Dissertations / Theses on the topic 'Hilbert transform'
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Cervi, Jacopo. "Hilbert transform." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/7466/.
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The Hilbert transform is an important tool in both pure and applied mathematics. It is largely used in the field of signal processing. Lately has been used in mathematical finance as the fast Hilbert transform method is an efficient and accurate algorithm for pricing discretely monitored barrier and Bermudan style options.
The purpose of this report is to show the basic properties of the Hilbert transform and to check the domain of definition of this operator.
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Husin, Axel. "The Hilbert Transform." Thesis, Uppsala universitet, Analys och tillämpad matematik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-200442.
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Barnhart, Bradley Lee. "The Hilbert-Huang Transform: theory, applications, development." Diss., University of Iowa, 2011. https://ir.uiowa.edu/etd/2670.
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Hilbert-Huang Transform (HHT) is a data analysis tool, first developed in 1998, which can be used to extract the periodic components embedded within oscillatory data. This thesis is dedicated to the understanding, application, and development of this tool. First, the background theory of HHT will be described and compared with other spectral analysis tools. Then, a number of applications will be presented, which demonstrate the capability for HHT to dissect and analyze the periodic components of different oscillatory data. Finally, a new algorithm is presented which expands HHT ability to analyze discontinuous data. The sum result is the creation of a number of useful tools developed from the application of HHT, as well as an improvement of the HHT tool itself.
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Li, Xiaochun. "Uniform bounds for the bilinear Hilbert transforms /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3025634.
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Ariyani, Mathematics & Statistics Faculty of Science UNSW. "The generalized continuous wavelet transform on Hilbert modules." Publisher:University of New South Wales. Mathematics & Statistics, 2008. http://handle.unsw.edu.au/1959.4/42151.
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The construction of the generalized continuous wavelet transform (GCWT) on Hilbert spaces is a special case of the coherent state transform construction, where the coherent state system arises as an orbit of an admissible vector under a strongly continuous unitary representation of a locally compact group. In this thesis we extend this construction to the setting of Hilbert C*-modules. In particular, we define a coherent state transform and a GCWT on Hilbert modules. This construction gives a reconstruction formula and a resolution of the identity formula analogous to those found in the Hilbert space setting. Moreover, the existing theory of standard normalized tight frames in finite countably generated Hilbert modules can be viewed as a discrete case of this construction We also show that the image space of the coherent state transform on Hilbert module is a reproducing kernel Hilbert module. We discuss the kernel and the intertwining property of the group coherent state transform.
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Navarro, Moisés M. "Ocean wave data analysis using Hilbert transform techniques." Thesis, Monterey, California. Naval Postgraduate School, 1996. http://hdl.handle.net/10945/32022.
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A novel technique to determine the phase velocity of long-wavelength shoaling waves is investigated. Operationally, the technique consists of three steps. First, using the Hilbert transform of a time series, the phase of the analytic signal is determined. Second, the correlations of the phases of analytic signals between two points in space are calculated and an average time of travel of the wave fronts is obtained. Third, if directional spectra are available or can be determined from time series of large array of buoys, the angular information can be used to determine the true time of travel. The phase velocity is obtained by dividing the distance between buoys by the correlation time. Using the Hilbert transform approach, there is no explicit assumption of the relation between frequency and wavenumber of waves in the wave field, indicating that it may be applicable to arbitrary wave fields, both linear and nonlinear. Limitations of the approach are discussed.
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Eftekhar, Amir. "Hilbert-Huang transform : biosignal analysis and practical implementation." Thesis, Imperial College London, 2010. http://hdl.handle.net/10044/1/5991.
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Any system, however trivial, is subjected to data analysis on the signals it produces. Over the last 50 years the influx of new techniques and expansions of older ones have allowed a number of new applications, in a variety of fields, to be analysed and to some degree understood. One of the industries that is benefiting from this growth is the medical field and has been further progressed with the growth of interdisciplinary collaboration. From a signal processing perspective, the challenge comes from the complex and sometimes chaotic nature of the signals that we measure from the body, such as those from the brain and to some degree the heart. In this work we will make a contribution to dealing with such systems, in the form of a recent time-frequency data analysis method, the Hilbert-Huang Transform (HHT), and extensions to it. This thesis presents an analysis of the state of the art in seizure and heart arrhythmia detection and prediction methods. We then present a novel real-time implementation of the algorithm both in software and hardware and the motivations for doing so. First, we present our software implementation, encompassing realtime capabilities and identifying elements that need to be considered for practical use. We then translated this software into hardware to aid real-time implementation and integration. With these implementations in place we apply the HHT method to the topic of epilepsy (seizures) and additionally make contributions to heart arrhythmias and neonate brain dynamics. We use the HHT and some additional algorithms to quantify features associated with each application for detection and prediction. We also quantify significance of activity in such a way as to merge prediction and detection into one framework. Finally, we assess the real-time capabilities of our methods for practical use as a biosignal analysis tool.
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Hollenbeck, Brian. "Best constants for operators involving the Hilbert transform /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3012977.
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Liu, Yue Lin. "The linear canonical transform and generalized hilbert transform with applications in signal processing." Thesis, University of Macau, 2009. http://umaclib3.umac.mo/record=b2100798.
