Zeitschriftenartikel: „Simultaneous multichannel measurement“

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Steffen, Matthias, Konrad Heimann, Nina Bernstein und Steffen Leonhardt. „Multichannel simultaneous magnetic induction measurement system (MUSIMITOS)“. Physiological Measurement 29, Nr. 6 (01.06.2008): S291—S306. http://dx.doi.org/10.1088/0967-3334/29/6/s25.

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Gerhards, Holger, Ute Wollschläger, Qihao Yu, Philip Schiwek, Xicai Pan und Kurt Roth. „Continuous and simultaneous measurement of reflector depth and average soil-water content with multichannel ground-penetrating radar“. GEOPHYSICS 73, Nr. 4 (Juli 2008): J15—J23. http://dx.doi.org/10.1190/1.2943669.

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Ground-penetrating radar is a fast noninvasive technique that can monitor subsurface structure and water-content distribution. To interpret traveltime information from single common-offset measurements, additional assumptions, such as constant permittivity, usually are required. We present a fast ground-penetrating-radar measurement technique using a multiple transmitter-and-receiver setup to measure simultaneously the reflector depth and average soil-water content. It can be considered a moving minicommon-midpoint measurement. For a simple analysis, we use a straightforward evaluation procedure that includes two traveltimes to the same reflector, obtained from different antenna separations. For a more accurate approach, an inverse evaluation procedure is added, using traveltimes obtained from all antenna separations at one position and its neighboring measurement locations. The evaluation of a synthetic data set with a lateral variability in reflector depth and an experimental example with a large variability in soil-water content are introduced to demonstrate the applicability for field-scale measurements. The crucial point for this application is the access to absolute traveltimes, which are difficult to determine accurately from common-offset measurements.

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Rollow, Douglas, und David C. Swanson. „Applications of binary noiselike sequences to the simultaneous measurement of multichannel system functions“. Journal of the Acoustical Society of America 101, Nr. 5 (Mai 1997): 3114. http://dx.doi.org/10.1121/1.418951.

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4

Nikolic, Aleksandar B., Blagoje Babic, Aleksandar Zigic, Nikola Miladinovic und Srdjan Milosavljevic. „Simultaneous power quality analysis of feeders in MV utility power stations“. ACTA IMEKO 4, Nr. 1 (05.02.2015): 53. http://dx.doi.org/10.21014/acta_imeko.v4i1.163.

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The development of a low-cost, space saving device that could simultaneously take measurements from all (usually eight or up to twelve) outgoing three-phase feeders in a distribution substation is presented in this paper. To meet these requirements, at least 3 voltage measurements and 36 current measurements should be performed at the same time. In order to save space but not to reduce the measurement accuracy, a data acquisition system is designed based on real-time multiprocessing with a microcontroller and an FPGA circuit. Voltage and current measurements and their corresponding higher-order harmonics are calculated using a fast FPGA circuit, while other calculations (power, power factor, voltage and current phase angles, etc.) are performed in the microcontroller. Further savings are obtained using multichannel analog input modules with multiplexed inputs. Communication with the supervising computer is done using a GPRS modem or wireless network module depending of the station location. Results obtained in the laboratory and later in an industrial prototype confirm the proposed solution.

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Meoni, Andrea, Antonella D’Alessandro, Massimo Mancinelli und Filippo Ubertini. „A Multichannel Strain Measurement Technique for Nanomodified Smart Cement-Based Sensors in Reinforced Concrete Structures“. Sensors 21, Nr. 16 (21.08.2021): 5633. http://dx.doi.org/10.3390/s21165633.

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Nanomodified smart cement-based sensors are an emerging self-sensing technology for the structural health monitoring (SHM) of reinforced concrete (RC) structures. To date, several literature works demonstrated their strain-sensing capabilities, which make them suited for damage detection and localization. Despite the most recent technological improvements, a tailored measurement technique allowing feasible field implementations of smart cement-based sensors to concrete structures is still missing. In this regard, this paper proposes a multichannel measurement technique for retrieving strains from smart cement-based sensors embedded in RC structures using a distributed biphasic input. The experiments performed for its validation include the investigation on an RC beam with seven embedded sensors subjected to different types of static loading and a long-term monitoring application on an RC plate. Results demonstrate that the proposed technique is effective for retrieving time-stable simultaneous strain measurements from smart cement-based sensors, as well as for aiding the identification of the changes in their electrical outputs due to the influence of environmental effects variable over time. Accordingly, the proposed multichannel strain measurement technique represents a promising approach for performing feasible field implementations of smart cement-based sensors to concrete structures.

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González, F., M. P. Cagigal und M. A. Rebolledo. „Application of Photon Correlation and Multichannel Analysis Techniques to the Measurement of a Two-Line Spectrum: Simultaneous Determination of All Parameters“. Applied Spectroscopy 40, Nr. 7 (September 1986): 959–62. http://dx.doi.org/10.1366/0003702864508070.

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In this paper the analysis of two spectral lines by using a digital correlator or a digital multichannel analyzer is studied by means of experiment and a computer simulation method. The errors involved in the simultaneous determination of the width, separation, and relative height of the lines are studied and compared.

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Axelsson, M., Q. Dang, K. Pitsillides, S. Munns, J. Hicks und G. S. Kassab. „A novel, fully implantable, multichannel biotelemetry system for measurement of blood flow, pressure, ECG, and temperature“. Journal of Applied Physiology 102, Nr. 3 (März 2007): 1220–28. http://dx.doi.org/10.1152/japplphysiol.00887.2006.

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Biotelemetry provides high-quality data in awake, free-ranging animals without the effects of anesthesia and surgery. Although many biological parameters can be measured using biotelemetry, simultaneous telemetric measurements of pressure and flow have not been available. The objective of this study was to evaluate simultaneous measurements of blood flow, pressure, ECG, and temperature in a fully implantable system. This novel system allows the measurement of up to four channels of blood flow, up to three channels of pressure, and a single channel each of ECG and temperature. The system includes a bidirectional radio-frequency link that allows the implant to send data and accept commands to perform various tasks. The system is controlled by a base station decoder/controller that decodes the data stream sent by the implant into analog signals. The system also converts the data into a digital data stream that can be sent via ethernet to a remote computer for storage and/or analysis. The system was chronically implanted in swine and alligators for up to 5 wk. Both bench and in vivo animal tests were performed to evaluate system performance. Results show that this biotelemetry system is capable of long-term accurate monitoring of simultaneous blood flow and pressure. The system allows, within the room, recordings, since the implant transmission range is between 6 and 10 m, and, with a relay, backpack transmission distance of up to 500 m can be achieved. This system will have significant utility in chronic models of cardiovascular physiology and pathology.

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Hebden, Jeremy C., Florian E. W. Schmidt, Martin E. Fry, Martin Schweiger, Elizabeth M. C. Hillman, David T. Delpy und Simon R. Arridge. „Simultaneous reconstruction of absorption and scattering images by multichannel measurement of purely temporal data“. Optics Letters 24, Nr. 8 (15.04.1999): 534. http://dx.doi.org/10.1364/ol.24.000534.

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Vondra, Vlastimil, Pavel Jurak, Ivo Viscor, Josef Halamek, Pavel Leinveber, Magdalena Matejkova und Ladislav Soukup. „A multichannel bioimpedance monitor for full-body blood flow monitoring“. Biomedical Engineering / Biomedizinische Technik 61, Nr. 1 (01.02.2016): 107–18. http://dx.doi.org/10.1515/bmt-2014-0108.

