Relevant bibliographies by topics / Phase spectrogram

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Phase spectrogram'

Author: Grafiati
Published: 4 June 2021
Last updated: 10 February 2022

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Journal articles on the topic "Phase spectrogram"

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Léonard, François. "Phase spectrogram and frequency spectrogram as new diagnostic tools." Mechanical Systems and Signal Processing 21, no. 1 (January 2007): 125–37. http://dx.doi.org/10.1016/j.ymssp.2005.08.011.

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Yatabe, Kohei, Yoshiki Masuyama, Tsubasa Kusano, and Yasuhiro Oikawa. "Representation of complex spectrogram via phase conversion." Acoustical Science and Technology 40, no. 3 (May 1, 2019): 170–77. http://dx.doi.org/10.1250/ast.40.170.

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Yang, Yuan, Jian Gang Bi, Hong Jie Wang, and Nan Meng. "Study of the Ultrasonic Characteristics of Typical Partial Discharge on GIS." Advanced Materials Research 753-755 (August 2013): 2200–2207. http://dx.doi.org/10.4028/www.scientific.net/amr.753-755.2200.

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This Paper studied the typical PD in GIS by ultrasonic method. A GIS PD simulating and testing system is established, including a PD simulating system, an ultrasonic detecting system and a conventional pulse current method measurement system. The thesis focuses on four typical kinds of PD signals in GIS, including metal particles, bad contacts on high and grounding potential conductor, the protrusion on the high potential conductor. The statistics characteristics are obtained which include N-Φ spectrogram (relationship between discharge frequency and discharge phase Spectrogram) and Umax-Φ spectrogram (relationship between discharge amplitude and discharge phase Spectrogram). Experimental results show that low-frequency ultrasonic sensors can detect this four PD signals， signal spectra analysis shows that ultrasonic signals of different statistical model are with different characteristics. The results provide test data for the pattern recognition of Partial Discharge in GIS.
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Rajshekhar, G., Sai Siva Gorthi, and Pramod Rastogi. "Estimation of the phase derivative using an adaptive window spectrogram." Journal of the Optical Society of America A 27, no. 1 (December 9, 2009): 69. http://dx.doi.org/10.1364/josaa.27.000069.

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Keang-Po Ho, Hsi-Cheng Wang, Hau-Kai Chen, and Cheng-Chen Wu. "Electric field characterization for phase-Modulated signals using measured spectrogram." IEEE Photonics Technology Letters 17, no. 10 (October 2005): 2143–45. http://dx.doi.org/10.1109/lpt.2005.854420.

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Song, Fuxian, H. Sadi Kuleli, M. Nafi Toksöz, Erkan Ay, and Haijiang Zhang. "An improved method for hydrofracture-induced microseismic event detection and phase picking." GEOPHYSICS 75, no. 6 (November 2010): A47—A52. http://dx.doi.org/10.1190/1.3484716.

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The ability to detect small microearthquakes and identify their P- and S-phase arrivals is a key issue in hydrofracture downhole monitoring because of the low signal-to-noise ratios (S/N). An array-based waveform correlation approach (matched filter) is applied to improve the detectability of small magnitude events with mechanisms and locations similar to a nearby master event. After detecting the weak events, a transformed spectrogram method is used to identify the phase arrivals. The technique has been tested on a downhole monitoring data set of the microseismic events induced by hydraulic fracturing. It is shown that, for this case, one event with a S/N around [Formula: see text], which is barely detectable using an array-stacked short-time average/long-time average (STA/LTA) detector under a reasonable false alarm rate, is readily detected on the array-stacked correlation traces. The transformed spectrogram analysis of the detected events improves P- and S-phase picking.
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Tanimura, Kazunori, Tsuyoshi Konishi, Kazuyoshi Itoh, and Yoshiki Ichioka. "Amplitude and Phase Retrieval of Ultrashort Optical Pulse Using Optical Spectrogram Scope." Optical Review 10, no. 2 (March 2003): 77–81. http://dx.doi.org/10.1007/s10043-003-0077-9.