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Agora, Elona. "Boundedness of the Hilbert Transform on Weighted Lorentz Spaces." Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/108930.
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The main goal of this thesis is to characterize the weak-type (resp. strong-type) boundedness of the Hilbert transform H on weighted Lorentz spaces Λpu(w). The characterization is given in terms of some geometric conditions on the weights u and w and the weak-type (resp. strong-type) boundedness of the Hardy-Littlewood maximal operator on the same spaces. Our results extend and unify simultaneously the theory of the boundedness of H on weighted Lebesgue spaces Lp(u) and Muckenhoupt weights Ap, and the theory on classical Lorentz spaces Λp(w) and Ariño-Muckenhoupt weights Bp.Títol: Acotaciò de l'operador de Hilbert sobre espais de Lorentz amb pesos Resum: L'objectiu principal d'aquesta tesi es caracteritzar l'acotació de l'operador de Hilbert sobre els espais de Lorentz amb pesos Λpu(w). També estudiem la versió dèbil. La caracterització es dona en terminis de condicions geomètriques sobre els pesos u i w, i l'acotació de l'operador maximal de Hardy-Littlewood sobre els mateixos espais. Els nostres resultats unifiquen dues teories conegudes i aparentment no relacionades entre elles, que tracten l'acotació de l'operador de Hilbert sobre els espais de Lebegue amb pesos Lp(u) per una banda i els espais de Lorentz clàssics Λp(w) per altre banda.
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Guan, Li Min. "Hilbert transform characterization of boundary values of H2 functions." Thesis, University of Macau, 2005. http://umaclib3.umac.mo/record=b1447322.
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McKain, David. "Transference and the Hilbert transform on Banach function spaces." Thesis, University of Edinburgh, 2000. http://hdl.handle.net/1842/12628.
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The thesis begins with a summary of the classical theory of Banach function spaces, including the notions of saturation and associate norms along with the various well-known ideas of completeness. We then go on to establish some rather more "practical" results. In particular we look at the problem of establishing when certain subspaces, such as the simple or continuous functions, are dense in a Banach function space Lp. We shall see that our intention fails us slightly when considering continuous functions, requiring us to approach that idea of saturation from a slightly different angle. This interplay between topology, measure and norm is studied in more depth when we look at function norms over locally compact abelian groups, and results will be illuminated by reviewing well-known functions spaces such as Lorentz spaces and weighted Lp spaces. The chapter finishes with the idea of vector-valued function spaces. In the second chapter we motivate and develop the idea of mixed (or iterated) norms, as introduced for Lp spaces by Benedek and Panzone, before going on to identify dense subspaces and some other elementary results. We shall see that there are certain interesting measurability problems to address here which are not evident when considering Lp spaces. One rather technical highlight of this measure theory will be to make rigorous the canonical identification between most mixed norm spaces and vector-valued Banach function spaces. Motivated by a trivial application of Fubini's theorem which allows us to interchange two Lp norms, i.e. ||||f(x, y)||Lp(dy)||Lp(dx) = ||||f(x, y)||Lp(dx)||Lp(dy), we then consider when interchanging two general mixed norms is bounded. Although there are some positive results we shall see that this idea fails in many cases. In particular we shall show that two iterated Lorentz Lpq norms can be interchanged if and only if p = q. In chapter three we study how the classical transference theorem of Coifman and Weiss can be generalised from Lp spaces to arbitrary rearrangement invariant spaces.
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Zhang, Dan. "Multiscale analysis by nonseparable wavelet and Hilbert-Huang transform." HKBU Institutional Repository, 2012. https://repository.hkbu.edu.hk/etd_ra/1411.
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Klingspor, Måns. "Hilbert Transform : Mathematical Theory and Applications to Signal processing." Thesis, Linköpings universitet, Matematik och tillämpad matematik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-122736.
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The Hilbert transform is a widely used transform in signal processing. In this thesis we explore its use for three different applications: electrocardiography, the Hilbert-Huang transform and modulation. For electrocardiography, we examine how and why the Hilbert transform can be used for QRS complex detection. Also, what are the advantages and limitations of this method? The Hilbert-Huang transform is a very popular method for spectral analysis for nonlinear and/or nonstationary processes. We examine its connection with the Hilbert transform and show limitations of the method. Lastly, the connection between the Hilbert transform and single-sideband modulation is investigated.
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Williams, Christopher Paul. "Application of Hartley and Hilbert transforms in Fourier transform ion cyclotron resonance mass spectrometry /." The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487760357822985.
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Khadapkar, Shailesh Sunil. "Failure identification of gear systems using Hilbert-Huang transform and artificial neural networks." Diss., Online access via UMI:, 2006.
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Zemmour, Arnaud I. "The Hilbert-Huang transform for damage detection in plate structures." College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/3832.
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Thesis (M.S.) -- University of Maryland, College Park, 2006.Thesis research directed by: Dept. of Aerospace Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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EREMENKO, Vladimir, Iuliia LYSENKO, Anatoliy PROTASOV, and Evgeniy SUSLOV. "Using Hilbert Transform for Signal Processing in Mechanical Impedance Analysis." Thesis, 19th World Conference on Non-Destructive Testing, 2016. http://er.nau.edu.ua/handle/NAU/21998.
