Dissertations / Theses on the topic 'Modulation'
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Cevik, Gozde. "Feature Based Modulation Recognition For Intrapulse Modulations." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607676/index.pdf.
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In this thesis study, a new method for automatic recognition of intrapulse modulations has been proposed. This new method deals the problem of modulation recognition with a feature-based approach.
The features used to recognize the modulation type are Instantaneous Frequency, Instantaneous Bandwidth, Amplitude Modulation Depth, Box Dimension and Information Dimension. Instantaneous Bandwidth and Instantaneous Frequency features are extracted via Autoregressive Spectrum Modeling. Amplitude Modulation Depth is used to express the depth of amplitude change on the signal. The other features, Box Dimension and Information Dimension, are extracted using Fractal Theory in order to classify the modulations on signals depending on their shapes. A modulation database is used in association with Fractal Theory to decide on the modulation type of the analyzed signal, by means of a distance metric among fractal dimensions. Utilizing these features in a hierarchical flow, the new modulation recognition method is achieved.
The proposed method has been tested for various intrapulse modulation types. It has been observed that the method has acceptably good performance even for low SNR cases and for signals with small PW.
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LING, LAI-CHANG. "PHOTOEMITTER MEMBRANE SPATIAL LIGHT MODULATOR (SIGNAL PROCESSING, PHASE MODULATION)." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183921.
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Advantages of optics over electronics in signal processing derive from the fact that many operations, such as addition, multiplication, correlation, and filtering, can be performed in parallel on two-dimensional data samples. However, this advantage is attainable only if information can be input/output or processed at sufficient speed and space bandwidth. Although acousto-optic devices have been used to provide impressive throughput, they are inherently one-dimensional and do not possess any information-storage capability beyond the acoustic transit time (≤50 μs). Hence, a high-resolution high-speed two-dimensional transducer (or spatial light modulator, SLM) with real-time update capability is required. Unfortunately, none of the existing SLMs perform well enough to fully utilize the inherent speed and parallelism of the optics. This dissertation addresses the development of an SLM that has the potential to meet most of the performance requirements of advanced optical information-processing applications--the photoemitter membrane light modulator (PEMLM). At the heart of the PEMLM is a microchannel plate (MCP) with a flexible membrane covering each pore. In operation, the write image incident on a photocathode, which is placed on the input side of the MCP, creates an electron image. This electron image is then amplified by the MCP and deposited onto the membrane array. The membrane elements, which are electrically and mechanically isolated from each other, are deflected by the induced electrostatic forces. These deflections represent the stored information. Readout of stored information is accomplished by sensing the phase changes induced in an optical-readout beam reflected from the deformed membrane array. A sandwich-type electrostatic grid structure positioned between the MCP and membrane greatly enhances the versatility of the PEMLM by facilitating the use of secondary emission for active electron removal and various intrinsic operations. The theoretical analysis and experimental characterizations performed on prototype devices indicates that PEMLM is capable of higher throughput than most other SLMs, with expected resolutions approaching 50 lp/mm over 10⁷ resolution elements and framing rates greater than 1 KHz. MCP gains provides quantum-limited sensitivity. The PEMLM also promises information-storage times of minutes to hours, greater than 2π phase modulation, good image quality, and an option for serial addressing. In addition, the PEMLM can intrinsically perform operations such as intensity thresholding, contrast modification, edge enhancement, binary logic, synchronous detection, and image addition/subtraction.
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Chafii, Marwa. "Etude d'une nouvelle forme d'onde multiporteuses à PAPR réduit." Thesis, CentraleSupélec, 2016. http://www.theses.fr/2016SUPL0008/document.
