Статті в журналах: "Pulse arrival time"

1

Ho, K. C. "Pulse arrival time estimation based on pulse sample ratios." IEE Proceedings - Radar, Sonar and Navigation 142, no. 4 (1995): 153. http://dx.doi.org/10.1049/ip-rsn:19951987.

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2

Jindal, GhanshyamD, ChaitaliA Deshmukh, UttamR Bagal, and GajananD Nagare. "Pulse arrival time: Measurement and clinical applications." MGM Journal of Medical Sciences 9, no. 1 (2022): 103. http://dx.doi.org/10.4103/mgmj.mgmj_23_22.

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3

Deshpande, A. A., and P. M. McCulloch. "Periodic Changes in Intensity and Arrival Time of Pulses from the Vela Pulsar: Evidence for Free Precession?" International Astronomical Union Colloquium 160 (1996): 101–2. http://dx.doi.org/10.1017/s0252921100041130.

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We present dual-frequency measurements on the Vela pulsar with a view to study the slow variations in the pulsed flux and the apparent differences in the pulse arrival times. We examine the data for correlated variations between the pulse intensities and arrival times at the two frequencies and discuss two main possibilities in order to explain the observed behaviour.The data presented here consists of a) Pulse intensities, S635& S950, at S635& S950MHz respectively and b) the ‘residual’ differences in the time of arrival of the pulse at the lower frequency, ΔTOA, with respect to that at the higher frequency. These data, over a span of ~1300 days (during 1988-92), were obtained as a part of the routine monitoring of the Vela pulsar from Mt. Pleasant Observatory of University of Tasmania, Hobart (see McCullochet al. 1990).

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4

Stark, M. J., A. Baykal, T. Strohmayer, and J. H. Swank. "Pulse Arrival Time Glitches in GRO J1744−28." Astrophysical Journal 470, no. 2 (October 20, 1996): L109—L112. http://dx.doi.org/10.1086/310311.

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5

Rodin, A. E., V. V. Oreshko, and V. A. Fedorova. "Comparison of Terrestrial and Lunar Time Scales by Giant Pulsar Impulses." Astronomy Reports 65, no. 11 (November 2021): 1136–44. http://dx.doi.org/10.1134/s1063772921110068.

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Abstract We have developed a model for the time delay of pulse arrival between stations on the Moon and Earth. Comparison of the lunar and terrestrial time scales is proposed to be carried out by comparing the arrival time moments of giant pulses from pulsars. A method for such a comparison has been developed based on the cross-correlation analysis of the received pulses. Using the example of giant pulses from the pulsar PSR 0531+21, we showed that the error of comparing scales in the case of a high signal-to-noise ratio reaches a sub-discrete level and, thus, is determined by the reception band of the recording equipment.

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6

Tarng, J. H., L. K. Wang, C. C. Yang, and S. T. McDaniel. "Arrival time and pulse width of acoustic pulses in a turbulent ocean." Journal of the Acoustical Society of America 84, no. 5 (November 1988): 1802–7. http://dx.doi.org/10.1121/1.397146.

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7

Kim, Dohyun, Jong-Hoon Ahn, Jongshill Lee, Hoon Ki Park, and In Young Kim. "A Linear Transformation Approach for Estimating Pulse Arrival Time." Journal of Applied Mathematics 2012 (2012): 1–12. http://dx.doi.org/10.1155/2012/643653.

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We propose a new mathematical framework for estimating pulse arrival time (PAT). Existing methods of estimating PAT rely on local characteristic points or global parametric models: local characteristic point methods detect points such as foot points, max points, or max slope points, while global parametric methods fit a parametric form to the anacrotic phase of pulse signals. Each approach has its strengths and weaknesses; we take advantage of the favorable properties of both approaches in our method. To be more precise, we transform continuous pulse signals into scalar timing codes through three consecutive transformations, the last of which is a linear transformation. By training the linear transformation method on a subset of data, the proposed method yields results that are robust to noise. We apply this method to real photoplethysmography (PPG) signals and analyze the agreement between our results and those obtained using a conventional approach.

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8

Loboiko, B. I., and O. B. Borodkina. "Determination of the pulse arrival time in a local time scale." Measurement Techniques 33, no. 1 (January 1990): 47–50. http://dx.doi.org/10.1007/bf00866817.

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9

Malofeev, V. M., and O. I. Malov. "Mean, individual pulses and spectrum of Geminga radio emission." International Astronomical Union Colloquium 177 (2000): 241–42. http://dx.doi.org/10.1017/s0252921100059583.

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AbstractThe measurements of profiles at 102, 87, 59 and 40 MHz are presented. Geminga shows unique character of radio emission: the most steep spectrum, the large changes of pulse widths, phases of pulse time of arrival and the presence of giant pulses.

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10

Yoon, Young-Zoon, Jae Min Kang, Yongjoo Kwon, Sangyun Park, Seungwoo Noh, Younho Kim, Jongae Park, and Sung Woo Hwang. "Cuff-Less Blood Pressure Estimation Using Pulse Waveform Analysis and Pulse Arrival Time." IEEE Journal of Biomedical and Health Informatics 22, no. 4 (July 2018): 1068–74. http://dx.doi.org/10.1109/jbhi.2017.2714674.