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These papers describe using of Hilbert transform in processing signal
received from standard mechanical impedance sensor. It’s shown that Hilbert
transform allows extract additional information from the signal and increase
reliability of non-destructive testing. Presented mathematical model of typical
signals received form mechanical impedance sensor and described ways to
extraction and using in non-destructive testing process wide known characteristic of
the signal like instantaneous phase and instantaneous frequency. Also described
another parameters based on mentioned characteristics which are more stable in
diagnostic decision-making compare to another widely used in contemporary flow
detectors. Shown experimental results obtained from scanning samples of
composite materials used in development of light-weight aircrafts.
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Souza, Marcelo Gustavo de. "Identificação e caracterização de não-linearidades em dinâmica estrutural." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/18/18149/tde-19012011-120002/.
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Esta dissertação tem como objetivo principal realizar uma investigação sobre técnicas de identificação e caracterização de não linearidades em dinâmica estrutural. Em particular, busca-se aplicar as transformadas de Hilbert e Hilbert-Huang na identificação e caracterização de um sistema estrutural composto de uma viga metálica em balanço com uma massa concentrada em sua extremidade livre e apresentando uma não linearidade cúbica. Este efeito não linear é obtido através de um fio metálico tracionado que é fixo à extremidade livre da viga em balanço. O sistema é modelado através de ferramentas analíticas convencionais e o modelo do sistema é usado em simulações numéricas. Ensaios experimentais de vibração livre são realizados e os sinais medidos são usados como dados de entradas nas transformadas afim de se investigar o fenômeno não linear presente na estrutura. Os resultados simulados numéricamente apresentaram uma excelente correlação com os resultados experimentais no que se refere à identificação e caracterização do efeito não linear cubico presente no sistema. Algumas distorções entre resultados simulados e experimentais foram observados no que se refere à quantificação do parâmetro não linear, mas de forma geral, as técnicas empregadas produziram resultados bastante satisfatórios.The major goal of this dissertation is to investigate currently available techniques to the identification and characterization of nonlinearities in structural dynamics. Particular attention is paid to the application of the Hilbert and Hilbert-Huang transforms in the nonlinearity identification and characterization process. For that purpose, a structural system composed of a steel cantilever beam carrying a lumped mass at its free end is used. The nonlinear effect is introduced by attaching the lumped mass to a thin steel wire that is positioned transversely to the beam\'s longitudinal axis. By varying the traction force on this wire different levels of nonlinearity can be observed on the beam\'s bending motion when it undergoes free vibrations. The system analytical model is obtained by employing standard modeling techniques and this model is used in numerical simulations. An experimental survey is carried out on an actual prototype in order to provide a comparison basis for the numerically simulated results. The output vibration signals resulting from either the numerical simulations and experimental tests are then used with the transform methods studied and the results are compared. A good correlation is observed between numerical and experimental data, what is a clear indication of the robustness of the Hilbert and Hilbert-Huang transforms.
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Kirk, N. E. "The modal analysis of non-linear structures employing the Hilbert transform." Thesis, University of Manchester, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356711.
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Wilson, Julie. "Polar and AC operators, the Hilbert transform, and matrix-weighted shifts." Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/14682.
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Well-bounded operators of type (B) are the building blocks for trigonometrically well-bounded, polar and AC operators. We examine the relationship between polar and AC operators of type (B) and explore the concepts of bounded variation and absolute continuity for functions defined on annuli. In 1973, Hunt, Muckenhoupt and Wheeden showed that the Hilbert transform is a bounded operator on a weighted Lp space precisely when the weight satisfies the Ap condition. This result is proved independently for Lp spaces over the reals, the circle and the integers. We investigate the inter-relationships between these three theorems and show that the theorems for the reals and the integers are equivalent.
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Srinivasa, Murthy Dilip. "REAL-TIME HILBERT TRANSFORM AND AUTOCORRELATION FOR DIGITAL WIDEBAND COMMUNICATION APPLICATIONS." Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1227202325.
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Oliveira, Filho Itamar Sales de. "Time-frequency analysis : The bilinear Hilbert transform and the Carleson theorem." reponame:Repositório Institucional da UFC, 2016. http://www.repositorio.ufc.br/handle/riufc/18888.
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OLIVEIRA FILHO, Itamar Sales de. Time-frequency analysis : the bilinear Hilbert transform and the Carleson theorem. 2016. 109 f. Dissertação (Mestrado em Matemática em Rede Nacional) – Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2016.Submitted by Rocilda Sales (rocilda@ufc.br) on 2016-08-03T13:04:26Z No. of bitstreams: 1 2016_dis_isoliveirafilho.pdf: 1052932 bytes, checksum: 65cea71bb69c14d263414a81de75c8d8 (MD5)
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In 1966, Lennart Carleson proved that the Fourier series of a periodic function, square integrable over a fundamental domain of the real line converges to the same function almost everywhere. This result was revisited years later by Charles Fe erman (1973) and by Lacey and Thiele (2000). It is studied here Lacey and Thiele's work, where they approached the problem through time-frequency analysis. This proof was inspired in a previous work of theirs, where they establish boundedness for the bilinear Hilbert transform in Lebesgue spaces. The study of boundedness for this operator started with the attempts to establish boundedness for the first Calderon's commutator. Also through time-frequency analysis, it will be studied one of the works of Lacey and Thiele about the bilinear Hilbert transform.
