J.

    1982-01-01

    Ways in which autonomous behavior of spacecraft can be extended to treat situations wherein a closed loop control by a human may not be appropriate or even possible are explored. Predictive models that minimize mean least squared error and arbitrary cost functions are discussed. A methodology for extracting cyclic components for an arbitrary environment with respect to usual and arbitrary criteria is developed. An approach to prediction and control based on evolutionary programming is outlined. A computer program capable of predicting time series is presented. A design of a control system for a robotic dense with partially unknown physical properties is presented.

  8. Test-retest measurements of dopamine D{sub 1}-type receptors using simultaneous PET/MRI imaging

    Kaller, Simon; Patt, Marianne; Becker, Georg-Alexander; Luthardt, Julia; Meyer, Philipp M.; Werner, Peter; Barthel, Henryk; Bresch, Anke; Sabri, Osama [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Rullmann, Michael [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig (Germany); Girbardt, Johanna [Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig (Germany); Fritz, Thomas H. [Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig (Germany); University of Gent, Institute for Psychoacoustics and Electronic Music (IPEM), Ghent (Belgium); Hesse, Swen [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Leipzig University Medical Centre, Integrated Research and Treatment Centre (IFB) Adiposity Diseases, Leipzig (Germany)

    2017-06-15

    The role of dopamine D{sub 1}-type receptor (D{sub 1}R)-expressing neurons in the regulation of motivated behavior and reward prediction has not yet been fully established. As a prerequisite for future research assessing D{sub 1}-mediated neuronal network regulation using simultaneous PET/MRI and D{sub 1}R-selective [{sup 11}C]SCH23390, this study investigated the stability of central D{sub 1}R measurements between two independent PET/MRI sessions under baseline conditions. Thirteen healthy volunteers (7 female, age 33 ± 13 yrs) underwent 90-min emission scans, each after 90-s bolus injection of 486 ± 16 MBq [{sup 11}C]SCH23390, on two separate days within 2-4 weeks using a PET/MRI system. Parametric images of D{sub 1}R distribution volume ratio (DVR) and binding potential (BP{sub ND}) were generated by a multi-linear reference tissue model with two parameters and the cerebellar cortex as receptor-free reference region. Volume-of-interest (VOI) analysis was performed with manual VOIs drawn on consecutive transverse MRI slices for brain regions with high and low D{sub 1}R density. The DVR varied from 2.5 ± 0.3 to 2.9 ± 0.5 in regions with high D{sub 1}R density (e.g. the head of the caudate) and from 1.2 ± 0.1 to 1.6 ± 0.2 in regions with low D{sub 1}R density (e.g. the prefrontal cortex). The absolute variability of the DVR ranged from 2.4% ± 1.3% to 5.1% ± 5.3%, while Bland-Altman analyses revealed very low differences in mean DVR (e.g. 0.013 ± 0.17 for the nucleus accumbens). Intraclass correlation (one-way, random) indicated very high agreement (0.93 in average) for both DVR and BP{sub ND} values. Accordingly, the absolute variability of BP{sub ND} ranged from 7.0% ± 4.7% to 12.5% ± 10.6%; however, there were regions with very low D{sub 1}R content, such as the occipital cortex, with higher mean variability. The test-retest reliability of D{sub 1}R measurements in this study was very high. This was the case not only for D{sub 1}R-rich brain areas, but

  9. Open solar flux estimates from near-Earth measurements of the interplanetary magnetic field: comparison of the first two perihelion passes of the Ulysses spacecraft

    M. Lockwood

    2004-04-01

    Full Text Available Results from all phases of the orbits of the Ulysses spacecraft have shown that the magnitude of the radial component of the heliospheric field is approximately independent of heliographic latitude. This result allows the use of near-Earth observations to compute the total open flux of the Sun. For example, using satellite observations of the interplanetary magnetic field, the average open solar flux was shown to have risen by 29% between 1963 and 1987 and using the aa geomagnetic index it was found to have doubled during the 20th century. It is therefore important to assess fully the accuracy of the result and to check that it applies to all phases of the solar cycle. The first perihelion pass of the Ulysses spacecraft was close to sunspot minimum, and recent data from the second perihelion pass show that the result also holds at solar maximum. The high level of correlation between the open flux derived from the various methods strongly supports the Ulysses discovery that the radial field component is independent of latitude. We show here that the errors introduced into open solar flux estimates by assuming that the heliospheric field's radial component is independent of latitude are similar for the two passes and are of order 25% for daily values, falling to 5% for averaging timescales of 27 days or greater. We compare here the results of four methods for estimating the open solar flux with results from the first and second perehelion passes by Ulysses. We find that the errors are lowest (1–5% for averages over the entire perehelion passes lasting near 320 days, for near-Earth methods, based on either interplanetary magnetic field observations or the aa geomagnetic activity index. The corresponding errors for the Solanki et al. (2000 model are of the order of 9–15% and for the PFSS method, based on solar magnetograms, are of the order of 13–47%. The model of Solanki et al. is based on the continuity equation of open flux, and uses the

  10. Simultaneous measurement of two enzyme activities using infrared spectroscopy: A comparative evaluation of PARAFAC, TUCKER and N-PLS modeling

    Baum, Andreas; Hansen, Per Waaben; Meyer, Anne S.

    2013-01-01

    multiway methods, namely PARAFAC, TUCKER3 and N-PLS, to establish simultaneous enzyme activity assays for pectin lyase and pectin methyl esterase. Correlation coefficients Rpred2 for prediction test sets are 0.48, 0.96 and 0.96 for pectin lyase and 0.70, 0.89 and 0.89 for pectin methyl esterase......Enzymes are used in many processes to release fermentable sugars for green production of biofuel, or the refinery of biomass for extraction of functional food ingredients such as pectin or prebiotic oligosaccharides. The complex biomasses may, however, require a multitude of specific enzymes which...... are active on specific substrates generating a multitude of products. In this paper we use the plant polymer, pectin, to present a method to quantify enzyme activity of two pectolytic enzymes by monitoring their superimposed spectral evolutions simultaneously. The data is analyzed by three chemometric...

  11. Event-triggered attitude control of spacecraft

    Wu, Baolin; Shen, Qiang; Cao, Xibin

    2018-02-01

    The problem of spacecraft attitude stabilization control system with limited communication and external disturbances is investigated based on an event-triggered control scheme. In the proposed scheme, information of attitude and control torque only need to be transmitted at some discrete triggered times when a defined measurement error exceeds a state-dependent threshold. The proposed control scheme not only guarantees that spacecraft attitude control errors converge toward a small invariant set containing the origin, but also ensures that there is no accumulation of triggering instants. The performance of the proposed control scheme is demonstrated through numerical simulation.

  12. Long-term survey of lion-roar emissions inside the terrestrial magnetosheath obtained from the STAFF-SA measurements onboard the Cluster spacecraft

    Pisa, D.; Krupar, V.; Kruparova, O.; Santolik, O.

    2017-12-01

    Intense whistler-mode emissions known as 'lion-roars' are often observed inside the terrestrial magnetosheath, where the solar wind plasma flow slows down, and the local magnetic field increases ahead of a planetary magnetosphere. Plasma conditions in this transient region lead to the electron temperature anisotropy, which can result in the whistler-mode waves. The lion-roars are narrow-band emissions with typical frequencies between 0.1-0.5 Fce, where Fce is the electron cyclotron frequency. We present results of a long-term survey obtained by the Spatio Temporal Analysis Field Fluctuations - Spectral Analyzer (STAFF-SA) instruments on board the four Cluster spacecraft between 2001 and 2010. We have visually identified the time-frequency intervals with the intense lion-roar signature. Using the Singular Value Decomposition (SVD) method, we analyzed the wave propagation properties. We show the spatial, frequency and wave power distributions. Finally, the wave properties as a function of upstream solar wind conditions are discussed.

  13. Low power arcjet system spacecraft impacts

    Pencil, Eric J.; Sarmiento, Charles J.; Lichtin, D. A.; Palchefsky, J. W.; Bogorad, A. L.

    1993-01-01

    Potential plume contamination of spacecraft surfaces was investigated by positioning spacecraft material samples relative to an arcjet thruster. Samples in the simulated solar array region were exposed to the cold gas arcjet plume for 40 hrs to address concerns about contamination by backstreaming diffusion pump oil. Except for one sample, no significant changes were measured in absorptance and emittance within experimental error. Concerns about surface property degradation due to electrostatic discharges led to the investigation of the discharge phenomenon of charged samples during arcjet ignition. Short duration exposure of charged samples demonstrated that potential differences are consistently and completely eliminated within the first second of exposure to a weakly ionized plume. The spark discharge mechanism was not the discharge phenomenon. The results suggest that the arcjet could act as a charge control device on spacecraft.

  14. X-Ray Detection and Processing Models for Spacecraft Navigation and Timing

    Sheikh, Suneel; Hanson, John

    2013-01-01

    The current primary method of deepspace navigation is the NASA Deep Space Network (DSN). High-performance navigation is achieved using Delta Differential One-Way Range techniques that utilize simultaneous observations from multiple DSN sites, and incorporate observations of quasars near the line-of-sight to a spacecraft in order to improve the range and angle measurement accuracies. Over the past four decades, x-ray astronomers have identified a number of xray pulsars with pulsed emissions having stabilities comparable to atomic clocks. The x-ray pulsar-based navigation and time determination (XNAV) system uses phase measurements from these sources to establish autonomously the position of the detector, and thus the spacecraft, relative to a known reference frame, much as the Global Positioning System (GPS) uses phase measurements from radio signals from several satellites to establish the position of the user relative to an Earth-centered fixed frame of reference. While a GPS receiver uses an antenna to detect the radio signals, XNAV uses a detector array to capture the individual xray photons from the x-ray pulsars. The navigation solution relies on detailed xray source models, signal processing, navigation and timing algorithms, and analytical tools that form the basis of an autonomous XNAV system. Through previous XNAV development efforts, some techniques have been established to utilize a pulsar pulse time-of-arrival (TOA) measurement to correct a position estimate. One well-studied approach, based upon Kalman filter methods, optimally adjusts a dynamic orbit propagation solution based upon the offset in measured and predicted pulse TOA. In this delta position estimator scheme, previously estimated values of spacecraft position and velocity are utilized from an onboard orbit propagator. Using these estimated values, the detected arrival times at the spacecraft of pulses from a pulsar are compared to the predicted arrival times defined by the pulsar s pulse

  15. METHOD FOR SIMULTANEOUS 90SR AND 137CS IN-VIVO MEASUREMENTS OF SMALL ANIMALS AND OTHER ENVIRONMENTAL MEDIA DEVELOPED FOR THE CONDITIONS OF THE CHERNOBYL EXCLUSION ZONE

    Farfan, E.; Jannik, T.

    2011-10-01

    To perform in vivo simultaneous measurements of the {sup 90}Sr and {sup 137}Cs content in the bodies of animals living in the Chernobyl Exclusion Zone (ChEZ), an appropriate method and equipment were developed and installed in a mobile gamma beta spectrometry laboratory. This technique was designed for animals of relatively small sizes (up to 50 g). The {sup 90}Sr content is measured by a beta spectrometer with a 0.1 mm thick scintillation plastic detector. The spectrum processing takes into account the fact that the measured object is 'thick-layered' and contains a comparable quantity of {sup 137}Cs, which is a characteristic condition of the ChEZ. The {sup 137}Cs content is measured by a NaI scintillation detector that is part of the combined gamma beta spectrometry system. For environmental research performed in the ChEZ, the advantages of this method and equipment (rapid measurements, capability to measure live animals directly in their habitat, and the capability of simultaneous {sup 90}Sr and {sup 137}Cs measurements) far outweigh the existing limitations (considerations must be made for background radiation and the animal size, skeletal shape and body mass). The accuracy of these in vivo measurements is shown to be consistent with standard spectrometric and radiochemical methods. Apart from the in vivo measurements, the proposed methodology, after a very simple upgrade that is also described in the article, works even more accurately with samples of other media, such as soil and plants.

  16. Experiments study on attitude coupling control method for flexible spacecraft

    Wang, Jie; Li, Dongxu

    2018-06-01

    High pointing accuracy and stabilization are significant for spacecrafts to carry out Earth observing, laser communication and space exploration missions. However, when a spacecraft undergoes large angle maneuver, the excited elastic oscillation of flexible appendages, for instance, solar wing and onboard antenna, would downgrade the performance of the spacecraft platform. This paper proposes a coupling control method, which synthesizes the adaptive sliding mode controller and the positive position feedback (PPF) controller, to control the attitude and suppress the elastic vibration simultaneously. Because of its prominent performance for attitude tracking and stabilization, the proposed method is capable of slewing the flexible spacecraft with a large angle. Also, the method is robust to parametric uncertainties of the spacecraft model. Numerical simulations are carried out with a hub-plate system which undergoes a single-axis attitude maneuver. An attitude control testbed for the flexible spacecraft is established and experiments are conducted to validate the coupling control method. Both numerical and experimental results demonstrate that the method discussed above can effectively decrease the stabilization time and improve the attitude accuracy of the flexible spacecraft.

  17. Formation process of hierarchical structures in crystalline polymers as analyzed by simultaneous measurements of small-angle X-ray scattering and other techniques

    Yamamoto, Katsuhiro; Sakurai, Shinichi

    2006-01-01

    Crystalline polymers spontaneously form hierarchical structures, which provide us a potential use as a specialty material. Recently, not only a crystalline homopolymer but also semi-crystalline block copolymers and crystalline polymer blends have been attracting interests for the study of a hierarchical structure. In order to analyze such hierarchical structures in a variety of length scales, a simultaneous measurement of small-(SAXS) and wide-angle (WAXS) X-ray scattering with differential scanning calorimetry (DSC), or with small-angle light scattering (Hv-SALS) are most suitable. In this review, we show some examples of the simultaneous measurements. With DSC, exothermic heat flow can be simultaneously measured with X-ray scattering. On the other hand, with Hv-SALS it is possible to analyze evolution of a spherulitic structure, which is the structure at the highest rank in the hierarchy. For both cases, one can realize that it is impossible to obtain good statistics for SAXS and WAXS measurements without synchrotron radiations. (author)

  18. Technical note: Evaluation of the simultaneous measurements of mesospheric OH, HO2, and O3 under a photochemical equilibrium assumption - a statistical approach

    Kulikov, Mikhail Y.; Nechaev, Anton A.; Belikovich, Mikhail V.; Ermakova, Tatiana S.; Feigin, Alexander M.

    2018-05-01

    This Technical Note presents a statistical approach to evaluating simultaneous measurements of several atmospheric components under the assumption of photochemical equilibrium. We consider simultaneous measurements of OH, HO2, and O3 at the altitudes of the mesosphere as a specific example and their daytime photochemical equilibrium as an evaluating relationship. A simplified algebraic equation relating local concentrations of these components in the 50-100 km altitude range has been derived. The parameters of the equation are temperature, neutral density, local zenith angle, and the rates of eight reactions. We have performed a one-year simulation of the mesosphere and lower thermosphere using a 3-D chemical-transport model. The simulation shows that the discrepancy between the calculated evolution of the components and the equilibrium value given by the equation does not exceed 3-4 % in the full range of altitudes independent of season or latitude. We have developed a statistical Bayesian evaluation technique for simultaneous measurements of OH, HO2, and O3 based on the equilibrium equation taking into account the measurement error. The first results of the application of the technique to MLS/Aura data (Microwave Limb Sounder) are presented in this Technical Note. It has been found that the satellite data of the HO2 distribution regularly demonstrate lower altitudes of this component's mesospheric maximum. This has also been confirmed by model HO2 distributions and comparison with offline retrieval of HO2 from the daily zonal means MLS radiance.

  19. A spin-optoelectronic detector for the simultaneous measurement of the degree of circular polarization and intensity of a laser beam

    Khamari, Shailesh K.; Porwal, S.; Oak, S. M.; Sharma, T. K.