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11

Solà, Josep, Rolf Vetter, Philippe Renevey, Olivier Chételat, Claudio Sartori, and Stefano F. Rimoldi. "Parametric estimation of pulse arrival time: a robust approach to pulse wave velocity." Physiological Measurement 30, no. 7 (June 3, 2009): 603–15. http://dx.doi.org/10.1088/0967-3334/30/7/006.

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12

van Duijvenboden, Stefan, Ben Hanson, Nick Child, Pier D. Lambiase, Christopher A. Rinaldi, Gill Jaswinder, Peter Taggart, and Michele Orini. "Pulse Arrival Time and Pulse Interval as Accurate Markers to Detect Mechanical Alternans." Annals of Biomedical Engineering 47, no. 5 (February 12, 2019): 1291–99. http://dx.doi.org/10.1007/s10439-019-02221-4.

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13

Wan Zaki, W. S., R. Correia, S. Korposh, B. R. Hayes-Gill, and S. P. Morgan. "A Comparative Study on Instantaneous and Mean Pulse Arrival Time for Cuffless Blood Pressure Estimation." Journal of Physics: Conference Series 2071, no. 1 (October 1, 2021): 012028. http://dx.doi.org/10.1088/1742-6596/2071/1/012028.

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Abstract Pulse arrival time (PAT) is the delay time between the peak of the R-wave Electrocardiogram (ECG) signal and the peak of Photoplethysmogram (PPG) signals. This method is widely exploited for continuous cuffless blood pressure measurement. In the literature, the PAT was determined based on the mean at a certain number or certain period of heartbeats, but none of them deployed a single pulse wave for PAT calculation. Therefore, in this paper, a relationship between mean PAT (15 pulses ± Standard Deviation (SD)) and instantaneous PAT (a pulse) with blood pressure (BP) was investigated on thirteen healthy male volunteers (aged between 17 to 42 years) through a pedal exercise. The PAT is grouped into three (3) categories which depend on the spatial position of the PPG signal measured; finger (PATf), wrist (PATw), and underfoot (PATt). The ECG and the PPG signals were synchronized using a Nexus-10 MK II data acquisition device and Matlab software (R 2014b) for subsequent analysis. An oscillometric cuff-based blood pressure instrument (Ostar, P2) was used as a BP reference during the experiment. Statistical analysis showed no significant difference in the |r| value between mean (15 pulses ± SD) and instantaneous PAT-BP; hence both methods are applicable for BP estimation using the PAT-BP calibration technique.

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14

Tsai, Bin-Ming, and Chester S. Gardner. "Time-resolved speckle effects on the estimation of laser-pulse arrival times." Journal of the Optical Society of America A 2, no. 5 (May 1, 1985): 649. http://dx.doi.org/10.1364/josaa.2.000649.

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15

Ivanov, Rosen, Jia Liu, Günter Brenner, Maciej Brachmanski, and Stefan Düsterer. "FLASH free-electron laser single-shot temporal diagnostic: terahertz-field-driven streaking." Journal of Synchrotron Radiation 25, no. 1 (January 1, 2018): 26–31. http://dx.doi.org/10.1107/s160057751701253x.

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The commissioning of a terahertz-field-driven streak camera installed at the free-electron laser (FEL) FLASH at DESY in Hamburg, being able to deliver photon pulse duration as well as arrival time information with ∼10 fs resolution for each single XUV FEL pulse, is reported. Pulse durations between 300 fs and <15 fs have been measured for different FLASH FEL settings. A comparison between the XUV pulse arrival time and the FEL electron bunch arrival time measured at the FLASH linac section exhibits a correlation width of 20 fs r.m.s., thus demonstrating the excellent operation stability of FLASH. In addition, the terahertz-streaking setup was operated simultaneously to an alternative method to determine the FEL pulse duration based on spectral analysis. FLASH pulse duration derived from simple spectral analysis is in good agreement with that from terahertz-streaking measurement.

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16

Heimark, Sondre, Ole Marius Hoel Rindal, Trine Seeberg, Alexey Stepanov, Elin Sundby Boysen, Camilla Lund Søraas, Aud Eldrid Stenehjem, Fadl Elmula Mohamed Fadl Elmula, and Bård Waldum-Grevbo. "PULSE ARRIVAL TIME CAN TRACK CHANGES IN SYSTOLIC BLOOD PRESSURE." Journal of Hypertension 39, Supplement 1 (April 2021): e132. http://dx.doi.org/10.1097/01.hjh.0000745808.43316.c3.

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17

Heimark, Sondre, Ole Marius H. Rindal, Trine M. Seeberg, Alexey Stepanov, Elin S. Boysen, Kasper G. Bøtker-Rasmussen, Nina K. Mobæk, et al. "Blood pressure altering method affects correlation with pulse arrival time." Blood Pressure Monitoring 27, no. 2 (December 1, 2021): 139–46. http://dx.doi.org/10.1097/mbp.0000000000000577.

