Dissertations / Theses on the topic 'Spectrogram analysis'
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Bleakley, Steven Shea, and steven bleakley@qr com au. "Time Frequency Analysis of Railway Wagon Body Accelerations for a Low-Power Autonomous Device." Central Queensland University, 2006. http://library-resources.cqu.edu.au./thesis/adt-QCQU/public/adt-QCQU20070622.121515.
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This thesis examines the application of the techniques of Fourier spectrogram and wavelet analysis to a low power embedded microprocessor application in a novel railway and rollingstock monitoring system.
The safe and cost effective operation of freight railways is limited by the dynamic performance of wagons running on track. A monitoring system has been proposed comprising of low cost wireless sensing devices, dubbed Health Cards, to be installed on every wagon in the fleet. When marshalled into a train, the devices would sense accelerations and communicate via radio network to a master system in the locomotive. The integrated system would provide online information for decision support systems.
Data throughput was heavily restricted by the network architecture, so significant signal analysis was required at the device level. An electronics engineering team at Central Queensland University developed a prototype Health Card, incorporating a 27MHz microcontroller and four dual axis accelerometers. A sensing arrangement and online analysis algorithms were required to detect and categorise dynamic events while operating within the constraints of the system.
Time-frequency analysis reveals the time varying frequency content of signals, making it suitable to detect and characterise transient events. With efficient algorithms such as the Fast Fourier Transform, and Fast Wavelet Transform, time-frequency analysis methods can be implemented on a low power, embedded microcontroller.
This thesis examines the application of time-frequency analysis techniques to wagon body acceleration signals, for the purpose of detecting poor dynamic performance of the wagon-track system. The Fourier spectrogram is implemented on the Health Card prototype and demonstrated in the laboratory. The research and algorithms provide a foundation for ongoing development as resources become available for system testing and validation.
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Kalm, Helen. "Acoustic Soil-Rock Probing : A Case Study in Gubbängen." Thesis, KTH, Jord- och bergmekanik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-256081.
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Soil-rock probing (Jb-probing) is the most common probing method in Sweden. Due to the penetration capacity of the Jb-probing it can be performed in both soil and rock. However, the capacity also results in inherent limitations and uncertainties, such as the difficulty identifying the soil layer sequences of soft soils. In order to attain a more detailed soil layer sequence it is necessary to perform complementary probing and sampling methods, an inefficient and consequently costly procedure. By instead implementing non-interfering complementary methods performed simultaneously as the Jb-probing the method may be rationalized. The so-called acoustic Jb-probing method may be a potential complement to the Jb-probing. In this thesis a continued study of the acoustic Jb-probing method is performed by means of a case study in Gubbängen with the focus on the potential additional information that the spectrogram (a visual representation of the frequency spectra) may contain compared to the Jb-parameters alone. This was done by obtaining vibration signals during Jb-probing using a triaxle geophone installed four meters from the boreholes. Vibration signals were collected from 13 boreholes. The vibration signals were then analyzed in time- and frequency domain which were compared to corresponding Jb-parameters and classified soil types. The results showed that the clay layers held the most promise for discovering additional information in the spectrogram, however this does not exclude potential in other soil types. Additionally, it was shown that the geophone ought to be fastened in the ground in order to attain satisfactory data. Overall, the acoustic Jb-probing method is a favorable way of collecting and analyzing data, which with continued development of the operational and computational process may be an economical alternative to the conventional method.
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Yao, Bing. "ANALYSIS OF ELECTRICAL AND MAGNETIC BIO-SIGNALS ASSOCIATED WITH MOTOR PERFORMANCE AND FATIGUE." Case Western Reserve University School of Graduate Studies / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=case1140813534.
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Krejčí, Michal. "Fourierova transformace a spektrogramy v analýze DNA sekvencí." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219249.
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Various methods of DNA sequences modifications for frequency analysis and basic characteristics of DNA are described in the theoretical part of this thesis. Tricolor spectrograms, created by short time Fourier transform help us to recognize some characteristic patterns in DNA sequences. Practical part of this work deals with developed programme which generates spectrograms and analyse them. Last part deals with the analysis of selected sequences of C. elegans genome. Some patterns are related to data of public databases such as NCBI. Various patterns are explained from the biological nature, which relates to chromosome structure and protein coding regions. Another well recognised patterns, tandem repetitions composed of satellites, microsatellites and minisatelites are described by spectrograms as well.
