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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Security and robustness of a modified parameter modulation communication scheme

Liang, Xiyin. January 2009 (has links)
Thesis (Ph.D.(Electronic engineering))--University of Pretoria, 2008. / Summary in English. Includes bibliographical references.
222

Box-counting dimension and beyond /

Archer, Kassie. January 2009 (has links)
Thesis (Honors)--College of William and Mary, 2009. / Includes bibliographical references (leaves 56-57). Also available via the World Wide Web.
223

A generalized approach to the control of the evolution of a molecular system /

Tang, Hui. January 1997 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Physics, December 1997. / Includes bibliographical references. Also available on the Internet.
224

Chaotic optical communications using delayed feedback systems

Locquet, Alexandre Daniel. January 2005 (has links)
Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2006. / Bertrand Boussert, Committee Member ; Douglas B. Williams, Committee Member ; William T. Rhodes, Committee Member ; Yves Berthelot, Committee Member ; David S. Citrin, Committee Chair.
225

A study of the nonlinear dynamics nature of ECG signals using Chaos theory

Tang, Man, January 2005 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.
226

Chaos theory and Robert Wilson a critical analysis of Wilson's visual arts and theatrical performances /

Manzoor, Shahida. January 2003 (has links)
Thesis (Ph.D.)--Ohio University, June, 2003. / Title from PDF t.p. Includes bibliographical references (leaves 205-239)
227

Tilt phase transitions in disordered systems /

Chen, Leiming. January 2006 (has links)
Thesis (Ph. D.)--University of Oregon, 2006. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 126-128). Also available for download via the World Wide Web; free to University of Oregon users.
228

Μη γραμμική ανάλυση αιτιακών αλληλεπιδράσεων σε ηλεκτροεγκεφαλογράφημα

Κορδά, Αλεξάνδρα 26 September 2011 (has links)
Σκοπός της παρούσας διπλωματικής εργασίας ήταν η μελέτη ηλεκτροεγκεφαλογραφικών σημάτων επιληψίας με χρήση συνδεδεμένων χαοτικών συστημάτων. Στο πλαίσιο της εργασίας παρουσιάζονται αρχικά μέθοδοι συμφωνίας και οι διάφορες μορφές της συνάρτησης μεταφοράς πληροφορίας. Οι τεχνικές που έχουν χρησιμοποιηθεί κυρίως μέχρι σήμερα είναι γραμμικές ωστόσο έχει φανεί σε αρκετές περιπτώσεις ότι η γραμμικότητα δεν επαρκή για την εξήγηση των σημάτων ΗΕΓ και της σύζευξης μεταξύ τους. Για τον λόγο αυτόν αναπτύσσεται η μη γραμμική μέθοδος υπολογισμού της συνάρτησης μερικής κατευθυνόμενης συμφωνίας η οποία μελετά τα καταγεγραμμένα σήματα στον χώρο φάσης-κατάστασης. Βάση αυτής διερευνάται η μη γραμμική συνδεσιμότητα περιοχών του εγκεφάλου. Η εργασία αποτελείται από πέντε μέρη. Το πρώτο μέρος περιλαμβάνει τη παρουσίαση της φυσιολογίας του ανθρώπινου εγκεφάλου. Στο δεύτεροο μέρος παρουσιάζεται η ασθένεια της επιληψίας καθώς και οι διάφοροι τύποι της. Στο τρίτο μέρος παρουσιάζεται η μέθοδος της μη γραμμικής ανάλυσης χρονοσειρών μέσω της μερικής κατευθυνόμενης συμφωνίας που περιλαμβάνει την ανακατασκευή των σημάτων στον φασικό χώρο. Ακολουθεί ο υπολογισμός των κατάλληλων παραμέτρων για την σωστή ανακατασκευή του φασικού χώρου των σημάτων. Τέλος, στο πέμπτο κεφάλαιο παρουσιάζονται αποτελέσματα από εφαρμογή της μεθόδου σε προσομοιωμένα δεδομένα,καθώς και σε πραγματικά δεδομένα από ασθενή με επιληψία, τα οποία έχουν ληφθεί από το νοσοκομείο Ευαγγελισμός. / This diploma thesis aim at studying Electroencephalografic (EEG) Signal Recordings by adopting methodologies able to analyse and observe coupling of chaotic systems. Although linear methods seems to be inadequate for the analysis of EEG signals, the most commonly used methodologies today are linear. In this thesis, a non-linear partial directed coherence method is adopted to compute the transfer function of EEG signals in the phase-state space and is used to estimate the non-linear connectivity among brain areas. This thesis consists of five chapters. In the first and second chapter, an introduction to the brain's physiology and epilepsy pathophysiology is presented. In the third chapter, a methodology for the non-linear analysis of time series is presented based on the PDC method, which reconstructs attractors in the phase-state. In the fourth chapter, the parameters for the phase-state reconstruction of the attractors are properly selected. In the fifth chapter, the proposed method is applied on simulated and real epilepsy EEG data and the obtained results are presented and discussed.
229