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18

Wang, J., G. M. Shaifullah, J. P. W. Verbiest, C. Tiburzi, D. J. Champion, I. Cognard, M. Gaikwad, et al. "A comparative analysis of pulse time-of-arrival creation methods." Astronomy & Astrophysics 658 (February 2022): A181. http://dx.doi.org/10.1051/0004-6361/202141121.

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Context. Extracting precise pulse times of arrival (TOAs) and their uncertainties is the first and most fundamental step in high-precision pulsar timing. In the classical method, TOAs are derived from total intensity pulse profiles of pulsars via cross-correlation with an idealised 1D template of that profile. While a number of results have been presented in the literature that rely on the ever increasing sensitivity of these pulsar timing experiments, there is no consensus on the most reliable methods for creating TOAs, and, more importantly, on the associated TOA uncertainties for each scheme. Aims. We present a comprehensive comparison of TOA determination practices. We focus on creating timing templates, TOA determination methods, and the most useful TOA bandwidth. The aim is to present a possible approach towards TOA optimisation, the (partial) identification of an optimal TOA-creation scheme, and the demonstration of optimisation differences between pulsars and data sets. Methods. We compared the values of data-derived template profiles with analytic profiles and evaluated the three most commonly used template-matching methods. Finally, we studied the relation between timing precision and TOA bandwidth to identify any potential breaks in this relation. As a practical demonstration, we applied our selected methods to European Pulsar Timing Array data on three test pulsars, PSRs J0218+4232, J1713+0747, and J2145−0750. Results. Our demonstration shows that data-derived and smoothed templates are typically preferred to some more commonly applied alternatives. The template-matching method called Fourier domain with Markov chain Monte Carlo is generally superior to or competitive with other methods. While the optimal TOA bandwidth is strongly dependent on pulsar brightness, telescope sensitivity, and scintillation properties, some significant frequency averaging seems required for the data we investigated.

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19

Basano, L., and P. Ottonello. "Randomization of the start pulse in time‐of‐arrival correlators." Review of Scientific Instruments 60, no. 4 (April 1989): 634–37. http://dx.doi.org/10.1063/1.1140375.

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20

Ahn, C. C., and O. L. Krivanek. "Excited State Lifetime Measurement By EEL-CL Coincidence." Proceedings, annual meeting, Electron Microscopy Society of America 43 (August 1985): 406–7. http://dx.doi.org/10.1017/s0424820100118904.

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The lifetime of an excited state can be measured by detecting both the excitation (by EELS) and the de-excitation (by catho- doluminescence), and measuring the delay between the two events. We have adapted this technique for the measurement of lifetimes in an electron microscope.The experimental set-up is shown in Fig. 1. The arrival time and the energy loss of single electrons is monitored by the EELS (Gatan 607), and the arrival time and wavelength of single photons is monitored by the CL spectrometer. Pulses corresponding to the two events are fed to a time-to-amplitude converter (TAC), which outputs a variable height pulse proportional to the delay between the events. If no second (stop) pulse is detected within a preset time interval, the TAC recognizes a “false start”, does not output anything, and starts looking for a “start” pulse again. Since the count rate in the CL channel was typically 10 to 100 times weaker than in the EEL channel, we minimized the false starts by using the CL signal as the start pulse and the EEL signal, suitably delayed, as the stop pulse. This yields a “reversed time” spectrum, but minimizes the dead time of the electronics.

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21

Ma, Shuang, Zheng Liu, and Wen Li Jiang. "Pulse Sorting Algorithm Using TDOA in Multiple Sensors System." Advanced Materials Research 571 (September 2012): 665–70. http://dx.doi.org/10.4028/www.scientific.net/amr.571.665.

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Time difference of arrival (TDOA) can be used for pulse sorting. To solve the problem of deceptive TDOA clusters caused by high pulse repetitive frequency (PRF) emitters and the problem of less pulse accumulation caused by ultra-low PRF emitters, a recursive extended histogram (REH) algorithm is proposed. TDOA data are formed into an extended histogram structure, which is processed recursively to detect and sort out the pulses of each emitter. Simulation results show that the method is applicable and effective.

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22

BOREJKO, PIOTR, CHI-FANG CHEN, and YIH-HSING PAO. "APPLICATION OF THE METHOD OF GENERALIZED RAYS TO ACOUSTIC WAVES IN A LIQUID WEDGE OVER ELASTIC BOTTOM." Journal of Computational Acoustics 09, no. 01 (March 2001): 41–68. http://dx.doi.org/10.1142/s0218396x01000462.