Em 1966, Lennart Carleson provou que a série de Fourier de uma função periódica, quadrado-integrável em um domínio fundamental na reta converge para a prápria função em quase todo ponto. Esse resultado foi revisitado alguns anos depois por Charles Fefferman (1973) e por Lacey e Thiele (2000). É estudado aqui o trabalho desses ultimos, onde o problema é abordado através de análise de tempo e frequência. Essa demonstração foi inspirada em um trabalho anterior dos mesmos autores em que estabelecem limitação para a transformada de Hilbert bilinear em espaços de Lebesgue. O estudo da limitação desse operador começou com as tentativas de estabelecer limitação para o primeiro comutador de Calderón. Também sob o ponto de vista da análise de tempo e frequência, será estudado um dos trabalhos de Lacey e Thiele sobre a transformada de Hilbert bilinear.
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Tuleja, Peter. "Využití Hilbert Huangovy transformace pro analýzu nestacionárních signálů z fyzikálních experimentů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220614.
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This paper discusses the possible use of Hilbert-Huang transform to analyze the data obtained from physical experiments. Specifically for the analysis of acoustic emission in the form of acoustic shock. The introductory section explains the concept of acoustic emission and its detection process. Subsequently are discussed methods for signal analysis in time-frequency domain. Specifically, short-term Fourier transform, Wavelet transform, Hilbert transform and Hilbert-Huang transform. The final part contains the proposed method for measuring the performance and accuracy of different approaches.
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Ayenu-Prah, Albert Yawson Jr. "Empirical mode decomposition and civil infrastructure systems." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 210 p, 2008. http://proquest.umi.com/pqdweb?did=1456291101&sid=1&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Paolantoni, Thibault. "Application de Riemann-Hilbert-Birkhoff." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS410/document.
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L'application exponentielle duale est une façon d'encoder les matrices de Stokes d'une connexion sur un fibré trivial sur la sphère de Riemann avec deux pôles : un pôle double en 0 et un pôle simple en l'infini.On donne ici une formule pour l'application exponentielle duale comme une série formelle non commutative. D'autres généralisations de cette formule sont donnéesThe exponential dual map is a way to encode Stokes data of a connection on a trivial vector bundle on the Riemann sphere with two poles: one double pole at 0 and one simple pole at infinity.We give here a formula for the exponential dual map expressed as a non commutative serie. Others generalizations of this formula are given
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Sulima, Mariusz. "Dyskretne przekształcenie Hilberta z wykorzystniem formatów różnicowych." Rozprawa doktorska, [Nakł.aut.], 2013. http://dlibra.utp.edu.pl/Content/605.
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W pracy zostały opisane efektywne metody polepszania dokładności i szybkości działania dyskretnego przekształcenia Hilberta (DHT). W szczególności zostały opracowane i zaprezentowane nowe: różnicowy algorytm DHT, równoległe algorytmy DHT oraz struktury procesorów specjalizowanych do ich realizacji dla sygnałów wejściowych z modulacją impulsowo-kodową i delta-modulacją, formuła charakterystyki impulsowej do DHT, zrównoleglone i skrócone charakterystyki impulsowe do DHT, kształt formuły przekształcenia Hilberta z wykorzystaniem symbolu Kroneckera
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Ahmed, I. "Developments in Hilbert transform procedures with applications to linear and non-linear structures." Thesis, University of Manchester, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378031.
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Yang, Jin-Wei, and 楊晉瑋. "Hilbert Transform-based Gait analysis." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/j87xdx.
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碩士國立臺北科技大學
電機工程研究所
104
Gait is an important factor for health care and medical diagnosis. Many researches have been focused on this topic, which tried to exploit signals of gaits for many purposes. In neurosurgery, gaits can be regarded as the coordinated action of nerves and muscles. With increase of age, between the strength of muscle and speed of transmission of nerves would be reduced. Additionally, gait could also be an indicator as a nervous system injury or degree of degeneration. Hence, it is critical to build an objective and quantifying method of gait analysis. Traditional gait analysis methods were often confined in the laboratory environment to record the actions of human gait by the sophisticated instruments. These methods are difficult to reflect actions in daily life. This thesis would like to provide a solution by investigating the smartphone-based gait analysis methods. The proposed method exploits signals from the tri-axial accelerometer embedded inside a smartphone as the sensor. The analysis first recognized seven stages of each gait cycle from signals and then applied Hilbert Transform for frequency-time domain signal analysis. Four major methods to decompose the original gait signals would be investigated in the thesis, which included Empirical Mode Decomposition (EMD), Multivariate Empirical Mode Decomposition (MEMD), Independent components analysis (ICA), Principal components analysis (PCA). Hilbert Transform was applied later to conduct the frequency-time domain analysis. A few statistical indicators were used for quantitative gait analysis. There are two major contributions of this thesis. First one is to explore the limitation of smartphone-based gait analysis. Second one aimed to provide important gait information which is difficult to be sensed by human being including medical doctors and a second opinion for medical diagnosis. According to the experimental studies, the proposed method could reveal important gait information even with very low-level smartphone. As a result, the proposed method could also be a long term recovery indicator for doctors and patients.