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Abstract The design, properties, and possible diagnostic contribution of a multichannel bioimpedance monitor (MBM) with three independent current sources are presented in this paper. The simultaneous measurement of bioimpedance at 18 locations (the main part of the body, legs, arms, and neck) provides completely new information, on the basis of which more precise haemodynamic parameters can be obtained. The application of the MBM during various haemodynamic stages, such as resting in a supine position, tilting, exercise stress, and various respiration manoeuvres, is demonstrated. Statistical analysis on a group of 34 healthy volunteers is presented for demonstration of blood flow monitoring by using the proposed method.

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Shi, Peiwan, Zhongbing Shi, Wei Chen, Wulyu Zhong, Zengchen Yang, Min Jiang, Boyu Zhang et al. „Multichannel Microwave Interferometer for Simultaneous Measurement of Electron Density and its Fluctuation on HL-2A Tokamak“. Plasma Science and Technology 18, Nr. 7 (28.06.2016): 708–13. http://dx.doi.org/10.1088/1009-0630/18/7/02.

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Przysowa, Radoslaw, und Peter Russhard. „Non-Contact Measurement of Blade Vibration in an Axial Compressor“. Sensors 20, Nr. 1 (21.12.2019): 68. http://dx.doi.org/10.3390/s20010068.

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Complex blade responses such as a rotating stall or simultaneous resonances are common in modern engines and their observation can be a challenge even for state-of-the-art tip-timing systems and trained operators. This paper analyses forced vibrations of axial compressor blades, measured during the bench tests of the SO-3 turbojet. In relation to earlier studies conducted in Poland with a small number of sensors, a multichannel tip-timing system let us observe simultaneous responses or higher-order modes. To find possible symptoms of a failure, blade responses in a healthy and unhealthy engine configuration with an inlet blocker were studied. The used analysis methods covered all-blade spectrum and the circumferential fitting of blade deflections to the harmonic oscillator model. The Pearson coefficient of correlation between the measured and predicted tip deflection is calculated to evaluate fitting results. It helps to avoid common operator mistakes and misinterpreting the results. The proposed modal solver can track the vibration frequency and adjust the engine order on the fly. That way, synchronous and asynchronous vibrations are observed and analysed together with an extended variant of least squares. This approach saves a lot of work related to configuring the conventional tip-timing solver.

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Lyu, G. Y., S. S. Lee, D. H. Lee, C. S. Park, M. H. Kang und K. Cho. „Simultaneous measurement of multichannel laser linewidths and spacing by use of stimulated Brillouin scattering in optical fiber“. Optics Letters 23, Nr. 11 (01.06.1998): 873. http://dx.doi.org/10.1364/ol.23.000873.

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Husain, Mirna, As’ari _ und Seni H. J. Tongkukut. „Pemetaan Aair Tanah Menggunakan Metode Geolistrik Tahanan Jenis Konfigurasi Dipol-dipol Di Universitas Sam Ratulangi“. Jurnal MIPA 6, Nr. 1 (19.06.2017): 78. http://dx.doi.org/10.35799/jm.6.1.2017.16175.

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Telah dilakukan penelitian untuk mendeteksi keberadaan air tanah di area Universitas Sam Ratulangi. Penelitian ini menggunakan metode geolistrik resistivitas tahanan jenis konfigurasi Dipol-dipol. Akuisisi data menggunakan Multichannel and Multielectrode resistivity an IP meter 48 simultaneous channel merek MAE X 612-EM. Pengukuran dilakukan pada 11 lintasan dengan panjang masing-masing lintasan 480 meter. Pengolahan data dilakukan dengan menggunakan perangkat lunak Res2Dinv dengan hasil berupa gambar tampang lintang resistivitas model bawah permukaan 2D yang digunakan untuk menentukan posisi akuifer air tanah.Hasil menunujukkan bahwa adanya lapisan batuan dengan nilai resistivitas rendah yaitu 280 Ωm. Nilai resistivitas yang merupakan lapisan pembawa air adalah 25,93 Ωm. Posisi akuifer diperoleh pada lintasan 1, 3, 5, 7, 8 dan 9.of Sam Ratulangi area.The research used the dipole-dipole configuration resistivity geoelectic method. Data acquisitions is using Multichannel and Multielectrode resistivity an IP meter 48 simultaneous channel of MAE X 612-EM types. The measurement is done on 11 lines with length of each line is 480 meters. Data processing has been done by using Res2Dinv software and resulted of 2D resistivity subsurface model which used to determine the groundwater aquifer position.The results show that the existence of rock layer with low resistivity is 280 Ωm. The resistivity of rock layer of the water aquifer is 25,93 Ωm. Position of aquifer are obtained in the 1,3,5,7,8, and 9 lines.

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Kubáň, Vlastimil, und Petr Doležel. „Multicomponent determination by flow injection analysis using PU 4021 diode array detector. A direct determination of lanthanoids“. Collection of Czechoslovak Chemical Communications 53, Nr. 3 (1988): 543–53. http://dx.doi.org/10.1135/cccc19880543.

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Flow injection analysis (FIA) using a multichannel UV-VIS diode array detector enables several components with sufficiently separate absorption bands to be determined simultaneously. The effects of the basic parameters of the FIA apparatus (geometry, flow rates, etc.), error of measurement of the analytical signal, mutual interactions between the components to be determined, and the data handling procedure on the accuracy and precision of the calculated concentrations of the components are demonstrated on a model case of binary and ternary mixtures of Cu(II), Ni(II), Co(II), and U(VI). The majority and minority components can be determined with relative errors of 1-3% and 2-20%, respectively, over the concentration region of 2 to 200 mmol l-1 at concentration ratios from 1:1 to 50:1. The method has been applied to a simultaneous determination of Pr(III), Sm(III), and Nd(III) in oxidic concentrates of rare earths over the region of 1 – 20 mg ml-1 at concentration ratios down to 1:10 with relative errors not exceeding 5%.

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Dayev, Zhanat А., Gulzhan E. Shopanova und Bakytgul А. Toksanbaeva. „Invariant method for measuring wet gas flow rate“. Izmeritel`naya Tekhnika, Nr. 6 (2021): 13–19. http://dx.doi.org/10.32446/0368-1025it.2021-6-13-19.

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The article deals with one of the important tasks of modern flow measurement, which is related to the measurement of the flow rate and the amount of wet gas. This task becomes especially important when it becomes necessary to obtain information about the separate amount of the dry part of the gas that is contained in the form of a mixture in the wet gas stream. The paper presents the principle of operation and structure of the invariant system for measuring the flow rate of wet gas, which is based on the combined use of differential pressure flowmeters and Coriolis flowmeters. The operation of the invariant wet gas flow rate measurement system is based on the simultaneous application of the multichannel principle and the partial flow measurement method. Coriolis flowmeters and the differential pressure flowmeter are used as the main elements of the system. The proposed measurement system does not offer applications for gases with abundant drip humidity. The article provides information about the test results of the proposed invariant system. The estimation of the metrological characteristics of the invariant system when measuring the flow rate of wet gas is given. The obtained test results of the invariant wet gas flow rate measurement system are relevant for natural gas production, transportation, and storage facilities.

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Kostić, Dragutin, Vujo Drndarević, Petar Marković und Nenad Jevtić. „DEVELOPMENT OF METHODS FOR ACQUIRING AND TRANSFERING MEASUREMENT DATA IN TESTING THE ELECTRIC LOCOMOTIVES“. TRANSPORT 26, Nr. 4 (09.01.2012): 367–74. http://dx.doi.org/10.3846/16484142.2011.557217.