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Yin, Dacheng, Chong Luo, Zhiwei Xiong, and Wenjun Zeng. "PHASEN: A Phase-and-Harmonics-Aware Speech Enhancement Network." Proceedings of the AAAI Conference on Artificial Intelligence 34, no. 05 (April 3, 2020): 9458–65. http://dx.doi.org/10.1609/aaai.v34i05.6489.

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Time-frequency (T-F) domain masking is a mainstream approach for single-channel speech enhancement. Recently, focuses have been put to phase prediction in addition to amplitude prediction. In this paper, we propose a phase-and-harmonics-aware deep neural network (DNN), named PHASEN, for this task. Unlike previous methods which directly use a complex ideal ratio mask to supervise the DNN learning, we design a two-stream network, where amplitude stream and phase stream are dedicated to amplitude and phase prediction. We discover that the two streams should communicate with each other, and this is crucial to phase prediction. In addition, we propose frequency transformation blocks to catch long-range correlations along the frequency axis. Visualization shows that the learned transformation matrix implicitly captures the harmonic correlation, which has been proven to be helpful for T-F spectrogram reconstruction. With these two innovations, PHASEN acquires the ability to handle detailed phase patterns and to utilize harmonic patterns, getting 1.76dB SDR improvement on AVSpeech + AudioSet dataset. It also achieves significant gains over Google's network on this dataset. On Voice Bank + DEMAND dataset, PHASEN outperforms previous methods by a large margin on four metrics.
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Grochowalski, Jacek Michał, and Tomasz Chady. "Pulsed Multifrequency Excitation and Spectrogram Eddy Current Testing (PMFES-ECT) for Nondestructive Evaluation of Conducting Materials." Materials 14, no. 18 (September 15, 2021): 5311. http://dx.doi.org/10.3390/ma14185311.

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This paper presents a new method for nondestructive testing—a pulsed multifrequency excitation and spectrogram eddy current testing (PMFES-ECT), which is an extension of the multifrequency excitation and spectrogram eddy current testing. The new method uses excitation in the form of pulses repeated at a specified time, containing several periods of a waveform consisting of the sum of sinusoids with a selected frequency, amplitude and phase. This solution allows the maintenance of the advantages of multifrequency excitation and, at the same time, generates high energy pulses similar to those used in pulse eddy current testing (PECT). The effectiveness of the new method was confirmed by numerical simulations and the measurement of thin Inconel plates, consisting of notches manufactured by the electric-discharge method.
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Zheng, Kai, Wei Ben Yang, Yu Hua Han, and Hong Yi Li. "Preparing γ-Crystalline Controlling Thickness's Zn-Ni Coating and Studying Corrosion Performance." Advanced Materials Research 1053 (October 2014): 337–42. http://dx.doi.org/10.4028/www.scientific.net/amr.1053.337.

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This paper aimed to prepare a kind of γ-phase crystal Zn-Ni coating outside the surface of low carbon steel, to investigate the relationship between coating's thickness and electrochemical parameters and to testify its corrosion performance. The X-ray diffraction (XRD) spectrogram of coating was almost the same as that of standard. The data of scanning electron microscope spectrogram (SEM) showed that coating was made from 16 percents Ni and 84 percents Zn. During the coating developing, the thickness of coating unfolded a regulation that was fast in the beginning of 0.5 hour and slow afterwards. The anti-corrosion performance of the coating was also studied by analyzing electrochemical impedance spectroscopy (EIS) data. The analyzing result indicated that the impedance of γ-shape crystal Zn-Ni coating with was stable.
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Dissertations / Theses on the topic "Phase spectrogram"

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Kubánková, Anna. "Automatická klasifikace digitálních modulací." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-233424.