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Ushah, Abdurrazag M. Ali. "Application of Hilbert transform in geophysics." 1986. http://hdl.handle.net/1993/15491.
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Zeng, Zhi-Hao, and 曾志豪. "Rail Structure Analysis by Hilbert Huang Transform." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/10067070734755654714.
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碩士中原大學
土木工程研究所
94
The transportation system of the track characteristic is convenient, swift and on time. Today it has already become a part of indispensable in people’s life. The high speed train going emphasizes the importance of the structure system maintenance. The purposes of measuring the structure system of the rail are the train security guarantee, comfortableness in the course of going, disaster prevention and calamities avoidance. Accordingly, the new method which is vibration mode analysis - HHT (Hilbert Huang Transform) is proposed. This method uses the Hi-Tech vibration detecting instrument and does nondestructive inspection test. The main purpose of this research is to expect the preliminary discussion on the frequency of rail every direction before analyzing vibration by the test of the laboratory simulation and in-situ dynamic train test with the HHT vibration mode analysis and traditional Fast Fourier Transform analysis applied in this study. With the range of frequency, next step is to focus on in-situ test plan which is trying to find out the position and distance of accelerometer installation to reach effective measures by the sub ballast arrangement irregularity or hollow of sub ballast which causes the rail non-smoothly. If the outcome of this study can confirm the damage position with vibration signal and prove the feasibility and suitability of the track vibration analysis will be discussed. According to the result of study proves that the rail in the vertical direction and horizontal direction have the same frequency range definition with the references, and the main frequency range is influence on inside stress of axial direction probably 1200~1600 Hz, and by in-situ dynamic train test learn accelerometer at rail effective on quantity examine laying ranging interval between 8 m, so it is not good for the economic benefits, setting up the accelerometer on the top of the locomotive can measures effectively. As the result of study it proves the relatively analysis of the traditional Fast Fourier Transform, Average natural frequency that the frequency received has nothing to do with time, It can not find the damage position with vibration signal effectively,However, Instantaneous frequency and energy scale could be obtained as the variation of time by HHT, by this way you can calculate the damaging position in the rail structure. Therefore HHT vibration mode analysis method can get the better analysis.
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Huang, Xiu-Man, and 黃琇蔓. "Hyperspectral Image Analysis Using Hilbert-Huang Transform." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/70457907241254199875.
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碩士國立臺灣大學
土木工程學研究所
99
Hyperspectral images, which contain rich and fine spectral information, can be used to identify surface objects and improve land use/cover classification accuracy. However, traditional statistics-based classifiers cannot be directly used on such images with limited training samples. This problem is referred as “curse of dimensionality”. The commonly used method to solve this problem is dimensionality reduction, and this can be done by feature extraction for hyperspectral images. In this study, the Hilbert-Huang transform (HHT) will be applied to hyperspectral image analysis. HHT, consisting of empirical mode decomposition (EMD) and Hilbert spectral analysis (HSA), is a relatively new adaptive time-frequency analysis tool and has been used extensively in nonlinear and nonstationary data analysis. In this study, the EMD is implemented on spectral curve for absorption band analysis firstly. The experiment results show that absorption features can be detected on IMF components effectively. The other objective of this study is to apply HHT on the hyperspectral data for physically spectral analysis. The spectral features are then extracted based on the results of physically spectral analysis, so that we can get a small number of salient features, reduce the dimensionality of hyperspectral images and keep the accuracy of classification results. Finally, two AVIRIS data sets are used to test the performance of the proposed HHT-based methods. According to the experiment results, the HHT-based methods are effective for dimensionality reduction and classification.
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Wang, Yao-Sheng, and 王耀陞. "EEG Signal Analysis Using the Hilbert-Huang Transform." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/5ndy95.
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碩士淡江大學
航空太空工程學系碩士班
104
This thesis investigates the interpretation of information from brain wave, especially the way to distinguish the directions. Brain wave is so weak that many noises will be included in the received signal by an Electroencephalogram (EEG). In this research a simple EEG is used, and the Hilbert-Huang Transformation (HHT) is employed to perform empirical mode decomposition (EMD). Once the signal is decomposed, brain wave signal can be identified. Hypothesis testing in statistics is also introduced to characterize the signal. The results of this thesis is potentially applicable to the control of UAVs using EEG in the future.
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Tzu-TingChien and 簡子婷. "Analyzing Nonlinear Dynamics by the Hilbert-Huang Transform." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/34466988249681016380.
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碩士國立成功大學
光電科學與工程學系
102
In this thesis, we study the nonlinear dynamics by the Hilbert-Huang Transform (HHT).The main researches including the Lorenz attractor and the laser system with pump modulation. Analyzing the Lorenz system by HHT, the result reveals a regular ratio distribution for the fundamental frequency of 1/2, 1/4, and so on. Using HHT to investigate the pump modulated laser output; the ratio relationship of frequency is 1/5, 1/10, 1/20, etc. It shows that the difference of ratio will appear in separate system. Furthermore, HHT can become a tool to distinguish the threshold of chaotic signal due to the trend of frequency in each intrinsic mode function is similar with the Lyapunov exponent analysis.