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The paper describes procedures and methods upon which a system has been developed for testing the running behavior of new or reconstructed electric locomotives prior to release them into regular service. Special attention has been paid to precise measurement of traction currents and voltages, as well as non-electrical quantities, such as torque, longitudinal force exerted at the wheel rim, angular and linear velocity, which vary in a wide range. In addition to choosing appropriate sensors and measuring transducers, specific interface circuits were designed and manufactured, and a laboratory model for measuring electrical and non-electrical quantities of traction electric motors was developed and realised. Based on the experience and the results obtained from the laboratory model, a computerised data acquisition system for testing the electric locomotives in the field was designed from such a computerised systems as application program for simultaneous multichannel measurement of mechanical and electrical quantities, and for off-line processing of measurement results. The systems were tested during the operation on measurement and analysis of tractive capabilities, quality of anti slip regulation system, and energy consumption of a modernized locomotive.

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Nguyen, T. A., D. Echtermeyer, A. Barthel, G. Urban und U. Pliquett. „Multichannel cell detection in microcompartments by means of true parallel measurements using the Solartron S-1260“. Journal of Electrical Bioimpedance 11, Nr. 1 (24.07.2020): 49–56. http://dx.doi.org/10.2478/joeb-2020-0008.

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AbstractDesigning proper frontend electronics is critical in the development of highly sophisticated electrode systems. Multielectrode arrays for measuring electrical signals or impedance require multichannel readout systems. Even more challenging is the differential or ratiometric configuration with simultaneous assessment of measurement and reference channels. In this work, an eight-channel frontend was developed for contacting a 2×8 electrode array (8 measurement and 8 reference electrodes) with a large common electrode to the impedance gain-phase analyzer Solartron 1260 (S-1260). Using the three independent and truly parallel monitor channels of the S-1260, impedance of trapped cells and reference material was measured at the same time, thereby considerably increasing the performance of the device. The frontend electronics buffers the generator output and applies a potentiostatic signal to the common electrode of the chip. The applied voltage is monitored using the current monitor of the S-1260 via voltage/current conversion. The frontend monitors the current through the electrodes and converts it to a voltage fed into the voltage monitors of the S-1260. For assessment of the 8 electrode pairs featured by the chip, a relay-based multiplexer was implemented. Extensive characterization and calibration of the frontend were carried out in a frequency range between 100 Hz and 1 MHz. Investigating the influence of the multiplexer and the frontend electronics, direct measurement with and without frontend was compared. Although differences were evident, they have been negligible below one per cent. The significance of measurement using the complex S-1260-frontend-electrode was tested using Kohlrausch's law. The impedance of an electrolytic dilution series was measured and compared to the theoretical values. The coincidence of measured values and theoretical prediction serves as an indicator for electrode sensitivity to cell behavior. Monitoring of cell behavior on the microelectrode surface will be shown as an example.

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Doležel, Petr, und Vlastimil Kubáň. „The determination of Cu, Ni, and Co using 2-(2-pyridylazo)-1-naphtol-4-sulfonic acid by multicomponent flow injection analysis (MC-FIA)“. Collection of Czechoslovak Chemical Communications 53, Nr. 6 (1988): 1162–71. http://dx.doi.org/10.1135/cccc19881162.

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2-(2-Pyridylazo)-1-naphthol-4-sulfonic acid (1PAN4S) was used to develop a method for the simultaneous spectrophotometric determination of Cu(II), Ni(II), and Co(III) by reverse flow injection analysis (FIA) using a multichannel UV-VIS detector with a diode array. The method can be used to determine the individual ions in the range 5-50 μmol dm-3 Ni(II) or Cu(II) and 5-60 μmol dm-3 Co(III) in binary and ternary mixtures at ratios of 1 : 1 to 1 : 10 with a maximal relative deviation of units of per cent for the major components and tens of per cent for the minor components. The precision and accuracy of the determination are the same or slightly worse than for stationary measurements with half to one fifth the sensitivity. Measurement of the absorption spectra for the maximum analytical signal in digital form for c(1PAN4S) = 0·12 mmol dm-3, c(NaIO4) = 1·2 mmol dm-3 in 0·2M acetate buffer medium at pH 5·00 permits rapid determination (15 s per sample) of all the components using a simple program for multicomponent analysis in "overdetermined" systems.

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Comesaña, Daniel Fernández, Steven Steltenpool, Graciano Carrillo Pousa, Hans-Elias de Bree und Keith R. Holland. „Scan and Paint: Theory and Practice of a Sound Field Visualization Method“. ISRN Mechanical Engineering 2013 (27.08.2013): 1–11. http://dx.doi.org/10.1155/2013/241958.

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Sound visualization techniques have played a key role in the development of acoustics throughout history. The development of measurement apparatus and techniques for displaying sound and vibration phenomena has provided excellent tools for building understanding about specific problems. Traditional methods, such as step-by-step measurements or simultaneous multichannel systems, have a strong tradeoff between time requirements, flexibility, and cost. However, if the sound field can be assumed time stationary, scanning methods allow us to assess variations across space with a single transducer, as long as the position of the sensor is known. The proposed technique, Scan and Paint, is based on the acquisition of sound pressure and particle velocity by manually moving a P-U probe (pressure-particle velocity sensors) across a sound field whilst filming the event with a camera. The sensor position is extracted by applying automatic color tracking to each frame of the recorded video. It is then possible to visualize sound variations across the space in terms of sound pressure, particle velocity, or acoustic intensity. In this paper, not only the theoretical foundations of the method, but also its practical applications are explored such as scanning transfer path analysis, source radiation characterization, operational deflection shapes, virtual phased arrays, material characterization, and acoustic intensity vector field mapping.

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Bianco, Laura, Domenico Cimini, Frank S. Marzano und Randolph Ware. „Combining Microwave Radiometer and Wind Profiler Radar Measurements for High-Resolution Atmospheric Humidity Profiling“. Journal of Atmospheric and Oceanic Technology 22, Nr. 7 (01.07.2005): 949–65. http://dx.doi.org/10.1175/jtech1771.1.

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Abstract A self-consistent remote sensing physical method to retrieve atmospheric humidity high-resolution profiles by synergetic use of a microwave radiometer profiler (MWRP) and wind profiler radar (WPR) is illustrated. The proposed technique is based on the processing of WPR data for estimating the potential refractivity gradient profiles and their optimal combination with MWRP estimates of potential temperature profiles in order to fully retrieve humidity gradient profiles. The combined algorithm makes use of recent developments in WPR signal processing, computing the zeroth-, first-, and second-order moments of WPR Doppler spectra via a fuzzy logic method, which provides quality control of radar data in the spectral domain. On the other hand, the application of neural network to brightness temperatures, measured by a multichannel MWRP, can provide continuous estimates of tropospheric temperature and humidity profiles. Performance of the combined algorithm in retrieving humidity profiles is compared with simultaneous in situ radiosonde observations (raob’s). The empirical sets of WPR and MWRP data were collected at the Atmospheric Radiation Measurement (ARM) Program’s Southern Great Plains (SGP) site. Combined microwave radiometer and wind profiler measurements show encouraging results and significantly improve the spatial vertical resolution of atmospheric humidity profiles. Finally, some of the limitations found in the use of this technique and possible future improvements are also discussed.

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Tamura, Mamoru, Yoko Hoshi und Fumihiko Okada. „Localized near–infrared spectroscopy and functional optical imaging of brain activity“. Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 352, Nr. 1354 (29.06.1997): 737–42. http://dx.doi.org/10.1098/rstb.1997.0056.