    2015-01-01

    Simultaneous measurement of the degree of circular polarization and intensity of a laser beam is essential in advanced photonic applications. However, it is not feasible with conventional helicity dependent detectors where an additional detector is needed to measure the intensity. Here, we report the development of a spin-optoelectronic detector that can measure the degree of circular polarization and the intensity of a laser beam simultaneously. The principle of operation of device is based on the two independent fundamental phenomena occurring in Au/InP hybrid structures, namely, Inverse Spin Hall Effect (ISHE) and the Photo-Voltaic (PV) Effect. The magnitude of ISHE and PV signals is simultaneously measured across the two pairs of contacts that are made on the top of device. No cross talk is observed between the two detectors made on the same chip. The all-electronic compact device is fast, operates at room temperature, and opens up the possibility of many applications in an integrated optoelectronic platform

  20. A low-cost, high-performance, digital signal processor-based lock-in amplifier capable of measuring multiple frequency sweeps simultaneously

    Sonnaillon, Maximiliano Osvaldo; Bonetto, Fabian Jose

    2005-01-01

    A high-performance digital lock-in amplifier implemented in a low-cost digital signal processor (DSP) board is described. This lock in is capable of measuring simultaneously multiple frequencies that change in time as frequency sweeps (chirps). The used 32-bit DSP has enough computing power to generate N=3 simultaneous reference signals and accurately measure the N=3 responses, operating as three lock ins connected in parallel to a linear system. The lock in stores the measured values in memory until they are downloaded to the a personal computer (PC). The lock in works in stand-alone mode and can be programmed and configured through the PC serial port. Downsampling and multiple filter stages were used in order to obtain a sharp roll off and a long time constant in the filters. This makes measurements possible in presence of high-noise levels. Before each measurement, the lock in performs an autocalibration that measures the frequency response of analog output and input circuitry in order to compensate for the departure from ideal operation. Improvements from previous lock-in implementations allow measuring the frequency response of a system in a short time. Furthermore, the proposed implementation can measure how the frequency response changes with time, a characteristic that is very important in our biotechnological application. The number of simultaneous components that the lock in can generate and measure can be extended, without reprogramming, by only using other DSPs of the same family that are code compatible and work at higher clock frequencies

  1. A low-cost, high-performance, digital signal processor-based lock-in amplifier capable of measuring multiple frequency sweeps simultaneously

    Sonnaillon, Maximiliano Osvaldo; Bonetto, Fabian Jose [Laboratorio de Cavitacion y Biotecnologia, San Carlos de Bariloche (8400) (Argentina)

    2005-02-01

    A high-performance digital lock-in amplifier implemented in a low-cost digital signal processor (DSP) board is described. This lock in is capable of measuring simultaneously multiple frequencies that change in time as frequency sweeps (chirps). The used 32-bit DSP has enough computing power to generate N=3 simultaneous reference signals and accurately measure the N=3 responses, operating as three lock ins connected in parallel to a linear system. The lock in stores the measured values in memory until they are downloaded to the a personal computer (PC). The lock in works in stand-alone mode and can be programmed and configured through the PC serial port. Downsampling and multiple filter stages were used in order to obtain a sharp roll off and a long time constant in the filters. This makes measurements possible in presence of high-noise levels. Before each measurement, the lock in performs an autocalibration that measures the frequency response of analog output and input circuitry in order to compensate for the departure from ideal operation. Improvements from previous lock-in implementations allow measuring the frequency response of a system in a short time. Furthermore, the proposed implementation can measure how the frequency response changes with time, a characteristic that is very important in our biotechnological application. The number of simultaneous components that the lock in can generate and measure can be extended, without reprogramming, by only using other DSPs of the same family that are code compatible and work at higher clock frequencies.

  2. Simultaneous radiochemotherapy

    Dunst, J.; Sauer, R.

    1993-01-01

    Simultaneous radiochemotherapy (RCT) means the simultaneous application of radiotherapy and chemotherapy. The major objective of this approach is the improvement of local control. On the cellular level, three types of interactions may be distinguished: Additivity, synergism, and sensibilization. The main type of interaction seems to be a simple additive effect. The clinical effect of a simultaneous chemotherapy depends mainly on the cytotoxic action of the drug itself and not on radiosensibilization. Therefore, effective chemotherapeutic drugs are to be delivered in cytotoxic dosages in RCT protocols. Compromises in radiotherapy as the main modality should be avoided. Recent clinical data have shown that simultaneous radiochemotherapy may yield heigh remission rates in a number of tumor entities (e.g. anal cancer, bladder cancer, head and neck cancer). This seems to improve local control as compared to radiotherapy alone. In some tumors (e.g. head and neck, esophagus), survival may be improved also. However, several questions require future detailed clinical trials. These questions include the value of simultaneous radiochemotherapy compared to optimal fractionation schemes, the clear definition of subgroups of patients with benefit by radiochemotherapy and the optimal dose intensity of cytotoxic drugs. (orig.) [de

  3. Simultaneous UV Imaging and Raman Spectroscopy for the Measurement of Solvent-Mediated Phase Transformations During Dissolution Testing

    Ostergaard, Jesper; Wu, Jian; Naelapää, Kaisa

    2014-01-01

    The current work reports the simultaneous use of UV imaging and Raman spectroscopy for detailed characterization of drug dissolution behavior including solid-state phase transformations during dissolution. The dissolution of drug substances from compacts of sodium naproxen in 0.1 HCl as well as t...... of UV imaging and Raman spectroscopy offers a detailed characterization of drug dissolution behavior in a time-effective and sample-sparing manner. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:1149-1156, 2014....

  4. Simultaneous measurement of local particle movement, solids concentrations and bubble properties in fluidized bed reactors using a novel fiber optical technique

    Tayebi, Davoud

    1999-12-31

    This thesis develops a new method for simultaneous measurements of local flow properties in highly concentrated multiphase flow systems such as gas-solid fluidized bed reactors. The method is based on fiber optical technique and tracer particles. A particle present in the measuring volume in front of the probe is marked with a fluorescent dye. A light source illuminates the particles and the detecting fibres receive reflected light from uncoated particles and fluorescent light from the tracer particle. Using optical filters, the fluorescent light can be distinguished and together with a small fraction of background light from uncoated particles can be used for determination of local flow properties. Using this method, one can simultaneously measure the local movement of a single tracer particle, local bubble properties and the local solids volume fractions in different positions in the bed. The method is independent of the physical properties of the tracer particles. It is also independent of the local solids concentrations in the range of 0 to 60 vol.-%, but is mainly designed for highly concentrated flow systems. A computer programme that uses good signals from at least three sensors simultaneously to calculate the tracer particle velocity in two dimensions have been developed. It also calculates the bubble properties and local solids volume fractions from the same time series. 251 refs., 150 figs., 5 tabs.

  5. Multivariate analysis of DSC-XRD simultaneous measurement data: a study of multistage crystalline structure changes in a linear poly(ethylene imine) thin film.

    Kakuda, Hiroyuki; Okada, Tetsuo; Otsuka, Makoto; Katsumoto, Yukiteru; Hasegawa, Takeshi

    2009-01-01

    A multivariate analytical technique has been applied to the analysis of simultaneous measurement data from differential scanning calorimetry (DSC) and X-ray diffraction (XRD) in order to study thermal changes in crystalline structure of a linear poly(ethylene imine) (LPEI) film. A large number of XRD patterns generated from the simultaneous measurements were subjected to an augmented alternative least-squares (ALS) regression analysis, and the XRD patterns were readily decomposed into chemically independent XRD patterns and their thermal profiles were also obtained at the same time. The decomposed XRD patterns and the profiles were useful in discussing the minute peaks in the DSC. The analytical results revealed the following changes of polymorphisms in detail: An LPEI film prepared by casting an aqueous solution was composed of sesquihydrate and hemihydrate crystals. The sesquihydrate one was lost at an early stage of heating, and the film changed into an amorphous state. Once the sesquihydrate was lost by heating, it was not recovered even when it was cooled back to room temperature. When the sample was heated again, structural changes were found between the hemihydrate and the amorphous components. In this manner, the simultaneous DSC-XRD measurements combined with ALS analysis proved to be powerful for obtaining a better understanding of the thermally induced changes of the crystalline structure in a polymer film.

  6. A correlative study of simultaneously measured He(++) fluxes in the solar wind and in the magnetosphere utilizing Imp-1 and 1971-089A satellite data

    Shelley, E. G.

    1975-01-01

    Simultaneously measured He(++) fluxes in the solar wind and in the magnetosphere were studied using data from the plasma spectrometer on the Imp I satellite and the energetic ion mass spectrometer on the low altitude polar orbiting satellite 1971-89A. A detailed comparison of the He(++) energy spectra measured simultaneously in the solar wind and in the low altitude dayside polar cusp on March 7, 1972 was made. The energy-per-unit-charge range of the energetic ion mass spectrometer on board the polar orbiting satellite was 700 eV to 12 keV. Within this range there was a clear maximum in the He(++) energy spectrum at approximately 1.5 keV/nucleon. There was not a clearly defined maximum in the H(+) spectrum, but the data were consistent with a peak between 0.7 and 1.0 keV/nucleon. Both spectra could be reasonably well fit with a convecting Maxwellian plus a high energy tail; however, the mean velocity for He(++) distribution was significantly greater than that for the H(+) distribution. The simultaneous solar wind measurements showed the mean velocities for both ion species to be approximately 600 km/sec. The discrepancies between the relative velocity distributions in the low altitude cusp and those in the solar wind are consistent with a potential difference of approximately 1.4 kV along their flow direction between the two points of observation.

  7. Simultaneous measurement of local particle movement, solids concentrations and bubble properties in fluidized bed reactors using a novel fiber optical technique

    Tayebi, Davoud

    1998-12-31

    This thesis develops a new method for simultaneous measurements of local flow properties in highly concentrated multiphase flow systems such as gas-solid fluidized bed reactors. The method is based on fiber optical technique and tracer particles. A particle present in the measuring volume in front of the probe is marked with a fluorescent dye. A light source illuminates the particles and the detecting fibres receive reflected light from uncoated particles and fluorescent light from the tracer particle. Using optical filters, the fluorescent light can be distinguished and together with a small fraction of background light from uncoated particles can be used for determination of local flow properties. Using this method, one can simultaneously measure the local movement of a single tracer particle, local bubble properties and the local solids volume fractions in different positions in the bed. The method is independent of the physical properties of the tracer particles. It is also independent of the local solids concentrations in the range of 0 to 60 vol.-%, but is mainly designed for highly concentrated flow systems. A computer programme that uses good signals from at least three sensors simultaneously to calculate the tracer particle velocity in two dimensions have been developed. It also calculates the bubble properties and local solids volume fractions from the same time series. 251 refs., 150 figs., 5 tabs.

  8. Simultaneous measurement of two enzyme activities using infrared spectroscopy: A comparative evaluation of PARAFAC, TUCKER and N-PLS modeling.

    Baum, Andreas; Hansen, Per Waaben; Meyer, Anne S; Mikkelsen, Jørn Dalgaard

    2013-08-06

    Enzymes are used in many processes to release fermentable sugars for green production of biofuel, or the refinery of biomass for extraction of functional food ingredients such as pectin or prebiotic oligosaccharides. The complex biomasses may, however, require a multitude of specific enzymes which are active on specific substrates generating a multitude of products. In this paper we use the plant polymer, pectin, to present a method to quantify enzyme activity of two pectolytic enzymes by monitoring their superimposed spectral evolutions simultaneously. The data is analyzed by three chemometric multiway methods, namely PARAFAC, TUCKER3 and N-PLS, to establish simultaneous enzyme activity assays for pectin lyase and pectin methyl esterase. Correlation coefficients Rpred(2) for prediction test sets are 0.48, 0.96 and 0.96 for pectin lyase and 0.70, 0.89 and 0.89 for pectin methyl esterase, respectively. The retrieved models are compared and prediction test sets show that especially TUCKER3 performs well, even in comparison to the supervised regression method N-PLS. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Co-transcriptomic Analysis by RNA Sequencing to Simultaneously Measure Regulated Gene Expression in Host and Bacterial Pathogen

    Ravasi, Timothy; Mavromatis, Charalampos Harris; Bokil, Nilesh J.; Schembri, Mark A.; Sweet, Matthew J.

    2016-01-01

    Intramacrophage pathogens subvert antimicrobial defence pathways using various mechanisms, including the targeting of host TLR-mediated transcriptional responses. Conversely, TLR-inducible host defence mechanisms subject intramacrophage pathogens to stress, thus altering pathogen gene expression programs. Important biological insights can thus be gained through the analysis of gene expression changes in both the host and the pathogen during an infection. Traditionally, research methods have involved the use of qPCR, microarrays and/or RNA sequencing to identify transcriptional changes in either the host or the pathogen. Here we describe the application of RNA sequencing using samples obtained from in vitro infection assays to simultaneously quantify both host and bacterial pathogen gene expression changes, as well as general approaches that can be undertaken to interpret the RNA sequencing data that is generated. These methods can be used to provide insights into host TLR-regulated transcriptional responses to microbial challenge, as well as pathogen subversion mechanisms against such responses.

  10. Co-transcriptomic Analysis by RNA Sequencing to Simultaneously Measure Regulated Gene Expression in Host and Bacterial Pathogen

    Ravasi, Timothy

    2016-01-24

    Intramacrophage pathogens subvert antimicrobial defence pathways using various mechanisms, including the targeting of host TLR-mediated transcriptional responses. Conversely, TLR-inducible host defence mechanisms subject intramacrophage pathogens to stress, thus altering pathogen gene expression programs. Important biological insights can thus be gained through the analysis of gene expression changes in both the host and the pathogen during an infection. Traditionally, research methods have involved the use of qPCR, microarrays and/or RNA sequencing to identify transcriptional changes in either the host or the pathogen. Here we describe the application of RNA sequencing using samples obtained from in vitro infection assays to simultaneously quantify both host and bacterial pathogen gene expression changes, as well as general approaches that can be undertaken to interpret the RNA sequencing data that is generated. These methods can be used to provide insights into host TLR-regulated transcriptional responses to microbial challenge, as well as pathogen subversion mechanisms against such responses.

  11. First simultaneous measurements of waves generated at the bow shock in the solar wind, the magnetosphere and on the ground

    Clausen, L. B. N.; Yeoman, T. K.; Fear, R. C.; Behlke, R.; Lucek, E. A.; Engebretson, M. J.

    2009-01-01

    On 5 September 2002 the Geotail satellite observed the cone angle of the Interplanetary Magnetic Field (IMF) change to values below 30° during a 56 min interval between 18:14 and 19:10 UT. This triggered the generation of upstream waves at the bow shock, 13 RE downstream of the position of Geotail. Upstream generated waves were subsequently observed by Geotail between 18:30 and 18:48 UT, during times the IMF cone angle dropped below values of 10°. At 18:24 UT all four Cluster satellites simultaneously observed a sudden increase in wave power in all three magnetic field components, independent of their position in the dayside magnetosphere. We show that the 10 min delay between the change in IMF direction as observed by Geotail and the increase in wave power observed by Cluster is consistent with the propagation of the IMF change from the Geotail position to the bow shock and the propagation of the generated waves through the bow shock, magnetosheath and magnetosphere towards the position of the Cluster satellites. We go on to show that the wave power recorded by the Cluster satellites in the component containing the poloidal and compressional pulsations was broadband and unstructured; the power in the component containing toroidal oscillations was structured and shows the existence of multi-harmonic Alfvénic continuum waves on field lines. Model predictions of these frequencies fit well with the observations. An increase in wave power associated with the change in IMF direction was also registered by ground based magnetometers which were magnetically conjunct with the Cluster satellites during the event. To the best of our knowledge we present the first simultaneous observations of waves created by backstreaming ions at the bow shock in the solar wind, the dayside magnetosphere and on the ground.

  12. Small Spacecraft for Planetary Science

    Baker, John; Castillo-Rogez, Julie; Bousquet, Pierre-W.; Vane, Gregg; Komarek, Tomas; Klesh, Andrew

    2016-07-01

    As planetary science continues to explore new and remote regions of the Solar system with comprehensive and more sophisticated payloads, small spacecraft offer the possibility for focused and more affordable science investigations. These small spacecraft or micro spacecraft (attitude control and determination, capable computer and data handling, and navigation are being met by technologies currently under development to be flown on CubeSats within the next five years. This paper will discuss how micro spacecraft offer an attractive alternative to accomplish specific science and technology goals and what relevant technologies are needed for these these types of spacecraft. Acknowledgements: Part of this work is being carried out at the Jet Propulsion Laboratory, California Institute of Technology under contract to NASA. Government sponsorship acknowledged.

  13. Simultaneous measurement of instantaneous heart rate and chest wall plethysmography in short-term, metronome guided heart rate variability studies: suitability for assessment of autonomic dysfunction.

    Perring, S; Jones, E

    2003-08-01

    Instantaneous heart rate and chest wall motion were measured using a 3-lead ECG and an air pressure chest wall plethysmography system. Chest wall plethysmography traces were found to accurately represent the breathing pattern as measured by spirometry (average correlation coefficient 0.944); though no attempt was made to calibrate plethysmography voltage output to tidal volume. Simultaneous measurements of heart rate and chest wall motion were made for short periods under metronome guided breathing at 6 breaths per minute. The average peak to trough heart rate change per breath cycle (AVEMAX) and maximum correlation between heart rate and breathing cycle (HRBRCORR) were measured. Studies of 44 normal volunteers indicated clear inverse correlation of heart rate variability parameters with age (AVEMAX R = -0.502, P < 0.001) but no significant change in HRBRCORR with age (R = -0.115). Comparison of normal volunteers with diabetics with no history of symptoms associated with autonomic failure indicated significant lower heart rate variability in diabetics (P = 0.005 for AVEMAX) and significantly worse correlation between heart rate and breathing (P < 0.001 for HRBRCORR). Simultaneous measurement of heart rate and breathing offers the possibility of more sensitive diagnosis of autonomic failure in a simple bedside test and gives further insight into the nature of cardio-ventilatory coupling.

  14. Simultaneous measurement of milk intake and total energy expenditure in mixed-fed infants: Methodological approach and prediction of total body water

    Wells, J.C.K.; Davies, P.S.W.; Coward, W.A.

    2000-01-01

    Evaluation of the energy metabolism that underlies the new WHO breast-fed growth reference requires simultaneous measurements of milk volume intake (MVI) and total energy expenditure (TEE) by stable isotope methodologies. In young infants, such data is collected without difficulty using the dose-to-the-infant method. In older infants, where breast-milk is supplemented with non-milk foods, MVI must be measured by dosing the mother instead of the infant. This procedure would interfere with a simple measurement of infant TEE using the standard dose-to-the-infant method. Theoretically, this difficulty can be resolved by dosing the mother with deuterium and the infant with 18-oxygen, and using curve-peeling methods to calculate the infant deuterium kinetics. We propose to ascertain whether such an approach is viable in practice, such that MVI, TEE and body composition could all be measured simultaneously in mixed-fed infants. Where MVI in older infants is measured on its own, there is a need to predict infant body water in order to estimate the deuterium dilution space. Using a database of 234 infants aged 1.5 to 12 months, we provide new predictive equations by which such values may be obtained. (author)

  15. Note: Application of a pixel-array area detector to simultaneous single crystal x-ray diffraction and x-ray absorption spectroscopy measurements

    Sun, Cheng-Jun; Brewe, Dale L.; Heald, Steve M.; Zhang, Bangmin; Chen, Jing-Sheng; Chow, G. M.; Venkatesan, T.