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DAK, HAZIRBABA YILDIZ. "IMAGE-BASED MODELING AND PREDICTION OF NON-STATIONARY GROUND MOTIONS." OpenSIUC, 2015. https://opensiuc.lib.siu.edu/dissertations/1008.
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Nonlinear dynamic analysis is a required step in seismic performance evaluation of many structures. Performing such an analysis requires input ground motions, which are often obtained through simulations, due to the lack of sufficient records representing a given scenario. As seismic ground motions are characterized by time-varying amplitude and frequency content, and the response of nonlinear structures is sensitive to the temporal variations in the seismic energy input, ground motion non-stationarities should be taken into account in simulations. This paper describes a nonparametric approach for modeling and prediction of non-stationary ground motions. Using Relevance Vector Machines, a regression model which takes as input a set of seismic predictors, and produces as output the expected evolutionary power spectral density, conditioned on the predictors. A demonstrative example is presented, where recorded and predicted ground motions are compared in time, frequency, and time-frequency domains. Analysis results indicate reasonable match between the recorded and predicted quantities.
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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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Oliveira, Marlice Fernandes de. "Estudo da separação entre voz patológica e normal por meio da avaliação da energia global do sinal de voz." Universidade Federal de Uberlândia, 2007. https://repositorio.ufu.br/handle/123456789/14661.
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Voice analysis is an important tool in the diagnosis of laryngeal disorders. Among distinct
signal processing techniques employed for voice analysis, the spectrogram is commonly used,
as it allows for a visualization of the variation of the energy of the signal as a function of the
both time and frequency. In this context, this study investigates the use of the global energy of
the voice signal, estimated through the spectrogram, as a tool for discrimination between
signals obtained from healthy and pathological subjects. This research has also exploited the
potential use of the global energy of the voice signal to discriminate distinct laryngeal
disorders. In total, 94 subjets were involved in this study, from which 46 were dysphonic and
48 normal. The diagnosis of laryngeal disorders was confirmed by means of a
videolaryngoscopic examination. Participants were also subjected to a clinical examination of
vocal acoustic through the recording of the sustained vowel. The global energy allowed for
the discrimination between normal and disphonic voice. Furthermore, this technique could
discriminate the voice signal of patients suffering from left vocal fold paralysis from those
suffering from other investigated disorders. The results suggest the global energy of the signal
as an auxiliary and alternative tool for the diagnosis between normal and dysphonic voice.A análise do sinal de voz é uma ferramenta importante no diagnóstico dos distúrbios laríngeos. Dentre as diversas técnicas para o processamento da voz destaca-se o espectrograma por permitir uma visualização da variação da energia do sinal em função do tempo e freqüência. Neste contexto, esta pesquisa investiga a energia global do sinal de voz, estimada a partir do espectrograma, como ferramenta capaz de discriminar esses sinais, obtidos de pacientes com diferentes doenças, daqueles coletados de sujeitos saudáveis. O estudo ainda verifica a possibilidade do uso da energia global na discriminação de distúrbios laríngeos. No total 94 indivíduos participaram desse estudo, sendo 46 disfônicos e 48 eufônicos. Inicialmente os sujeitos foram submetidos a um exame de videolaringoscopia para a determinaçãoção do diagnóstico. Posteriormente eles foram submetidos a um exame clínico de análise acústica vocal por meio da gravação da vogal sustentada. Utilizando a energia global foi possível discriminar as vozes normais das vozes disfônicas. Por meio da energia global foi possível ainda separar as vozes de pacientes portadores de paralisia da prega vocal esquerda de todas as outras doenças laríngeas investigadas. Podemos sugerir a energia global da voz como uma ferramenta auxiliar no diagnóstico diferencial entre vozes normais e disfônicas.
Mestre em Ciências
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Ford, George Harold. "Spoken Language Identification from Processing and Pattern Analysis of Spectrograms." NSUWorks, 2014. http://nsuworks.nova.edu/gscis_etd/152.
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Prior speech and linguistics research has focused on the use of phonemes recognition in speech, and their use in formulation of recognizable words, to determine language identification. Some languages have additional phoneme sounds, which can help identify a language; however, most of the phonemes are common to a wide variety of languages. Legacy approaches recognize strings of phonemes as syllables, used by dictionary queries to see if a word can be found to uniquely identify a language.