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Changes in cerebral blood flow (CBF) and cerebral metabolic rates (CMRO 2 ) have been used as indices for changes in neuronal activity. Near–infrared spectroscopy (NIRS) can also measure cerebral haemodynamics and metabolic changes, enabling the possible use of multichannel recording of NIRS for functional optical imaging of human brain activity. Spatio–temporal variations of brain regions were demonstrated during various mental tasks. Non–synchronous behaviour of cerebral haemodynamics during the neuronsl activation was observed. Gender– and handedness–dependent lateralization of the function between right and left hemispheres was demonstrated by simultaneous measurement using two NIR instruments during the mirror–drawing task. A lack of interhemispheric integration was observed with schizophrenic patients. These observations suggest an application for NIRS in psychiatric disease management, as an addition to clinical monitoring at the bedside. A time–resolved 64–channel optical imaging system was constructed. This consisted of three picosecond laser diodes and 64 channels of TAC and CFD systems. Image reconstruction for phantom model systems was performed. Time–resolved quantitative optical imaging will become real in the very near future.

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Campbell, W. J., E. G. Josberger, P. Gloersen und A. T. C. Chang. „Microwave Snow-Water Equivalent Mapping of the Upper Colorado River Basin, U.S.A. (Abstract)“. Annals of Glaciology 9 (1987): 244–45. http://dx.doi.org/10.1017/s0260305500000823.

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During spring 1984, a joint agency research effort was made to explore the use of satellite passive microwave techniques to measure snow-water equivalents in the upper Colorado River basin. This study involved the near real-time acquisition of microwave radiances from the Scanning Multichannel Microwave Radiometer (SMMR) aboard the Nimbus-7 satellite, coupled with quasi-simultaneous surface measurements of snow-pack depth and profiles of temperature, density, and crystal size within the basin. A key idea in this study was to compare, for the same space and time-scales, the SMMR synoptic physics data taken in the basin. Such a snow-measurement program was logistically difficult, but two field teams took detailed snow-pit measurements at 18 sites in Colorado, Utah, and Wyoming during the last 2 weeks of March, when the snow-pack is normally at its maximum extent and depth. These observations were coupled with snow-water-equivalent measurements from Soil Conservation Service SNOTEL sites. Microwave- gradient ratio, Gr (Gr is the difference of the vertically polarized radiances at 8 mm and 17 mm divided by the sum), maps of the basin were derived in a near real-time mode every 6 days from SMMR observations. The sequential Gr maps showed anomalously low values in the Wyoming snow-pack when compared to the other states. This near real-time information then directed the field teams to Wyoming to carry out an extensive survey, which showed that these values were due to the presence of depth hoar; the average crystal sizes were more than twice as large as in the other areas. SMMR can be used to monitor the spatial distribution and temporal evolution of crystal size in snow-packs. Also, scatter diagrams of snow-water equivalents from the combined snow-pit and SNOTEL observations versus Gr from the Wyoming part, and the Colorado and Utah part, of the basin can be used to estimate snow-water equivalents for various parts of the basin.

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Campbell, W. J., E. G. Josberger, P. Gloersen und A. T. C. Chang. „Microwave Snow-Water Equivalent Mapping of the Upper Colorado River Basin, U.S.A. (Abstract)“. Annals of Glaciology 9 (1987): 244–45. http://dx.doi.org/10.3189/s0260305500000823.

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During spring 1984, a joint agency research effort was made to explore the use of satellite passive microwave techniques to measure snow-water equivalents in the upper Colorado River basin. This study involved the near real-time acquisition of microwave radiances from the Scanning Multichannel Microwave Radiometer (SMMR) aboard the Nimbus-7 satellite, coupled with quasi-simultaneous surface measurements of snow-pack depth and profiles of temperature, density, and crystal size within the basin. A key idea in this study was to compare, for the same space and time-scales, the SMMR synoptic physics data taken in the basin. Such a snow-measurement program was logistically difficult, but two field teams took detailed snow-pit measurements at 18 sites in Colorado, Utah, and Wyoming during the last 2 weeks of March, when the snow-pack is normally at its maximum extent and depth. These observations were coupled with snow-water-equivalent measurements from Soil Conservation Service SNOTEL sites. Microwave- gradient ratio, Gr (Gr is the difference of the vertically polarized radiances at 8 mm and 17 mm divided by the sum), maps of the basin were derived in a near real-time mode every 6 days from SMMR observations. The sequential Gr maps showed anomalously low values in the Wyoming snow-pack when compared to the other states. This near real-time information then directed the field teams to Wyoming to carry out an extensive survey, which showed that these values were due to the presence of depth hoar; the average crystal sizes were more than twice as large as in the other areas. SMMR can be used to monitor the spatial distribution and temporal evolution of crystal size in snow-packs. Also, scatter diagrams of snow-water equivalents from the combined snow-pit and SNOTEL observations versus Gr from the Wyoming part, and the Colorado and Utah part, of the basin can be used to estimate snow-water equivalents for various parts of the basin.

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Moras, K., und R. Arnhold. „New Possibilities of Phase, Texture, and Stress Analysis Using Energy Dispersive Detectors“. Textures and Microstructures 30, Nr. 3-4 (01.01.1998): 155–66. http://dx.doi.org/10.1155/tsm.30.155.

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For angular dispersive and energy dispersive phase, texture, and stress analysis of compact samples (TiAl) and thin TiN layers, an electroluminescence detector and a Si(Li) semiconductor detector were applied. The parameters and application properties of the detectors are described. For angular dispersive measurements higher reflection intensities and better peak-to-background ratios can be attained, in comparison to conventional methods, by using multichannel pulse accumulation and mathematical spectrum evaluation.In energy dispersive texture and stress measurements, reflection data from several lattice planes can be obtained simultaneously. In stress measurement, variations of lattice spacings in the order of 10-3 are reliably detectable. In principle, texture and stress information can be received from one measurement.

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Zhao, Xin Tong, Xiao Dong Lu, Xi Jun Zhang und Guo Dong Zhang. „Development of Multichannel Data Acquisition System Based on Wheel Load Measuring Plate“. Advanced Materials Research 765-767 (September 2013): 2608–12. http://dx.doi.org/10.4028/www.scientific.net/amr.765-767.2608.

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The wheel load measuring plate is a force sensor based on strain measurement, it can bear simultaneously multidimensional force load and identify radial wheel load by decoupling. The measuring plate can output multichannel voltage signal, usually each channel has the properties of weak signal, strong noise, poor anti-jamming ability. The paper discusses the development of a multichannel data acquisition system for the wheel load measuring plate and conducts the experimental verification, through the data acquisition system achieve time-sharing acquisition of multichannel data, improving the precision and anti-jamming ability of wheel load measurement system.

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Sun, Youwen, Cheng Liu, Pinhua Xie, Andreas Hartl, Kalok Chan, Yuan Tian, Wei Wang, Min Qin, Jianguo Liu und Wenqing Liu. „Industrial SO<sub>2</sub> emission monitoring through a portable multichannel gas analyzer with an optimized retrieval algorithm“. Atmospheric Measurement Techniques 9, Nr. 3 (21.03.2016): 1167–80. http://dx.doi.org/10.5194/amt-9-1167-2016.