    2014-01-01

    X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) are two main x-ray techniques in synchrotron radiation facilities. In this Note, we present an experimental setup capable of performing simultaneous XRD and XAS measurements by the application of a pixel-array area detector. For XRD, the momentum transfer in specular diffraction was measured by scanning the X-ray energy with fixed incoming and outgoing x-ray angles. By selecting a small fixed region of the detector to collect the XRD signal, the rest of the area was available for collecting the x-ray fluorescence for XAS measurements. The simultaneous measurement of XRD and X-ray absorption near edge structure for Pr 0.67 Sr 0.33 MnO 3 film was demonstrated as a proof of principle for future time-resolved pump-probe measurements. A static sample makes it easy to maintain an accurate overlap of the X-ray spot and laser pump beam

  16. Printed Spacecraft Separation System

    Dehoff, Ryan R [ORNL; Holmans, Walter [Planetary Systems Corporation

    2016-10-01

    In this project Planetary Systems Corporation proposed utilizing additive manufacturing (3D printing) to manufacture a titanium spacecraft separation system for commercial and US government customers to realize a 90% reduction in the cost and energy. These savings were demonstrated via “printing-in” many of the parts and sub-assemblies into one part, thus greatly reducing the labor associated with design, procurement, assembly and calibration of mechanisms. Planetary Systems Corporation redesigned several of the components of the separation system based on additive manufacturing principles including geometric flexibility and the ability to fabricate complex designs, ability to combine multiple parts of an assembly into a single component, and the ability to optimize design for specific mechanical property targets. Shock absorption was specifically targeted and requirements were established to attenuate damage to the Lightband system from shock of initiation. Planetary Systems Corporation redesigned components based on these requirements and sent the designs to Oak Ridge National Laboratory to be printed. ORNL printed the parts using the Arcam electron beam melting technology based on the desire for the parts to be fabricated from Ti-6Al-4V based on the weight and mechanical performance of the material. A second set of components was fabricated from stainless steel material on the Renishaw laser powder bed technology due to the improved geometric accuracy, surface finish, and wear resistance of the material. Planetary Systems Corporation evaluated these components and determined that 3D printing is potentially a viable method for achieving significant cost and savings metrics.

  17. Spectra and spacecraft

    Moroz, V. I.

    2001-02-01

    In June 1999, Dr. Regis Courtin, Associate Editor of PSS, suggested that I write an article for the new section of this journal: "Planetary Pioneers". I hesitated , but decided to try. One of the reasons for my doubts was my primitive English, so I owe the reader an apology for this in advance. Writing took me much more time than I supposed initially, I have stopped and again returned to manuscript many times. My professional life may be divided into three main phases: pioneering work in ground-based IR astronomy with an emphasis on planetary spectroscopy (1955-1970), studies of the planets with spacecraft (1970-1989), and attempts to proceed with this work in difficult times. I moved ahead using the known method of trials and errors as most of us do. In fact, only a small percentage of efforts led to some important results, a sort of dry residue. I will try to describe below how has it been in my case: what may be estimated as the most important, how I came to this, what was around, etc.

  18. Close-Range Photogrammetry & Next Generation Spacecraft

    Pappa, Richard S.

    2002-01-01

    NASA is focusing renewed attention on the topic of large, ultra-lightweight space structures, also known as 'gossamer' spacecraft. Nearly all of the details of the giant spacecraft are still to be worked out. But it's already clear that one of the most challenging aspects will be developing techniques to align and control these systems after they are deployed in space. A critical part of this process is creating new ground test methods to measure gossamer structures under stationary, deploying and vibrating conditions for validation of corresponding analytical predictions. In addressing this problem, I considered, first of all, the possibility of simply using conventional displacement or vibration sensor that could provide spatial measurements. Next, I turned my attention to photogrammetry, a method of determining the spatial coordinates of objects using photographs. The success of this research and development has convinced me that photogrammetry is the most suitable method to solve the gossamer measurement problem.

  19. Streamlined Modeling for Characterizing Spacecraft Anomalous Behavior

    Klem, B.; Swann, D.

    2011-09-01

    Anomalous behavior of on-orbit spacecraft can often be detected using passive, remote sensors which measure electro-optical signatures that vary in time and spectral content. Analysts responsible for assessing spacecraft operational status and detecting detrimental anomalies using non-resolved imaging sensors are often presented with various sensing and identification issues. Modeling and measuring spacecraft self emission and reflected radiant intensity when the radiation patterns exhibit a time varying reflective glint superimposed on an underlying diffuse signal contribute to assessment of spacecraft behavior in two ways: (1) providing information on body component orientation and attitude; and, (2) detecting changes in surface material properties due to the space environment. Simple convex and cube-shaped spacecraft, designed to operate without protruding solar panel appendages, may require an enhanced level of preflight characterization to support interpretation of the various physical effects observed during on-orbit monitoring. This paper describes selected portions of the signature database generated using streamlined signature modeling and simulations of basic geometry shapes apparent to non-imaging sensors. With this database, summarization of key observable features for such shapes as spheres, cylinders, flat plates, cones, and cubes in specific spectral bands that include the visible, mid wave, and long wave infrared provide the analyst with input to the decision process algorithms contained in the overall sensing and identification architectures. The models typically utilize baseline materials such as Kapton, paints, aluminum surface end plates, and radiators, along with solar cell representations covering the cylindrical and side portions of the spacecraft. Multiple space and ground-based sensors are assumed to be located at key locations to describe the comprehensive multi-viewing aspect scenarios that can result in significant specular reflection

  20. Simultaneous current, force and dissipation measurements on the Si(111 7×7 surface with an optimized qPlus AFM/STM technique

    Zsolt Majzik

    2012-03-01

    Full Text Available We present the results of simultaneous scanning-tunneling and frequency-modulated dynamic atomic force microscopy measurements with a qPlus setup. The qPlus sensor is a purely electrical sensor based on a quartz tuning fork. If both the tunneling current and the force signal are to be measured at the tip, a cross-talk of the tunneling current with the force signal can easily occur. The origin and general features of the capacitive cross-talk will be discussed in detail in this contribution. Furthermore, we describe an experimental setup that improves the level of decoupling between the tunneling-current and the deflection signal. The efficiency of this experimental setup is demonstrated through topography and site-specific force/tunneling-spectroscopy measurements on the Si(111 7×7 surface. The results show an excellent agreement with previously reported data measured by optical interferometric deflection.

  1. Simultaneous measurement of internal and surrounding flows of a moving droplet using multicolour confocal micro-particle image velocimetry (micro-PIV)

    Oishi, M; Kinoshita, H; Fujii, T; Oshima, M

    2011-01-01

    This paper presents a micro-multiphase flow measurement technique, 'multicolour confocal micro-particle image velocimetry (PIV), and its application to the internal and surrounding flow measurement of a droplet moving through a microchannel. The present system measures the dynamic interaction between flows in two different phases, such as solid–liquid or liquid–liquid, simultaneously and separately. Unlike conventional confocal micro-PIV, this system features a wavelength separation optical device. The optical components (e.g., filters and dichroic mirror) are designed to separate fluorescent lights of tracer particles and to eliminate unnecessary scattered light depending on the characteristic wavelengths. The system can record a sequence of images at up to 2000 frames per second. It also has an in-plane spatial resolution of 0.284 µm/pixel in a field of 227.2 µm × 170.4 µm and a confocal depth of 3.43 µm using 1.0 µm particles and a 40× objective lens. This paper examines the performance of the present system, such as its ability to separate wavelengths. Furthermore, this system is applied to liquid–liquid two-phase flow, which consists of a water droplet and surrounding oil flow, in a microchannel. We succeeded in measuring each phase movement separately and simultaneously. As a result of the estimation of the out-of-plane velocity component, a three-dimensional flow structure is obtained and the interaction between each phase is investigated

  2. Procedure for measuring simultaneously the solar and visible properties of glazing with complex internal or external structures.

    Gentle, A R; Smith, G B

    2014-10-20

    Accurate solar and visual transmittances of materials in which surfaces or internal structures are complex are often not easily amenable to standard procedures with laboratory-based spectrophotometers and integrating spheres. Localized "hot spots" of intensity are common in such materials, so data on small samples is unreliable. A novel device and simple protocols have been developed and undergone validation testing. Simultaneous solar and visible transmittance and reflectance data have been acquired for skylight components and multilayer polycarbonate roof panels. The pyranometer and lux sensor setups also directly yield "light coolness" in lumens/watt. Sample areas must be large, and, although mainly in sheet form, some testing has been done on curved panels. The instrument, its operation, and the simple calculations used are described. Results on a subset of diffuse and partially diffuse materials with no hot spots have been cross checked using 150 mm integrating spheres with a spectrophotometer and the Air Mass 1.5 spectrum. Indications are that results are as good or better than with such spheres for transmittance, but reflectance techniques need refinement for some sample types.

  3. Measurement of the heat of smoldering combustion in straws and stalks by means of simultaneous thermal analysis

    He, Fang; Yi, Weiming; Zha, Jianwen [School of Light Industry and Agricultural Engineering, Shandong University of Technology, Zibo, Shandong 255049 (China)

    2009-01-15

    In order to investigate reaction heat of agro-stalks smoldering, wheat straw, corn stalk, cotton stalk, millet straw, sorghum stalk and sweet potato rattan powder were smoldered and pyrolyzed in a simultaneous thermal analyzer (STA). The samples were placed in a platinum crucible (5 mm x 5 mm) with a lid (with a 1 mm hole) on a high-accuracy differential scanning calorimetry-heat capacity (DSC-cp) holder in the furnace of an STA and heated from 303 to 1073 K at a heating rate of 10 K min{sup -1}. Sweeping gas with a flow rate of 25 ml min{sup -1} was air and nitrogen during smoldering and pyrolysis, respectively. Results showed that the heat emission characteristic of the smoldering process differed remarkably from the pyrolysis process. Based on the analysis of the DSC curves, oxidative polymer degradation heat and char oxidation heat were obtained from experimental data. It showed that the oxidative polymer degradation heat of the agro-stalks is more than 6.92 MJ kg{sup -1} consumed matter, higher than that of cellulose paper. And char oxidation heat is around 23 MJ kg{sup -1} consumed matter, similar to that of cellulose paper, but higher than that of cigarette. Total net heat emission of smoldering in STA was also obtained. These data can be used as reference data in analyzing smoldering of agro-stalks under similar conditions. (author)

  4. Simultaneous measurements of ion and electron currents using a novel compact electrostatic end-loss-current detector

    Hirata, M.; Miyake, Y.; Cho, T.; Kohagura, J.; Numakura, T.; Shimizu, K.; Ito, M.; Kiminami, S.; Morimoto, N.; Hirai, K.; Yamagishi, T.; Miyata, Y.; Nakashima, Y.; Miyoshi, S.; Ogura, K.; Kondoh, T.; Kariya, T.

    2006-10-01

    For the purpose of end-loss-ion and -electron analyses in open-field plasmas, a compact-sized electrostatic end-loss-current detector is proposed on the basis of a self-collection principle for suppressing the effects of secondary-electron emission from a metal collector. For employing this specific method, it is worth noting that no further additional magnetic systems except the ambient open-ended magnetic fields are required in the detector operation. This characteristic property provides a compactness of the total detection system and availability for its use in plasma confinement devices without disturbing plasma-confining magnetic fields. The detector consists of a set of parallel metal plates with respect to lines of ambient magnetic forces of a plasma device for analyzing incident ion currents along with a grid for shielding the collector against strays due to the metal-plate biasing. The characterization experiments are carried out by the use of a test-ion-beam line along with an additional use of a Helmholtz coil system for the formation of open magnetic fields similar to those in the GAMMA 10 end region. The applications of the developed end-loss-current detector in the GAMMA 10 plasma experiments are demonstrated under the conditions with simultaneous incidence of energetic electrons produced by electron-cyclotron heatings for end-loss-plugging potential formation.

  5. Simultaneous mesosphere-thermosphere-ionosphere parameter measurements over Gadanki (13.5°N, 79.2°E): First results

    Taori, A.; Dashora, N.; Raghunath, K.; Russell, J. M., III; Mlynczak, Martin G.

    2011-07-01

    We report first simultaneous airglow, lidar, and total electron content measurements in the mesosphere-thermosphere-ionosphere system behavior from Gadanki (13.5°N, 79.2°E). The observed variability in mesospheric temperatures and 630 nm thermospheric emission intensity shows large variations from one night to another with clear upward propagating waves at mesospheric altitudes. The deduced mesospheric temperatures compare well with Sounding of the Atmosphere Using Broadband Emission Radiometry (SABER)-derived temperatures, while the variability agrees well with lidar temperatures (on the night of simultaneous observations). The 630.0 nm thermospheric emission intensity and GPS-total electron content data exhibit occurrence of plasma depletions on the nights of 22-23 October and 22-23 May 2009, while no depletions are noted on the nearby nights of 23-24 October and 21-22 May 2009. These first simultaneous data reveal strong gravity-wave growth at upper mesospheric altitudes on the nights when plasma depletions were noted.

  6. Compact and portable open-path sensor for simultaneous measurements of atmospheric N2O and CO using a quantum cascade laser.

    Tao, Lei; Sun, Kang; Khan, M Amir; Miller, David J; Zondlo, Mark A

    2012-12-17

    A compact and portable open-path sensor for simultaneous detection of atmospheric N(2)O and CO has been developed with a 4.5 μm quantum cascade laser (QCL). An in-line acetylene (C(2)H(2)) gas reference cell allows for continuous monitoring of the sensor drift and calibration in rapidly changing field environments and thereby allows for open-path detection at high precision and stability. Wavelength modulation spectroscopy (WMS) is used to detect simultaneously both the second and fourth harmonic absorption spectra with an optimized dual modulation amplitude scheme. Multi-harmonic spectra containing atmospheric N(2)O, CO, and the reference C(2)H(2) signals are fit in real-time (10 Hz) by combining a software-based lock-in amplifier with a computationally fast numerical model for WMS. The sensor consumes ~50 W of power and has a mass of ~15 kg. Precision of 0.15 ppbv N(2)O and 0.36 ppbv CO at 10 Hz under laboratory conditions was demonstrated. The sensor has been deployed for extended periods in the field. Simultaneous N(2)O and CO measurements distinguished between natural and fossil fuel combustion sources of N(2)O, an important greenhouse gas with poorly quantified emissions in space and time.

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

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

    2017-01-13

    Wastewater treatment plants (WWTPs) emit CO 2 and N 2 O, which may lead to climate change and global warming. Over the last few years, awareness of greenhouse gas (GHG) emissions from WWTPs has increased. Moreover, the development of valid, reliable, and high-throughput analytical methods for simultaneous gas analysis is an essential requirement for environmental applications. In the present study, an analytical method based on a gas chromatograph (GC) equipped with a barrier ionization discharge (BID) detector was developed for the first time. This new method simultaneously analyses CO 2 and N 2 O and has a precision, measured in terms of relative standard of variation RSD%, equal to or less than 6.6% and 5.1%, respectively. The method's detection limits are 5.3ppm v for CO 2 and 62.0ppb v for N 2 O. The method's selectivity, linearity, accuracy, repeatability, intermediate precision, limit of detection and limit of quantification were good at trace concentration levels. After validation, the method was applied to a real case of N 2 O and CO 2 emissions from a WWTP, confirming its suitability as a standard procedure for simultaneous GHG analysis in environmental samples containing CO 2 levels less than 12,000mg/L. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Erratum: 'Double layer in an expanding plasma: Simultaneous upstream and downstream measurements' [Phys. Plasmas 15, 102113 (2008)

    Byhring, H. S.; Fredriksen, A.; Charles, C.; Boswell, R. W.

    2009-01-01

    As a result of the discovery of an error in the calibration of the simulated versus the measured magnetic field, a thorough mapping of the axial magnetic field has been carried out. The measurements show that the magnetic field is higher than what was believed to be the case, however, this does not affect the conclusions made in the article.

  9. Cross-field gradients: general concept, importance of multi-spacecraft measurements and study at 1 AU of the source intensity gradient for E > 30 keV solar event electrons

    P. A. Chaizy

    Full Text Available Three main physical processes (and associated properties are currently used to describe the flux and anisotropy time profiles of solar energetic par- ticle events, called SEP profiles. They are (1 the particle scattering (due to magnetic waves, (2 the particle focusing (due to the decrease of the amplitude of the interplanetary magnetic field (IMF with the radial distance to the Sun and (3 the finite injection profile at the source. If their features change from one field line to another, i.e. if there is a cross IMF gradient (CFG, then the shape of the SEP profiles will depend, at onset time, on the relative position of the spacecraft to the IMF and might vary significantly on small distance scale (e.g. 106 km. One type of CFG is studied here. It is called intensity CFG and considers variations, at the solar surface, only of the intensity of the event. It is shown here that drops of about two orders of magnitude over distances of ~104 km at the Sun (1° of angular distance can influence dramatically the SEP profiles at 1 AU. This CFG can lead to either an under or overestimation of both the parallel mean free path and of the injection parameters by factor up to, at least, ~2-3 and 18, respectively. Multi-spacecraft analysis can be used to identify CFG. Three basic requirements are proposed to identify, from the observation, the type of the CFG being measured.