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This dissertation thesis deals with a new method for digital modulation recognition. The history and present state of the topic is summarized in the introduction. Present methods together with their characteristic properties are described. The recognition by means of artificial neural is presented in more detail. After setting the objective of the dissertation thesis, the digital modulations that were chosen for recognition are described theoretically. The modulations FSK, MSK, BPSK, QPSK, and QAM-16 are concerned. These modulations are mostly used in modern communication systems. The method designed is based on the analysis of module and phase spectrograms of the modulated signals. Their histograms are used for the examination of the spectrogram properties. They provide information on the count of carrier frequencies in the signal, which is used for the FSK and MSK recognition, and on the count of phase states on which the BPSK, QPSK, and QAM-16 are classified. The spectrograms in that the characteristic attributes of the modulations are visible are obtained with the segment length equal to the symbol length. It was found that it is possible to correctly recognize the modulation with the known symbol length at the signal-to-noise ratio at least 0 dB. That is why it is necessary to detect the symbol length prior to the spectrogram calculation. Four methods were designed for this purpose: autocorrelation function, cepstrum analysis, wavelet transform, and LPC coefficients. These methods were algorithmized and analyzed with signals disturbed by the white Gaussian noise, phase noise and with signals passed through a multipass fading channel. The method of detection by means of cepstrum analysis proved the most suitable and reliable. Finally the new method for digital modulation recognition was verified with signals passed through a channel with properties close to the real one.
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Tyas, Luke Martin Graham. "The SALT HRS Spectrograph." Thesis, Durham University, 2012. http://etheses.dur.ac.uk/3492/.

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SALT HRS (Southern African Large Telescope High Resolution Échelle Spectrograph) is a high-resolution, high-efficiency spectrograph for the 11m SALT telescope in Sutherland, South Africa. The initial optical design work was performed at the University of Canterbury, New Zealand. Revisions to the concept, the mechanical design, manufacture, assembly and testing have been handled by the Centre for Advanced Instrumentation, at Durham University in the United Kingdom. SALT HRS is a fibre-fed echelle grating spectrograph with four operational modes: low-, medium- and high-resolution and high-stability modes, having spectral resolutions of R ≈16000, 37000, 67000 and 67000 respectively over a wavelength range of 370-890nm. The instrument is of a dual channel, ‘white pupil’ design, in which the primary mirror acts to collimate light onto a single R4 echelle grating, and also to focus dispersed light to an intermediate focus. A dichroic beam-splitter separates the dispersed light into two separate spectral channels. Spherical pupil mirrors transfer the separated beams via a fold mirror to two wavelength-specific volume-phase holographic gratings (VPHGs) used as cross-dispersers. Cross-dispersed spectra are then imaged by two fully dioptric camera systems onto optimized CCD detectors. This thesis presents the results of the laboratory testing and specification of several critical sub-systems of SALT HRS, as well as the development of key software tools for the design verification and operation at the telescope. In Chapter 1 we first review the technical development of high-resolution spectroscopy and its specific implementation in SALT HRS. In Chapter 2 we develop a comprehensive throughput model of the entire system based on a combination of as-built performance and specific throughput measurements in the laboratory. This is used to make some specific predictions for the on-sky performance of SALT HRS and the magnitude limits for science targets. We also present a graphical exposure time calculator based on these measurements which can be used by an astronomer to plan their observations with SALT HRS. Chapter 3 contains a detailed treatise on the optical fibre system of SALT HRS. Considerations for the use of optical fibres in astronomy are provided, as are details of an optional double scrambler, and the various instrument fibre modes. Extensive measurements of focal ratio degradation (FRD) are also presented, with testing of input beam speed; wavelength; fibre bending; variable pupil mirror illumination; and vacuum tank pressure dependency. The systems for fibre management are reviewed, as is the fibre bundle assembly process. Testing of two further sub-systems is described in Chapter 4. Firstly the long-term stability of the mirror mounting mechanisms is determined. The advantages of cross-dispersion of echelle spectra using volume-phase holographic gratings are then discussed, and the results of diffraction efficiency measurements are given for both red and blue channel gratings. Modern CCD technologies are examined in Chapter 5, and the blue detector is experimentally characterized using photon transfer and quantum efficiency curves. It is also used for an investigation into cosmic ray events in CCDs. Results from shielding the detector using lead are described, as is an attempt to distinguish the source of the events based on their morphology. Finally, Chapter 6 deals with the handling of data produced by SALT HRS. Methods of wavelength calibration of the spectra are discussed, including the use of Thorium-Argon lamps and an iodine absorption cell. The implementation of a Python based quick-look data reduction pipeline is reviewed, with a description of the processes performed. A summary of the thesis is given in Chapter 7.
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Navarro, Laurent. "Représentation tridimensionnelle de la phase d'un signal dans un plan temps-fréquence. Contribution à l'analyse des signaux quasi-stationnaires." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2007. http://tel.archives-ouvertes.fr/tel-00294663.