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Yang, Kai-Hsiang, and 楊凱翔. "Hilbert-Huang Transform based ICA for ECG Denoising." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/93426925857298956925.
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碩士元智大學
資訊管理學系
97
Common techniques for ECG noise removal include wavelet transform, principal component analysis, independent component analysis (ICA) and Hilbert-Huang transform (HHT). This study proposes a two-stage ICA-based algorithm that integrates HHT with ICA to improve the performance of noise removal in ECG signals. Our performance results show that this two-stage algorithm outperforms pure ICA-based methods.
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Huang, Shiuan-Fen, and 黃玄份. "Using Hilbert-Huang transform for tourism demand forecasting." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/73410919022936868084.
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碩士國立宜蘭大學
經營管理研究所碩士班
98
The characteristics of tourism demand are non-stationary and non-linear, which render the tourism demand forecasting attracts much attention from academic researchers and business practitioners. In this paper, we propose to conduct tourism demand forecasting by combining the approaches of both Hilbert-Huang transform (HHT) and back-propagation neural network (BPN), support vector regression (SVR). The propose method can be summarized as two steps: the original series are decomposed by empirical mode decomposition (EMD), and into a finite set of intrinsic mode functions (IMFs) and a residue, which have simpler frequency components and higher correlation. Then tendencies of these IMFs and the residue are forecasted by BPN, SVR respectively. For verification and testing, we also used the pure BPN, SVR model , the ARIMA model and two series analysis model (wavelet analysis, independent component analysis) to five tourism demand series, the total tourists, Japan, Hong Kong and Macao, American and Canada tourist arrivals to Taiwan. The experimental results show that the proposed model outperforms in forecasting accuracy the pure BPN, SVR model, the ARIMA model, the wavelet analysis model, and the independent component analysis model.
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Chou, Chunhui, and 周建輝. "On direction of arrival using Hilbert-Huang Transform." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/81669446332086548334.
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碩士國立高雄海洋科技大學
海洋工程科技研究所
99
More of signal processing mathematical models were used with Fourier Transform (FT) method before. The signal analysis has to achieve a condition of linear signal for FT. In the nature, signal of nonlinear and non-steady-state as ocean, biological and geological explorations, it’s almost unable to analyze. Therefore, we use Hilbert-Huang transform (HHT) method to instead. The HHT used Intrinsic Mode Functions (IMF) and Empirical Mode Decomposition (EMD) to analyze signals, then the residual’s instantaneous frequency was found in HT. In order to make sure the component has enough physical meaning, it must avoid physical meaning of amplitude to be damaged in overmuch shift. The frequency also needs enough physical meaning and the stopped criterion, then checks integrity and orthogonal in final. The orthogonal is entirety a physical meaning, but two components in orthogonal and the data length affect the amount of leakage in locality. If two different functions are disjoint in limited data length, the amount of leakage will be increased. For nonlinear signal in the ocean, we uses HT to analyze instantaneous frequency which finds signal frequency, then assesses signal position and distance with Direction-Of-Arrival (DOA).
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Liu, Shih-Wen, and 劉世文. "Hilbert-Huang Transform Theory Applied in Electricity Loading Forecast." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/ky3mx6.
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碩士國立東華大學
電機工程學系
105
Electricity generation is a fundamental element for national development. In order to avoid any wastage of resources and energy shortage, an accurate loading forecast can provide the system with the correct schedule and planning. In this study, the essential method of Hilbert Huang Transform (HHT) is used to analyze the electric load data by empirical mode decomposition (EMD). The best prediction level can be found out through experimental observations at the intrinsic mode functions of the electric load with the variance of temperature. This study comes out an effective way to manage fluctuation time and trend of electric load. The empirical implication of this study is to correct the existing drawbacks of inspection schedule by the equipment maintenance cycle and loading forecast.
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Tseng, Hsien-Yi, and 曾獻毅. "Fault Diagnosis for Vibration Signal Using Hilbert-Huang Transform." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/44961801734565494756.
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碩士中原大學
機械工程研究所
97
The paper applies Hilbert-Huang Transform (HHT) in the vibration signals by the empirical mode decomposition (EMD), and the data can be decomposed into several intrinsic mode functions (IMFs). With the Hilbert transform (HT), the presentation of the instantaneous frequencies and amplitude that is an time-frequency-energy distribution. The energy features is excited from each intrinsic mode function and entered the back-propagation neural network to proof the intelligence fault diagnosis.
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Wang, Kuo-Ching, and 王國瑾. "Using Hilbert-Huang Transform For Credit Card Fraud Forecasting." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/20247408431612379212.