This dissertation research considers an alternative means of determining language identification of speech data based solely on analysis of frequency-domain data. An analytical approach to speech language identification by three comparative techniques is performed. First, a character-based pattern analysis is performed using the Rix and Forster algorithm to replicate their research on language identification. Second, techniques of phoneme recognition and their relative pattern of occurrence in speech samples are measured for performance in ability for language identification using the Rix and Forster approach. Finally, an experiment using statistical analysis of time-ensemble frequency spectrum data is assessed for its ability to establish spectral patterns for language identification, along with performance. This novel approach is applied to spectrogram audio data using pattern analysis techniques for language identification. It applies the Rix and Forster method to the ensemble of spectral frequencies used over the duration of a speech waveform. This novel approach is compared to the applications of the Rix and Forster algorithm to character-based and phoneme symbols for language identification on the basis of statistical accuracy, processing time requirements, and spatial processing resource needs. The audio spectrum analysis also demonstrates the ability to perform speaker identification using the same techniques performed for language identification.
The results of this research demonstrate the efficacy of audio frequency-domain pattern analysis applied to speech waveform data. It provides an efficient technique in language identification without reliance upon linguistic approaches using phonemes or word derivations. This work also demonstrates a quick, automated means by which information gatherers, travelers, and diplomatic officials might obtain rapid language identification supporting time-critical determination of appropriate translator resource needs.
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TAECHAWATTANANANT, PASRAWIN. "Peak identification and quantification in proteomic mass spectrograms using non-negative matrix factorization." Doctoral thesis, Kyoto University, 2020. http://hdl.handle.net/2433/253496.
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京都大学0048
新制・課程博士
博士(薬科学)
甲第22651号
薬科博第123号
新制||薬科||13(附属図書館)
京都大学大学院薬学研究科薬科学専攻
(主査)教授 石濱 泰, 教授 緒方 博之, 教授 馬見塚 拓, 教授 山下 富義
学位規則第4条第1項該当
Doctor of Pharmaceutical Sciences
Kyoto University
DFAM
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Movin, Andreas, and Jonathan Jilg. "Kan datorer höra fåglar?" Thesis, KTH, Skolan för teknikvetenskap (SCI), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254800.
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Ljudigenkänning möjliggörs genom spektralanalys, som beräknas av den snabba fouriertransformen (FFT), och har under senare år nått stora genombrott i samband med ökningen av datorprestanda och artificiell intelligens. Tekniken är nu allmänt förekommande, i synnerhet inom bioakustik för identifiering av djurarter, en viktig del av miljöövervakning. Det är fortfarande ett växande vetenskapsområde och särskilt igenkänning av fågelsång som återstår som en svårlöst utmaning. Även de främsta algoritmer i området är långt ifrån felfria. I detta kandidatexamensarbete implementerades och utvärderades enkla algoritmer för att para ihop ljud med en ljuddatabas. En filtreringsmetod utvecklades för att urskilja de karaktäristiska frekvenserna vid fem tidsramar som utgjorde basen för jämförelsen och proceduren för ihopparning. Ljuden som användes var förinspelad fågelsång (koltrast, näktergal, kråka och fiskmås) så väl som egeninspelad mänsklig röst (4 unga svenska män). Våra resultat visar att framgångsgraden normalt är 50–70%, den lägsta var fiskmåsen med 30% för en liten databas och den högsta var koltrasten med 90% för en stor databas. Rösterna var svårare för algoritmen att särskilja, men de hade överlag framgångsgrader mellan 50% och 80%. Dock gav en ökning av databasstorleken generellt inte en ökning av framgångsgraden. Sammanfattningsvis visar detta kandidatexamensarbete konceptbeviset bakom fågelsångigenkänning och illustrerar såväl styrkorna som bristerna av dessa enkla algoritmer som har utvecklats. Algoritmerna gav högre framgångsgrad än slumpen (25%) men det finns ändå utrymme för förbättring eftersom algoritmen vilseleddes av ljud av samma frekvenser. Ytterligare studier behövs för att bedöma den utvecklade algoritmens förmåga att identifiera ännu fler fåglar och röster.Sound recognition is made possible through spectral analysis, computed by the fast Fourier transform (FFT), and has in recent years made major breakthroughs along with the rise of computational power and artificial intelligence. The technology is now used ubiquitously and in particular in the field of bioacoustics for identification of animal species, an important task for wildlife monitoring. It is still a growing field of science and especially the recognition of bird song which remains a hard-solved challenge. Even state-of-the-art algorithms are far from error-free. In this thesis, simple algorithms to match sounds to a sound database were implemented and assessed. A filtering method was developed to pick out characteristic frequencies at five time frames which were the basis for comparison and the matching procedure. The sounds used were pre-recorded bird songs (blackbird, nightingale, crow and seagull) as well as human voices (4 young Swedish males) that we recorded. Our findings show success rates typically at 50–70%, the lowest being the seagull of 30% for a small database and the highest being the blackbird at 90% for a large database. The voices were more difficult for the algorithms to distinguish, but they still had an overall success rate between 50% and 80%. Furthermore, increasing the database size did not improve success rates in general. In conclusion, this thesis shows the proof of concept and illustrates both the strengths as well as short-comings of the simple algorithms developed. The algorithms gave better success rates than pure chance of 25% but there is room for improvement since the algorithms were easily misled by sounds of the same frequencies. Further research will be needed to assess the devised algorithms' ability to identify even more birds and voices.