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Cette thèse de doctorat porte sur la représentation tridimensionnelle de la phase dans un plan temps-fréquence. L'application aux signaux quasi-stationnaires est effectuée dans ce manuscrit.
La transformée de Fourier à court terme d'un signal est réalisée par convolution de ce dernier avec une fenêtre glissante par rapport au temps. Il en résulte une distribution complexe dans un plan temps-fréquence, où un module et une phase peuvent être calculés.
Le module de la transformée de Fourier à court terme d'un signal contient des informations fréquentielles, dont la précision est limitée par le principe d'inégalité temps-fréquence d'Heisenberg-Gabor. La phase quant à elle contient des informations de localisation temporelle des fréquences beaucoup plus précises que le module, cependant ces informations sont très difficiles à interpréter de manière directe. Les spectrogrammes de fréquence et de phase constituent une solution intéressante pour pallier cette difficulté mais des limitations existent, notamment en ce qui concerne le choix d'un seuil énergétique d'observation.
La formulation continue des spectrogrammes de fréquence et de phase est introduite et étudiée dans ce manuscrit. Celle-ci permet un développement mathématique, pour des signaux dont l'expression analytique est connue, de la phase instantanée. L'analyse de processus quasi stationnaires permet une interprétation du comportement de ces nouvelles représentations et permet ainsi de mettre en évidence certaines de leurs propriétés.
En conséquence, un nouveau concept de représentations tridimensionnelles temps-fréquence-phase et temps-fréquence-faibles variations de fréquence est créé. Ces représentations tridimensionnelles sont réalisées par une opération de "mapping" des spectrogrammes de fréquence et de phase sur le module carré de la transformée de Fourier à court terme.
Les spectrogrammes de fréquence et de phase tridimensionnels ainsi créés permettent l'observation directe des variations de phase et des faibles variations de fréquence en tenant compte des amplitudes (énergie répartie dans le plan temps-fréquence). L'opération de seuillage n'est donc plus nécessaire ou devient seulement une aide à l'interprétation et non pas une limitation de la représentation.
Ces nouvelles représentations se révèlent être des outils performants dans le cadre de l'étude de signaux quasi-stationnaires, comme les signaux musicaux ou les signaux biomédicaux. Elles ouvrent de nouvelles perspectives car elles présentent de manière simple des informations qui nécessitaient auparavant de nombreuses manipulations pour être accessibles.
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Braun, Stefan K. "Aspekte des „Samplings“." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-147027.