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碩士東吳大學
企業管理學系
99
Abstract Financial time series are inherently nonlinear and non-stationary, it is therefore difficult using statistical models to forecast. ANN (Artificial Neural Networks) does not require strict theoretical assumptions, so it has been applied in a wide range areas for time series forecasting. On ANN learning algorithms, the ELM (Extreme Learning Machine) overcomes the drawback of traditional Back-propagation. Inaddition,HHT (Hilbert-Huang Transform) can effectively analyze data on both nonlinear and non-stationary status. This study takes the credit card fraud amount as research subjects during the period of 2005 to 2010. We propose a hybrid forecasting model based on HHT and ELM. Firstly, by using HHT to decompose credit card fraud amount into several IMF(Intrinsic Mode Functions) and each IMF component is modeled by individual ELM respectively. The result shows that HHT can effectively improve ELM models prediction accuracy. Two models in combination would be more accurate than a single model. Keywords: Credit Card Fraud, Hilbert-Huang Transform, Extreme Learning Machine.
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Luo, Zhen gang, and 羅振剛. "Application of Hilbert-Hung transform on structural damage detection." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/45483243722524417035.
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Wang, Liang-Yuan, and 王亮元. "Application of Hilbert Transform in Time-Variant System Identification." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/50166582394824549827.
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Lu, Tz-ling, and 盧姿綾. "Application of Hilbert-Huang Transform in Sales Prediction Model." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/96804229869827453446.
Full textAbstract:
碩士東吳大學
企業管理學系
98
Sales prediction is an important issue for most enterprise in every industry. However, in the work of sales forecasting, the data of sales are usually affected by government’s policy, business cycle … etc. which make sales data include noises and instabilities. The noise of data will make time series model over fitting or under fitting and the instability will make it hard to construct a predicting model. For overcome the problem as above. This study uses the approaches of Hilbert-Huang transform (HHT), back-propagation neural network (BPN) and support vector regression (SVR). First, we use “Empirical Mode Decomposition” method of HHT to transform non-stationary and non-linear times series information into several “Intrinsic Mode Functions (IMFs)”. Second, we import IMFS by using BPN and SVR method to construct predicting model in order to reduce noise and instability. Finally, we use the sales data of six industries in Taiwan to test and verify the effectiveness of our method by compare with the data which are not transformed by HHT. Additionally, we also compare our method with Auto regressive Integrated Moving Average Models (ARIMA), Wavelet analysis and Independent Component Analysis. The results shows that our method is better than other model on predict errors.
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Lin, Yi-Chen, and 林沂臻. "A Hilbert-Huang Transform approach for predicting vegetable prices." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/8js7w6.
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碩士中山醫學大學
醫學資訊學系碩士班
105
Purpose: The research discussed the problem of vegetable price fluctuation, use Hilbert-Huang Transform algorithm to predict the future price of cabbage and radish. Method: The research picks the latest 3 years cabbage and radish price from Kaohsiung government retail sale marketplace, 2015 and 2016 price as base; 2017 price as test data. Using Hilbert-Huang Transform algorithm to predict the future price of cabbage and radish are going up or going down. Result：It can provide some useful trends in future for vegetables price prediction using the Hilbert-Huang Transform algorithm. Conclusion：The study is vegetables price prediction, pick cabbage and radish as the object of the research and the price from Kaohsiung government retail sale marketplace to do the research, Using Hilbert-Huang Transform algorithm to do the analysis, The forcast price of the radish is better than cabbage, so obviously the price of the leafy vegetables are more easily affected by temporal factor, so suggest the related policy involve earlier to reduce leafy vegetables price abnormal fluctuation.
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Yu, Sheng-Chih, and 游聲智. "Eagle Sound Classification Based on Hilbert Huang Transform Method." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/vhgpry.
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碩士國立臺灣海洋大學
電機工程學系
107
There are a variety of eagle’s species which can be recognized through feature analysis of their sound recordings. In this thesis, the two species of black hawk-eagle and black kite are chosen with their sounds to be analyzed to find the difference of sound features for recognition and classification. Research methods include the Hilbert-Huang transform and K-means clustering. To avoid erroneous decisions, the spectral subtraction method is initially used to eliminate background noise embedded in the sound recordings. Next, the Hilbert-Huang transform is utilized with the empirical mode decomposition replaced by the ensemble empirical mode decomposition (EEMD) in order to overcome the mode mixing problem. Through EEMD, the first two intrinsic mode functions are chosen to obtain their corresponding instantaneous frequencies. Their standard deviations and means are calculated as features used in the k-means clustering method for classification. To verify the feasibility of the research method, ten sound recordings from each species are downloaded and the experimental results show that the correct classification rate is 100%.
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Huang, Yu-Jen, and 黃佑任. "Using Hilbert Huang Transform Method for Bird Sound Recognition." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/vmydyh.