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L’OFDM est une technique de modulation multiporteuses largement utilisée dans des applications de communications filaires et sans-fils comme le DVB-T/T2, le Wifi, et la 4G, grâce à sa robustesse contre les canaux sélectifs en fréquence en comparaison avec la modulation monoporteuse. Cependant, le signal OFDM souffre de grandes variations d’amplitude. Les fluctuations de l’enveloppe du signal OFDM génèrent des distorsions non-linéaires quand on introduit le signal dans un équipement non-linéaire comme l’amplificateur de puissance. Réduire les variations du signal améliore le rendement de l’amplificateur, réduit la consommation énergétique et diminue les émissions de CO2 des transmissions numériques.Le PAPR (rapport de la puissance crête sur la puissance moyenne) est une variable aléatoire qui a été introduite pour mesurer les variations du signal. Il existe plusieurs systèmes multiporteuses basés sur différentes bases de modulation et filtres de mise en forme. Nous prouvons d’abord dans ces travaux que le PAPR dépend de cette structure de modulation. Ensuite, nous étudions le comportement du PAPR vis-à-vis des formes d’ondes utilisées dans la modulation. Le problème de réduction du PAPR est ainsi formulé en un problème d’optimisation. Par ailleurs, une condition nécessaire pour construire des formes d’ondes avec un meilleur PAPR que l’OFDM est développée. Cette condition est notamment satisfaite par des bases en ondelettes. Enfin, une nouvelle forme d’onde en paquets d’ondelettes adaptative est proposée, permettant des gains significatifs en PAPR, tout en maintenant les avantages des modulations multiporteusesOFDM is a multicarrier modulation system widely used in wireline and wireless applications such as DVB-T/T2, Wifi, and 4G, due to its resilience against frequency selective channels compared with the single carrier modulation systems. However, the OFDM signal suffers from large amplitude variations. The fluctuations of the OFDM envelope generate non-linear distortions when we introduce the signal into a non-linear device like the power amplifier. Reducing the variations of the signal improves the power amplifier efficiency, reduces the energy consumption and decreases CO2 emissions.The peak-to-average power ratio (PAPR) has been introduced as a random variable that measures the power variations of the signal. There exist several multicarrier modulation systems based on different modulation basis and shaping filters. We first prove in this work that the PAPR depends on this modulation structure. Moreover, the behaviour of the PAPR regarding to the modulation waveforms is analysed and the PAPR reduction problem is formulated as an optimization problem. Furthermore, a necessary condition for designing waveforms with better PAPR than OFDM is developed. This necessary condition is particularly satisfied by wavelet basis. Finally, a new adaptive wavelet packet waveform is proposed, allowing significant gain in terms of PAPR, while keeping the advantages of multicarrier modulations
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Bhatranand, Apichai. "Electrooptic light modulator with improved response linearity using optical feedback." Diss., Texas A&M University, 2004. http://hdl.handle.net/1969.1/2750.
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The use of optical feedback for improving response linearity of electrooptic light modulators has been investigated. The modulator is configured as a straight channel waveguide flanked by electrodes in a lithium niobate (LiNbO3) substrate. Light is coupled into the waveguide in both TE and TM polarizations, and a voltage applied across electrodes causes a relative phase shift between two polarization components. An output analyzer converts the phase modulation to intensity modulation. Optical feedback of light in both polarization modes results from reflection of light at the polished edges of the substrate. Channel waveguides supporting a single guided mode for TE and TM polarizations were fabricated in x-cut LiNbO3 substrates using titanium-indiffusion technique. The waveguides and modulators were characterized at a wavelength of 1.55 ??m using a distributed feedback laser. The modulators were driven with a sinusoidal voltage waveform. To minimize harmonics of the modulating frequency in the intensity output, the magnitude of the optical feedback and the substrate temperature were adjusted. The feedback level was altered by applying refractive index-matching liquid to one or both ends of the waveguide at the edges of the crystal. It was found that a high degree of response linearity in the presence of feedback was achievable at certain substrate temperatures. The spurious-free dynamic range (SFDR) relative to the noise floor was measured at different feedback levels and substrate temperatures in an effort to maximize the modulator response linearity. An SFDR of 68.04 dB, limited by third-order nonlinearity, was achieved by applying index-matching fluid to the input end of the substrate. This compares with an SFDR of 64.84 dB limited by second-order nonlinearity when index-matching fluid was applied at both ends of the substrate. By changing the temperature of the same substrate to adjust the phase shifts experienced by TE and TM polarizations, the SFDR with index-matching fluid at the input end increased to 71.83 dB, limited by third-order nonlinearity. In tests at constant modulation depth, an improvement of as much as 9.6 dB in SFDR vs. the theoretical value for an interferometric modulator without feedback was achieved.