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A range-dependent problem of shallow water acoustics is modeled by a liquid wedge over fast-speed elastic substratum, and the solution is derived based on the method of generalized rays, where the total acoustic field is decomposed into a sum of partial waves, comprising the wave emitted from the point source and the multi-reflected waves. The contribution of each partial wave at a given time is represented by a single integral. The diffracted waves arising from scattering at the apex of the wedge are neglected in this otherwise exact solution. The pressure records are evaluated at the downslope receiver when the pressure pulse applied at a point situated within the wedge has impulsive or harmonic time history. It was found that the arrival of the source pulse is preceded by the group of head wave arrivals, and this early portion of the record (the ground wave) includes considerable pressure build-ups. For a Heaviside source-pulse, we have found that the pressure records of the partial waves exhibit a singular behavior such as the logarithmic singularity at the arrival time of the totally reflected spherical wave. This singular behavior was not found for less sharp input, that is, a triangular source-pulse. We have also found that for a causal harmonic input of lower frequency the ground wave stands out very clearly, whereas for that of higher frequency it is almost suppressed, and for both frequencies the response becomes more or less steady-state soon after the arrival of a few partial waves.

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23

Owada, Shigeki, Mizuho Fushitani, Akitaka Matsuda, Hikaru Fujise, Yuuma Sasaki, Yasumasa Hikosaka, Akiyoshi Hishikawa, and Makina Yabashi. "Characterization of soft X-ray FEL pulse duration with two-color photoelectron spectroscopy." Journal of Synchrotron Radiation 27, no. 5 (August 6, 2020): 1362–65. http://dx.doi.org/10.1107/s1600577520008516.

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The pulse duration of soft X-ray free-electron laser (FEL) pulses of SACLA BL1 (0.2–0.3 nC per bunch, 0.5–0.8 MeV) were characterized by photoelectron sideband measurements. The intensity of the He 1 s−1 photoelectron sidebands generated by a near-infrared femtosecond laser was measured as a function of the time delay between the two pulses using an arrival time monitor. From the width of the cross-correlation trace thus derived, the FEL pulse duration was evaluated to be 28 ± 5 fs full width at half-maximum in the photon energy range between 40 eV and 120 eV.

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24

Zhang, Guanqun, Mingwu Gao, Da Xu, N. Bari Olivier, and Ramakrishna Mukkamala. "Pulse arrival time is not an adequate surrogate for pulse transit time as a marker of blood pressure." Journal of Applied Physiology 111, no. 6 (December 2011): 1681–86. http://dx.doi.org/10.1152/japplphysiol.00980.2011.

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Pulse transit time (PTT) is a proven, simple to measure, marker of blood pressure (BP) that could potentially permit continuous, noninvasive, and cuff-less BP monitoring (after an initial calibration). However, pulse arrival time (PAT), which is equal to the sum of PTT and the pre-ejection period, is gaining popularity for BP tracking, because it is even simpler to measure. The aim of this study was to evaluate the hypothesis that PAT is an adequate surrogate for PTT as a marker of BP. PAT and PTT were estimated through the aorta using high-fidelity invasive arterial waveforms obtained from six dogs during wide BP changes induced by multiple interventions. These time delays and their reciprocals were evaluated in terms of their ability to predict diastolic, mean, and systolic BP (DBP, MBP, and SBP) per animal. The root mean squared error (RMSE) between the BP parameter predicted via the time delay and the measured BP parameter was specifically used as the evaluation metric. Taking the reciprocals of the time delays tended to reduce the RMSE values. The DBP, MBP, and SBP RMSE values for 1/PAT were 9.8 ± 5.2, 10.4 ± 5.6, and 11.9 ± 6.1 mmHg, whereas the corresponding values for 1/PTT were 5.3 ± 1.2, 4.8 ± 1.0, and 7.5 ± 2.2 mmHg ( P < 0.05). Thus tracking BP via PAT was not only markedly worse than via PTT but also unable to meet the FDA BP error limits. In contrast to previous studies, our results quantitatively indicate that PAT is not an adequate surrogate for PTT in terms of detecting challenging BP changes.

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25

Gong Fengxun, 宫峰勋, and 曹雅茹 Cao Yaru. "Analysis of Time of Arrival Accuracy Based on Preamble Pulse Signals." Laser & Optoelectronics Progress 57, no. 21 (2020): 210704. http://dx.doi.org/10.3788/lop57.210704.

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26

Bote, José M., Joaquín Recas, and Román Hermida. "Evaluation of blood pressure estimation models based on pulse arrival time." Computers & Electrical Engineering 84 (June 2020): 106616. http://dx.doi.org/10.1016/j.compeleceng.2020.106616.

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27

Liu, Yan, and Fucheng Guo. "Fast TDOA and FDOA Estimation for Coherent Pulse Signals." International Journal of Antennas and Propagation 2022 (September 20, 2022): 1–9. http://dx.doi.org/10.1155/2022/5390970.

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Time difference of arrival (TDOA) and frequency difference of arrival (FDOA) have been widely used for localizing temporally continuous signals passively. Temporal sparsity of pulse signals makes their TDOA and FDOA estimation processes much different, and computational complexity is a major concern in this area. This paper addresses the problem of fast TDOA and FDOA estimation of pulse signals and focuses mainly on narrowband coherent pulses. By decoupling the effects of TDOA and FDOA in the cost function of localization approximately, we propose a fast coarse TDOA and FDOA estimation method. The estimates are then refined with the cross-ambiguity function (CAF) algorithm within a small TDOA and FDOA neighborhood. In the simulations, the proposed method is demonstrated to have satisfying TDOA and FDOA estimation precisions, and it exceeds existing counterparts largely in computational efficiency.