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碩士國立臺灣海洋大學
電機工程學系
107
There are various species of birds and how to recognize them through feature analysis of sounds is the main research objective of this thesis. Hilbert Huang Transform, the most advanced technology in signal’s time-frequency analysis, can be applied to nonlinear and nonstationary signals, such as sound signal. Therefore, the Hilbert Huang Transform is adopted to explore an effective way for automatic identification of bird’s sounds. In the Hilbert-Huang transform, the empirical mode decomposition is replaced by the ensemble empirical mode decomposition (EEMD) in order to overcome the mode mixing problem. The intrinsic mode functions (IMFs) produced from EEMD decomposition represent signals ranging from high frequency to low frequency. Through the Hilbert spectral analysis, the Hilbert amplitude spectra obtained from all IMFs as well as the first three IMFs are quite similar. Thus in order to achieve fast identification purpose, only the first three IMFs are retained for subsequent data comparison. Next, the three features of root-mean-square (RMS), peak value, and peak factor are extracted from the autocorrelation sequences of these three IMFs, and then used to calculate the Pearson product-moment correlation coefficient (PPMCC) for the basis of recognition. Experimental results show that successful recognition can be achieved from the database that contains sound recordings originated from eight different species of birds。
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Chen, Mei-Feng, and 陳美芬. "Study of Total Hip Prosthesis Loosening by Hilbert Huang Transform and Fast Fourier Transform." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/5czgwq.
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碩士中原大學
醫學工程研究所
91
Total hip replacement arthroplasty (THR) is a common operation on Orthopedics. The most serious common complication of THR is loosening of the prosthetic stem and cup. This study used Hilbert Huang Transform (HHT) and Fast Fourier Transform (FFT) to analyse the vibrational signals of different posture and position, then compared the results by using three parameters: Accuracy, Sensitivity and Specificity. The study used non-invasive sonic vibration measurement system to measure the vibrational signal of different posture and position, (a) lie on the back-Anterior Superior iliac Spine (ASIS), (b) lie on the side-ASIS, (c)lie on the side-Greater trochanter, and analysed the vibrational signals by HHT and FFT. According to the signal amplitude of harmonic, the system would indicate that the prosthesis was loosening or secure, and then compared with clinical diagnosis based on the patient’s radiograph. The signal resolution abilities of HHT and FFT were evaluated by three parameters. Besides, the inferences of postures and positions on vibrational signal had been completed discussion in this study. The results showed that the HHT had better accuracy and sensitivity than FFT, and it meant that the HHT could raise the ability in diagnosing loosening of THA. Furthermore, the measurement of postures and positions would affect the accuracy in different kinds of loosening . Using vibrational signal to detect loosening of THA was worth developing, and the HHT was a proper method in analysing loosening signal of THA.
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Lin, Da-Chi, and 林達祺. "The Application of Hilbert Transform and Wavelet Transform on the Ground Penetrating Radar Signal." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/49825659348466735758.
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碩士國立成功大學
土木工程學系碩博士班
95
In this study, ground penetrating radar (GPR) is used to scan the pipes buried in the sand box that is filled with Ottawa sand. The model tests can be divided into six cases: (1) single layer of PVC pipe (2) single layer of metal pipe (3) double layers of PVC pipes in the vertical array (4) double layers of metal pipes in the vertical array (5) double layers in the vertical array with one metal pipe below the PVC pipe (6) double layers in the vertical array with one PVC pipe below the metal pipe. After the tests, Hilbert transform and Wavelet transform are used to GPR signal analyzing. Then, Hilbert transform amplitude, phase angle and Wavelet transform figures are drawn. The results show that the position, depth and diameter of overlap pipes can be identified easily with using the Hilbert transform and Wavelet transform for signal processing. Through a series of GPR experimentations and the signal analyzing with using Hilbert and Wavelet transform, we hope that the correct ratio of the GPR test result of judging the pipes underground can be increased in nondestructive testing (NDT) and let GPR become an economical and efficient examination method in the future.
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Huang, Kuo-Hao, and 黃國豪. "Hilbert-Huang Transform (HHT) Based technique for Identifying Looseness of Rotating Machinery through Marginal Hilbert Spectrum Analysis." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/53832042836410293081.
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碩士國立中央大學
光機電工程研究所
97
The purpose of the research in this paper is to investigate the feasibility of utilizing the marginal Hilbert spectra of vibration signals to identify the looseness faults at different components of rotating machinery. The faulty signals of rotating machinery are generally nonlinear and non-stationary. The traditional Fourier-based spectral analysis can not precisely describe the nonlinear or non-stationary vibration behavior. Therefore, it motivates this research to use an alternative method to analyze the complicated vibration signals. Under such conditions, Huang et al. (1998) propose a new method, termed as Hilbert-Huang Transform (HHT), to analyze the nonlinear or non-stationary data. Through the Ensemble Empirical Mode Decomposition (EEMD) method, the original data can be decomposed into several Intrinsic Mode Function (IMF) components. The information-contained IMFs are extracted through the significance test and removing the low frequency components. The marginal Hilbert spectra consist of the information-contained IMFs and represent the characteristics of the machine operating condition. The fault indicator index that is combined by Mahalanobis distance and cosine index is defined to measure the spectral similarities among different looseness types in the operating machinery. The effectiveness of the proposed method is evaluated by analyzing the marginal Hilbert spectra of vibration signals in the different types of looseness faults. A test bed of rotor-bearing system (PBS-5000) is performed to illustrate the looseness faults at different mechanical components. The results show that the proposed diagnose method is capable of enhancing the distinction quantities of different marginal Hilbert spectra distributions, and thus identify the type of looseness fault at machinery.
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唐周宜. "Integrated analysis of wavelet and Hilbert transform in GPR survey." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/37248068940739291368.
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