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Piascik, A. S. "A spectrograph for the rapid analysis of transients and classification of supernovae." Thesis, Liverpool John Moores University, 2017. http://researchonline.ljmu.ac.uk/7152/.
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This thesis describes the design, construction and characterisation of a spectrograph operating in the optical range 4000-8000 Å and its application in the observation and classification of transient astronomical sources.
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Holsclaw, Greg M. "The MESSENGER Visible and Infrared Spectrograph: Design, calibration, and analysis of lunar observations." Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3207780.
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Doan, Duy Anh N. "Analysis of magnetic activity cycles in solar analogs using Solar - Stellar Spectrograph data." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/114106.
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Thesis: S.B., Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 30-31).
The Solar-Stellar Spectrograph (SSS) Project includes frequent observations of 30 - 50 Sun-like stars to address a wide variety of questions regarding the nature of stellar magnetic activity cycles. The magnetic activity cycles of 18 stars in the SSS project are analyzed using the Lomb Scargle method of least-squares spectral analysis. Periodograms reveal that out of 18 stars, 9 stars have one magnetic cycle and 6 stars have two magnetic cycles, with periods ranging from 2 years to 17 years. The remaining stars show significant variability but without pronounced periodicity. Most of the detected cycles have a false alarm probability (FAP) well below 10-3 The results for a number of stars are compared and confirmed with earlier observations by Mount Wilson Observatory's project, published by Baliunas et. al. (1995). Four more stars are added to the plot of activity cycle period - rotational period relation by Bohm-Vitense (2006), and they all lie on either the active sequence or the inactive sequence. This result, together with the fact that several stars have two different cycles lying on different sequences, lends more evidence to the hypothesis that stars have multiple dynamos but are dominated by one of them.
by Duy Anh N. Doan.
S.B.
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Hymas, Hewitt M. "A calibration of the Naval Postgraduate School middle ultraviolet spectrograph and an analysis of the OII 2470 Å emission obtained by the middle ultraviolet spectrograph /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA283449.
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Hymas, Hewitt M. "A calibration of the Naval Postgraduate School middle ultraviolet spectrograph and an analysis of the OII 2470 ΩA emission obtained by the middle ultraviolet spectrograph." Thesis, Monterey, California. Naval Postgraduate School, 1994. http://hdl.handle.net/10945/28021.
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The NPS middle ultraviolet spectrograph, MUSTANG, instrument was tested using standard techniques to determine the wavelength calibration and overall sensitivity. The instrument was launched on March 10, 1994 on a NASA sounding rocket from Poker Flats, Alaska. Post-flight calibration indicates the wavelength calibration did not change as a result of the launch and no significant change in the sensitivity calibration. Ultraviolet dayglow spectra of the earth's ionosphere from 1800 A to 3400 A were obtained during a similar launch on March 19, 1992 from White Sands Missile Range, New Mexico. Data were obtained on the downleg of this earlier experiment and range in altitude from 115 km to 320 km. Analysis of the data from 2420 A to 2490 A was conducted to obtain the intensity profile of the OII 2470.4 A multiplet. The analysis used synthetic spectra generated for the N2 Vegard-Kaplan and the nitric-oxide gamma band emissions
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Komonjinda, Siramas. "A study of binary star orbits using precise radial velocity measurements with the HERCULES spectrograph." Thesis, University of Canterbury. Department of Physics and Astronomy, 2008. http://hdl.handle.net/10092/1590.