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Mash-Ups (auch Bootlegging, Bastard Pop oder Collage genannt) erfreuen sich seit Jahren steigender Beliebtheit. Waren es zu Beginn der 1990er Jahre meist nur 2 unterschiedliche Popsongs, deren Gesangs- und Instrumentenspuren in Remixform ineinander gemischt wurden, existieren heute Multi-Mash-Ups mit mehreren Dutzend gemixten und gesampelten Songs, Interpreten, Videosequenzen und Effekten. Eine Herausforderung stellt die Kombination unterschiedlichster Stile dar, diese zu neuen tanzbaren Titeln aus den Charts zu mischen. Das Mash-Up Projekt Pop Danthology z.B. enthält in einem knapp 6 minütigen aktuellen Musikclip 68 verschiedene Interpreten, u. a. Bruno Mars, Britney Spears, Rhianna und Lady Gaga. Die Verwendung und das Sampeln fremder Musik- und Videotitel kann eine Urheberrechtsverletzung darstellen. Die Komponisten des Titels „Nur mir“ mit Sängerin Sabrina Setlur unterlagen in einem Rechtsstreit, der bis zum BGH führte. Sie haben im Zuge eines Tonträger-Samplings, so der BGH , in das Tonträgerherstellerrecht der Kläger (Musikgruppe Kraftwerk) eingegriffen, in dem sie im Wege des „Sampling“ zwei Takte einer Rhythmussequenz des Titels „Metall auf Metall“ entnommen und diese im eigenen Stück unterlegt haben. Der rasante technische Fortschritt macht es mittlerweile möglich, immer einfacher, schneller und besser Musik-, Film- und Bildaufnahmen zu bearbeiten und zu verändern. Computer mit Bearbeitungssoftware haben Keyboards, Synthesizer und analoge Mehrspurtechnik abgelöst. Die Methoden des Samplings unterscheiden sich von der klassischen Raubkopie dahingehend, dass mit der Sampleübernahme eine weitreichende Umgestaltung und Bearbeitung erfolgt. Die Raubkopie zeichnet sich durch eine unveränderte Übernahme des Originals aus. Betroffen von den Auswirkungen eines nicht rechtmäßig durchgeführten Sampling sind Urheber- und Leistungsschutzrechte ausübender Künstler sowie Leistungsschutzrechte von Tonträgerherstellern. U. U. sind auch Verstöße gegen das allgemeine Persönlichkeits- und Wettbewerbsrecht Gegenstand von streitigen Auseinandersetzungen.
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Books on the topic "Phase spectrogram"

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The infrared spectrograph during the SIRTF pre-definition phase: Final grant report for NASA-Ames grant NAG2-317. [Moffett Field, Calif: National Aeronautics and Space Administration, Ames Research Center, 1988.

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Book chapters on the topic "Phase spectrogram"

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Justin, Judith, and Vanithamani R. "Speech Enhancement Using Neuro-Fuzzy Classifier." In Advances in Data Mining and Database Management, 164–81. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-6659-6.ch009.

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In this chapter, a speech enhancement technique is implemented using a neuro-fuzzy classifier. Noisy speech sentences from NOIZEUS and AURORA databases are taken for the study. Feature extraction is implemented through modifications in amplitude magnitude spectrograms. A four class neuro-fuzzy classifier splits the noisy speech samples into noise-only part, signal only part, more noise-less signal part, and more signal-less noise part of the time-frequency units. Appropriate weights are applied in the enhancement phase. The enhanced speech sentence is evaluated using objective measures. An analysis of the performance of the Neuro-Fuzzy 4 (NF 4) classifier is done. A comparison of the performance of the classifier with other conventional techniques is done for various noises at different noise levels. It is observed that the numerical values of the measures obtained are better when compared to the others. An overall comparison of the performance of the NF 4 classifier is done and it is inferred that NF4 outperforms the other techniques in speech enhancement.
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Conference papers on the topic "Phase spectrogram"

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Sandsten, Maria, Rachele Anderson, Isabella Reinhold, and Johan Brynolfsson. "The Matched Reassigned Cross-Spectrogram for Phase Estimation." In ICASSP 2020 - 2020 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP). IEEE, 2020. http://dx.doi.org/10.1109/icassp40776.2020.9053684.

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Parry, R. Mitchell, and Irfan Essa. "Incorporating Phase Information for Source Separation via Spectrogram Factorization." In 2007 IEEE International Conference on Acoustics, Speech, and Signal Processing. IEEE, 2007. http://dx.doi.org/10.1109/icassp.2007.366322.

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Masuyama, Yoshiki, Kohei Yatabe, and Yasuhiro Oikawa. "Low-rankness of Complex-valued Spectrogram and Its Application to Phase-aware Audio Processing." In ICASSP 2019 - 2019 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP). IEEE, 2019. http://dx.doi.org/10.1109/icassp.2019.8683100.

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Hidaka, Shunsuke, Yogaku Lee, Kohei Wakamiya, Takashi Nakagawa, and Tokihiko Kaburagi. "Automatic Estimation of Pathological Voice Quality Based on Recurrent Neural Network Using Amplitude and Phase Spectrogram." In Interspeech 2020. ISCA: ISCA, 2020. http://dx.doi.org/10.21437/interspeech.2020-3228.