    Key words: Solar physics, astrophysics, and astronomy (energetic particles; flares and mass ejections - Space plasma physics (transport processes

  10. Trace Contaminant Monitor for Air in Spacecraft, Phase I

    National Aeronautics and Space Administration — A need exists for analyzers that can measure trace contaminants in air on board spacecraft. Toxic gas buildup can endanger the crew particularly during long...

  11. Measuring the mutual effects between a CZT detector and MRI for the development of a simultaneous MBI/MRI insert

    Tao, Ashley [McMaster University (Canada); Farncombe, Troy [Hamilton Health Sciences (Canada); Noseworthy, Michael [McMaster University (Canada)

    2015-05-18

    While mammography is the gold standard for breast cancer screening, it suffers from poor sensitivity in women with dense breast tissue. Both breast MRI and molecular breast imaging (MBI) have been used as secondary imaging techniques. However, breast MRI suffers from low specificity and low sensitivity in MBI. A CZT based detector system has been developed with the goal of simultaneous MBI/MRI imaging to address the shortcomings of each modality. The performance of each modality needs to be addressed separately and together. The CZT system is comprised of four Redlen CZT modules tiled in a 2x2 array. Each module consists of 256 pixels and feature a builtin on-board ASIC and FPGA. A custom digital readout circuit board was designed to interface the four modules with a microcontroller to a PC. MR images were acquired with a 3T GE Discovery MR750 and Hologic breast coils. A gradient echo imaging sequence was used for all image acquisitions. A tissue mimicking phantom with a plastic grid insert (1 cm spacing) was used to evaluate geometric accuracy with the CZT detectors in the MRI bore. The average distance between the grid markers was 1Å 0.2cm indicating negligible geometric distortion. Field maps were generated with a uniform phantom to quantify the effect on magnetic field homogeneity. Early results indicate a significant distortion (~10ppm) in the magnetic field closest to the coil. Further analysis of the MR images will determine the extent of image quality degradation. A flood map of Tc-99m was acquired to evaluate and implement an energy correction map and a uniformity map. In the absence of a magnetic field, the mean energy resolution at 140keV was 6.3%. After fully characterizing the uniformity, geometric accuracy and sensitivity, the same metrics will be evaluated in the MRI bore.

  12. A Novel Triple-Pulsed 2-micrometer Lidar for Simultaneous and Independent CO2 and H2O Column Measurement

    Yu, Jirong; Singh, Upendra; Petros, Mulugeta; Refaat, Tamer

    2015-01-01

    The study of global warming needs precisely and accurately measuring greenhouse gases concentrations in the atmosphere. CO2 and H2O are important greenhouse gases that significantly contribute to the carbon cycle and global radiation budget on Earth. NRC Decadal Survey recommends a mission for Active Sensing of Carbon Dioxide (CO2) over Nights, Days and Seasons (ASCENDS). 2 micron laser is a viable IPDA transmitter to measure CO2 and H2O column density from space. The objective is to demonstrate a first airborne direct detection 2 micron IPDA lidar for CO2 and H2O measurements.

  13. Use of first-order diffraction wavelengths corresponding to dual-grating periodicities in a single fibre Bragg grating for simultaneous temperature and strain measurement

    Yam, Sui P; Brodzeli, Zourab; Rollinson, Claire M; Baxter, Greg W; Collins, Stephen F; Wade, Scott A

    2009-01-01

    A fibre Bragg grating (FBG) sensor, fabricated using a phase mask with 536 nm uniform pitch, for simultaneous temperature and strain measurement is presented. Two peaks/dips occur, at 785 and 1552 nm, due to reflection/transmission at the Bragg wavelength and at twice the Bragg wavelength, and arising primarily from FBG periodicities associated with half the phase mask periodicity and the phase mask periodicity, respectively. This grating was simple to fabricate and by having greater reflectivity at 785 nm, compared with 1552 nm, it is better suited for long-distance operation compared with similar schemes where the greater fibre attenuation at 785 nm is a significant limitation

  14. A novel approach for simultaneous measurements of Hall effect and magnetoresistance effect in solid and liquid state of gallium and mercury metals

    Ogita, M.; Nakao, M.; Singh, C.D.; Mogi, I.; Awaji, S.

    2004-01-01

    An AC-DC method has been proposed for simultaneous measurements of Hall effect and magnetoresistance effect in solid and liquid state of Ga and Hg metals. In low magnetic field Hall signal in solid state is proportional to magnetic field B, while in liquid state Hall signal is affected by magnetoresistance effect. It has been found that magnetoresistance has a B 2 dependence on magnetic field and affects the Hall signal. In high magnetic field, the Hall effect in liquid state is affected by a very large magnetoresistance effect compared in solid state. The magnetoresistance effect in liquid state is higher than solid state

  15. The purpose for GEO spacecraft deep charging and electrostatic discharging (ESD) experiment

    Yang Chuibai; Wang Shijin; Liang Jinbao

    2005-01-01

    This paper introduces the purpose for GEO spacecraft deep charging and electrostatic discharging (ESD) experiment. A method of experiment for the spacecraft deep charging and ESD aboard is proposed. Spacecraft deep charging and ESD event, frequency, energy and the level of pulse in wires due to EMP coupling into are measured. (authors)

  16. Development Of Protocols For Simultaneous Measurements Of Rn, Tn Using Nuclear Track Detectors And Trial Application In Mining Areas Of Vietnam

    Bui Dac Dung; Trinh Van Giap; Le Dinh Cuong; Tran Khanh Minh; Nguyen Huu Quyet; Nguyen Van Khanh; Tran Ngoc Toan

    2013-01-01

    Radioactive gases Radon (Rn) and Thoron (Tn) contribute of more than 50% of natural radiation dose. However, separate measurements of Rn and Tn have not been paid enough attention. An Intergovernmental Cooperation Project was conducted at the Institute for Nuclear Science and Technology with the help from Hungarian experts. The main tasks of the project were to finalize 02 protocols for simultaneous measurements of Rn and Tn using nuclear track detectors and to test these protocols in investigating the concentrations of Rn and Tn, calculating the natural dose due to Rn and Tn, and evaluating the increased radiation dose and radiation safety due to mining activities. Main results of the project include 02 protocols for simultaneous measurements of Rn and Tn and the test results in the mining areas. Rn and Tn concentrations inside the coal mining tunnels are in the average level of Vietnam and the world. Tn concentration inside the factory for separating Zircon at the Ha Tinh Zircon Processing Plant was found to be very high, up to 2931 Bq/m 3 . Based on annual effective dose calculation, workers inside the factory for separating Zircon at the Ha Tinh Zircon Processing Plant could receive an annual effective dose due to Rn and Tn of 4.890 mSv/year, and the increasing dose of 4.710 mSv/year is for higher than 1 mSv/year recommended by the IAEA. (author)

  17. An improved electrical sensor for simultaneous measurement of the void fraction and two phase flow velocity in the inclined pipe

    Won, Woo Yeon; Lee, Yeon Gun; Lee, Bo An; Koc, Min Seok; Kim, Sin

    2016-01-01

    The information for the flow pattern is also required to measure the void fraction. In order to solve this problems, Ko et al. proposed the void fraction measurement sensor according to the flow pattern using a three-electrode. The sensor system applied for a horizontal flow loop, and its measured performance for the void fraction was evaluated. In this study, a dual sensor was suggested to improve the measurement accuracy of the void fraction and the velocity. We applied the sensor to the inclined pipe simulating the PAFS heat exchanger. In order to verify the void fraction and velocity measurements, we used the wire-mesh sensor and the high-speed camera. In this study, an improved electrical conductance sensor for void fraction and velocity in inclined pipes has been designed. For minimizing between the sensor electrode interference, the numerical analysis has been performed. The loop experiments were conducted for several flow conditions and the experimental results for the void fractions and velocity measured by the proposed sensor were compared with those of a wiremesh sensor and high-speed camera.

  18. Simultaneous measurement of the maximum oscillation amplitude and the transient decay time constant of the QCM reveals stiffness changes of the adlayer.

    Marxer, C Galli; Coen, M Collaud; Bissig, H; Greber, U F; Schlapbach, L

    2003-10-01

    Interpretation of adsorption kinetics measured with a quartz crystal microbalance (QCM) can be difficult for adlayers undergoing modification of their mechanical properties. We have studied the behavior of the oscillation amplitude, A(0), and the decay time constant, tau, of quartz during adsorption of proteins and cells, by use of a home-made QCM. We are able to measure simultaneously the frequency, f, the dissipation factor, D, the maximum amplitude, A(0), and the transient decay time constant, tau, every 300 ms in liquid, gaseous, or vacuum environments. This analysis enables adsorption and modification of liquid/mass properties to be distinguished. Moreover the surface coverage and the stiffness of the adlayer can be estimated. These improvements promise to increase the appeal of QCM methodology for any applications measuring intimate contact of a dynamic material with a solid surface.

  19. Measuring arrangement for simultaneous and continuous determination of the total and radioactive amounts of reactive matters in flowing inert gases. Pt. 1

    Figge, K.; Martinen, H.; Schulz, W.

    1976-01-01

    In order to investigate the metabolism behaviour of radiocarbon-labelled substances, a special apparatus has been designed which enables a fully automatic as well as continuous and simultaneous determination of the total and the 14 C-labelled carbon dioxide (CO 2 ) in the respiratory air of small animals. The CO 2 which is exhaled by the experimental animals is absorbed quantitatively in a novel absorber-scintillator cocktail. The quantity of combined total CO 2 is then determined by measuring the specific conductivity whereas the amount of radioactive CO 2 is assessed via scintillation measurement. The measuring accuracy achieved is around 10 N cm 3 or about 5 nCi, whereas the CO 2 recovery is above 98%. In addition to the recording in a linear recorder, the data are transferred to punching tapes and can be evaluated in an EDP unit. (orig.) [de

  20. The Manned Spacecraft Center and medical technology

    Johnston, R. S.; Pool, S. L.

    1974-01-01

    A number of medically oriented research and hardware development programs in support of manned space flights have been sponsored by NASA. Blood pressure measuring systems for use in spacecraft are considered. In some cases, complete new bioinstrumentation systems were necessary to accomplish a specific physiological study. Plans for medical research during the Skylab program are discussed along with general questions regarding space-borne health service systems and details concerning the Health Services Support Control Center.

  1. Simultaneous optical and meteor head echo measurements using the Middle Atmosphere Alomar Radar System (MAARSY): Data collection and preliminary analysis

    Brown, P.; Stober, G.; Schult, C.; Krzeminski, Z.; Cooke, W.; Chau, J. L.

    2017-07-01

    The initial results of a two year simultaneous optical-radar meteor campaign are described. Analysis of 105 double-station optical meteors having plane of sky intersection angles greater than 5° and trail lengths in excess of 2 km also detected by the Middle Atmosphere Alomar Radar System (MAARSY) as head echoes was performed. These events show a median deviation in radiants between radar and optical determinations of 1.5°, with 1/3 of events having radiant agreement to less than one degree. MAARSY tends to record average speeds roughly 0.5 km/s and 1.3 km higher than optical records, in part due to the higher sensitivity of MAARSY as compared to the optical instruments. More than 98% of all head echoes are not detected with the optical system. Using this non-detection ratio and the known limiting sensitivity of the cameras, we estimate that the limiting meteoroid detection mass of MAARSY is in the 10-9-10-10 kg (astronomical limiting meteor magnitudes of +11 to +12) appropriate to speeds from 30 to 60 km/s. There is a clear trend of higher peak RCS for brighter meteors between 35 and -30 dBsm. For meteors with similar magnitudes, the MAARSY head echo radar cross-section is larger at higher speeds. Brighter meteors at fixed heights and similar speeds have consistently, on average, larger RCS values, in accordance with established scattering theory. However, our data show RCS ∝ v/2, much weaker than the normally assumed RCS ∝ v3, a consequence of our requiring head echoes to also be detectable optically. Most events show a smooth variation of RCS with height broadly following the light production behavior. A significant minority of meteors show large variations in RCS relative to the optical light curve over common height intervals, reflecting fragmentation or possibly differential ablation. No optically detected meteor occurring in the main radar beam and at times when the radar was collecting head echo data went unrecorded by MAARSY. Thus there does not

  2. Spacecraft Environmental Interactions Technology, 1983

    1985-01-01

    State of the art of environment interactions dealing with low-Earth-orbit plasmas; high-voltage systems; spacecraft charging; materials effects; and direction of future programs are contained in over 50 papers.

  3. Gravity Probe B spacecraft description

    Bennett, Norman R; Burns, Kevin; Katz, Russell; Kirschenbaum, Jon; Mason, Gary; Shehata, Shawky

    2015-01-01

    The Gravity Probe B spacecraft, developed, integrated, and tested by Lockheed Missiles and Space Company and later Lockheed Martin Corporation, consisted of structures, mechanisms, command and data handling, attitude and translation control, electrical power, thermal control, flight software, and communications. When integrated with the payload elements, the integrated system became the space vehicle. Key requirements shaping the design of the spacecraft were: (1) the tight mission timeline (17 months, 9 days of on-orbit operation), (2) precise attitude and translational control, (3) thermal protection of science hardware, (4) minimizing aerodynamic, magnetic, and eddy current effects, and (5) the need to provide a robust, low risk spacecraft. The spacecraft met all mission requirements, as demonstrated by dewar lifetime meeting specification, positive power and thermal margins, precision attitude control and drag-free performance, reliable communications, and the collection of more than 97% of the available science data. (paper)

  4. Simultaneous determination of nitric acid and uranium concentrations in aqueous solution from measurements of electrical conductivity, density, and temperature

    Spencer, B.B.

    1991-01-01

    Nuclear fuel reprocessing plants handle aqueous solutions of nitric acid and uranium in large quantities. Automatic control of process operations requires reliable measurements of these solutes concentration, but this is difficult to directly measure. Physical properties such as solution density and electrical conductivity vary with solute concentration and temperature. Conductivity, density and temperature can be measured accurately with relatively simple and inexpensive devices. These properties can be used to determine solute concentrations will good correlations. This paper provides the appropriate correlations for solutions containing 2 to 6 Molar (M) nitric acid and 0 to 300 g/L uranium metal at temperatures from 25--90 degrees C. The equations are most accurate below 5 M nitric acid, due to a broad maximum in the conductivity curve at 6 M. 12 refs., 9 figs., 6 tabs

  5. New methodological approaches to the simultaneous measurement of the 90Sr and 137Cs activity in environmental samples

    M. V. Zheltonozhska

    2012-12-01

    Full Text Available Nonradiochemical method of measurement of 90Sr and137Cs activity in environmental samples is proposed. This method is based on spectrometrical investigation of electrons accompanied the decay of the 90Sr and137Cs. Accounting for the contribution to the total activity of the samples from the zones with the density of the contamination 1 - 5 Кu/km2 the 40K electrons allowed to improve the accuracy of the measurements for the samples of small rodents up to 15 - 20 % (the ratio of A (137Cs/A (90Sr was from 2 to 100, for samples of soil up to 10 - 15 % (the change of activity in these samples was ten thousand times. The results of the spectrometric measurements were confirmed by the traditional radiochemical research.

  6. Simultaneous alcohol and cannabis expectancies predict simultaneous use

    Earleywine Mitch

    2006-10-01

    Full Text Available Abstract Background Simultaneous use of alcohol and cannabis predicts increased negative consequences for users beyond individual or even concurrent use of the two drugs. Given the widespread use of the drugs and common simultaneous consumption, problems unique to simultaneous use may bear important implications for many substance users. Cognitive expectancies offer a template for future drug use behavior based on previous drug experiences, accurately predicting future use and problems. Studies reveal similar mechanisms underlying both alcohol and cannabis expectancies, but little research examines simultaneous expectancies for alcohol and cannabis use. Whereas research has demonstrated unique outcomes associated with simultaneous alcohol and cannabis use, this study hypothesized that unique cognitive expectancies may underlie simultaneous alcohol and cannabis use. Results: This study examined a sample of 2600 (66% male; 34% female Internet survey respondents solicited through advertisements with online cannabis-related organizations. The study employed known measures of drug use and expectancies, as well as a new measure of simultaneous drug use expectancies. Expectancies for simultaneous use of alcohol and cannabis predicted simultaneous use over and above expectancies for each drug individually. Discussion Simultaneous expectancies may provide meaningful information not available with individual drug expectancies. These findings bear potential implications on the assessment and treatment of substance abuse problems, as well as researcher conceptualizations of drug expectancies. Policies directing the treatment of substance abuse and its funding ought to give unique consideration to simultaneous drug use and its cognitive underlying factors.

  7. A compact multi-plate fission chamber for the simultaneous measurement of 233U capture and fission cross-sections

    Bacak M.

