scholarly journals Acoustical Respiratory Monitoring in the Time Domain

2019 ◽  
Vol 13 (1) ◽  
pp. 144-151
Author(s):  
D. John Doyle
Keyword(s):  
Time Domain ◽  
Signal Amplification ◽  
Digital Audio ◽  
External Ear ◽  
Proof Of Concept ◽  
Ear Canal ◽  
Technical Details ◽  
Acoustical Monitoring ◽  
The Time Domain ◽  
Breath Sound Analysis

This paper introduces the reader to some of the various methods that are available for the time-domain bio-acoustical monitoring of patient breathing. Technical details concerning microphone selection, calibration and characterization, signal amplification, signal filtering and waveform recording are presented. We also describe proof of concept recordings obtained from the neck, from the external ear canal, from a microphone embedded into an oxygen mask and from a leak-free microphone pneumatically connected to the cuff of a laryngeal mask airway. We recommend Audacity, an open-source digital audio editor and recording package that can be freely downloaded at https://www.audacityteam.org for investigators seeking to conduct research on breath sound analysis.

scholarly journals INFLUENCE FUNCTIONAL FOR DECOHERENCE OF INTERACTING ELECTRONS IN DISORDERED CONDUCTORS

2008 ◽  
Vol 22 (07) ◽  
pp. 727-833 ◽  
Author(s):  
JAN VON DELFT
Keyword(s):  
Time Domain ◽  
Functional Approach ◽  
Main Text ◽  
Decoherence Rate ◽  
Interacting Electrons ◽  
Accurate Treatment ◽  
Technical Details ◽  
Influence Functional ◽  
Disordered Metals ◽  
The Time Domain

In this review, we rederive the controversial influence functional approach of Golubev and Zaikin (GZ) for interacting electrons in disordered metals in a way that allows us to show its equivalence, before disorder averaging, to diagrammatic Keldysh perturbation theory. By representing a certain Pauli factor [Formula: see text] occuring in GZ's effective action in the frequency domain (instead of the time domain, as GZ do), we also achieve a more accurate treatment of recoil effects. With this change, GZ's approach reproduces, in a remarkably simple way, the standard, generally accepted result for the decoherence rate. — The main text and appendices A.1 to A.3 of the present review are comparatively brief, and have been published previously; for convenience, they are included here again (with minor revisions). The bulk of the review is contained in several additional, lengthy appendices containing the relevant technical details.

scholarly journals Uncovering dynamic textual topics that explain crime

2021 ◽  
Vol 8 (12) ◽  
Author(s):  
Seppo Virtanen
Keyword(s):  
Time Domain ◽  
Latent Variables ◽  
Crime Analysis ◽  
Proof Of Concept ◽  
Regression Modelling ◽  
Crime Detection ◽  
Crime Counts ◽  
Mapping Techniques ◽  
The Time Domain ◽  
Spatial Area

Crime analysis/mapping techniques have been developed and applied for crime detection and prevention to predict where and when crime occurs, leveraging historical crime records over a spatial area and covariates for the spatial domain. Some of these techniques may provide insights for understanding crime and disorder, especially, via interpreting the weights for the spatial covariates based on regression modelling. However, to date, the use of temporal covariates for the time domain has not played a significant role in the analysis. In this work, we collect time-stamped crime-related news articles, infer crime topics or themes based on the collection and associate the topics with the historical numeric crime counts. We provide a proof-of-concept study, where instead of adopting spatial covariates, we focus on temporal (or dynamic) covariates and assess their utility. We present a novel joint model tailored for the crime articles and counts such that the temporal covariates (latent variables, more generally) are inferred based on the data sources. We apply the model for violent crime in London.

Apodisation in the time domain

1992 ◽  
Vol 2 (4) ◽  
pp. 615-620
Author(s):  
G. W. Series
Keyword(s):  
Time Domain ◽  
The Time Domain

JOINT INTERPRETATION OF AIRBORNE ELECTROMAGNETIC DATA IN THE TIME DOMAIN AND FREQUENCY DOMAIN

2018 ◽  
Vol 12 (7-8) ◽  
pp. 76-83
Author(s):  
E. V. KARSHAKOV ◽  
J. MOILANEN
Keyword(s):  
Fourier Transform ◽  
Frequency Domain ◽  
Time Domain ◽  
Frequency Interval ◽  
Single Spectrum ◽  
Simultaneous Inversion ◽  
Homogeneous Half Space ◽  
Time Domain Data ◽  
The Time Domain

Тhe advantage of combine processing of frequency domain and time domain data provided by the EQUATOR system is discussed. The heliborne complex has a towed transmitter, and, raised above it on the same cable a towed receiver. The excitation signal contains both pulsed and harmonic components. In fact, there are two independent transmitters operate in the system: one of them is a normal pulsed domain transmitter, with a half-sinusoidal pulse and a small "cut" on the falling edge, and the other one is a classical frequency domain transmitter at several specially selected frequencies. The received signal is first processed to a direct Fourier transform with high Q-factor detection at all significant frequencies. After that, in the spectral region, operations of converting the spectra of two sounding signals to a single spectrum of an ideal transmitter are performed. Than we do an inverse Fourier transform and return to the time domain. The detection of spectral components is done at a frequency band of several Hz, the receiver has the ability to perfectly suppress all sorts of extra-band noise. The detection bandwidth is several dozen times less the frequency interval between the harmonics, it turns out thatto achieve the same measurement quality of ground response without using out-of-band suppression you need several dozen times higher moment of airborne transmitting system. The data obtained from the model of a homogeneous half-space, a two-layered model, and a model of a horizontally layered medium is considered. A time-domain data makes it easier to detect a conductor in a relative insulator at greater depths. The data in the frequency domain gives more detailed information about subsurface. These conclusions are illustrated by the example of processing the survey data of the Republic of Rwanda in 2017. The simultaneous inversion of data in frequency domain and time domain can significantly improve the quality of interpretation.