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28

Morhart, C., and E. M. Biebl. "High resolution time of arrival estimation for a cooperative sensor system." Advances in Radio Science 8 (September 30, 2010): 61–66. http://dx.doi.org/10.5194/ars-8-61-2010.

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Abstract. Distance resolution of cooperative sensors is limited by the signal bandwidth. For the transmission mainly lower frequency bands are used which are more narrowband than classical radar frequencies. To compensate this resolution problem the combination of a pseudo-noise coded pulse compression system with superresolution time of arrival estimation is proposed. Coded pulsecompression allows secure and fast distance measurement in multi-user scenarios which can easily be adapted for data transmission purposes (Morhart and Biebl, 2009). Due to the lack of available signal bandwidth the measurement accuracy degrades especially in multipath scenarios. Superresolution time of arrival algorithms can improve this behaviour by estimating the channel impulse response out of a band-limited channel view. For the given test system the implementation of a MUSIC algorithm permitted a two times better distance resolution as the standard pulse compression.

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29

Kim, Sang-Wook, Se-Yun Kim, and Sangwook Nam. "Estimation of the penetration angle of a man-made tunnel using time of arrival measured by short-pulse cross-borehole radar." GEOPHYSICS 75, no. 3 (May 2010): J11—J18. http://dx.doi.org/10.1190/1.3374356.

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The relatively fast propagation of electromagnetic signals through empty man-made tunnels has played a key role in detecting deep underground tunnels using a short-pulse cross-borehole radar system. Our cross-borehole radar system measured the pulse signatures of an obliquely penetrating tunnel using eight different borehole pairs at a test site in Korea. Compared to the arrival times of the first peaks, the arrival times of the first received signals at an appropriate amplitude level provided an increasingly clear indication of the empty tunnel as its penetration angle became more oblique. A quadratic relationship between the arrival time of the first received signal and the oblique angle of the empty tunnel was obtained in pure granite.

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30

Mikola, P. V., Z. M. Kenzhegulova, and R. S. Surovtsev. "Analysis of the pulse signal propagation in a turn of a meander line of two segments based on lattice diagrams." Journal of Physics: Conference Series 2291, no. 1 (July 1, 2022): 012030. http://dx.doi.org/10.1088/1742-6596/2291/1/012030.

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Abstract The analysis of the propagation of a pulse signal in a turn of a meander line of two segments is carried out. For this purpose, the plotting of lattice diagrams for the even and odd modes is carried out, as well as their subsequent comparison with the time responses to the pulse excitation in each node of the line. A complete coincidence of the amplitudes and arrival times of pulses obtained by different methods was obtained.

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31

Molyneux, Joseph B., and Douglas R. Schmitt. "First‐break timing: Arrival onset times by direct correlation." GEOPHYSICS 64, no. 5 (September 1999): 1492–501. http://dx.doi.org/10.1190/1.1444653.

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In attenuating media, pulse characteristics evolve with propagation distance and saturation or pressure‐dependent changes in rock properties. This nonstationarity of the waveform complicates determination of meaningful traveltimes. As a result, depending on the time‐picking criteria used, substantially different values of interval velocity can be obtained. This problem is particularly severe in high‐frequency laboratory time‐of‐flight measurements on porous rock. A potentially less ambiguous measure of wave speed is the signal velocity that is calculated using the pulse onset time. Here, a semiautomated method is developed to determine this onset time in high‐fidelity, pressure‐dependent core measurements. The greatest value of Pearson’s correlation coefficient between segments of observed waveforms near the pulse onset and at an appropriate reference serves as the time determination criterion. Tests of the method on artificial data suggest the signal velocity may be determined to better than 0.3% for −60 dB noise or 1.2% for −37 dB noise. A real data set is tested, comprised of a series of ultrasonic (1 MHz) velocity measurements in microcracked rock to confining pressures of 300 MPa (∼45,000 psi). At the lowest confining pressure, where attenuation is greatest, signal onset and more conventionally derived traveltimes differ by more than 4%. This large discrepancy illustrates that care should be exercised when determining velocity in such attenuating materials. Conversely, the consistency of waveform attributes, such as the difference between the onset time and the first peak time or the apparent quality factor, is useful when estimating intrinsic material velocities in low‐porosity, microcracked carbonate and metamorphic rocks at high confining pressures.

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32

Zhao, Xiu Ying, Hong Yu Wang, Cheng Zhi Yang, and Hong Chao Wu. "A New PRI Transform for the Deinterleaving of Radar Pulses." Applied Mechanics and Materials 109 (October 2011): 528–31. http://dx.doi.org/10.4028/www.scientific.net/amm.109.528.