    2017-01-01

    Full Text Available 233U plays the essential role of fissile nucleus in the Th-U fuel cycle. A particularity of 233U is its small neutron capture cross-section which is about one order of magnitude lower than the fission cross-section on average. Therefore, the accuracy in the measurement of the 233U capture cross-section essentially relies on efficient capture-fission discrimination thus a combined setup of fission and γ-detectors is needed. At CERN n_TOF the Total Absorption Calorimeter (TAC coupled with compact fission detectors is used. Previously used MicroMegas (MGAS detectors showed significant γ-background issues above 100 eV coming from the copper mesh. A new measurement campaign of the 233U capture cross-section and alpha ratio is planned at the CERN n_TOF facility. For this measurement, a novel cylindrical multi ionization cell chamber was developed in order to provide a compact solution for 14 active targets read out by 8 anodes. Due to the high specific activity of 233U fast timing properties are required and achieved with the use of customized electronics and the very fast ionizing gas CF4 together with a high electric field strength. This paper describes the new fission chamber and the results of the first tests with neutrons at GELINA proving that it is suitable for the 233U measurement.

  8. Simultaneous sound velocity and thickness measurement by the ultrasonic pitch-catch method for corrosion-layer-forming polymeric materials.

    Kusano, Masahiro; Takizawa, Shota; Sakai, Tetsuya; Arao, Yoshihiko; Kubouchi, Masatoshi

    2018-01-01

    Since thermosetting resins have excellent resistance to chemicals, fiber reinforced plastics composed of such resins and reinforcement fibers are widely used as construction materials for equipment in chemical plants. Such equipment is usually used for several decades under severe corrosive conditions so that failure due to degradation may result. One of the degradation behaviors in thermosetting resins under chemical solutions is "corrosion-layer-forming" degradation. In this type of degradation, surface resins in contact with a solution corrode, and some of them remain asa corrosion layer on the pristine part. It is difficult to precisely measure the thickness of the pristine part of such degradation type materials by conventional pulse-echo ultrasonic testing, because the sound velocity depends on the degree of corrosion of the polymeric material. In addition, the ultrasonic reflection interface between the pristine part and the corrosion layer is obscure. Thus, we propose a pitch-catch method using a pair of normal and angle probes to measure four parameters: the thicknesses of the pristine part and the corrosion layer, and their respective sound velocities. The validity of the proposed method was confirmed by measuring a two-layer sample and a sample including corroded parts. The results demonstrate that the pitch-catch method can successfully measure the four parameters and evaluate the residual thickness of the pristine part in the corrosion-layer-forming sample. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Simultaneous measurements of acetylene and soot during the pyrolysis of ethylene and benzene in a shock tube

    KC, Utsav; Beshir, Mohamed; Farooq, Aamir

    2016-01-01

    reflected shock waves at temperatures of 1600-2200. K and pressures of 3-5. bar. Acetylene mole fraction time-histories are measured from the absorption of a quantum-cascade laser operating around 13.6. μm. The soot volume fraction, particle size and number

  10. Carbon fluxes of surfaces vs. ecosystems. Advantages of measuring eddy covariance and soil respiration simultaneously in dry grassland ecosystems

    Nagy, Z.; Pintér, K.; Pavelka, Marian; Dařenová, Eva; Balogh, J.

    2011-01-01

    Roč. 8, č. 9 (2011), s. 2523-2534 ISSN 1726-4170 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Institutional research plan: CEZ:AV0Z60870520 Keywords : carbon fluxes * ecosystems * grassland ecoystems * measuring eddy covariance * soil respiration Subject RIV: EH - Ecology, Behaviour Impact factor: 3.859, year: 2011

  11. Vibration and Acoustic Testing for Mars Micromission Spacecraft

    Kern, Dennis L.; Scharton, Terry D.

    1999-01-01

    The objective of the Mars Micromission program being managed by the Jet Propulsion Laboratory (JPL) for NASA is to develop a common spacecraft that can carry telecommunications equipment and a variety of science payloads for exploration of Mars. The spacecraft will be capable of carrying robot landers and rovers, cameras, probes, balloons, gliders or aircraft, and telecommunications equipment to Mars at much lower cost than recent NASA Mars missions. The lightweight spacecraft (about 220 Kg mass) will be launched in a cooperative venture with CNES as a TWIN auxiliary payload on the Ariane 5 launch vehicle. Two or more Mars Micromission launches are planned for each Mars launch opportunity, which occur every 26 months. The Mars launch window for the first mission is November 1, 2002 through April 2003, which is planned to be a Mars airplane technology demonstration mission to coincide with the 100 year anniversary of the Kittyhawk flight. Several subsequent launches will create a telecommunications network orbiting Mars, which will provide for continuous communication with lenders and rovers on the Martian surface. Dedicated science payload flights to Mars are slated to start in 2005. This new cheaper and faster approach to Mars exploration calls for innovative approaches to the qualification of the Mars Micromission spacecraft for the Ariane 5 launch vibration and acoustic environments. JPL has in recent years implemented new approaches to spacecraft testing that may be effectively applied to the Mars Micromission. These include 1) force limited vibration testing, 2) combined loads, vibration and modal testing, and 3) direct acoustic testing. JPL has performed nearly 200 force limited vibration tests in the past 9 years; several of the tests were on spacecraft and large instruments, including the Cassini and Deep Space One spacecraft. Force limiting, which measures and limits the spacecraft base reaction force using triaxial force gages sandwiched between the

  12. Simultaneous measurements from the Millstone Hill radar and the Active satellite during the SAID/SAR arc event of the March 1990 CEDAR storm

    M. Förster

    Full Text Available During a nearby passage of the Active satellite above the Millstone Hill radar on 21 March 1990 at local sunset, the satellite and the radar performed simultaneous measurements of upper ionospheric parameters in nearly the same spatial volume. For this purpose the radar carried out a special azimuth-elevation scan to track the satellite. Direct comparisons of radar data and in situ satellite measurements have been carried out quite rarely. In this case, the coincidence of co-ordinated measurements and active ionospheric-magnetospheric processes during an extended storm recovery phase presents a unique occasion resulting in a very valuable data set. The measurements show generally good agreement both during quiet prestorm and storm conditions and the combination of radar and satellite observations gives a more comprehensive picture of the physical processes involved. We find a close relationship between the rapid westward ion drift peak at subauroral latitudes (SAID event and the occurrence of a stable auroral red (SAR arc observed after sunset by an all-sky imager and reported in an earlier study of this event. The SAID electric field is caused by the penetration of energetic ions with energies between about 1 keV and 100 keV into the outer plasmasphere to a latitude equatorward of the extent of the plasmasheet electrons. Charge separation results in the observed polarisation field and the SAID. Unusually high molecular ion densities measured by the satellite at altitudes of 700-870 km at subauroral and auroral latitudes point on strong upward-directed ion acceleration processes and an intense neutral gas upwelling. These structures are collocated with a narrow trough in electron density and an electron temperature peak as observed simultaneously by the radar and the satellite probes.

    Key words. Ionosphere (ionosphere-magnetosphere interactions; plasma temperature and density; Magnetospheric physics (plasmasphere.

  13. Multi-target retrieval (MTR): the simultaneous retrieval of pressure, temperature and volume mixing ratio profiles from limb-scanning atmospheric measurements

    Dinelli, B.M.; Alpaslan, D.; Carlotti, M.; Magnani, L.; Ridolfi, M.

    2004-01-01

    In this paper we describe a retrieval approach for the simultaneous determination of the altitude distributions of p, T and VMR of atmospheric constituents from limb-scanning measurements of the atmosphere. This analysis method, named multi-target retrieval (MTR), has been designed and implemented in a computer code aimed at the analysis of MIPAS-ENVISAT observations; however, the concepts implemented in MTR have a general validity and can be extended to the analysis of all type of limb-scanning observations. In order to assess performance and advantages of the proposed approach, MTR has been compared with the sequential analysis system implemented by ESA as the level-2 processor for MIPAS measurements. The comparison has been performed on a common set of target species and spectral intervals. The performed tests have shown that MTR produces results of better quality than a sequential retrieval. However, the simultaneous retrieval of p, T and water VMR has not lead to satisfactory results below the tropopause, because of the high correlation occurring between p and water VMR in the troposphere. We have shown that this problem can be fixed extending the MTR analysis to at least one further target whose spectral features decouple the retrieval of pressure and water VMR. Ozone was found to be a suitable target for this purpose. The advantages of the MTR analysis system in terms of systematic errors have also been discussed

  14. Simultaneous measurements of global vibrational spectra and dephasing times of molecular vibrational modes by broadband time-resolved coherent anti-Stokes Raman scattering spectrography

    Yin Jun; Yu Ling-Yao; Liu Xing; Wan Hui; Lin Zi-Yang; Niu Han-Ben

    2011-01-01

    In broadband coherent anti-Stokes Raman scattering (CARS) spectroscopy with supercontinuum (SC), the simultaneously detectable spectral coverage is limited by the spectral continuity and the simultaneity of various spectral components of SC in an enough bandwidth. By numerical simulations, the optimal experimental conditions for improving the SC are obtained. The broadband time-resolved CARS spectrography based on the SC with required temporal and spectral distributions is realised. The global molecular vibrational spectrum with well suppressed nonresonant background noise can be obtained in a single measurement. At the same time, the measurements of dephasing times of various molecular vibrational modes can be conveniently achieved from intensities of a sequence of time-resolved CARS signals. It will be more helpful to provide a complete picture of molecular vibrations, and to exhibit a potential to understand not only both the solvent dynamics and the solute-solvent interactions, but also the mechanisms of chemical reactions in the fields of biology, chemistry and material science. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  15. Prime mission results of the dual-frequency precipitation radar on the global precipitation measurement core spacecraft and the version 5 GPM standard products

    Furukawa, K.; Nio, T.; Oki, R.; Kubota, T.; Iguchi, T.

    2017-09-01

    The Dual-frequency Precipitation Radar (DPR) on the Global Precipitation Measurement (GPM) core satellite was developed by Japan Aerospace Exploration Agency (JAXA) and National Institute of Information and Communications Technology (NICT). The objective of the GPM mission is to observe global precipitation more frequently and accurately. The GPM core satellite is a joint product of National Aeronautics and Space Administration (NASA), JAXA and NICT. NASA developed the satellite bus and the GPM Microwave Imager (GMI), and JAXA and NICT developed the DPR. The inclination of the GPM core satellite is 65 degrees, and the nominal flight altitude is 407 km. The non-sunsynchronous circular orbit is necessary for measuring the diurnal change of rainfall. The DPR consists of two radars, which are Ku-band precipitation radar (KuPR) and Ka-band precipitation radar (KaPR). GPM core observatory was successfully launched by H2A launch vehicle on Feb. 28, 2014. DPR orbital check out was completed in May 2014. DPR products were released to the public on Sep. 2, 2014 and Normal Observation Operation period was started. JAXA is continuing DPR trend monitoring, calibration and validation operations to confirm that DPR keeps its function and performance on orbit. The results of DPR trend monitoring, calibration and validation show that DPR kept its function and performance on orbit during the 3 years and 2 months prime mission period. The DPR Prime mission period was completed in May 2017. The version 5 GPM products were released to the public in 2017. JAXA confirmed that GPM/DPR total system performance and the GPM version 5 products achieved the success criteria and the performance indicators that were defined for the JAXA GPM/DPR mission.

  16. Simultaneous measurement of 25 inflammatory markers and neurotrophins in neonatal dried blood spots by immunoassay with xMAP technology

    Skogstrand, Kristin; Thorsen, Poul; Nørgaard-Pedersen, Bent

    2005-01-01

    BACKGROUND: Inflammatory reactions and other events in early life may be part of the etiology of late-onset diseases, including cerebral palsy, autism, and type 1 diabetes. Most neonatal screening programs for congenital disorders are based on analysis of dried blood spot samples (DBSS), and stored...... on flowmetric Luminex xMAP technology to measure inflammatory markers and neutrophins in DBSS. RESULTS: The high-capacity 25-plex multianalyte method measured 23 inflammatory and trophic cytokines, triggering receptor expressed on myeloid cells-1 (TREM-1), and C-reactive protein in two 3.2-mm punches from DBSS...... potential for high-capacity analysis of DBSS in epidemiologic case-control studies and, with further refinements, in neonatal screening....

  17. Implementation of a Novel Laser System for Simultaneous Measurement of 13C/12C and D/H to Food Provenance

    Saad, N.; Hoffnagle, J.

    2012-04-01

    Olive oil samples were analyzed using the world's first simultaneous δ13C + δD instrument, the 13C+D Combustion Module-Cavity Ringdown Spectroscopy (CM-CRDS) Isotope Analyzer. Simultaneous measurements of δ13C and δD of the whole oil have been performed on commercially available olive oils produced in Greece, Spain, Italy, California, Lebanon, Israel, Australia and Turkey. Together, the measurements of isotopic ratios of carbon (13C/12C) and hydrogen (D/H) produce statistically significant differentiation between olive oils from different locations around the globe. Stable isotope ratios are exquisitely sensitive to the biochemistry of plant species and the nutrients available to them in a particular geographical location. Isotope ratios provide detailed knowledge useful for forensic applications through a combination of stable-isotope measurements of carbon (13C/12C) and hydrogen (D/H) isotopes of organic matter and can help the associations among specific geographic areas through the measurement of these dual isotopes. We report here on the development of a novel laser spectroscopy based system for the simultaneous analysis of the stable isotope ratios of carbon (13C/12C) and hydrogen (D/H) that is robust, easy-to-use, and is the first stable isotope ratio analysis system to combine the measurement of 13C/12C and D/H in one simple analysis from a bulk organic sample. The system comprises a combustion module to convert the organic sample into CO2 and H2O and a Cavity Ring-Down Spectrometer (CRDS) that analyzes the combustion species inside an optical cavity based on the molecular absorption of individual isotopomers. The CRDS uses dual lasers to target the four isotpomers of interest: 12CO2, 13CO2, H2O and HDO. The system delivers a typical precision of 0.1permil for δ13C and 1.5 permil for δD that parallels that achieved by IRMS, but with an unprecedented simplicity that allows scientists to leverage the science and map out the provenance of the analyzed

  18. Simultaneous remote measurement of CO2 concentration, humidity and temperature with a matrix of optical fiber sensors

    Wysokiński, Karol; Filipowicz, Marta; Stańczyk, Tomasz; Lipiński, Stanisław; Napierała, Marek; Murawski, Michał; Nasiłowski, Tomasz

    2017-10-01

    A matrix of optical fiber sensors eligible for remote measurements is reported in this paper. The aim of work was to monitor the air quality with a device, which does not need any electricity on site of the measurement. The matrix consists of several sensors detecting carbon dioxide concentration, relative humidity and temperature. Sensors utilize active optical materials, which change their color when exposed to varied conditions. All the sensors are powered with standard light emitting diodes. Light is transmitted by an optical fiber from the light source and then it reaches the active layer which changes its color, when the conditions change. This results in a change of attenuation of light passing through the active layer. Modified light is then transmitted by another optical fiber to the detector, where simple photoresistor is used. It is powered by a stabilized DC power supply and the current is measured. Since no expensive elements are needed to manufacture such a matrix of sensors, its price may be competitive to the price of the devices already available on the market, while the matrix also exhibits other valuable properties.

  19. Cometary dust size distributions from flyby spacecraft

    Divine, N.

    1988-01-01

    Pior to the Halley flybys in 1986, the distribution of cometary dust grains with particle size were approximated using models which provided reasonable fits to the dynamics of dust tails, anti-tails, and infrared spectra. These distributions have since been improved using fluence data (i.e., particle fluxes integrated over time along the flyby trajectory) from three spacecraft. The fluence derived distributions are appropriate for comparison with simultaneous infrared photometry (from Earth) because they sample the particles in the same way as the IR data do (along the line of sight) and because they are directly proportional to the concentration distribution in that region of the coma which dominates the IR emission

  20. New methodology for simultaneous volumetric and calorimetric measurements: Direct determination of {alpha}{sub p} and C{sub p} for liquids under pressure

    Casas, L. M. [Departamento de Fisica Aplicada, Facultad de Ciencias Experimentales, Universidad de Vigo, Lagoas Marcosende s/n, 36310 Vigo (Spain); Plantier, F.; Bessieres, D. [Laboratoire de Thermodynamique et Energetique des Fluides Complexes-UMR 5150, Universite de Pau et des Pays de l' Adour, BP 1155, 64013 Pau (France)

    2009-12-15

    A new batch cell has been developed to measure simultaneously both isobaric thermal expansion and isobaric heat capacity from calorimetric measurements. The isobaric thermal expansion is directly proportional to the linear displacement of an inner flexible below and the heat capacity is calculated from the calorimetric signal. The apparatus used was a commercial Setaram C-80 calorimeter and together with this type of vessels can be operated up to 20 MPa and in the temperature range of 303.15-523.15 K, In this work, calibration was carried out using 1-hexanol and subsequently both thermophysical properties were determined for 3-pentanol, 3-ethyl-3-pentanol, and 1-octanol at atmospheric pressure, 5 and 10 MPa, and from 303.15 to 423.15 K in temperature. Finally experimental values were compared with the literature in order to validate this new methodology, which allows a very accurate determination of isobaric thermal expansion and isobaric heat capacity.

  1. Simultaneous measure of a spectral line profile and the apparatus function of a Fabry-Perot spectrometer when continuous background is present

    Moreno, J.M.; Quintanilla, M.; Mar, S.

    1978-01-01

    A deconvolution method of registered profile on a Fabry-Perot spectrometer is developed, when the actual profile of the source is a Voigt pattern together with a continuous background. The reliability and accuracy of the method is tested with theoreticaly simulated profiles. The method is applied both to measure the real line profiles and to find the Fabry-Perot parameters, as a test of its validity on studies of experimental profiles. Both measure types -source profile and apparatus function- are made simultaneously by means of analysis of the variations of registered profile, at 6438.5A Cd line and 6328A He-Ne laser line, varying the optical path between interferometer mirrors. (author) [es

  2. Study of charge symmetry in 4He by simultaneous 4He(e,e'p)3H and 4He(e,e'n)3He measurements

    Spahn, M.; Kihm, T.; Knopfle, K.T.; Friedrich, J.; Voegler, N.; Schmitt, C.; Walther, V.H.; Unkelbach, M.; Hofmann, H.M.