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Orbits of spectroscopic binary systems have been studied for more than a century. Over three thousand orbits of spectroscopic binary systems have been derived. These orbits are based on the radial velocities measured from the spectra recorded by a photographic plate to a high precision spectrum observed from a modern spectrograph. In many cases, the shape of the orbit was assumed to be circular, of hence the eccentricity is zero. This assumption is based on the fact that a small eccentricity (e < 0.1) measured from the observed data might be a result from the error of observations or from the intrinsic variation of a spectroscopic binary system. Sixteen southern spectroscopic binary systems, including twelve single-lined binaries and four double-lined binaries, were selected to study in this research program. These systems were assumed to have circular orbits or have very nearly circular orbits (e < 0.1) from their previous published solutions. The HERCULES spectrograph was used in conjunction with the 1-m McLellan telescope at Mt John University Observatory to collect the spectra of these systems. The observations, taken from October 2004 to August 2007, comprised about 2000 high-resolution spectra of spectroscopic binary systems and standard radial-velocity stars. Radial velocities of spectroscopic binary systems were measured from these spectra and orbital solutions of the systems were derived from these radial velocities. It was found that from HERCULES data, we are able to achieve high-precision orbital solutions of all the systems studied. The best-fit solutions can be improved as much as 70 times from the literature’s orbital solutions. It has been found that the precision of a system depends on the rotational velocities of the components as well as the level of their chromospheric activity. We are able to confirm the eccentricity in the orbit of only one of the selected spectroscopic binary systems, HD194215. Its eccentricity is 0.123 29 ± 0.000 78. The small eccentricities of other systems are not confirmed. There are four systems; HD22905, HD38099, HD85622 and HD197649, that have circular orbital solutions from the large errors in their measured eccentricities. Two systems, HD77258 and HD124425, have too small eccentricities, e = 0.000 85±0.000 19 and 0.002 60 ± 0.000 99 to be acceptable. An intrinsic variation is a presumed cause of the spurious eccentricities derived from the data of the other eight systems. Photometric data from Mt John University Observatory service photometry program, as well as the photometric data from the Hipparcos satellite and information of these systems from the literature, using various methods and instruments, give a wider view on the systems’ behaviour. It is possible that the spurious eccentricities derived for these systems result from the eclipsing behaviour of a system (HD50337), or from the nature of the components, such as, the distortion of their shape (HD352 and HD136905), their chromospheric activity (HD9053, HD3405, HD77137, HD101379 and HD155555), or stellar pulsation (HD30021). Models of the active chromosphere system, HD101379, have been simulated. An analysis of synthetic radial velocity data shows that spots on the star’s photosphere can cause a spurious eccentricity. The values of the spurious eccentricity and the longitude of periastron are dependent on the spot size, the spot temperature, and the position of the spots.
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Roberts, Geoff. "Classification of non-stationary signals using time-frequency representations and multiple hypotheses tests : an application to humpback whale songs." Thesis, Queensland University of Technology, 1999.
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Truskinger, Anthony M. "Semi-automated annotation of environmental acoustic recordings." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/84543/8/Anthony_Truskinger_Thesis.pdf.
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Environmental sensors collect massive amounts of audio data. This thesis investigates computational methods to support human analysts in identifying faunal vocalisations from that audio. A series of experiments was conducted to trial the effectiveness of novel user interfaces. This research examines the rapid scanning of spectrograms, decision support tools for users, and cleaning methods for folksonomies. Together, these investigations demonstrate that providing computational support to human analysts increases their efficiency and accuracy; this allows bioacoustics projects to efficiently utilise their valuable human analysts.
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Marron, Antony C. "An analysis of ionospheric dayglow from observations of the Naval Postgraduate School Middle Ultraviolet Spectrograph (MUSTANG)." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1993. http://handle.dtic.mil/100.2/ADA277351.
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Mack, Bryan D. "An analysis of middle ultraviolet emissions of molecular nitrogen and nitric oxide and vacuum calibration of an ultraviolet spectrograph." Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/43747.
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Approved for public release; distribution is unlimitedUltraviolet emissions from the earth's ionosphere in the wavelength range 1850 A to 2070 A are analyzed. Specifically, thirteen Lyman-Birge-Hopfield (LBH) band emissions from molecular nitrogen (N2) and the gamma,delta and epsilon bands of nitric oxide (N
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Pethiyagoda, Ravindra. "Mathematical and computational analysis of Kelvin ship wave patterns." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/101167/1/Ravindra_Pethiyagoda_Thesis.pdf.