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Almgren, Björn. "Dynamic load modulation." Thesis, University of Gävle, Department of Technology and Built Environment, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-702.
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The purpose of this master thesis was to study if the drain efficiency of power amplifiers can be maintained at power back off using a technique called load modulation.
The amplifier classes studied are E, F and D-1. The target figure was to obtain a 10 to 12 dB dynamic range of amplitude with reasonable efficiency. Studies of power amplifiers have been made to understand how power is generated. Several different load modulation networks have been evaluated. Attempts to derive design equations for the modulation networks have also been done.
The thesis work was carried out with simulations in ADS 2006. As active devices commercially available bare-die transistor models have been used. The power rating of the dies are 15 W.
A dynamic range of amplitude of over 15 dB has been achieved with drain efficiency greater than 60 percent. The peak output power is in the 40 – 45 dBm range.
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Erdem, Erem. "Digital Modulation Recognition." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12611281/index.pdf.
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In this thesis work, automatic recognition algorithms for digital modulated signals are surveyed.
Feature extraction and classification algorithm stages are the main parts of a modulation recognition system. Performance of the modulation recognition system mainly depends on the prior knowledge of some of the signal parameters, selection of the key features and classification algorithm selection.
Unfortunately, most of the features require some of the signal parameters such as carrier frequency, pulse shape, time of arrival, initial phase, symbol rate, signal to noise ratio, to be known or to be extracted. Thus, in this thesis, features which do not require prior knowledge of the signal parameters, such as the number of the peaks in the envelope histogram and the locations of these peaks, the number of peaks in the frequency histogram, higher order moments of the signal are considered. Particularly, symbol rate and signal to noise ratio estimation methods are surveyed. A method based on the cyclostationarity analysis is used for symbol rate estimation and a method based on the eigenvector decomposition is used for the estimation of signal to noise ratio. Also, estimated signal to noise ratio is used to improve the performance of the classification algorithm.
Two methods are proposed for modulation recognition:
1) Decision tree based method
2) Bayesian based classification method
A method to estimate the symbol rate and carrier frequency offset of minimum-shift keying (MSK) signal is also investigated.
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Torres, Wade Patrick. "Generalized frequency modulation." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8697.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.Includes bibliographical references (p. 127-128).
In frequency modulation (FM) systems, a continuous-time information signal is modulated onto a sinusoidal carrier wave by using the information signal to modulate the frequency of the carrier wave. In this thesis, a more general type of modulation is developed, of which FM is a special case, that we refer to as rate modulation. A rate modulation system consists of a dynamical system whose rate of evolution is varied in proportion to an information signal. The rate-modulated carrier wave is a scalar function of the state variables of the modulator. The thesis is focused on three aspects of rate modulation and demodulation systems. First, explicit expressions are derived for the power density spectrum of the rate modulated carrier wave for sinusoidal modulation. Second, a systematic procedure is derived for constructing demodulators. This procedure requires that the dynamical system used in the modulator has a known exponentially convergent observer. Assuming such an observer is known, a systematic procedure for constructing demodulators is given that depends on the underlying dynamical system in a simple manner. Finally, the quasi-moment neglect closure technique is used to approximate the signal-to-noise ratio when the carrier wave is corrupted by additive white-noise.
by Wade P. Torres.
Ph.D.
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Tong, Jun. "Superposition coded modulation /." access full-text access abstract and table of contents, 2009. http://libweb.cityu.edu.hk/cgi-bin/ezdb/thesis.pl?phd-ee-b23750455f.pdf.
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Thesis (Ph.D.)--City University of Hong Kong, 2009."Submitted to Department of Electronic Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy." Includes bibliographical references (leaves [142]-152)
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Chakraborty, Arup Lal. "Calibration-free wavelength modulation spectroscopy with elimination of residual amplitude modulation." Thesis, University of Strathclyde, 2010. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=14437.