    1989-01-01

    We have measured the ( 3 H+p) and ( 3 He+n) breakup of 4 He by 4 He(e,e'c) coincidence experiments at low momentum transfer (q∼0.39 fm -1 ) in the excitation energy region 22≤E x ≤36 MeV. Both channels were studied simultaneously by detecting the charged fragments c=p, 3 H, and 3 He in the same detector system. The measured 4 He(e,e'p) 3 H and 4 He(e,e'n) 3 He angular correlations as well as the deduced total 4 He(e,e'p) 3 H and 4 He(e,e'n) 3 He cross sections are reproduced by microscopic model calculations with a charge-symmetric nuclear Hamiltonian

  3. Neutron interrogation of actinides with a 17 MeV electron accelerator and first results from photon and neutron interrogation non-simultaneous measurements combination

    Sari, A., E-mail: adrien.sari@cea.fr [CEA, LIST, Laboratoire Capteurs et Architectures Electroniques, 91191 Gif-sur-Yvette Cedex (France); Carrel, F.; Lainé, F. [CEA, LIST, Laboratoire Capteurs et Architectures Electroniques, 91191 Gif-sur-Yvette Cedex (France); Lyoussi, A. [CEA, DEN, 13108 Saint-Paul-Lez-Durance Cedex (France)

    2013-10-01

    In this article, we demonstrate the feasibility of neutron interrogation using the conversion target of a 17 MeV linear electron accelerator as a neutron generator. Signals from prompt neutrons, delayed neutrons, and delayed gamma-rays, emitted by both uranium and plutonium samples were analyzed. First results from photon and neutron interrogation non-simultaneous measurements combination are also reported in this paper. Feasibility of this technique is shown in the frame of the measurement of uranium enrichment. The latter was carried out by combining detection of prompt neutrons from thermal fission and delayed neutrons from photofission, and by combining delayed gamma-rays from thermal fission and delayed gamma-rays from photofission.

  4. Accurate atom-solid kinetic energy shifts from the simultaneous measurement of the KLL Auger spectra for Na, Mg, Al and Si

    Aksela, S; Turunen, P; Kantia, T; Aksela, H

    2011-01-01

    KLL Auger-energy shifts between free atoms and their solid surfaces were determined from spectra measured simultaneously in identical experimental conditions. Essentially, the shift values obtained for Na, Mg, Al and Si were more accurate than those achieved by combining the results from separate vapour and solid measurements. Using atomic Auger energies and determined shifts, reliable absolute solid state Auger energies with respect to the vacuum level were also obtained. Experimental shift values were also compared with calculations obtained with the excited atom model. 2s and 2p binding energy shifts were estimated from recent high resolution and due to open shell strongly split vapour phase spectra and corresponding published solid state results. Also, the question of the extent to which the 2s and 2p shifts deviate has been discussed here. (paper)

  5. Simultaneous measurement of thermal conductivity, thermal diffusivity and prediction of effective thermal conductivity of porous consolidated igneous rocks at room temperature

    Aurangzeb; Ali, Zulqurnain; Gurmani, Samia Faiz; Maqsood, Asghari

    2006-01-01

    Thermal conductivity, thermal diffusivity and heat capacity per unit volume of porous consolidated igneous rocks have been measured, simultaneously by Gustafsson's probe at room temperature and normal pressure using air as saturant. Data are presented for eleven samples of dunite, ranging in porosity from 0.130 to 0.665% by volume, taken from Chillas near Gilgit, Pakistan. The porosity and density parameters have been measured using American Society of Testing and Materials (ASTM) standards at ambient conditions. The mineral composition of samples has been analysed from their thin sections (petrography). An empirical model to predict the thermal conductivity of porous consolidated igneous rocks is also proposed. The thermal conductivities are predicted by some of the existing models along with the proposed one. It is observed that the values of effective thermal conductivity predicted by the proposed model are in agreement with the experimental thermal conductivity data within 6%

  6. Spacecraft charging and related effects during Halley encounter

    Young, D.T.

    1983-01-01

    Hypervelocity (69 km/s) impact of cometary material with surfaces of the GIOTTO spacecraft will induce a number of spurious and possibly harmful phenomena. The most serious of these is likely to be spacecraft charging that results from impact-produced plasma distributions surrounding GIOTTO. The ESA Plasma Environment Working Group, whose studies are the basis for this report, finds that charging may become significant within approx. 10 5 km of the nucleus where potentials of approx. = +20 V are to be expected. In addition to spacecraft charging, impact produced plasma may interfere with in situ plasma measurements, particularly those of ion plasma analyzers and mass spectrometers

  7. Four-spacecraft determination of magnetopause orientation, motion and thickness: comparison with results from single-spacecraft methods

    S. E. Haaland

    2004-04-01

    Full Text Available In this paper, we use Cluster data from one magnetopause event on 5 July 2001 to compare predictions from various methods for determination of the velocity, orientation, and thickness of the magnetopause current layer. We employ established as well as new multi-spacecraft techniques, in which time differences between the crossings by the four spacecraft, along with the duration of each crossing, are used to calculate magnetopause speed, normal vector, and width. The timing is based on data from either the Cluster Magnetic Field Experiment (FGM or the Electric Field Experiment (EFW instruments. The multi-spacecraft results are compared with those derived from various single-spacecraft techniques, including minimum-variance analysis of the magnetic field and deHoffmann-Teller, as well as Minimum-Faraday-Residue analysis of plasma velocities and magnetic fields measured during the crossings. In order to improve the overall consistency between multi- and single-spacecraft results, we have also explored the use of hybrid techniques, in which timing information from the four spacecraft is combined with certain limited results from single-spacecraft methods, the remaining results being left for consistency checks. The results show good agreement between magnetopause orientations derived from appropriately chosen single-spacecraft techniques and those obtained from multi-spacecraft timing. The agreement between magnetopause speeds derived from single- and multi-spacecraft methods is quantitatively somewhat less good but it is evident that the speed can change substantially from one crossing to the next within an event. The magnetopause thickness varied substantially from one crossing to the next, within an event. It ranged from 5 to 10 ion gyroradii. The density profile was sharper than the magnetic profile: most of the density change occured in the earthward half of the magnetopause.

    Key words. Magnetospheric physics (magnetopause, cusp and

  8. Simultaneous state-parameter estimation supports the evaluation of data assimilation performance and measurement design for soil-water-atmosphere-plant system

    Hu, Shun; Shi, Liangsheng; Zha, Yuanyuan; Williams, Mathew; Lin, Lin

    2017-12-01

    Improvements to agricultural water and crop managements require detailed information on crop and soil states, and their evolution. Data assimilation provides an attractive way of obtaining these information by integrating measurements with model in a sequential manner. However, data assimilation for soil-water-atmosphere-plant (SWAP) system is still lack of comprehensive exploration due to a large number of variables and parameters in the system. In this study, simultaneous state-parameter estimation using ensemble Kalman filter (EnKF) was employed to evaluate the data assimilation performance and provide advice on measurement design for SWAP system. The results demonstrated that a proper selection of state vector is critical to effective data assimilation. Especially, updating the development stage was able to avoid the negative effect of ;phenological shift;, which was caused by the contrasted phenological stage in different ensemble members. Simultaneous state-parameter estimation (SSPE) assimilation strategy outperformed updating-state-only (USO) assimilation strategy because of its ability to alleviate the inconsistency between model variables and parameters. However, the performance of SSPE assimilation strategy could deteriorate with an increasing number of uncertain parameters as a result of soil stratification and limited knowledge on crop parameters. In addition to the most easily available surface soil moisture (SSM) and leaf area index (LAI) measurements, deep soil moisture, grain yield or other auxiliary data were required to provide sufficient constraints on parameter estimation and to assure the data assimilation performance. This study provides an insight into the response of soil moisture and grain yield to data assimilation in SWAP system and is helpful for soil moisture movement and crop growth modeling and measurement design in practice.

  9. A three-color absorption/scattering imaging technique for simultaneous measurements on distributions of temperature and fuel concentration in a spray

    Qi, Wenyuan; Zhang, Yuyin

    2018-04-01

    A three-color imaging technique was proposed for simultaneous measurements on distributions of fuel/air mixture temperature and fuel vapor/liquid concentrations in evaporating sprays. The idea is based on that the vapor concentration is proportional to the absorption of vapor to UV light, the liquid-phase concentration is related to the light extinction due to scattering of droplet to visible light, and the mixture temperature can be correlated to the absorbance ratio at two absorbing wavelengths or narrow bands. For verifying the imaging system, the molar absorption coefficients of p-xylene at the three narrow bands, which were centered respectively at 265, 289, and 532 nm with FWHM of 10 nm, were measured in a specially designed calibration chamber at different temperatures (423-606 K) and pressure of 3.6 bar. It was found that the ratio of the molar absorption coefficients of p-xylene at the two narrow bands centered at the two UV wavelengths is sensitive to the mixture temperature. On the other hand, the distributions of fuel vapor/liquid concentrations can be obtained by use of absorbance due to ultraviolet absorption of vapor and visible light scattering of droplets. Combining these two methods, a simultaneous measurement on distributions of mixture temperature and fuel vapor/liquid concentrations can be realized. In addition, the temperature field obtained from the ratio of the two absorbing narrow bands can be further used to improve the measurement accuracy of vapor/liquid concentrations, because the absorption coefficients depend on temperature. This diagnostic was applied to an evaporating spray inside a high-temperature and high-pressure constant volume chamber.

  10. TH-CD-201-03: A Real-Time Method to Simultaneously Measure Linear Energy Transfer and Dose for Proton Therapy Using Organic Scintillators

    Alsanea, F; Therriault-Proulx, F; Sawakuchi, G; Beddar, S [UT MD Anderson Cancer Center, Houston, TX (United States)

    2016-06-15

    Purpose: The light generated in organic scintillators depends on both the radiation dose and the linear energy transfer (LET). The LET dependence leads to an under-response of the detector in the Bragg peak of proton beams. This phenomenon, called ionization quenching, must be corrected to obtain accurate dose measurements of proton beams. This work exploits the ionization quenching phenomenon to provide a method of measuring LET and auto correcting quenching. Methods: We exposed simultaneously four different organic scintillators (BCF-12, PMMA, PVT, and LSD; 1mm in diameter) and a plane parallel ionization chamber in passively scattered proton beams to doses between 32 and 43 cGy and fluence averaged LET values from 0.47 to 1.26 keV/µm. The LET values for each irradiation condition were determined using a validated Monte Carlo model of the beam line. We determined the quenching parameter in the Birk’s equation for scintillation in BCF-12 for dose measurements. One set of irradiation conditions was used to correlate the scintillation response ratio to the LET values and plot a scintillation response ratio versus LET calibration curve. Irradiation conditions independent from the calibration ones were used to validate this method. Comparisons to the expected values were made on both the basis of dose and LET. Results: Among all the scintillators investigated, the ratio of PMMA to BCF-12 provided the best correlation to LET values and was used as the LET calibration curve. The expected LET values in the validation set were within 2%±6%, which resulted in dose accuracy of 1.5%±5.8% for the range of LET values investigated in this work. Conclusion: We have demonstrated the feasibility of using the ratio between the light output of two organic scintillators to simultaneously measure LET and dose of therapeutic proton beams. Further studies are needed to verify the response in higher LET values.

  11. Simultaneous measurement of top quark mass and jet energy scale using template fits at the CMS experiment

    Naumann-Emme, Sebastian

    2011-07-15

    In this thesis, pairs of top quarks produced in proton-proton collisions at a center-of-mass energy of 7 TeV and decaying in the muon+jets channel t anti t {yields} (b{mu}{nu})(bqq{sup '}) are analyzed using data that were recorded by the CMS detector in the year 2010 and correspond to an integrated luminosity of 35.9 pb{sup -1}. A sample of 78 events is selected by requiring exactly one isolated muon and at least four jets, two of them being identified as jets from the decay of b quarks. Given these selection criteria, the expected fraction of t anti t events is 94%. The trijet mass, M3, and the dijet mass, M2, are reconstructed, taking into account the b-tagging information. M3 and M2 are estimators of the masses of hadronically decaying top quarks and the corresponding W bosons, respectively. Templates for M2 and for the event-wise mass difference {delta}M{sub 32}=M3-M2 are parametrized as linear functions of the top quark mass, m{sub t}, and the jet energy scale (JES). Based on the precise knowledge of the W boson mass, M2 provides a strong handle on the energy scale of jets from light quarks. The reconstructed M2 and {delta}M{sub 32} in data are compared to the template functions from simulation in a combined likelihood fit. The overall JES in the selected sample is found to be 1.048{+-}0.040(stat){+-}0.015(syst) relative to the simulated JES and the measured m{sub t} is 167.8{+-}7.1(stat+JES){+-}3.1(syst) GeV. This is one of the first measurements of m{sub t} at the Large Hadron Collider. Furthermore, the JES measurement is an important input for the commissioning of the CMS experiment for the upcoming measurements with more data in the near future. (orig.)

  12. Simultaneous measurement of static and kinetic friction of ZnO nanowires in situ with a scanning electron microscope.

    Polyakov, Boris; Dorogin, Leonid M; Vlassov, Sergei; Kink, Ilmar; Romanov, Alexey E; Lohmus, Rynno

    2012-11-01

    A novel method for in situ measurement of the static and kinetic friction is developed and demonstrated for zinc oxide nanowires (NWs) on oxidised silicon wafers. The experiments are performed inside a scanning electron microscope (SEM) equipped with a nanomanipulator with an atomic force microscope tip as a probe. NWs are pushed by the tip from one end until complete displacement is achieved, while NW bending is monitored by the SEM. The elastic bending profile of a NW during the manipulation process is used to calculate the static and kinetic friction forces. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. The continuous monitoring of the artificial beta aerosol activity by measuring the alpha and beta activity in aerosol simultaneously

    Hayakawa, Hironobu; Oonishi, Masaki; Matsuura, Hiroyuki

    1990-01-01

    We have constructed the system to monitor the artificial beta aerosol activity around the nuclear power plants continuously in real time. The smaller releases of artificial radionuclides from the nuclear power plants can be lost in the fluctuations of the natural background of the beta aerosol activity, when only the beta activity of the aerosol is measured. This method to discriminate the artificial and the natural beta activity of the aerosol is based on the fact that the ratio of the natural alpha and beta activities of the aerosol is almost constant. The detection limit of this system is below 3 Bq/m 3 . (author)

  14. Simultaneous measurement of top quark mass and jet energy scale using template fits at the CMS experiment

    Naumann-Emme, Sebastian

    2011-07-01

    In this thesis, pairs of top quarks produced in proton-proton collisions at a center-of-mass energy of 7 TeV and decaying in the muon+jets channel t anti t → (bμν)(bqq ' ) are analyzed using data that were recorded by the CMS detector in the year 2010 and correspond to an integrated luminosity of 35.9 pb -1 . A sample of 78 events is selected by requiring exactly one isolated muon and at least four jets, two of them being identified as jets from the decay of b quarks. Given these selection criteria, the expected fraction of t anti t events is 94%. The trijet mass, M3, and the dijet mass, M2, are reconstructed, taking into account the b-tagging information. M3 and M2 are estimators of the masses of hadronically decaying top quarks and the corresponding W bosons, respectively. Templates for M2 and for the event-wise mass difference ΔM 32 =M3-M2 are parametrized as linear functions of the top quark mass, m t , and the jet energy scale (JES). Based on the precise knowledge of the W boson mass, M2 provides a strong handle on the energy scale of jets from light quarks. The reconstructed M2 and ΔM 32 in data are compared to the template functions from simulation in a combined likelihood fit. The overall JES in the selected sample is found to be 1.048±0.040(stat)±0.015(syst) relative to the simulated JES and the measured m t is 167.8±7.1(stat+JES)±3.1(syst) GeV. This is one of the first measurements of m t at the Large Hadron Collider. Furthermore, the JES measurement is an important input for the commissioning of the CMS experiment for the upcoming measurements with more data in the near future. (orig.)

  15. MIDN: A spacecraft Micro-dosimeter mission

    Pisacane, V. L.; Ziegler, J. F.; Nelson, M. E.; Caylor, M.; Flake, D.; Heyen, L.; Youngborg, E.; Rosenfeld, A. B.; Cucinotta, F.; Zaider, M.; Dicello, J. F.

    2006-01-01

    MIDN (Micro-dosimetry instrument) is a payload on the MidSTAR-I spacecraft (Midshipman Space Technology Applications Research) under development at the United States Naval Academy. MIDN is a solid-state system being designed and constructed to measure Micro-dosimetric spectra to determine radiation quality factors for space environments. Radiation is a critical threat to the health of astronauts and to the success of missions in low-Earth orbit and space exploration. The system will consist of three separate sensors, one external to the spacecraft, one internal and one embedded in polyethylene. Design goals are mass <3 kg and power <2 W. The MidSTAR-I mission in 2006 will provide an opportunity to evaluate a preliminary version of this system. Its low power and mass makes it useful for the International Space Station and manned and unmanned interplanetary missions as a real-time system to assess and alert astronauts to enhanced radiation environments. (authors)

  16. Evaluation of Ultrafiltration for Spacecraft Water Reuse

    Pickering, Karen D.; Wiesner, Mark R.