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This thesis concerns the form of water wave patterns generated by an idealised ship moving steadily through still water. An efficient numerical scheme for computing these waves with much finer detail than ever before is developed, and the results are used to determine the effect that certain properties, such as the ship's speed and dimensions, have on ship wakes. Two features are used to characterise the ship wave: the ship's apparent wake angle, the half-angle of the characteristic v-pattern of a ship wave, and a spectrogram produced by applying time-frequency analysis to a cross-section of the ship wave.
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Semela, René. "Automatické tagování hudebních děl pomocí metod strojového učení." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-413253.
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One of the many challenges of machine learning are systems for automatic tagging of music, the complexity of this issue in particular. These systems can be practically used in the content analysis of music or the sorting of music libraries. This thesis deals with the design, training, testing, and evaluation of artificial neural network architectures for automatic tagging of music. In the beginning, attention is paid to the setting of the theoretical foundation of this field. In the practical part of this thesis, 8 architectures of neural networks are designed (4 fully convolutional and 4 convolutional recurrent). These architectures are then trained using the MagnaTagATune Dataset and mel spectrogram. After training, these architectures are tested and evaluated. The best results are achieved by the four-layer convolutional recurrent neural network (CRNN4) with the ROC-AUC = 0.9046 ± 0.0016. As the next step of the practical part of this thesis, a completely new Last.fm Dataset 2020 is created. This dataset uses Last.fm and Spotify API for data acquisition and contains 100 tags and 122877 tracks. The most successful architectures are then trained, tested, and evaluated on this new dataset. The best results on this dataset are achieved by the six-layer fully convolutional neural network (FCNN6) with the ROC-AUC = 0.8590 ± 0.0011. Finally, a simple application is introduced as a concluding point of this thesis. This application is designed for testing individual neural network architectures on a user-inserted audio file. Overall results of this thesis are similar to other papers on the same topic, but this thesis brings several new findings and innovations. In terms of innovations, a significant reduction in the complexity of individual neural network architectures is achieved while maintaining similar results.
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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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Andersen, Carl K. "A calibration of the Naval Postgraduate School Middle Ultraviolet Spectrograph and an analysis of the OII 2470 Å and OI 2972 Å emissions obtained from mid-latitude rocket observations." Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA240686.
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Thesis (M.S. in Physics)--Naval Postgraduate School, September 1990.Thesis Advisor(s): Cleary, David D. Second Reader: Gnanalingam, Suntharalingam. "September 1990." Description based on title screen viewed on December 16, 2009. DTIC Descriptor(s): Airglow, ultraviolet spectra, emission, ionosphere, layers, intensity, theses, emission spectra, oxygen, profiles, flight, patterns, calibration, earth(planet), rockets, sounding rockets, temperate regions, line spectra, rocket research, test and evaluation, frequency. DTIC Identifier(s): Fastie spectrograph, dayglow. Author(s) subject terms: Ebert-Fastie Spectrograph, ultraviolet spectra, dayglow; OII 2770 Å multiplet; OI 2972 Å line emission. Includes bibliographical references (p. 108-109 ). Also available in print.
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Andersen, Carl K. "A calibration of the Naval Postgraduate School Middle Ultraviolet Spectrograph and an analysis of the OII 2470 ΩA and OI 2972 ΩA emissions obtained from mid-latitude rocket observations." Thesis, Monterey, California: Naval Postgraduate School, 1990. http://hdl.handle.net/10945/34866.
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Approved for public release; distribution unlimited.The MUSTANG instrument was calibrated using standard techniques to determine the sensitivity and wavelength calibrations and field of view. The instrument was launched aboard a NASA sounding rocket on March 30, 1990. Post- flight tests indicated that the calibration did not change as a result of the rocket experiment. Ultraviolet dayglow spectra of the Earth's ionosphere were obtained from approximately 100 km to 320 km in altitude over a wavelength range of 1800 A to 3400 A. The spectra were divided into 512 pixels of approximately 3.134 A per pixel. Analyses of the data from 2420 A to 2490 A and from 2920 A to 2972 A were conducted to obtain the intensity profiles of the OII 2470.4 A multiplet and the OI 2972.3 A line emission, respectively. The intensity profile of the OII 2470.4 A multiplet was found to have a broad peak of 1.6 kR centered at approximately 250 km. The intensity profile of the OI 2972.3 A line emission shows a general trend of decreasing intensity with altitude. The maximum intensity of 3.6 kR was found at 105 km and the minimum of 137 R at 315 km. A partial layer, with an intensity of 4.1 kR, was evident near 150 km.