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This paper presents a new algorithm for the deinterleaving of radar signals, using the direction of arrival (DOA), carrier frequency (RF), and time of arrival (TOA). The algorithm is mainly applied to pulse repetition interval (PRI) signals. This algorithm consists of two steps: In the first step, a PRI transformation is used to the received pulses after pre-deinterleaved of frequency and DOA. In this step, radar signals having the same frequency and DOA are identified as the same class. In the second step, the number of existing emitters and their PRIs is determined by using TOA information. The algorithm for deinterleaving uses the information obtained from the previous analysis to reduce the PRI errors. The simulation results show that the algorithm is successful in high pulse density environments and for the complex signal types.

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33

Ernst, Hannes, Matthieu Scherpf, Hagen Malberg, and Martin Schmidt. "Pulse Arrival Time - A Sensitive Vital Parameter for the Detection of Mental Stress." Current Directions in Biomedical Engineering 7, no. 2 (October 1, 2021): 419–22. http://dx.doi.org/10.1515/cdbme-2021-2106.

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Abstract Mental stress triggers positive inotropic and chronotropic effects as well as peripheral vasoconstriction. This alters the pulse arrival time (PAT), the duration between electrical excitation of the ventricles and arrival of the pulse wave in the periphery. We conducted a study to examine PAT during five rest blocks and under mental stress utilizing the Mannheim Multicomponent Stress Test. Electrocardiograms as well as finger and earlobe photoplethysmograms were recorded. PAT was calculated for over 135,000 heartbeats from 42 healthy volunteers as the time duration between the R peak in the electrocardiogram and the following pulse onset in the respective photoplethysmogram. To identify the effect of mental stress, block-wise PAT means were statistically analyzed with repeated measures ANOVA. The analyses showed significant differences between the block means for both PAT measures (p < 0.001). Post-hoc tests revealed significantly reduced PAT during the stress block compared to all rest blocks for both PAT measures (p < 0.001). We found no significant differences between the rest blocks. Our results support that PAT is a sensitive vital parameter for the detection of mental stress in healthy volunteers. This holds true for both measurement positions, the finger and the earlobe.

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34

Bai, Hua Wei, Yu Wen Wang, and Yu Jiang. "The Improvement of Passive Location Algorithm Based on Time Sequence Estimation." Advanced Materials Research 950 (June 2014): 196–200. http://dx.doi.org/10.4028/www.scientific.net/amr.950.196.

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The multi station time difference sequence of arrival method is a kind of passive location method for pulse radiation source. It takes the advantage of mass time difference information obtained in a very short time to locate the radiation source. This paper models the time difference sequence of arrival process and estimates the time difference according to the characteristic of the time difference sequence. The simulation results show that, the localization after time sequence estimation algorithm can achieve higher positioning accuracy.

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35

Kim, Jung Soo, Ko Keun Kim, Hyun Jae Baek, and Kwang Suk Park. "Effect of confounding factors on blood pressure estimation using pulse arrival time." Physiological Measurement 29, no. 5 (May 1, 2008): 615–24. http://dx.doi.org/10.1088/0967-3334/29/5/007.

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36

Sumino, Yoichi, and Robert C. Waag. "Measurements of ultrasonic pulse arrival time differences produced by abdominal wall specimens." Journal of the Acoustical Society of America 90, no. 6 (December 1991): 2924–30. http://dx.doi.org/10.1121/1.401766.

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37

Eickholt, C., T. Drexel, J. Muehlsteff, A. Ritz, M. Siekiera, K. Kirmanoglou, D. I. Shin, T. Rassaf, M. Kelm, and C. Meyer. "Neurally mediated syncope prediction based on heart rate and pulse arrival time." European Heart Journal 34, suppl 1 (August 2, 2013): 796. http://dx.doi.org/10.1093/eurheartj/eht308.796.

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38

Zhang, Rongrong, and Xiaodai Dong. "A New Time of Arrival Estimation Method Using UWB Dual Pulse Signals." IEEE Transactions on Wireless Communications 7, no. 6 (June 2008): 2057–62. http://dx.doi.org/10.1109/twc.2008.070112.

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39

Sumino, Yoichi, and Robert C. Waag. "Measurements of ultrasonic pulse arrival time differences produced by abdominal wall specimens." Journal of the Acoustical Society of America 88, S1 (November 1990): S166—S167. http://dx.doi.org/10.1121/1.2028731.

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40

Augusteijn, Thomas. "Spin Period Variations of the White Dwarf in FO Aqr/H2215-086." International Astronomical Union Colloquium 122 (1990): 50–52. http://dx.doi.org/10.1017/s0252921100068317.

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AbstractAn investigation of the rotation period variation of the white dwarf in FO Aqr/H2215-086 is presented. A cubic ephemeris is derived for the arrival times of maxima of the pulse light curve which is associated with the white dwarf rotation. Potential problems, resulting from variations of the pulse arrival time as function of orbital phase, and from the change with wavelength of the pulse light curve shape, are investigated. A possible explanation is given for the second effect, being caused by a variable contribution of a modulation at the beat period (of the pulse and orbital periods) as a function of orbital phase.

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41

Yuan, Shuo, and Zhang-Meng Liu. "Temporal Feature Learning and Pulse Prediction for Radars with Variable Parameters." Remote Sensing 14, no. 21 (October 29, 2022): 5439. http://dx.doi.org/10.3390/rs14215439.