    2001-01-01

    Ultrafiltration is examined for use as the first stage of a primary treatment process for spacecraft wastewater. It is hypothesized that ultrafiltration can effectively serve as pretreatment for a reverse osmosis system, removing the majority of organic material in a spacecraft wastewater. However, it is believed that the interaction between the membrane material and the surfactant found in the wastewater will have a significant impact on the fouling of the ultrafiltration membrane. In this study, five different ultrafiltration membrane materials are examined for the filtration of wastewater typical of that expected to be produced onboard the International Space Station. Membranes are used in an unstirred batch cell. Flux, organic carbon rejection, and recovery from fouling are measured. The results of this evaluation will be used to select the most promising membranes for further study.

  17. Probing interferometric parallax with interplanetary spacecraft

    Rodeghiero, G.; Gini, F.; Marchili, N.; Jain, P.; Ralston, J. P.; Dallacasa, D.; Naletto, G.; Possenti, A.; Barbieri, C.; Franceschini, A.; Zampieri, L.

    2017-07-01

    We describe an experimental scenario for testing a novel method to measure distance and proper motion of astronomical sources. The method is based on multi-epoch observations of amplitude or intensity correlations between separate receiving systems. This technique is called Interferometric Parallax, and efficiently exploits phase information that has traditionally been overlooked. The test case we discuss combines amplitude correlations of signals from deep space interplanetary spacecraft with those from distant galactic and extragalactic radio sources with the goal of estimating the interplanetary spacecraft distance. Interferometric parallax relies on the detection of wavefront curvature effects in signals collected by pairs of separate receiving systems. The method shows promising potentialities over current techniques when the target is unresolved from the background reference sources. Developments in this field might lead to the construction of an independent, geometrical cosmic distance ladder using a dedicated project and future generation instruments. We present a conceptual overview supported by numerical estimates of its performances applied to a spacecraft orbiting the Solar System. Simulations support the feasibility of measurements with a simple and time-saving observational scheme using current facilities.

  18. Simultaneous measurements of disk vibration and pressure fluctuation in turbulent flow developing in a model hard disk drive

    Kurashima, D.; Naka, Y.; Fukagata, K. [Department of Mechanical Engineering, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan); Obi, S., E-mail: obsn@mech.keio.ac.jp [Department of Mechanical Engineering, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan)

    2011-06-15

    The complex flow features inside hard disk drive models are investigated in an axisymmetric and a semi-open shroud configurations. For the axisymmetric case, we have employed both experimental and computational approaches. The experiment focuses on both flow dynamics and the disk vibration, where measurements of the fluctuating pressure and velocity are undertaken at some representative points. The correlation between the disk vibration and the fluctuating pressure in the turbulent flow between disks is evident from the spectral analysis. The experimentally observed fluctuating pressure and velocity are partly due to the disk vibration and its contribution could be estimated by comparing the experiment with the results of a large eddy simulation. For the semi-open shroud case, although the characteristic peaks attributable to the large-scale vortical structure are still observed in the power spectra, the pressure fluctuation and the disk vibration are suppressed when the arm is inserted.

  19. Simultaneous measurement of proline and related compounds in oak leaves by high-performance ligand-exchange chromatography and electrospray ionization mass spectrometry for environmental stress studies.

    Oufir, Mouhssin; Schulz, Nadine; Sha Vallikhan, Patan Shaik; Wilhelm, Eva; Burg, Kornel; Hausman, Jean-Francois; Hoffmann, Lucien; Guignard, Cedric

    2009-02-13

    A mass spectrometer was coupled to high-performance ligand-exchange liquid chromatography (HPLEC) for simultaneous analysis of stress associated solutes such as proline, hydroxyproline, methylproline, glycine betaine and trigonelline extracted from leaves of drought stressed oaks and an internal standard namely N-acetylproline. Methanol/chloroform/water extracts were analyzed using an Aminex HPX-87C column and specifically quantified by the positive ion mode of an electrospray ionisation-mass spectrometry (ESI-MS) in single ion monitoring (SIM) mode. The recovery of N-acetyl proline added to oak leaf extracts ranged from 85.2 to 122.1% for an intra-day study. Standard calibration curves showed good linearity in the measured range from 0.3125 to 10micromolL(-1) with the lowest correlation coefficient of 0.99961 for trigonelline. The advantages of this alternative procedure, compared to previously published methods using fluorescence or amperometric detections, are the simultaneous and direct detection of osmoprotectants in a single chromatographic run, a minimal sample preparation, a good specificity and reduced limits of quantification, ranging from 0.1 to 0.6micromolL(-1). Fifty-six days of water deficit exposure resulted in increased foliar free proline levels (2.4-fold, P<0.001, 155micromolg(-1) FW) and glycine betaine contents (2.5-fold, P<0.05, 175micromolg(-1) FW) of drought stressed oak compared to control.

  20. A simultaneous measurement of the b-tagging efficiency scale factor and the t(bar t) Production Cross Section at the Collider Detector at Fermilab

    Hussain, Nazim

    2011-01-01

    The ability to compare results between Monte Carlo and data is imperative in modern experimental high-energy physics analyses. The b-tagging efficiency Scale Factor (SF) allows for an accurate comparison of b quark identification in data samples and Monte Carlo. This thesis presents a simultaneous measurement of the SF for the SecVtx algorithm and the t(bar t) production cross section using 5.6 fb -1 of p(bar p) collision data at √s = 1.96 TeV collected by the Collider Detector at Fermilab (CDF) experiment. The t(bar t) cross section was measured to be 7.26 ± 0.47 pb, consistent with prior CDF analyses. The tight SF value was measured to be 0.925 ± 0.032 and the loose SF value was measured at 0.967 ± 0.033. These are the most precise SF SecVtx measurements to be performed at CDF to date.

  1. Single-experiment simultaneous-measurement of elemental mass-attenuation coefficients of hydrogen, carbon and oxygen for 0.123-1.33 MeV gamma rays

    Teli, M.T.; Nathuram, R.; Mahajan, C.S.

    2000-01-01

    As it is inconvenient to use elements like hydrogen, carbon and oxygen in pure forms for measurement of their gamma mass-attenuation coefficients, the measurements are to be done indirectly, by using compounds of the elements or a mixture of them. We give here a simple method of measuring the total mass-attenuation coefficients μ/ρ of the elements in a compound simultaneously and in a single experiment through the measurements of the μ/ρ values of the concerned compounds and using the mixture rule. The method is applied for the measurement of μ/ρ of hydrogen, carbon and oxygen by using acetone, ethanol and 1-propanol. Our results (for E γ =0.123-1.33 MeV) are seen to be in better agreement with the theoretical values of Hubbell and Seltzer (1995) [Hubbell J.H. and Seltzer S.M. (1995). Tables of X-ray mass attenuation coefficients and mass energy-absorption coefficients 1 keV to 20 MeV for elements Z=1 to 92 and 48 additional substances of dosimetric interest. NISTIR 5632] as compared to the results of El-Kateb and Abdul-Hamid (1991) [El-Kateb, A.H., Abdul-Hamid, A.S., 1991. Photon attenuation coefficient study of some materials containing hydrogen, carbon, and oxygen. Appl. Rad. Isot. 42, 303-307

  2. Proposal of AAA-battery-size one-shot ATR Fourier spectroscopic imager for on-site analysis: Simultaneous measurement of multi-components with high accuracy

    Hosono, Satsuki; Qi, Wei; Sato, Shun; Suzuki, Yo; Fujiwara, Masaru; Hiramatsu, Hiroyuki; Suzuki, Satoru; Abeygunawardhana, P. K. W.; Wada, Kenji; Nishiyama, Akira; Ishimaru, Ichiro

    2015-03-01

    For simultaneous measurement of multi-components on-site like factories, the ultra-compact (diameter: 9[mm], length: 45[mm], weight: 200[g]) one-shot ATR (Attenuated Total Reflection) Fourier spectroscopic imager was proposed. Because the proposed one-shot Fourier spectroscopic imaging is based on spatial-phase-shift interferometer, interferograms could be obtained with simple optical configurations. We introduced the transmission-type relativeinclined phase-shifter, that was constructed with a cuboid prism and a wedge prism, onto the optical Fourier transform plane of infinity corrected optical systems. And also, small light-sources and cameras in the mid-infrared light region, whose size are several millimeter on a side, are essential components for the ultra-compact spectroscopic configuration. We selected the Graphite light source (light source area: 1.7×1.7[mm], maker: Hawkeye technologies) whose radiation factor was high. Fortunately, in these days we could apply the cost-effective 2-dimensional light receiving device for smartphone (e.g. product name: LEPTON, maker: FLIR, price: around 400USD). In the case of alcoholic drinks factory, conventionally workers measure glucose and ethanol concentrations by bringing liquid solution back to laboratories every day. The high portable spectroscopy will make it possible to measure multi-components simultaneously on manufacturing scene. But we found experimentally that absorption spectrum of glucose and water and ethanol were overlapped each other in near infrared light region. But for mid-infrared light region, we could distinguish specific absorption peaks of glucose (@10.5[μm]) and ethanol (@11.5[μm]) independently from water absorption. We obtained standard curve between absorption (@9.6[μm]) and ethanol concentration with high correlation coefficient 0.98 successfully by ATR imaging-type 2-dimensional Fourier spectroscopy (wavelength resolution: 0.057[μm]) with the graphite light source (maker: Hawkeye

  3. Advances in simultaneous atmospheric profile and cloud parameter regression based retrieval from high-spectral resolution radiance measurements

    Weisz, Elisabeth; Smith, William L.; Smith, Nadia

    2013-06-01

    The dual-regression (DR) method retrieves information about the Earth surface and vertical atmospheric conditions from measurements made by any high-spectral resolution infrared sounder in space. The retrieved information includes temperature and atmospheric gases (such as water vapor, ozone, and carbon species) as well as surface and cloud top parameters. The algorithm was designed to produce a high-quality product with low latency and has been demonstrated to yield accurate results in real-time environments. The speed of the retrieval is achieved through linear regression, while accuracy is achieved through a series of classification schemes and decision-making steps. These steps are necessary to account for the nonlinearity of hyperspectral retrievals. In this work, we detail the key steps that have been developed in the DR method to advance accuracy in the retrieval of nonlinear parameters, specifically cloud top pressure. The steps and their impact on retrieval results are discussed in-depth and illustrated through relevant case studies. In addition to discussing and demonstrating advances made in addressing nonlinearity in a linear geophysical retrieval method, advances toward multi-instrument geophysical analysis by applying the DR to three different operational sounders in polar orbit are also noted. For any area on the globe, the DR method achieves consistent accuracy and precision, making it potentially very valuable to both the meteorological and environmental user communities.

  4. The simultaneous measurement of energy and linear polarization of the scattered radiation in resonant inelastic soft x-ray scattering

    Braicovich, L., E-mail: lucio.braicovich@polimi.it; Minola, M.; Dellea, G.; Ghiringhelli, G. [CNR-SPIN and Dipartimento di Fisica, Politecnico di Milano, piazza Leonardo Da Vinci 32, Milano I-20133 (Italy); Le Tacon, M. [Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart (Germany); Moretti Sala, M.; Morawe, C.; Peffen, J.-Ch.; Yakhou, F.; Brookes, N. B. [European Synchrotron Radiation Facility, 71 Avenue des Martyrs, Grenoble F-38043 (France); Supruangnet, R. [Synchrotron Light Research Institute, Nakhon Ratchasima (Thailand)

    2014-11-15

    Resonant Inelastic X-ray Scattering (RIXS) in the soft x-ray range is an element-specific energy-loss spectroscopy used to probe the electronic and magnetic excitations in strongly correlated solids. In the recent years, RIXS has been progressing very quickly in terms of energy resolution and understanding of the experimental results, but the interpretation of spectra could further improve, sometimes decisively, from a full knowledge of the polarization of incident and scattered photons. Here we present the first implementation, in a high resolution soft-RIXS spectrometer used to analyze the scattered radiation, of a device allowing the measurement of the degree of linear polarization. The system, based on a graded W/B{sub 4}C multilayer mirror installed in proximity of the CCD detector, has been installed on the AXES spectrometer at the ESRF (European Synchrotron Radiation Facility); it has been fully characterized and it has been used for a demonstration experiment at the Cu L{sub 3} edge on a high-T{sub c} superconducting cuprate. The loss in efficiency suffered by the spectrometer equipped with this test facility was a factor 17.5. We propose also a more advanced version, suitable for a routine use on the next generation of RIXS spectrometers and with an overall efficiency up to 10%.

  5. Dual isotope Schilling test for measuring absorption of food-bound and free vitamin B12 simultaneously

    Doscherholmen, A.; Silvis, S.; McMahon, J.

    1983-01-01

    A prototype food-bound vitamin B12 (food-B12) absorption test has been developed in which 57 Co-B12 was incorporated in vitro into egg yolk (yolk-B12) and served to volunteers in 50-g cooked portions together with toast and coffee for breakfast. Six hours later, 1 mg nonlabeled B12 was given intramuscularly and 24-hour urine was collected for radioactivity measurement. In separate tests, the absorption of yolk-B12 and crystalline 57 Co-B12 was equally poor in patients with pernicious anemia. However, in patients with simple gastric achlorhydria and those who had undergone gastric surgery, the assimilation of yolk-B12 was impaired greatly, whereas the absorption of crystalline radio-B12 was normal. Egg yolk labeled with 58 Co-B12 was administered together with crystalline 57 Co-B12 in a dual isotope test with results similar to those obtained when the tests were prepared separately. This yolk- 58 Co-B12 test with its ability to detect malabsorption of food-B12 may be considered as an addition to the first part of the Schilling test

  6. Effects of ferumoxytol on quantitative PET measurements in simultaneous PET/MR whole-body imaging: a pilot study in a baboon model.

    Borra, Ronald Jh; Cho, Hoon-Sung; Bowen, Spencer L; Attenberger, Ulrike; Arabasz, Grae; Catana, Ciprian; Josephson, Lee; Rosen, Bruce R; Guimaraes, Alexander R; Hooker, Jacob M

    2015-12-01

    Simultaneous PET/MR imaging depends on MR-derived attenuation maps (mu-maps) for accurate attenuation correction of PET data. Currently, these maps are derived from gradient-echo-based MR sequences, which are sensitive to susceptibility changes. Iron oxide magnetic nanoparticles have been used in the measurement of blood volume, tumor microvasculature, tumor-associated macrophages, and characterizing lymph nodes. Our aim in this study was to assess whether the susceptibility effects associated with iron oxide nanoparticles can potentially affect measured (18)F-FDG PET standardized uptake values (SUV) through effects on MR-derived attenuation maps. The study protocol was approved by the Institutional Animal Care and Use Committee. Using a Siemens Biograph mMR PET/MR scanner, we evaluated the effects of increasing concentrations of ferumoxytol and ferumoxytol aggregates on MR-derived mu-maps using an agarose phantom. In addition, we performed a baboon experiment evaluating the effects of a single i.v. ferumoxytol dose (10 mg/kg) on the liver, spleen, and pancreas (18)F-FDG SUV at baseline (ferumoxytol-naïve), within the first hour and at 1, 3, 5, and 11 weeks. Phantom experiments showed mu-map artifacts starting at ferumoxytol aggregate concentrations of 10 to 20 mg/kg. The in vivo baboon data demonstrated a 53% decrease of observed (18)F-FDG SUV compared to baseline within the first hour in the liver, persisting at least 11 weeks. A single ferumoxytol dose can affect measured SUV for at least 3 months, which should be taken into account when administrating ferumoxytol in patients needing sequential PET/MR scans. Advances in knowledge 1. Ferumoxytol aggregates, but not ferumoxytol alone, produce significant artifacts in MR-derived attenuation correction maps at approximate clinical dose levels of 10 mg/kg. 2. When performing simultaneous whole-body (18)F-FDG PET/MR, a single dose of ferumoxytol can result in observed SUV decreases up to 53%, depending on the

  7. Simultaneous retrieval of water vapour, temperature and cirrus clouds properties from measurements of far infrared spectral radiance over the Antarctic Plateau

    Di Natale, Gianluca; Palchetti, Luca; Bianchini, Giovanni; Del Guasta, Massimo

    2017-03-01

    The possibility separating the contributions of the atmospheric state and ice clouds by using spectral infrared measurements is a fundamental step to quantifying the cloud effect in climate models. A simultaneous retrieval of cloud and atmospheric parameters from infrared wideband spectra will allow the disentanglement of the spectral interference between these variables. In this paper, we describe the development of a code for the simultaneous retrieval of atmospheric state and ice cloud parameters, and its application to the analysis of the spectral measurements acquired by the Radiation Explorer in the Far Infrared - Prototype for Applications and Development (REFIR-PAD) spectroradiometer, which has been in operation at Concordia Station on the Antarctic Plateau since 2012. The code performs the retrieval with a computational time that is comparable with the instrument acquisition time. Water vapour and temperature profiles and the cloud optical and microphysical properties, such as the generalised effective diameter and the ice water path, are retrieved by exploiting the 230-980 cm-1 spectral band. To simulate atmospheric radiative transfer, the Line-By-Line Radiative Transfer Model (LBLRTM) has been integrated with a specifically developed subroutine based on the δ-Eddington two-stream approximation, whereas the single-scattering properties of cirrus clouds have been derived from a database for hexagonal column habits. In order to detect ice clouds, a backscattering and depolarisation lidar, co-located with REFIR-PAD has been used, allowing us to infer the position and the cloud thickness to be used in the retrieval. A climatology of the vertical profiles of water vapour and temperature has been performed by using the daily radiosounding available at the station at 12:00 UTC. The climatology has been used to build an a priori profile correlation to constrain the fitting procedure. An optimal estimation method with the Levenberg-Marquardt approach has been

  8. Simultaneous Measurement of Zinc, Copper, Lead and Cadmium in Baby Weaning Food and Powder Milk by DPASV.

    Sadeghi, Naficeh; Oveisi, Mohammad Reza; Jannat, Behrooz; Hajimahmoodi, Mannan; Behfar, Abdolazim; Behzad, Masoomeh; Norouzi, Narges; Oveisi, Morvarid; Jannat, Behzad

    2014-01-01

    Apart from the breast milk, infant formula and baby weaning food have a special role in infant diet. Infants and young children are very susceptible to amount of trace elements. Copper and zinc are two elements that add in infant food. Lead and cadmium are heavy metals that enter to food chain unavoidably. DPASV is a benefit and applicable method for measurement of trace elements in food products. In this study, concentration of zinc, copper, lead and cadmium in four brands of baby food (rice and wheat based) and powder milk was analyzed with DPASV and polarograph set. Total Mean ± SE of zinc, copper, lead and cadmium in baby foods (n = 240) were 11.86 ± 1.474 mg/100g, 508.197 ± 83.154 μg/100g, 0.445 ± 0.006, 0.050 ± 0.005 mg/Kg respectively. Also these amount in powder milk (n = 240) were 3.621± 0.529 mg/100g, 403.822 ± 133.953 μg/100g, 0.007 ± 0.003, 0.060 ± 0.040 mg/Kg respectively. Zinc level in baby food type I was higher than lablled value (P = 0.030), but in other brands was not difference. Concentration of copper in all of samples was in labeled range (P > 0.05). In each four products, level of lead and cadmium were lower than the standard limit (P < 0.05). Amount of zinc and lead in baby food I, had difference versus other products. Concentration of zinc, camium in baby food type I, was higher than type II (P = 0.043, 0.001 respectively). Concentration of lead and cadmium in baby food type II, was higher than infant formulas, but are in standard limit.