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Abstract. SO2 variability over a large concentration range and interferences from other gases have been major limitations in industrial SO2 emission monitoring. This study demonstrates accurate industrial SO2 emission monitoring through a portable multichannel gas analyzer with an optimized retrieval algorithm. The proposed analyzer features a large dynamic measurement range and correction of interferences from other coexisting infrared absorbers such as NO, CO, CO2, NO2, CH4, HC, N2O, and H2O. The multichannel gas analyzer measures 11 different wavelength channels simultaneously to correct several major problems of an infrared gas analyzer including system drift, conflict of sensitivity, interferences among different infrared absorbers, and limitation of measurement range. The optimized algorithm uses a third polynomial instead of a constant factor to quantify gas-to-gas interference. Measurement results show good performance in the linear and nonlinear ranges, thereby solving the problem that the conventional interference correction is restricted by the linearity of the intended and interfering channels. The results imply that the measurement range of the developed multichannel analyzer can be extended to the nonlinear absorption region. The measurement range and accuracy are evaluated through experimental laboratory calibration. Excellent agreement was achieved, with a Pearson correlation coefficient (r2) of 0.99977 with a measurement range from approximately 5 to 10 000 ppmv and a measurement error of less than 2 %. The instrument was also deployed for field measurement. Emissions from three different factories were measured. The emissions of these factories have been characterized by different coexisting infrared absorbers, covering a wide range of concentration levels. We compared our measurements with commercial SO2 analyzers. Overall, good agreement was achieved.

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Da Silva, Marco Jose, Eduardo N. Dos Santos und Tiago P. Vendruscolo. „High-speed multichannel impedance measuring system“. ACTA IMEKO 1, Nr. 1 (07.06.2012): 36. http://dx.doi.org/10.21014/acta_imeko.v1i1.18.

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In this paper, a novel high-speed multichannel impedance measuring system in presented. The measurements are based on simultaneous excitation with two distinct frequencies to interrogate the multiple sensing point of a given sensor. Received signals are analogue-to-digital converted (with a DAQ card) and the amplitudes of each frequency are determined using FFT implemented in LabVIEW. The capacitive and conductive parts of impedance are calculated based on amplitude measurements. The developed system can operate 8 transmitter and 8 receiver electrodes at a frame repetition frequency of up to 781 Hz, i.e. single channels are sampled at 6,248 Hz. The system has been evaluated by measuring reference components. Deviations from references values are below 10% which considering the fast repetition frequency of measurements is satisfactory. The developed system was applied to visualize the fluid distribution over the surface of planar multipoint sensor. Two different liquids (oil and water) and air were evaluated and their spatial distribution over the sensor’s surface was correctly visualized.

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Osaki, Toshihisa, Hiroaki Suzuki, Bruno Le Pioufle und Shoji Takeuchi. „Multichannel Simultaneous Measurements of Single-Molecule Translocation in α-Hemolysin Nanopore Array“. Analytical Chemistry 81, Nr. 24 (15.12.2009): 9866–70. http://dx.doi.org/10.1021/ac901732z.

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Bhargava, Rohit, und Ira W. Levin. „Time-Resolved Fourier Transform Infrared Spectroscopic Imaging“. Applied Spectroscopy 57, Nr. 4 (April 2003): 357–66. http://dx.doi.org/10.1366/00037020360625880.

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Fourier transform infrared (FT-IR) imaging allows simultaneous spectral characterization of large spatial areas due to its multichannel detection advantage. The acquisition of large amounts of data in the multichannel configuration results, however, in a poor temporal resolution of sequentially acquired data sets, which limits the examination of dynamic processes to processes that have characteristic time scales of the order of minutes. Here, we introduce the concept and instrumental details of a time-resolved infrared spectroscopic imaging modality that permits the examination of repetitive dynamic processes whose half-lives are of the order of milliseconds. As an illustration of this implementation of step-scan FT-IR imaging, we examine the molecular responses to external electric-field perturbations of a microscopically heterogeneous polymer–liquid crystal composite. Analysis of the spectroscopic data using conventional univariate and generalized two-dimensional (2D) correlation methods emphasizes an additional capability for accessing of simultaneous spatial and temporal chemical measurements of molecular dynamic processes.

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Li, Xiaoli, Dong Cui, Premysl Jiruska, John E. Fox, Xin Yao und John G. R. Jefferys. „Synchronization Measurement of Multiple Neuronal Populations“. Journal of Neurophysiology 98, Nr. 6 (Dezember 2007): 3341–48. http://dx.doi.org/10.1152/jn.00977.2007.

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The purpose of the present paper is to develop a method, based on equal-time correlation, correlation matrix analysis and surrogate resampling, that is able to quantify and describe properties of synchronization of population neuronal activity recorded simultaneously from multiple sites. Initially, Lorenz-type oscillators were used to model multiple time series with different patterns of synchronization. Eigenvalue and eigenvector decomposition was then applied to identify “clusters” of locally synchronized activity and to calculate a “global synchronization index.” This method was then applied to multichannel data recorded from an in vitro model of epileptic seizures. The results demonstrate that this novel method can be successfully used to analyze synchronization between multiple neuronal population series.

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Kondoh, Jun, Kazuki Saito, Showko Shiokawa und Hideyuki Suzuki. „Simultaneous Measurements of Liquid Properties Using Multichannel Shear Horizontal Surface Acoustic Wave Microsensor“. Japanese Journal of Applied Physics 35, Part 1, No. 5B (30.05.1996): 3093–96. http://dx.doi.org/10.1143/jjap.35.3093.

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Joo, Han Young, Jae Wook Kim, Young Seo Kim, So Yun Jeong, Bongsoo Lee und Joo Hyun Moon. „Development of a Multifunctional Radiation Measurement System for the Rapid Radiological Characterization of a Decommissioned Nuclear Facility Site“. Journal of Sensors 2021 (06.03.2021): 1–12. http://dx.doi.org/10.1155/2021/8870609.

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In this study, a radiation measurement system with multifunctions for the rapid radiological characterization of a decommissioned nuclear facility site was developed and evaluated. The system remotely and simultaneously measures the beta and gamma radiation from the soil at a decommissioned nuclear facility site and wirelessly transmits the measurement data to the main server, which collects and analyzes the data. The radiation-measuring part of the system is composed of a sensing probe, multichannel analyzer (MCA), and laptop computer. The sensing probe is a phoswich radiation sensor (PHORS) consisting of two inorganic scintillators (NaI(Tl) and CaF2(Eu)), each of which simultaneously measures the count rates and energies of the beta and gamma radiation. To test the performance of the PHORS, the beta and gamma radiation from a radiation source at 0–10 cm depths (at steps of 1 cm) under a soil surface was measured. The measurements show that the radiation count rates agree well with the theoretically predicted ones; the PHORS is as good as commercial radiation detectors in providing the energy spectrum of a radionuclide. In addition, a chi-square test was conducted, and the energy resolution was evaluated. The communication part of the system consisting of a global positioning system (GPS) and long-term evolution telecommunication (LTE) modem can successfully transmit the measurement data and their location information.

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Ma, Liuzheng, Zhenfeng Li, Zephania Birech, Shixin Li, Yatao Yang, Wei Zhang und Jiandong Hu. „Multi-Channel Optoelectronic Measurement System for Soil Nutrients Analysis“. Electronics 8, Nr. 4 (20.04.2019): 451. http://dx.doi.org/10.3390/electronics8040451.