Rhabdomyosarcoma of the External Ear Canal Treated with Brachytherapy

2016 ◽  
Vol 2016 (1) ◽  
Author(s):  
Mahvish Qureshi MD ◽  
◽  
Sana Farooki MD ◽  
Chibuzo O’Suoji MD ◽  
◽  
...  
Keyword(s):  
External Ear ◽  
Ear Canal ◽  
External Ear Canal

scholarly journals Broadband spectroscopy of astrophysical ice analogues

2019 ◽  
Vol 629 ◽  
pp. A112 ◽  
Author(s):  
B. M. Giuliano ◽  
A. A. Gavdush ◽  
B. Müller ◽  
K. I. Zaytsev ◽  
T. Grassi ◽  
...  
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Time Domain ◽  
Complex Refractive Index ◽  
Far Infrared ◽  
Infrared Region ◽  
Thz Radiation ◽  
The Real ◽  
Thz Range ◽  
The Time Domain

Context. Reliable, directly measured optical properties of astrophysical ice analogues in the infrared and terahertz (THz) range are missing from the literature. These parameters are of great importance to model the dust continuum radiative transfer in dense and cold regions, where thick ice mantles are present, and are necessary for the interpretation of future observations planned in the far-infrared region. Aims. Coherent THz radiation allows for direct measurement of the complex dielectric function (refractive index) of astrophysically relevant ice species in the THz range. Methods. We recorded the time-domain waveforms and the frequency-domain spectra of reference samples of CO ice, deposited at a temperature of 28.5 K and annealed to 33 K at different thicknesses. We developed a new algorithm to reconstruct the real and imaginary parts of the refractive index from the time-domain THz data. Results. The complex refractive index in the wavelength range 1 mm–150 μm (0.3–2.0 THz) was determined for the studied ice samples, and this index was compared with available data found in the literature. Conclusions. The developed algorithm of reconstructing the real and imaginary parts of the refractive index from the time-domain THz data enables us, for the first time, to determine the optical properties of astrophysical ice analogues without using the Kramers–Kronig relations. The obtained data provide a benchmark to interpret the observational data from current ground-based facilities as well as future space telescope missions, and we used these data to estimate the opacities of the dust grains in presence of CO ice mantles.

EPR light beams and non-Gaussian quantum distributions in the time domain

2009 ◽  
Vol 6 (7) ◽  
pp. 577-580
Author(s):  
N. H. Adamyan ◽  
H. H. Adamyan ◽  
G. Yu. Kryuchkyan
Keyword(s):  
Time Domain ◽  
Non Gaussian ◽  
The Time Domain ◽  
Light Beams ◽  
Quantum Distributions

Separating Multiple Moving Sources by Microphone Array Signals for Wayside Acoustic Fault Diagnosis

2019 ◽  
Vol 141 (5) ◽  
Author(s):  
Wei Xiong ◽  
Qingbo He ◽  
Zhike Peng
Keyword(s):  
Fault Diagnosis ◽  
Time Domain ◽  
Feature Matching ◽  
Matching Pursuit ◽  
Microphone Array ◽  
Time Frequency ◽  
Moving Sources ◽  
The Time Domain ◽  
Envelope Spectrum ◽  
Threshold Setting

Wayside acoustic defective bearing detector (ADBD) system is a potential technique in ensuring the safety of traveling vehicles. However, Doppler distortion and multiple moving sources aliasing in the acquired acoustic signals decrease the accuracy of defective bearing fault diagnosis. Currently, the method of constructing time-frequency (TF) masks for source separation was limited by an empirical threshold setting. To overcome this limitation, this study proposed a dynamic Doppler multisource separation model and constructed a time domain-separating matrix (TDSM) to realize multiple moving sources separation in the time domain. The TDSM was designed with two steps of (1) constructing separating curves and time domain remapping matrix (TDRM) and (2) remapping each element of separating curves to its corresponding time according to the TDRM. Both TDSM and TDRM were driven by geometrical and motion parameters, which would be estimated by Doppler feature matching pursuit (DFMP) algorithm. After gaining the source components from the observed signals, correlation operation was carried out to estimate source signals. Moreover, fault diagnosis could be carried out by envelope spectrum analysis. Compared with the method of constructing TF masks, the proposed strategy could avoid setting thresholds empirically. Finally, the effectiveness of the proposed technique was validated by simulation and experimental cases. Results indicated the potential of this method for improving the performance of the ADBD system.

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