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Liao, Wen-Chien, and 廖文劍. "A Noninvasive Method for 3D-Spectrogram Entropy Analysis of the Autonomic Nervous System." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/94687411768173577672.
Full textAbstract:
博士國立臺灣大學
醫學工程學研究所
99
The purpose of this study was to establish a complete system for electrophysiological diagnosis based on the autonomic nervous system. This study focused on overactive bladder syndrome as we recorded and analyzed the peripheral nervous system of the urinary bladder. Method: The impulses of the peripheral nervous system were recorded during micturition. Electrophysiological data were used for early diagnosis and prognosis after treatment in an early stage multichannel study. Materials include an improvised non-invasive electrode, double antennae, a filter, an analog-to-digital conversion card, a multifrequency stimulator, and a time frequency and neuroentrophy analysis program. A program was developed for recording, analysis, diagnosis, treatment selection, and prognosis. The data were analyzed to develop a theorem based on the study of overactive bladder. Conclusion: We can diagnosis and treat various dysfunctions of the autonomic nervous system. Sympathetic and parasympathetic neural impulses are passed through a band filter where the action potentials are quantified. Using parameters like average cycles, stimulus frequency, spatial sampling interval, and temporal sampling interval, we can isolate a specific neural impulse for study. This method can help us evaluate the status of different organ systems and determine appropriate treatments based on an early prognostic value derived from studies of appropriate treatments based on an early prognostic value derived from studies of autonomic neural electrophysiology.
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Aragonda, Haricharan. "Demodulation of Narrowband Speech Spectrograms." Thesis, 2014. http://hdl.handle.net/2005/2777.
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Speech is a non-stationary signal and contains modulations in both spectral and temporal domains. Based on the type of modulations studied, most speech processing algorithms can be classified into short-time analysis algorithms, narrow-band analysis algorithms, or joint spectro-temporal analysis algorithms. While traditional methods of speech analysis study the modulation along either time (Short-time analysis algorithms) or frequency (Narrowband analysis) at a time. A new class of algorithms that work simultaneously along both temporal as well as spectral dimensions, called the spectro-temporal analysis algorithms, have become prominent over the past decade.
Joint spectro-temporal analysis (also referred to as 2-D speech analysis) has shown promise in applications such as formant estimation, pitch estimation, speech recognition, etc.
Over the past decade, 2-D speech analysis has been independently motivated from several directions. Broadly these motivations for 2-D speech models can be grouped into speech-production motivated, source-separation/machine- learning motivated and neurophysiology motivated.
In this thesis, we develop 2-D speech model based on the speech production motivation. The overall organization of the thesis is as follows: We first develop the context of 2-D speech processing in Chapter one, we then proceed to develop a 2-D multicomponent AM-FM model for narrowband spectrogram patch of voiced speech and experiment with the perceptual significance of number of components needed to represent a spectrogram patch in Chapter two. In Chapter three we develop a demodulation algorithm called the inphase and the quadrature phase demodulation (IQ), compared to the state-of-the art sinusoidal demodulation, the AM obtained using this method is more robust to carrier estimation errors. The demodulation algorithm was verified on call voiced sentences taken from the TIMIT database. In chapter four we develop a demodulation algorithm based on Riesz transform, a natural extension of the Hilbert transform to higher dimensions, unlike the sinusoidal and the IQ demodulation techniques, Riesz-transform-based demodulation does not require explicit carrier estimation and is also robust to pitch discontinuous in patches. The algorithm was validated on all voiced sentences from the TIMIT database. Both IQ and Riesz-transform-based methods were found to give more accurate estimates of the 2-D AM (relates to vocal tract) and 2-D carrier (relates to source) compared with the sinusoidal modulation. In Chapter five we show application of the demodulated AM and carrier to pitch estimation and for creation of hybrid sounds. The hybrid sounds created were found to have better perceptual quality compared with their counterparts created using the linear prediction analysis. In Chapter six we summarize the work and present with possible directions of future research.
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Tung, Chia-Chun, and 董家濬. "The echo statistics and spectrogram analysis of field-aligned irregularities in the ionospheric E region by using the Chung-Li VHF radar." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/58297533684798441917.