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To solve the problems that occur when farmers overuse chemical fertilizers, it is necessary to develop rapid and efficient portable measurement systems for the detection and quantification of nitrogen (N), phosphorus (P), and potassium (K) in soil. Challenges arise from the use of currently available portable instruments which only have a few channels, namely measurement and the reference channels. We report on a home-built, multichannel, optoelectronic measurement system with automatically switching light sources for the detection of N, P, K content in soil samples. This optoelectronic measurement system consists of joint LED light sources with peak emission wavelengths of 405 nm, 660 nm, and 515 nm, a photodiode array, a circuit board with a microcontroller unit (MCU), and a liquid-crystal display (LCD) touch screen. The straightforward principle for rapid detection of the extractable nutrients (N, P, K) was well-established, and characterization of the designed measurement system was done. Using this multi-channel measurement system, available nutrients extracted from six soil samples could be measured simultaneously. The absorbance compensation, concentration calibration, and nutrition measurements were performed automatically to achieve high consistency across six channels. The experimental results showed that the cumulative relative standard deviations of 1.22%, 1.27%, and 1.00% were obtained from six channels with known concentrations of standard solutions, respectively. The coefficients of correlation for the detection of extracted nutrients of N, P, K content in soil samples using both the proposed method and conventional lab-based method were 0.9010, 0.9471, and 0.8923, respectively. Experimental results show that this optoelectronic measurement system can perform the measurement of N, P, K contents of six soil samples simultaneously and may be used as an actual tool in determining nutrients in soil samples with an improvement in detection efficiency.

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Zenevich, Sergei, Iskander Gazizov, Dmitry Churbanov, Yegor Plyashkov, Maxim Spiridonov, Ravil Talipov und Alexander Rodin. „A Concept of 2U Spaceborne Multichannel Heterodyne Spectroradiometer for Greenhouse Gases Remote Sensing“. Remote Sensing 13, Nr. 12 (08.06.2021): 2235. http://dx.doi.org/10.3390/rs13122235.

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We present the project of a 2U CubeSat format spaceborne multichannel laser heterodyne spectroradiometer (MLHS) for studies of the Earth’s atmosphere upper layers in the near-infrared (NIR) spectral range (1258, 1528, and 1640 nm). A spaceborne MLHS operating in the solar occultation mode onboard CubeSat platform, is capable of simultaneous vertical profiling of CO2, H2O, CH4, and O2, as well as Doppler wind measurements, in the tangent heights range of 5–50 km. We considered the low Earth orbit for the MLHS deployment and analyzed the expected surface coverage and spatial resolution during one year of operations. A ground-based prototype of the MLHS for CO2 and CH4 molecular absorption measurements with an ultra-high spectral resolution of 0.0013 cm−1 is presented along with the detailed description of its analytical characteristics and capabilities. Implementation of a multichannel configuration of the heterodyne receiver (four receivers per one spectral channel) provides a significant improvement of the signal-to-noise ratio with the reasonable exposure time typical for observations in the solar occultation mode. Finally, the capability of building up a tomographic picture of sounded gas concentration distributions provided by high spectral resolution is discussed.

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Puluiyo, Juwana, As’ari und Seni H. J. Tongkukut. „Perbandingan Konfigurasi Wenner Alfa, Wenner-Schlumberger, Dipol-dipol Dan Pol-dipol Dalam Metode Geolistrik Tahanan Jenis Untuk Mendeteksi Keberadaan Air Tanah“. Jurnal MIPA 7, Nr. 1 (19.04.2018): 29. http://dx.doi.org/10.35799/jm.7.1.2018.19181.

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Telah dilakukan penelitian untuk mencari konfigurasi yang paling tepat dalam eksplorasi sumber daya air (air tanah) dengan metode geolistrik tahanan jenis konfigurasi Wenner Alfa, Wenner-Schlumberger, Dipol-dipol dan Pol-dipol menggunakan Resistivity meter (multichannel and multielectrode resistivity and IP meter simultaneous channel merek MAE X612-EM). Pengukuran dilakukuan pada 4 lintasan dengan panjang bentangan 96 meter dan pengolahan data menggunggunakan perangkat lunak (softwere) RES2DINV.Hasil penelitian ini menunjukkan bahwa konfigurasi Dipol-dipol adalah konfigurasi yang paling efektif dan efisien dalam mendeteksi keberadaan air tanah dengan karakteristik : waktu eksekusi 24 menit, jumlah data 609 buah, kedalaman 16 meter dan jumlah data pereksekusi 5 titik.Research has been done to find the most appropriate configuration in the exploration of water resources (groundwater) with the geoelectrical Resistivity method of configuration Wenner Alfa, Wenner-Schlumberger, Dipole-dipole and Pole-dipole by using Resistivitymeter (multichannel and multielectric resistivity and IP meter simultaneous channel brand MAE X612-EM). Measurements were performed on 4 line with a stretch length of 96 meters and data processing used software RES2DINV.The results of this study indicate that Dipole-dipole configuration is the most effective and efficient configuration in detecting the presence of groundwater with the characteristics : 24 minutes execution time, 609 pieces of data, 16 meters depth and 5 points of execution data.

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Yappert, M. Cecilia, M. W. Schuyler und J. D. Ingle. „Design and evaluation of a dual multichannel detector spectrometer for simultaneous molecular absorption and luminescence measurements“. Analytical Chemistry 61, Nr. 6 (15.03.1989): 593–600. http://dx.doi.org/10.1021/ac00181a020.

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Solliec, Camille, und Jacky Mary. „Simultaneous measurements of fluctuating pressures using piezoresistive multichannel transducers as applied to atmospheric wind tunnel tests“. Journal of Wind Engineering and Industrial Aerodynamics 56, Nr. 1 (April 1995): 71–86. http://dx.doi.org/10.1016/0167-6105(94)00013-4.

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Prevost, Paoline, Kristel Chanard, Luce Fleitout, Eric Calais, Damian Walwer, Tonie van Dam und Michael Ghil. „Data-adaptive spatio-temporal filtering of GRACE data“. Geophysical Journal International 219, Nr. 3 (19.09.2019): 2034–55. http://dx.doi.org/10.1093/gji/ggz409.

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SUMMARY Measurements of the spatio-temporal variations of Earth’s gravity field from the Gravity Recovery and Climate Experiment (GRACE) mission have led to new insights into large spatial mass redistribution at secular, seasonal and subseasonal timescales. GRACE solutions from various processing centres, while adopting different processing strategies, result in rather coherent estimates. However, these solutions also exhibit random as well as systematic errors, with specific spatial patterns in the latter. In order to dampen the noise and enhance the geophysical signals in the GRACE data, we propose an approach based on a data-driven spatio-temporal filter, namely the Multichannel Singular Spectrum Analysis (M-SSA). M-SSA is a data-adaptive, multivariate, and non-parametric method that simultaneously exploits the spatial and temporal correlations of geophysical fields to extract common modes of variability. We perform an M-SSA analysis on 13 yr of GRACE spherical harmonics solutions from five different processing centres in a simultaneous setup. We show that the method allows us to extract common modes of variability between solutions, while removing solution-specific spatio-temporal errors that arise from the processing strategies. In particular, the method efficiently filters out the spurious north–south stripes, which are caused in all likelihood by aliasing, due to the imperfect geophysical correction models and low-frequency noise in measurements. Comparison of the M-SSA GRACE solution with mass concentration (mascons) solutions shows that, while the former remains noisier, it does retrieve geophysical signals masked by the mascons regularization procedure.

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Pan, Yuangang, Ivor W. Tsang, Avinash K. Singh, Chin-Teng Lin und Masashi Sugiyama. „Stochastic Multichannel Ranking with Brain Dynamics Preferences“. Neural Computation 32, Nr. 8 (August 2020): 1499–530. http://dx.doi.org/10.1162/neco_a_01293.