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Bouchard, Jean-Luc. "La modulation agogique : définition, typologie et analogie avec la modulation tonale." Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25071/25071.pdf.
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Muhsen, Ahmad Abdel Rahman Mohammad. "Interactions between Manipulation Induced Pain Modulation and Conditioned Pain Modulation Analgesia." Thesis, Curtin University, 2018. http://hdl.handle.net/20.500.11937/77112.
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The overall objective of this thesis was to improve our understanding of two forms of endogenous analgesia induced by conditioned pain modulation and manipulation induced pain modulation. The studies presented in this thesis have shown a significant association and a comparable increase in CPM and MIPM analgesia in response to enhanced empathetic interaction and aerobic exercise. This suggests that both forms of EA are potentially mediated by a common neuro-physiological mechanism.
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Khalili, Fatemeh. "Design and Simulation of Coded-Modulation Using Turbo Trellis Coding and Multi-Layer Modulations." Ohio University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1510064128952891.
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SCOMAZZON, PASCAL TOSSER-ROUSSEY ANDRE. "ETUDE COMPARATIVE DE MODULATIONS NUMERIQUES D'UNE SOUS-PORTEUSE EN RADIODIFFUSION A MODULATION DE FREQUENCE /." [S.l.] : [s.n.], 1992. ftp://ftp.scd.univ-metz.fr/pub/Theses/1992/Scomazzon.Pasal.SMZ926.pdf.
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Chen, Yun [Verfasser]. "Automatic Modulation Classification in Mobile OFDM Systems with Adaptive Modulation / Yun Chen." Aachen : Shaker, 2014. http://d-nb.info/1049380568/34.
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Šiška, Martin. "Impulzové modulace." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220215.
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This work deals with the analysis of pulse modulation issues, work is divided into six chapters. The first chapter of the thesis deals with pulse modulations as a whole. It explains the concept of modulation, the distinction between analog and digital modulation, and there is the basic classification of pulse modulation done. The second chapter focuses on the issue of non-quantized pulse modulation. For each modulation belonging to this group is verbally and graphically explains the principle of its activities. In the third chapter, which is similar to the second chapter, the work focuses on quantized pulse modulation. Again, each of these modulations explained its basic principle. It is also in this chapter outlines the design models in Matlab-Simulink. The fourth chapter presents calculations and tables with calculated values needed for simulations. In the fifth chapter, a comparison waveforms. It contains a discussion about the dependence of modulation on their parameters, parameters of the input signal and the sampling frequency. In the final sixth chapter deals with the early design concepts and detailed diagrams for the production of demonstration products.
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Kwan, Terry Tai-Wing. "Corridor asynchronous delta modulation." Thesis, University of Ottawa (Canada), 1989. http://hdl.handle.net/10393/5932.
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Ventevogel, Melissa Samo. "Cytokine Modulation of Thymopoiesis." NCSU, 2008. http://www.lib.ncsu.edu/theses/available/etd-03182008-100350/.
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The thymus is an organ derived from embryonic endoderm and mesoderm differentiation. It is located above the heart and is made up of two compartments, the thymic epithelial space and the perivascular space. The thymic epithelial space consists of the cortex and the medulla, which is where T cell development, maturation and induction of self tolerance occur in a process known as thymopoiesis. The thymus is susceptible to chronic and acute stressors that result in thymic involution. A consequence of thymic involution is reduced thymopoiesis, which affects the generation of a diverse T cell repertoire and establishment of central T cell tolerance. Many thymosuppressive and thymostimulatory cytokines are involved in thymopoiesis and thymic involution. Keratinocyte growth factor and IL-7 are two cytokines that function in driving early thymic progenitor proliferation and T cell development, respectively. We hypothesized that IL-7 and Keratinocyte growth factor, delivered via recombinant adenovirus, can improve thymopoiesis and T cell reconstitution in mice in an endotoxin model of acute thymic atrophy. Analysis of thymus weight, cellularity, phenotype and TCR gene rearrangement showed moderate increases in thymic function with delivery of IL-7 or Keratinocyte growth factor versus control. Taken together, these data suggested that IL-7 and Keratinocyte growth factor, delivered via recombinant adenoviruses, have thymostimulatory effects on the thymus in normal thymus or settings of acute thymic atrophy and maybe beneficial for future development as therapeutics.