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Many modern radars use variable pulse repetition intervals (PRI) to improve anti-reconnaissance and anti-jamming performance. Their PRI features are probably software-defined, but the PRI values at different time instants are variable. Previous statistical pattern analyzing methods are unable to extract such undetermined PRI values and features, which greatly increases the difficulty of Electronic Support Measures (ESM) against such radars. In this communication, we first establish a model to describe the temporal patterns of software-defined radar pulse trains, then introduce the recurrent neural network (RNN) to mine high-order relationships between successive pulses, and finally exploit the temporal features to predict the time of arrival of upcoming pulses. In the simulation part, we compare different time series prediction models to verify the RNN’s adaptability for pulse sequences of variable parameter radars. Moreover, behaviors of different RNN units in this task are compared, and the results show that the proposed method can learn complex PRI features in pulse trains even in the presence of significant data noises and agile PRIs.

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42

Esmaili, Amirhossein, Mohammad Kachuee, and Mahdi Shabany. "Nonlinear Cuffless Blood Pressure Estimation of Healthy Subjects Using Pulse Transit Time and Arrival Time." IEEE Transactions on Instrumentation and Measurement 66, no. 12 (December 2017): 3299–308. http://dx.doi.org/10.1109/tim.2017.2745081.

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43

Liu, Yan, and Fucheng Guo. "Performance Analysis of TDOA and FDOA Estimation for Pulse Signals." International Journal of Antennas and Propagation 2022 (March 16, 2022): 1–12. http://dx.doi.org/10.1155/2022/7672417.

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Time difference of arrival (TDOA) and frequency difference of arrival (FDOA) are effective measurements for localizing emitters’ radiating pulse signals, such as radar. Temporal sparsity of pulse signals makes their TDOA and FDOA estimation precisions much different from that of continuous communication and acoustic signals. The way how the precisions are affected by various parameters, e.g., temporal duration of signals, may also deviate significantly in scenarios of pulse signals from that of continuous ones. In this paper, theoretical analyses are carried out to reveal the Cramer–Rao lower bounds (CRLBs) of TDOA and FDOA estimation precisions of pulse signals and also to obtain insights on how the CRLBs are affected by various parameters, including pulse number, signal-to-noise ratio (SNR), pulse width, and pulse repetition interval (PRI). Simulation results verify the correctness of the derived CRLBs and their variations with different parameters.

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44

Yoshida, Kazuki, and Kazuya Murao. "Load Position Estimation Method for Wearable Devices Based on Difference in Pulse Wave Arrival Time." Sensors 22, no. 3 (January 31, 2022): 1090. http://dx.doi.org/10.3390/s22031090.

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With the increasing use of wearable devices equipped with various sensors, information on human activities, biometrics, and surrounding environments can be obtained via sensor data at any time and place. When such devices are attached to arbitrary body parts and multiple devices are used to capture body-wide movements, it is important to estimate where the devices are attached. In this study, we propose a method that estimates the load positions of wearable devices without requiring the user to perform specific actions. The proposed method estimates the time difference between a heartbeat obtained by an ECG sensor and a pulse wave obtained by a pulse sensor, and it classifies the pulse sensor position from the estimated time difference. Data were collected at 12 body parts from four male subjects and one female subject, and the proposed method was evaluated in both user-dependent and user-independent environments. The average F-value was 1.0 when the number of target body parts was from two to five.

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45

Heijhoff, K., K. Akiba, R. Ballabriga, M. van Beuzekom, M. Campbell, A. P. Colijn, M. Fransen, R. Geertsema, V. Gromov, and X. Llopart Cudie. "Timing performance of the Timepix4 front-end." Journal of Instrumentation 17, no. 07 (July 1, 2022): P07006. http://dx.doi.org/10.1088/1748-0221/17/07/p07006.

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Abstract A characterisation of the Timepix4 pixel front-end with a strong focus on timing performance is presented. Externally generated test pulses were used to probe the per-pixel time-to-digital converter (TDC) and measure the time-bin sizes by precisely controlling the test-pulse arrival time in steps of 10 ps. The results indicate that the TDC can achieve a time resolution of 60 ps, provided that a calibration is performed to compensate for frequency variation in the voltage controlled oscillators of the pixel TDCs. The internal clock distribution system of Timepix4 was used to control the arrival time of internally generated analog test pulses in steps of about 20 ps. The analog test pulse mechanism injects a controlled amount of charge directly into the analog front-end (AFE) of the pixel, and was used to measure the time resolution as a function of signal charge, independently of the TDC. It was shown that for the default configuration, the AFE time resolution in the hole-collecting mode is limited to 105 ps. However, this can be improved up to about 60 ps by increasing the preamplifier bias-current at the cost of increased power dissipation. For the electron-collecting mode, an AFE time resolution of 47 ps was measured for a bare Timepix4 device at a signal charge of 21 ke. It was observed that additional input capacitance from a bonded sensor reduces this figure to 62 ps.