  9. Enhanced Measurements of Chromophoric Dissolved Organic Matter (CDOM) for Water Quality Analysis using a New Simultaneous Absorbance and Fluorescence Instrument

    Gilmore, A. M.

    2009-12-01

    Water quality, with respect to suspended particles and dissolved organic and inorganic compounds, is now recognized as one of the top global environmental concerns. Contemporary research indicates fluorescence spectral analyses coupled with UV-VIS absorbance assays have the potential, especially when combined and coordinated, to facilitate rapid, robust quantification of a wide range of compounds, including interactions among them. Fluorescence excitation-emission matrices (EEMs) collected over the UV-VIS region provide a wealth of information on chromophoric dissolved organic matter (CDOM). CDOM includes humic and fulvic acid, chlorophyll, petroleum, protein, amino acid, quinone, fertilizer, pesticide, sewage and numerous other compound classes. Analysis of the EEMs using conventional and multivariate techniques, including primarily parallel factor analysis (PARAFAC), provides information about many types of CDOM relevant to carbon cycling and pollution of fresh, marine and drinking water sources. Of critical concern also are the CDOM interactions with, and optical activities of, dissolved inorganic compounds. Many of the inorganic compounds and oxygen demand parameters can be analyzed with a wide range of UV-VIS absorbance assays. The instrument is designed and optimized for high UV throughput and low stray light performance. The sampling optics are optimized for both fluorescence and absorbance detection with the same sample. Both EEM and absorbance measurements implement NIST traceable instrument correction and calibration routines. The fluorescence detection utilizes a high dynamic range CCD coupled to a high-resolution spectrograph while absorbance utilizes diode based detection with a high dynamic range and extremely low-stray light specifications. The CDOM analysis is facilitated by a transfer of the data and model information with the PARAFAC routine. The EEM analysis software package facilitates coordinated correction of and correlation with the

  10. Fault Detection and Isolation for Spacecraft

    Jensen, Hans-Christian Becker; Wisniewski, Rafal

    2002-01-01

    This article realizes nonlinear Fault Detection and Isolation for actuators, given there is no measurement of the states in the actuators. The Fault Detection and Isolation of the actuators is instead based on angular velocity measurement of the spacecraft and knowledge about the dynamics...... of the satellite. The algorithms presented in this paper are based on a geometric approach to achieve nonlinear Fault Detection and Isolation. The proposed algorithms are tested in a simulation study and the pros and cons of the algorithms are discussed....

  11. Time maintenance system for the BMDO MSX spacecraft

    Hermes, Martin J.

    1994-01-01

    The Johns Hopkins University Applied Physics Laboratory (APL) is responsible for designing and implementing a clock maintenance system for the Ballistic Missile Defense Organizations (BMDO) Midcourse Space Experiment (MSX) spacecraft. The MSX spacecraft has an on-board clock that will be used to control execution of time-dependent commands and to time tag all science and housekeeping data received from the spacecraft. MSX mission objectives have dictated that this spacecraft time, UTC(MSX), maintain a required accuracy with respect to UTC(USNO) of +/- 10 ms with a +/- 1 ms desired accuracy. APL's atomic time standards and the downlinked spacecraft time were used to develop a time maintenance system that will estimate the current MSX clock time offset during an APL pass and make estimates of the clock's drift and aging using the offset estimates from many passes. Using this information, the clock's accuracy will be maintained by uplinking periodic clock correction commands. The resulting time maintenance system is a combination of offset measurement, command/telemetry, and mission planning hardware and computing assets. All assets provide necessary inputs for deciding when corrections to the MSX spacecraft clock must be made to maintain its required accuracy without inhibiting other mission objectives. The MSX time maintenance system is described as a whole and the clock offset measurement subsystem, a unique combination of precision time maintenance and measurement hardware controlled by a Macintosh computer, is detailed. Simulations show that the system estimates the MSX clock offset to less than+/- 33 microseconds.

  12. Artist concept of Galileo spacecraft

    1988-01-01

    Galileo spacecraft is illustrated in artist concept. Gallileo, named for the Italian astronomer, physicist and mathematician who is credited with construction of the first complete, practical telescope in 1620, will make detailed studies of Jupiter. A cooperative program with the Federal Republic of Germany the Galileo mission will amplify information acquired by two Voyager spacecraft in their brief flybys. Galileo is a two-element system that includes a Jupiter-orbiting observatory and an entry probe. Jet Propulsion Laboratory (JPL) is Galileo project manager and builder of the main spacecraft. Ames Research Center (ARC) has responsibility for the entry probe, which was built by Hughes Aircraft Company and General Electric. Galileo will be deployed from the payload bay (PLB) of Atlantis, Orbiter Vehicle (OV) 104, during mission STS-34.

  13. Simultaneous measurement of 239Pu, 240Pu, 241Pu, and 242Pu by high resolution inductively coupled plasma mass spectrometer (HR ICP-MS) in marine sediments

    Bruneau, F.

    1999-01-01

    Transuranics elements are of particular interest in radioecological studies because of their radiotoxicity and their potential use to decipher source fingerprints and transport processes. The simultaneous measurement of 239 Pu, 240 Pu, 241 Pu, and 242 Pu in environmental samples requires a specific chemical procedure. This work deals with an analytical procedure which yields a very high grade of purification of Pu suitable for ultra low level detection by HR ICP-MS, from marine sediments. After the elimination of major elements (Fe, Al, Mg...) by a first chromatographic separation, a new device of purification by solvent extraction and concentration by a second chromatographic separation is used to obtain a concentrated and high purified solution of plutonium. The chemical procedure have been validated on IAEA certified sediment samples and on sediment samples collected in the roads of Cherbourg which had been previously analysed by other techniques (a spectrometry and thermo-ionisation mass spectrometer). (author)

  14. Simultaneous measurement of temperature and tensile loading using superstructure FBGs developed by laser direct writing of periodic on-fiber metallic films

    Alemohammad, Hamidreza; Toyserkani, Ehsan

    2009-01-01

    This paper addresses the development of superstructure fiber Bragg gratings (FBGs) by laser-assisted direct writing of on-fiber metallic films. A novel laser direct write method is characterized to fabricate periodic films of silver nanoparticles on the non-planar surface of as-fabricated FBGs. Silver films with a thickness of 9 µm are fabricated around a Bragg grating optical fiber. The performance of the superstructure FBG is studied by applying temperature and tensile stress on the fiber. An opto-mechanical model is also developed to predict the optical response of the synthesized superstructure FBG under thermal and structural loadings. The results show that the reflectivity of sidebands in the reflection spectrum can be tuned up to 20% and 37% under thermal and structural loadings, respectively. In addition, the developed superstructure FBG is used for simultaneous measurement of force and temperature to eliminate the inherent limitation of regular FBGs in multi-parameter sensing

  15. Simultaneous measurement of dynamic force and spatial thin film thickness between deformable and solid surfaces by integrated thin liquid film force apparatus.

    Zhang, Xurui; Tchoukov, Plamen; Manica, Rogerio; Wang, Louxiang; Liu, Qingxia; Xu, Zhenghe

    2016-11-09

    Interactions involving deformable surfaces reveal a number of distinguishing physicochemical characteristics that do not exist in interactions between rigid solid surfaces. A unique fully custom-designed instrument, referred to as integrated thin liquid film force apparatus (ITLFFA), was developed to study the interactions between one deformable and one solid surface in liquid. Incorporating a bimorph force sensor with interferometry, this device allows for the simultaneous measurement of the time-dependent interaction force and the corresponding spatiotemporal film thickness of the intervening liquid film. The ITLFFA possesses the specific feature of conducting measurement under a wide range of hydrodynamic conditions, with a displacement velocity of deformable surfaces ranging from 2 μm s -1 to 50 mm s -1 . Equipped with a high speed camera, the results of a bubble interacting with hydrophilic and partially hydrophobic surfaces in aqueous solutions indicated that ITLFFA can provide information on interaction forces and thin liquid film drainage dynamics not only in a stable film but also in films of the quick rupture process. The weak interaction force was extracted from a measured film profile. Because of its well-characterized experimental conditions, ITLFFA permits the accurate and quantitative comparison/validation between measured and calculated interaction forces and temporal film profiles.

  16. Simultaneous measurement of glucose blood–brain transport constants and metabolic rate in rat brain using in-vivo 1H MRS

    Du, Fei; Zhang, Yi; Zhu, Xiao-Hong; Chen, Wei

    2012-01-01

    Cerebral glucose consumption and glucose transport across the blood–brain barrier are crucial to brain function since glucose is the major energy fuel for supporting intense electrophysiological activity associated with neuronal firing and signaling. Therefore, the development of noninvasive methods to measure the cerebral metabolic rate of glucose (CMRglc) and glucose transport constants (KT: half-saturation constant; Tmax: maximum transport rate) are of importance for understanding glucose transport mechanism and neuroenergetics under various physiological and pathological conditions. In this study, a novel approach able to simultaneously measure CMRglc, KT, and Tmax via monitoring the dynamic glucose concentration changes in the brain tissue using in-vivo 1H magnetic resonance spectroscopy (MRS) and in plasma after a brief glucose infusion was proposed and tested using an animal model. The values of CMRglc, Tmax, and KT were determined to be 0.44±0.17 μmol/g per minute, 1.35±0.47 μmol/g per minute, and 13.4±6.8 mmol/L in the rat brain anesthetized with 2% isoflurane. The Monte-Carlo simulations suggest that the measurements of CMRglc and Tmax are more reliable than that of KT. The overall results indicate that the new approach is robust and reliable for in-vivo measurements of both brain glucose metabolic rate and transport constants, and has potential for human application. PMID:22714049

  17. Fluence measurements applied to 5-20 MeV/amu ion beam dosimetry by simultaneous use of a total-absorption calorimeter and a Faraday cup

    Kojima, T; Takizawa, H; Tachibana, H; Tanaka, R

    1998-01-01

    A Faraday cup was fabricated for measuring the beam current of a few tens MeV/amu ion beams of the TIARA AVF cyclotron. It has been applied as a beam monitor for studying the characteristics of film dosimeters that are well-established for high doses of sup 6 sup 0 Co gamma-rays and 1 to 10 MeV electrons. A total absorption calorimeter designed to measure energy fluence has also been tested for estimating the uncertainty in fluence measurement of 5-20 MeV/amu ion beams, by simultaneous use of the calorimeter and the Faraday cup in a broad uniform fluence field. The estimated fluence was evaluated on the basis of nominal particle energy values derived from the cyclotron acceleration parameters. The average ratio of the measured fluence values to the estimated values is 1.024, and the average precision is within +-2% at a 68% confidence level, for most of the ion beams with a range of kinetic energy per nucleon, 5-20 MeV/amu, at an integrated charge above 5 nC/cm sup 2.

  18. Passive coherent discriminator using phase diversity for the simultaneous measurement of frequency noise and intensity noise of a continuous-wave laser

    Michaud-Belleau, V.; Bergeron, H.; Light, P. S.; Hébert, N. B.; Deschênes, J. D.; Luiten, A. N.; Genest, J.

    2016-10-01

    The frequency noise and intensity noise of a laser set the performance limits in many modern photonics applications and, consequently, must often be characterized. As lasers continue to improve, the measurement of these noises however becomes increasingly challenging. Current approaches for the characterization of very high-performance lasers often call for a second laser with equal or higher performance to the one that is to be measured, an incoherent interferometer having an extremely long delay-arm, or an interferometer that relies on an active device. These instrumental features can be impractical or problematic under certain experimental conditions. As an alternative, this paper presents an entirely passive coherent interferometer that employs an optical 90° hybrid coupler to perform in-phase and quadrature detection. We demonstrate the technique by measuring the frequency noise power spectral density of a highly-stable 192 THz (1560 nm) fiber laser over five frequency decades. Simultaneously, we are able to measure its relative intensity noise power spectral density and characterize the correlation between its amplitude noise and phase noise. We correct some common misconceptions through a detailed theoretical analysis and demonstrate the necessity to account for normal imperfections of the optical 90° hybrid coupler. We finally conclude that this passive coherent discriminator is suitable for reliable and simple noise characterization of highly-stable lasers, with bandwidth and dynamic range benefits but susceptibility to additive noise contamination.

  19. Oxygen surface exchange kinetics measurement by simultaneous optical transmission relaxation and impedance spectroscopy: Sr(Ti,Fe)O3-x thin film case study.

    Perry, Nicola H; Kim, Jae Jin; Tuller, Harry L

    2018-01-01

    We compare approaches to measure oxygen surface exchange kinetics, by simultaneous optical transmission relaxation (OTR) and AC-impedance spectroscopy (AC-IS), on the same mixed conducting SrTi 0.65 Fe 0.35 O 3-x film. Surface exchange coefficients were evaluated as a function of oxygen activity in the film, controlled by gas partial pressure and/or DC bias applied across the ionically conducting yttria-stabilized zirconia substrate. Changes in measured light transmission through the film over time (relaxations) resulted from optical absorption changes in the film corresponding to changes in its oxygen and oxidized Fe (~Fe 4+ ) concentrations; such relaxation profiles were successfully described by the equation for surface exchange-limited kinetics appropriate for the film geometry. The k chem values obtained by OTR were significantly lower than the AC-IS derived k chem values and k q values multiplied by the thermodynamic factor (bulk or thin film), suggesting a possible enhancement in k by the metal current collectors (Pt, Au). Long-term degradation in k chem and k q values obtained by AC-IS was also attributed to deterioration of the porous Pt current collector, while no significant degradation was observed in the optically derived k chem values. The results suggest that, while the current collector might influence measurements by AC-IS, the OTR method offers a continuous, in situ , and contact-free method to measure oxygen exchange kinetics at the native surfaces of thin films.

  20. Polar cap mesosphere wind observations: comparisons of simultaneous measurements with a Fabry-Perot interferometer and a field-widened Michelson interferometer.

    Fisher, G M; Killeen, T L; Wu, Q; Reeves, J M; Hays, P B; Gault, W A; Brown, S; Shepherd, G G

    2000-08-20

    Polar cap mesospheric winds observed with a Fabry-Perot interferometer with a circle-to-line interferometer optical (FPI/CLIO) system have been compared with measurements from a field-widened Michelson interferometer optimized for E-region winds (ERWIN). Both instruments observed the Meinel OH emission emanating from the mesopause region (approximately 86 km) at Resolute Bay, Canada (74.9 degrees N, 94.9 degrees W). This is the first time, to our knowledge, that winds measured simultaneously from a ground-based Fabry-Perot interferometer and a ground-based Michelson interferometer have been compared at the same location. The FPI/CLIO and ERWIN instruments both have a capability for high temporal resolution (less than 10 min for a full scan in the four cardinal directions and the zenith). Statistical comparisons of hourly mean winds for both instruments by scatterplots show excellent agreement, indicating that the two optical techniques provide equivalent observations of mesopause winds. Small deviations in the measured wind can be ascribed to the different zenith angles used by the two instruments. The combined measurements illustrate the dominance of the 12-h wave in the mesopause winds at Resolute Bay, with additional evidence for strong gravity wave activity with much shorter periods (tens of minutes). Future operations of the two instruments will focus on observation of complementary emissions, providing a unique passive optical capability for the determination of neutral winds in the geomagnetic polar cap at various altitudes near the mesopause.