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Rogers, L. Warren. "Synthetic space vector modulation." Monterey, California: Naval Postgraduate School, 2013. http://hdl.handle.net/10945/34731.
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Approved for public release; distribution is unlimitedAlternating current motors are used throughout the fleet because of their rugged construction and nearly maintenance free operation. Since the U.S. Navy is exploring and acting on the possibilities of DC distribution systems, the need exists for simple, reliable three-phase voltage source inverter (VSI) powered induction machines. Until recently, VSIs utilized a pulse width modulation (PWM) scheme controlling the frequency and amplitude of each phase. A novel and simple hardware centered VSI controller was designed, simulated, built and tested featuring a type of space vector modulation (SVM). Design criteria evaluated such as VSI frequency response, switching losses, dead-time and SVM switching sequences were considered. Specifically, modulo-6 and 12 synthetic SVM units were evaluated for future Department of Defense use.
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Arani, Faramarz Shayan. "Trellis coded modulation techniques." Thesis, University of Warwick, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387324.
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Redwood-Sawyerr, J. A. S. "Constant envelope modulation coding." Thesis, University of Essex, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356049.
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POLO, MARIA GUILLERMINA ALBARRACIN. "MODULATION TECHNIQUES IN EHF." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=27198@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
Devido às exigências da largura de banda, especialmente nas comunicações sem fios que são cada dia maiores pelo aumento do numero de usuários, é necessário estudar a banda de EHF(Extremely High Frequency). A transmissão e recepção de dados em EHF constitui uma possível solução para aliviar a escassez do espectro e satisfazer a crescente demanda de maiores velocidades tentado resolver as limitações dos sistemas atuais. As ondas de radio na banda EHF vão de 30 até 300 GHz e são chamadas ondas milimétricas, já que seus comprimentos de onda vão de 10 mm até 1 mm. Neste trabalho, a montagem de um sistema de geração e detecção de ondas de EHF a partir do batimento de dois lasers é apresentada. Técnicas de modulação e demodulação em fase, amplitude e frequência na faixa de 200-300 GHz são demonstradas.
The capacity of wireless communications has started to reach the top and the unstoppable increase of users is becoming a problem because more bandwidth is needed, which has gave rise to the study of EHF (Extremely High Frequency) band. Transmission and reception of data in EHF is shown as a solution to alleviate the scarcity of the spectrum and to meet the request of faster speeds to solve the limitation of the actual systems. The range of radio waves in EHF band go from 30 to 300 GHz, and are called millimeter waves since their wavelengths are between 10mm and 1mm. In this work is presented a system capable to generate and detect EHF waves from the beating of two lasers, and at the same time different modulation and demodulation techniques (phase, amplitude and frequency) are presented.
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Tsai, Hsin-Yu Sidney. "Absorbance modulation optical lithography." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/42253.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 91-94).
In this thesis, the concept of absorbance-modulation optical lithography (AMOL) is described, and the feasibility experimentally verified. AMOL is an implementation of nodal lithography, which is not bounded by the diffraction limit of incident lights. Experimental results showed promising capability of AMOL and matched well with simulation. Several key elements of the AMOL system are discussed: the material systems of AMOL, limitations on the material and optical systems presented, and the design and fabrication of spiral phase elements that generate ring-shaped beams required by AMOL.
by Hsin-Yu Sidney Tsai.
S.M.
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Lewis, Ray. "Autotracking Antenna Modulation Methodology." International Foundation for Telemetering, 2013. http://hdl.handle.net/10150/579581.