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碩士國立中央大學
太空科學研究所
86
The observations and statistics of field-aligned irregularities in the midlatitude ionospheric E region were made by using the Chung-Li VHF radar.Investigation of occurrence frequency of radar returns shows that the irregularities were most frequently observed in July and Auguest and less active in November and December.Futhermore,these echoes were almost appeared in the night-time period of 19-04LT and located at a altitude range-height of about 100-110km. Two events associated with type-I irregularities with upward and downward electron drift motions have been observed,respectivity.The occurrence of type-I irregularities is comparatively rare in the midlatitude E region.The results shown in this paper indicate that the large electric fields can be generated by the same polarization mechanism as those at the magnetic equator.The generated polarization fields are greater than the ambient electric fields and sufficient to excite the two-stream instability corresponding to our observation.
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Duan, Xiao. "The Fractional Fourier Transform and Its Application to Fault Signal Analysis." Thesis, 2012. http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11207.
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To a large extent mathematical transforms are applied on a signal to uncover information that is concealed, and the capability of such transforms is valuable for signal processing. One such transforms widely used in this area, is the conventional Fourier Transform (FT), which decomposes a stationary signal into different frequency components. However, a major drawback of the conventional transform is that it does not easily render itself to the analysis of non-stationary signals such as a frequency modulated (FM) or amplitude modulated (AM) signal. The different frequency components of complex signals cannot be easily distinguished and separated from one another using the conventional FT. So in this thesis an innovative mathematical transform, Fractional Fourier Transform (FRFT), has been considered, which is more suitable to process non-stationary signals such as FM signals and has the capability not only of distinguishing different frequency components of a multi-component signal but also separating them in a proper domain, different than the traditional time or frequency domain.
The discrete-time FRFT (DFRFT) developed along with its derivatives, such as Multi-angle-DFRFT (MA-DFRFT), Slanted Spectrum and Spectrogram Based on Slanted Spectrum (SBSS) are tools belonging to the same FRFT family, and they could provide an effective approach to identify unknown signals and distinguish the different frequency components contained therein. Both artificial stationary and FM signals have been researched using the DFRFT and some derivative tools from the same family. Moreover, to accomplish a contrast with the traditional tools such as FFT and STFT, performance comparisons are shown to support the DFRFT as an effective tool in multi-component chirp signal analysis. The DFRFT taken at the optimum transform order on a single-component FM signal has provided higher degree of signal energy concentration compared to FFT results; and the Slanted Spectrum taken along the slant line obtained from the MA-DFRFT demonstration has shown much better discrimination between different frequency components of a multi-component FM signal.
As a practical application of these tools, the motor current signal has been analyzed using the DFRFT and other tools from FRFT family to detect the presence of a motor bearing fault and obtain the fault signature frequency. The conclusion drawn about the applicability of DFRFT and other derivative tools on AM signals with very slowly varying FM phenomena was not encouraging. Tools from the FRFT family appear more effective on FM signals, whereas AM signals are more effectively analyzed using traditional methods like spectrogram or its derivatives. Such methods are able to identify the signature frequency of faults while using less computational time and memory.
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WU, SHUO-REN, and 吳碩仁. "A Mandarin syllable features analysis on spectrograms." Thesis, 1990. http://ndltd.ncl.edu.tw/handle/54155600593409481924.
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Stegman, Kelly J. "Towards detection of user-intended tendon motion with pulsed-wave Doppler ultrasound for assistive hand exoskeleton applications." Thesis, 2009. http://hdl.handle.net/1828/1699.
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Current bio-robotic assistive devices have developed into intelligent and dexterous machines. However, the sophistication of these wearable devices still remains limited by the inherent difficulty in controlling them by sensing user-intention. Even the most commonly used sensing method, which detects the electrical activity of skeletal muscles, offer limited information for multi-function control. An alternative bio-sensing strategy is needed to allow for the assistive device to bear more complex functionalities. In this thesis, a different sensing approach is introduced using Pulsed-Wave Doppler ultrasound in order to non-invasively detect small tendon displacements in the hand. The returning Doppler shifted signals from the moving tendon are obtained with a new processing technique. This processing technique involves a unique way to acquire raw data access from a commercial clinical ultrasound machine and to process the signal with Fourier analysis in order to determine the tendon displacements. The feasibility of the proposed sensing method and processing technique is tested with three experiments involving a moving string, a moving biological beef tendon and a moving human hand tendon. Although the proposed signal processing technique will be useful in many clinical applications involving displacement monitoring of biological tendons, its uses are demonstrated in this thesis for ultrasound-based user intention analysis for the ultimate goal of controlling assistive exoskeletal robotic hands.