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A driver's cognitive state of mental fatigue significantly affects his or her driving performance and more important, public safety. Previous studies have leveraged reaction time (RT) as the metric for mental fatigue and aim at estimating the exact value of RT using electroencephalogram (EEG) signals within a regression model. However, due to the easily corrupted and also nonsmooth properties of RTs during data collection, methods focusing on predicting the exact value of a noisy measurement, RT generally suffer from poor generalization performance. Considering that human RT is the reflection of brain dynamics preference (BDP) rather than a single regression output of EEG signals, we propose a novel channel-reliability-aware ranking (CArank) model for the multichannel ranking problem. CArank learns from BDPs using EEG data robustly and aims at preserving the ordering corresponding to RTs. In particular, we introduce a transition matrix to characterize the reliability of each channel used in the EEG data, which helps in learning with BDPs only from informative EEG channels. To handle large-scale EEG signals, we propose a stochastic-generalized expectation maximum (SGEM) algorithm to update CArank in an online fashion. Comprehensive empirical analysis on EEG signals from 40 participants shows that our CArank achieves substantial improvements in reliability while simultaneously detecting noisy or less informative EEG channels.

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Zhang, Li, Charles B. Theurer, Robert X. Gao und David O. Kazmer. „Analytic Wavelet-Based Ultrasonic Pulse Differentiation for Injection Mold Cavity Pressure Measurement“. Journal of Manufacturing Science and Engineering 128, Nr. 1 (20.07.2005): 370–74. http://dx.doi.org/10.1115/1.2123048.

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A new signal-processing technique based on analytic wavelet transform has been developed for detecting and differentiating temporally overlapped ultrasonic pulse trains that carry spatially distributed pressure information across an injection mold cavity. Compared to conventional wavelets that have a constant relative bandwidth at all the scales, the analytic wavelets investigated in this paper feature variable relative bandwidth, making it possible to simultaneously match the frequency characteristics of the ultrasonic pulse trains transmitted from the mold-embedded pressure sensors. As a result, more accurate detection and differentiation of the temporal and spectral information embedded within the ultrasonic pulse trains could be achieved. Theoretical framework for the analytic wavelet transform was established, and a multichannel ultrasonic pulse detector based on the complex Morlet wavelet was designed and experimentally investigated. The results have confirmed the effectiveness of the new signal-processing technique for on-line pressure sensing for injection molding process monitoring.

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TCHEREMISKINE, V. I., M. L. SENTIS, M. P. SABONNADIERE und L. D. MIKHEEV. „A POWERFUL SOURCE OF BROADBAND VUV RADIATION BASED ON A MULTICHANNEL SLIDING DISCHARGE“. Surface Review and Letters 09, Nr. 01 (Februar 2002): 645–49. http://dx.doi.org/10.1142/s0218625x02002786.

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A powerful source of broadband UV-VUV radiation is developed on the base of a multichannel sliding discharge. The discharge having a radiating surface of hundreds of cm 2 is initiated simultaneously along several dozens of parallel linear channels located close to each other. The design of the discharge electric circuit allows a remarkably fast energy deposition into plasma: up to 4 kJ during 1.5 μs. Absolute measurements of discharge VUV radiation are performed by the method of spectrally selective dynamic actinometry. The total photon flux produced by the source within the spectral range of 120–200 nm reaches 1026 photons/s.

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Masui, Daisuke, Suguru Fukahori, Naoki Hashizume, Shinji Ishii, Naruki Higashidate, Saki Sakamoto, Shiori Tsuruhisa et al. „Simultaneous Evaluation of Laryngopharyngeal Reflux and Swallowing Function Using Hypopharyngeal Multichannel Intraluminal Impedance Measurements in Neurologically Impaired Patients“. Journal of Neurogastroenterology and Motility 27, Nr. 2 (30.04.2021): 198–204. http://dx.doi.org/10.5056/jnm20125.

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Pérez-Bailón, Jorge, Belén Calvo und Nicolás Medrano. „A CMOS Low Pass Filter for SoC Lock-in-Based Measurement Devices“. Sensors 19, Nr. 23 (26.11.2019): 5173. http://dx.doi.org/10.3390/s19235173.

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This paper presents a fully integrated Gm–C low pass filter (LPF) based on a current steering Gm reduction-tuning technique, specifically designed to operate as the output stage of a SoC lock-in amplifier. To validate this proposal, a first-order and a second-order single-ended topology were integrated into a 1.8 V to 0.18 µm CMOS (Complementary Metal-Oxide-Semiconductor) process, showing experimentally a tuneable cutoff frequency that spanned five orders of magnitude, from tens of mHz to kHz, with a constant current consumption (below 3 µA/pole), compact size (<0.0140 mm2/pole), and a dynamic range better than 70 dB. Compared to state-of-the-art solutions, the proposed approach exhibited very competitive performances while simultaneously fully satisfying the demanding requirements of on-chip portable measurement systems in terms of highly efficient area and power. This is of special relevance, taking into account the current trend towards multichannel instruments to process sensor arrays, as the total area and power consumption will be proportional to the number of channels.

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Kanicky, Viktor, Ivan Novotny, Jan Musil und Jean-Michel Mermet. „Depth Profiling of Thick Layers of Graded Metal—Zirconia Ceramic Coatings Using Laser Ablation Inductively Coupled Plasma Atomic Emission Spectrometry“. Applied Spectroscopy 51, Nr. 7 (Juli 1997): 1042–46. http://dx.doi.org/10.1366/0003702971941467.

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The feasibility of depth profiling of thick layers (>100 μm) consisting of partially stabilized zirconia coating and graded metal—ceramic coating on Inconel steel (ZrO2–Y2O3/NiCrAlY/steel and ZrO2–CeO2/NiCrAlY/steel) was studied on the basis of the use of laser ablation inductively coupled plasma atomic emission spectrometry (LA-ICP-AES). An ICP spectrometer equipped with a multichannel detection was used for the simultaneous measurements of the line intensities. The ablation was performed with a Nd:YAG laser operated in a Q-switched mode at 266 nm. To study the erosion rate, we used either a static or a translation mode for the ablation, and the corresponding temporal behavior of the signals was studied. A higher erosion rate was found for the translation mode when depths higher than several hundred micrometers were probed.

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Neuschwander, Klaus, Jochen Moll, Vittorio Memmolo, Matthias Schmidt und Marcel Bücker. „Simultaneous load and structural monitoring of a carbon fiber rudder stock: Experimental results from a quasi-static tensile test“. Journal of Intelligent Material Systems and Structures 30, Nr. 2 (06.11.2018): 272–82. http://dx.doi.org/10.1177/1045389x18806392.

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Carbon-fiber-reinforced plastics are widely used in lightweight marine structures due to their high strength and superior fatigue behavior. In this article, we will present an innovative methodology for simultaneous load and structural monitoring of a carbon-fiber-reinforced plastic rudder stock as part of a big commercial vessel. Experimental results are presented here from a quasi-static tensile test in which the load monitoring is performed using embedded strain sensors. Structural monitoring is based on high-frequency electromechanical impedance spectroscopy combined with dedicated signal processing and surface-mounted piezoelectric transducers. We have achieved the following results: (1) the demonstration of a hybrid monitoring system including load and structural monitoring, (2) successful embedding of strain gauges during composite manufacturing of the carbon-fiber-reinforced plastic rudder stock, (3) development of instrumentation hardware for multichannel electromechanical impedance measurements, and (4) successful damage detection by means of electromechanical impedance spectroscopy in thick carbon-fiber-reinforced plastic rudder stock samples exploiting strain data.

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Utiya, Jefriyanto, As’ari As’ari und Seni HJ Tongkukut. „METODE GEOLISTRIK RESTIVITAS KONFIGURASI WENNER-SCHLUMBERGER DAN KONFIGURASI DIPOLE-DIPOLE UNTUK IDENTIFIKASI PATAHAN MANADO DI KECAMATAN PAALDUA KOTA MANADO“. JURNAL ILMIAH SAINS 17, Nr. 1 (10.11.2015): 135. http://dx.doi.org/10.35799/jis.15.2.2015.10228.