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Nouvel, Bertrand. "A study of a local-features-aware model for the problem of phase reconstruction from the magnitude spectrogram." In 2010 IEEE International Conference on Acoustics, Speech and Signal Processing. IEEE, 2010. http://dx.doi.org/10.1109/icassp.2010.5495756.

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Saito, Akira, Junta Umemoto, Kohei Noguchi, Meng-Hsuan Tien, and Kiran D’Souza. "Experimental Forced Response Analysis of Two-Degree-of-Freedom Piecewise-Linear Systems With a Gap." In ASME 2020 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/detc2020-22289.

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Abstract In this paper, an experimental forced response analysis for a two degree of freedom piecewise-linear oscillator is discussed. First, a mathematical model of the piecewise linear oscillator is presented. Second, the experimental setup developed for the forced response study is presented. The experimental setup is capable of investigating a two degree of freedom piecewise linear oscillator model. The piecewise linearity is achieved by attaching mechanical stops between two masses that move along common shafts. Forced response tests have been conducted, and the results are presented. Discussion of characteristics of the oscillators are provided based on frequency response, spectrogram, time histories, phase portraits, and Poincaré sections. Period doubling bifurcation has been observed when the excitation frequency changes from a frequency with multiple contacts between the masses to a frequency with single contact between the masses occurs.
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Seelamantula, Chandra Sekhar. "Phase-Encoded Speech Spectrograms." In Interspeech 2016. ISCA, 2016. http://dx.doi.org/10.21437/interspeech.2016-1600.

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Vashisht, Rajiv Kumar, and Qingjin Peng. "Dynamic Modelling and Diagnosis of Transverse Crack and Rotor/Stator Rub in a Flexible Rotor System." In ASME 2019 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/detc2019-97047.

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Abstract Due to unbalance present in a rotating machinery, fluctuating stresses are generated leading to the formation of transverse cracks in rotors. The cracks propagate with the passage of time and increase the amplitude of vibration. High vibration amplitudes can give rise to rotor/stator rubs. During the rubbing phase, the crack propagation gets enhanced due to inter-connected nature of these faults. If left unattended, these faults can cause the premature failure of machine components. Hence, there is a need to develop fault detection mechanisms based on the vibration response so that these faults can be diagnosed during initial stages. The effect of gravity and the presence of cracks significantly changes vibration characteristics of the rotor, which is thoroughly investigated in this research for a two-degrees-of-freedom Jeffcott rotor. It has been observed that during rubbing, high harmonics are excited. These harmonics are integer multiple of the rotor spin frequency. Similar type of the response is also observed due to the presence of a transverse rotor crack. It is difficult to distinguish the type of faults based on the steady state dynamic response only. Instead of working only on a steady state vibration response, the transient vibration response during coasting up of the rotor is considered. During coasting up of the rotor, high harmonics are excited for both the crack as well as rotor/stator rubbing. The excitation of higher harmonics starts at much earlier in the spectrogram of the vertical response for the cracked rotor compared to that of rubbing. This fact is used in the development of a fault diagnosis technique based on Short Time Fourier Transform of the vibration response. The proposed technique can efficiently distinguish different types of faults even if multiple faults coexist.
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Bernstein, Gary M., Alex E. Athey, Rebecca Bernstein, Steven M. Gunnels, Douglas O. Richstone, and Stephen A. Shectman. "Volume-phase holographic spectrograph for the Magellan telescopes." In International Symposium on Optical Science and Technology, edited by Allen M. Larar and Martin G. Mlynczak. SPIE, 2002. http://dx.doi.org/10.1117/12.454281.

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Di Marcantonio, Paolo, Isabelle Boisse, Roberto Cirami, Guido Cupani, Igor Di Varano, Holger Drass, Pedro Figueira, et al. "ELT high resolution spectrograph: phase-A software architecture study." In Software and Cyberinfrastructure for Astronomy V, edited by Juan C. Guzman and Jorge Ibsen. SPIE, 2018. http://dx.doi.org/10.1117/12.2311296.

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