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46

Leonard, M., A. Metcalfe, M. Lambert, and G. Kuczera. "Implementing a space-time rainfall model for the Sydney region." Water Science and Technology 55, no. 4 (February 1, 2007): 39–47. http://dx.doi.org/10.2166/wst.2007.093.

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This paper investigates a Spatial Neyman–Scott Rectangular Pulse (SNSRP) model, which is one of only a few models capable of continuous simulation of rainfall in both space and time. The SNSRP is a spatial extension of the Neyman–Scott Rectangular Pulse model at a single point. The model is highly idealized having six parameters: storm arrival, cell arrival, cell radius, cell lifetime and two cell intensity parameters. A spatial interpolation of the scale parameter is used so that the model can be simulated continuously in space, rather than as a multi-site model. The parameters are calibrated using least-squares fits to statistical moments based on data aggregated to hourly and daily totals. The SNSRP model is calibrated to a very large network of 85 gauges over metropolitan Sydney and shows a good agreement to calibrated statistics. A simulation of 50 replicates over the region compares favourably to several observed temporal statistics, with an example given for one site. A qualitative discussion of the simulated spatial images demonstrates the underlying structure of non-advecting cylindrical cells.

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47

Edsall, Connor W., Laura Huynh, Timothy L. Hall, and Eli Vlaisavljevich. "Bubble-cloud characteristics and ablation efficiency in dual-frequency intrinsic threshold histotripsy." Journal of the Acoustical Society of America 152, no. 4 (October 2022): A249. http://dx.doi.org/10.1121/10.0016169.

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Intrinsic threshold histotripsy has been shown to nucleate bubble clouds and generate ablation closely matching the dimensions of the focal region above the intrinsic threshold (∼25–28MPa) with the ablation efficiency dependent upon the size and density of bubbles within the cloud. This work investigates the effects of dual-frequency histotripsy pulsing on bubble-cloud characteristics and ablation efficiency. Histotripsy was applied to agarose tissue phantoms (1%) using a dual-frequency 500kHz–3MHz array transducer with equal pressure delivered by each frequency. The arrival time of the 3 MHz pulse was varied relative to the 500 kHz pulse, and high-speed imaging was used to characterize the bubble-cloud dimensions, bubble density, and individual bubble size. Ablation was determined using red blood cell phantoms. Results indicated that dual-frequency pulsing generated bubble clouds with intermediate cloud size, bubble size, and bubble density compared to single-frequency (500 kHz and 3 MHz) pulsing, with these characteristics further modulated by the respective pulse arrival times. Additionally, dual-frequency pulsing increased ablation efficiency compared to previously published single frequencies (500 kHz and 3 MHz) with the most efficient ablation observed for cases where the 3 MHz pulse arrived at the leading edge of the 500 kHz pulse. Overall, this investigation demonstrates possible benefits of dual-frequency histotripsy pulsing, warranting further investigation.

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48

Song, Chiwon, Young Jin Kim, Chang Beck Cho, Won Jong Chin, and Kwang-Yeun Park. "Estimation on Embedment Length of Anchor Bolt inside Concrete Using Equation for Arrival Time and Shortest Time Path of Ultrasonic Pulse." Applied Sciences 10, no. 24 (December 10, 2020): 8848. http://dx.doi.org/10.3390/app10248848.

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The bearings or the seismic isolation bearings that play a critical role in bridge structures are fixed to the substructure by anchor bolts. However, the embedment depth of the constructed anchor bolts does often not reach the designed one and may lead to safety issues. The present study proposes an ultrasonic non-destructive testing (NDT) method to verify the embedment depth of the anchor bolts installed on bridges in-service. The P-wave of 50–100 kHz that is usually used in the NDT of concrete was transmitted from the head of the anchor bolt and its arrival time on the concrete cover was measured. The shortest arrival time of the ultrasonic pulse and the corresponding path were then analyzed to formulate their relationship and obtain the distance traveled by the ultrasonic pulse along the anchor by inverse analysis using the equation error estimation. The instability occurring in the inverse analysis is settled by regularization. Finally, the embedment depth of the anchor bolt can be estimated by the analysis of the graph plotting the position of the ultrasonic transmitter and the distance traveled by the pulse along the anchor. The proposed method is validated numerically and experimentally. The method is expected to contribute to the NDT of civil structures by making it possible to estimate the embedment depth of anchor bolts by the means of ultrasonic transducers using P-waves of 50–100 kHz.

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49

YAO, Zhen, Hong MA, Cheng-Guo LIANG, and Li CHENG. "Pulse Arrival Time Estimation Based on Multi-Level Crossing Timing and Receiver Training." IEICE Transactions on Communications E97.B, no. 9 (2014): 1984–89. http://dx.doi.org/10.1587/transcom.e97.b.1984.

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50

Hedge, Eric T., Robert Amelard, and Richard L. Hughson. "Evaluation of Pulse Arrival Time Model to Estimate Systolic Blood Pressure during Exercise." FASEB Journal 34, S1 (April 2020): 1. http://dx.doi.org/10.1096/fasebj.2020.34.s1.05902.

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