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METODE GEOLISTRIK RESTIVITAS KONFIGURASI WENNER-SCHLUMBERGER DAN KONFIGURASI DIPOLE-DIPOLE UNTUK IDENTIFIKASI PATAHAN MANADO DI KECAMATAN PAALDUA KOTA MANADO ABSTRAK Telah dilakukan penelitian untuk mendeteksi keberadaan Patahan Manado di Jalan Ringroad, Kelurahan Malendeng, Kecamatan Paaldua, Kota Manado, menggunakan metode geolistrik tahanan jenis konfigurasi Wenner-Schlumberger dan konfigurasi Dipole-dipole. Akuisisi data menggunakan multichannel and multielectrode resistivity and IP meter 46 simultaneous channel merek MAE X612-EM. Pengukuran dilakukan pada 4 lintasan dengan panjang masing-masing lintasan 480 meter. Pengolahan data dilakukan dengan menggunakan perangkat lunak RES2DINV dengan hasil berupa citra resistivitas bawah permukaan 2D. Diperoleh hasil bahwa bidang-bidang lemah pada lintasan 2 dan lintasan 4 dengan nilai resitivitas batuan berkisar (2,72-86) Ωm, memotong perlapisan antara batuan yang memiliki resistivitas yang lebih tinggi. Bidang lemah tersebut diperkirakan sebagai rekahan yang ditemukan pada kedalaman (2,50-40) meter dari permukaan tanah. Kata Kunci : Wenner-Schlumberger, Dipole-dipole, RES2DINV, Patahan Manado. GEOELECTRIC RESISTIVITY METHOD WITH WENNER-SCHLUMBERGER AND DIPOLE-DIPOLE CONFIGURATIONS FOR IDENTIFICATION MANADO FAULT IN MANADO AT PAALDUA DISTRICTS ABSTRACT The research about detecting the presence of Manado Fault in Manado, Malendeng Village, Paaldua District, by using resistivity geoelectric method with Wenner-Schlumberger and Dipole-dipole configurations, has been done. Multichannel and multielectrode resistivity and IP meters 46 simultaneous channels MAE brand X612-EM is device for acquisition of data. The Measurements were taken on four tracks with each length of track is 480 meters. The data processing was performed with RES2DINV software that results 2D image subsurface resistivity. The results indicate that the weak areas on the track 2 and track 4 with range value of rock resitivitas is 2.72 Ωm to till 86 Ωm , cut the bedding between rocks which have higher resistivity. The weak areas is estimated as the fracture on the depth (2.50 to 40) meters from the ground. Keywords: Wenner-Schlumberger, Dipole-dipole, RES2DINV, Fault Manado.

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Oishi, Haruki, Yasumichi Hatayama, Masaji Fusamoto und Yoshitsugu Sakata. „Development of a Multichannel Turbidimetric-Kinetic Photometer for the Quantitative Determination of Endotoxin“. Applied Spectroscopy 43, Nr. 5 (Juli 1989): 821–26. http://dx.doi.org/10.1366/0003702894202319.

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A turbidimetric-kinetic photometer which monitors 64 samples simultaneously and independently has been developed for the automated measurement of endotoxin. This instrument measures the turbidity change at 660 nm in a gelation reaction of the LAL/endotoxin system and automatically scores the reaction time required to obtain a certain turbidity change as gelation time. Since a stationary dry bath incubator controls the reaction temperature of the samples at 37 ± 0.5°C and also controls the ambience of the optical system assembled into the incubator, the objective detection of gelation is provided without any disturbance from sample vibration, and the drift of the detection system is minimized. An extremely wide range for the calibration curve, such as 4 or 5 orders of magnitude of endotoxin concentration, is obtained without sample dilution. The coefficients of variation of the calculated endotoxin concentration are 4.91 to 14.0%.

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Piechowicz, Janusz, und Ireneusz Czajka. „Estimation of Acoustic Impedance for Surfaces Delimiting the Volume of an Enclosed Space“. Archives of Acoustics 37, Nr. 1 (01.03.2012): 97–102. http://dx.doi.org/10.2478/v10168-012-0013-8.

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AbstractSeveral methods can be applied for analyses of the acoustic field in enclosed rooms namely: wave propagation, geometrical or statistical analysis. The paper presents problems related to application of the boundary elements method to modelling of acoustic field parameters. Experimental and numerical studies have been combined for evaluation of acoustic impedance of the material used for the walls of a model room. The experimental studies have been carried out by implementing a multichannel measuring system inside the constructed model of an industrial room. The measuring system allowed simultaneous measurements of the source parameters - the loudspeaker membrane vibration speed, the acoustic pressure values in reception points located inside the model space as well as phase shifts between signals registered in various reception points. The numerical modelling making use of the acoustic pressure values measured inside the analyzed space allowed determination of requested parameters of the surface at the space boundary.

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Okajima, Hajime, und Hiro-O. Hamaguchi. „Fast Low Frequency (Down to 10 cm−1) Multichannel Raman Spectroscopy Using an Iodine Vapor Filter“. Applied Spectroscopy 63, Nr. 8 (August 2009): 958–60. http://dx.doi.org/10.1366/000370209788964368.

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We have constructed a multi-channel Raman spectrometer that is capable of recording the low frequency region down to 5 cm−1 with a measurement time of a few tenths of a second. An iodine vapor filter, which uses a narrow (∼0.03 cm−1) absorption line of iodine for Rayleigh scattering elimination, is combined with a multi-channel Raman spectrometer composed of a single polychromator and a charge-coupled device (CCD) camera. Thanks to the high Rayleigh scattering elimination efficiency of the filter, which is over 106, Raman spectra of microcrystalline l-cystine from −300 cm−1 to 1000 cm−1 are simultaneously measurable with a small gap of 10 cm−1 (–5 cm−1 to 5 cm−1). Although raw spectra contain many sharp spikes due to the fine structures of iodine absorption, they can be correctly compensated with the use of a transmittance spectrum measured under the same experimental conditions. Many Raman bands including the 9.8 cm−1 band are measured with a high signal-to-noise ratio in both the Stokes and anti-Stokes sides with a measurement time as short as 0.2 s.

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50

Sidorov, Igor Alexandrovich, Alexsandr Grigorevich Gudkov, Vitalij Yurievich Leushin, Eugenia Nikolaevna Gorlacheva, Eugenij Pavlovich Novichikhin und Svetlana Victorovna Agasieva. „Measurement and 3D Visualization of the Human Internal Heat Field by Means of Microwave Radiometry“. Sensors 21, Nr. 12 (10.06.2021): 4005. http://dx.doi.org/10.3390/s21124005.

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The possibility of non-invasive determination of the depth of the location and temperature of a cancer tumor in the human body by multi-frequency three-dimensional (3D) radiothermography is considered. The models describing the receiving of the human body’s own radiothermal field processes are presented. The analysis of the possibility of calculating the desired parameters based on the results of measuring antenna temperatures simultaneously in two different frequency ranges is performed. Methods of displaying on the monitor screen the three-dimensional temperature distribution of the subcutaneous layer of the human body, obtained as a result of data processing of a multi-frequency multichannel radiothermograph, are considered. The possibility of more accurate localization of hyperthermia focus caused by the presence of malignant tumors in the depth of the human body with multi-frequency volumetric radiothermography is shown. The results of the study of various methods of data interpolation for displaying the continuous intrinsic radiothermal field of the human body are presented. Examples of displaying the volumetric temperature distribution by the moving plane method based on digital models and the results of an experimental study of the thermal field of the human body and head are given.

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