Chaotic Environment and Child Behavior Problems: A Comparative Study of High-Conflict Never Married and Divorcing Parents

January 2011 (has links)
abstract: Never married parents (NMPs) are a burgeoning population within the Family Court system. However, there is no empirical research on these parents' separation process, though the neighboring literature purports that NMPs are more at risk for negative child wellbeing outcomes than their divorcing counterparts. This study investigated child behavior problems in high conflict litigating never married families by assessing four salient issues collectively termed chaotic environment: economic strain, lack of social support for the parents, parental repartnering, and family relocation, which included parent changing residence and child changing schools. They were then compared to divorcing parents. It was hypothesized that NMPs would experience higher levels of chaotic environment, and subsequent increases in child behavior problems than divorcing parents, but that the relationship for NMPs and divorcing parents would be the same with each of the chaotic environment variables. This study found the contrary. NMPs only had significantly higher mean scores on lack of social support for fathers and marital status did not predict child behavior problems. Both economic strain and child changing schools predicted child behavior problems for both mothers and fathers. Two interaction effects with mothers were found, indicating that the more a never married mothers repartnered and/or changed her residence, the more behavior problems her child had, while divorcing mothers experiencing the converse effect. / Dissertation/Thesis / Ph.D. Counseling Psychology 2011
230

Estudo de difusão caótica em um modelo de poço de potencial dependente do tempo / Study of chaotic diffusion in a time-dependent potential well model

Graciano, Flávio Heleno [UNESP] 08 August 2018 (has links)
Submitted by Flavio Heleno Graciano (flavio.graciano@ifsuldeminas.edu.br) on 2018-09-29T12:38:30Z No. of bitstreams: 1 Dissertação corrigida e finalizada _ Flavio H_ UNESP_2018.pdf: 1246697 bytes, checksum: b5d8b99a207e2d0aed931aa653ce4158 (MD5) / Rejected by Adriana Aparecida Puerta null (dripuerta@rc.unesp.br), reason: Prezado Flávio, O documento enviado para a coleção Campus Unesp Rio Claro foi recusado pelo(s) seguinte(s) motivo(s): - Falta a capa, elemento obrigatório. - Falta a ficha catalográfica, que deve ser gerada no site (https://www.biblioteca.unesp.br/ficha/) e inserida após a folha de rosto no arquivo pdf e no verso da folha de rosto na versão impressa. - Folha de aprovação: dados incompletos. Falta: data de aprovação, nome com titulação e instituição as quais pertencem os componentes da banca, constar a informação "APROVADO" (deve ser solicitada à Seção de Pós-Graduação e deve ser inserida após a ficha catalográfica). - No Resumo e no Abstract faltam as palavras chaves em português e em inglês. - Lista de Figuras deve vir antes do Sumário. Agradecemos a compreensão e aguardamos o envio do novo arquivo. Atenciosamente, Biblioteca Campus Rio Claro Repositório Institucional UNESP https://repositorio.unesp.br on 2018-10-01T19:39:26Z (GMT) / Submitted by Flavio Heleno Graciano (flavio.graciano@ifsuldeminas.edu.br) on 2018-10-02T11:28:23Z No. of bitstreams: 1 Dissertação Flavio Heleno final.pdf: 1713409 bytes, checksum: 7c4502d3e3e10e12f47338317dfa197c (MD5) / Approved for entry into archive by Adriana Aparecida Puerta null (dripuerta@rc.unesp.br) on 2018-10-02T19:16:24Z (GMT) No. of bitstreams: 1 graciano_fh_me_rcla.pdf: 1713409 bytes, checksum: 7c4502d3e3e10e12f47338317dfa197c (MD5) / Made available in DSpace on 2018-10-02T19:16:24Z (GMT). No. of bitstreams: 1 graciano_fh_me_rcla.pdf: 1713409 bytes, checksum: 7c4502d3e3e10e12f47338317dfa197c (MD5) Previous issue date: 2018-08-08 / Neste trabalho consideramos o modelo do poço de potencial dependente do tempo e construimos de forma detalhada o mapeamento discreto bidimensional nas variáveis energia e fase que descreve a dinâmica do sistema. Mostramos que o espaço de fases é do tipo misto, contendo mares de caos, curvas invariantes e ilhas de estabilidade. Encontramos a matriz Jacobiana para o mapeamento assim como seu determinante, confirmando a propriedade de preservação de área. Estudamos a evolução no tempo da energia quadrática média e discutimos leis de escala para o comportamento dessa evolução. Por fim demos início à resolução da equação da difusão a fim de encontrarmos uma equação analitíca para energia quadrática média. / In this work we consider the model of the time-dependent potential well and we construct in detail the two-dimensional discrete mapping in the energy and phase variables that describes the dynamics of the system. We show that the phase space is of the mixed type, containing chaotic seas, invariant curves and stability islands. We obtain the Jacobian matrix for the mapping as well as its determinant, confirming the area preservation property. We study the evolution in time of the average squared energy and discuss scaling laws for the behavior of this evolution. Finally we started the resolution of the diffusion equation in order to find an analytical equation for mean quadratic energy.

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