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ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NVThe tracking modulation index (Km) is a key performance parameter for any autotracking antenna and should especially be considered for classically difficult targets such as missiles and/or fast moving aircraft. Antenna subsystems are typically characterized by their gain to temperature ratio (G/T) to optimize receive data bit error rates (BER) for distant targets. One important parameter often overlooked for telemetry autotracking antennas is a graded value for the available tracking modulation index (Km) that is common in radar autotracking applications. Tracking modulation performance is a major contributor for minimizing the antenna pointing error during an autotrack mission. Autotracking radar antenna specifications typically include tracking modulation as a major design parameter, many receive-only autotrack antennas used for telemetry applications do not consider this important parameter for the intended tracking mission which may result in poor autotracking performance. This paper investigates the effects of tracking modulation levels on system pointing errors for various classes of feed topologies.
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Zokaei, N. "Modulation of working memory." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1393276/.
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Visual working memory, a limited temporary storage system for relevant information, is a critical contributor to many essential cognitive functions. In this thesis, I aimed to investigate some of the mechanisms underlying working memory in healthy humans and neurological patients, as well as its modulation by processes attributed to attention and the neurotransmitter dopamine. There currently is an important controversy regarding models of working memory. I investigated whether a resource model of memory (which argues for a limited resource distributed amongst to-be-remembered items) might be extended to the domain of visual motion. The results suggest that this is indeed be the case, supporting the utility of this model as a general conceptual framework for understanding working memory across a range of visual features and modes of presentation (Chapter 2). A comprehensive model of working memory should consider its relationship with attention. My findings point to an intimate yet highly specific relationship between these two processes, demonstrating that attention is essential for maintenance of integrated features within working memory (Chapters 2 and 4). Further, evidence for a causal role of early visual areas in maintenance of items in focus of attention, compared to the full content of working memory, is provided using transcranial magnetic stimulation (Chapter 3). Finally, I investigated neuromodulation of working memory processes by dopamine in patients with dopamine dysfunction (Parkinson’s disease) and using the dopamine agonist, Cabergoline, in healthy controls. The results demonstrate that dopamine can modulate working memory precision (Chapter 5 and 6). Furthermore, deficits in working memory were also observed in individuals with glucocerebrosidase mutations who have a significantly raised risk of developing Parkinson’s disease (Chapter 7). I discuss the possibility that specific deficits in working memory might provide a cognitive marker of risk for neurodegeneration and development of Parkinson’s disease.
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Skandali, Nikolina. "Serotonergic modulation of cognition." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/277921.
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Action control arises from the interaction of two anatomically distinct decision-making systems, namely goal-directed and habitual behaviour. Goal-directed behaviour is characterized by the consideration of future choices and respective outcomes whereas habitual responding is driven by stimulus-response associations. Response inhibition is essential for goal-directed behaviour and deficits are shown in impulsivity. We administered an acute clinically relevant dosage of the commonly used serotonin reuptake inhibitor escitalopram to sixty-six healthy volunteers in a double-blind, randomized, placebo-controlled design. We administered a large task battery in order to study the effect of escitalopram in several cognitive functions including response inhibition, learning and affective processing. We found dissociate effects on cognitive aspects possibly mediated by distinct cortico-striatal loops. Acute escitalopram administration had a beneficial effect on action cancellation, one aspect of inhibitory control, without any effect on action restraint or waiting impulsivity. The treatment resulted in impaired performance in a probabilistic reversal-learning task and increased sensitivity to misleading feedback thus leading to maladaptive performance. An extra-dimensional set shift impairment during an attention set shift task and a tendency towards impaired instrumental learning discrimination were also observed in the escitalopram group. Our results are discussed in the context of well-documented effects of the dopaminergic system and suggestions of opponent interaction of serotonin and dopamine.
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Guedj, Carole. "Modulation noradrénergique de l’attention." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1294/document.
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La neuromodulation apporte une extraordinaire richesse à la dynamique des réseaux de neurones. Parmi les neuromodulateurs du système nerveux central, la noradrénaline permettrait de faciliter l'adaptation du comportement face aux variations des contraintes environnementales en modulant l'attention, cette fonction au coeur de la cognition qui nous permet de sélectionner l'information la plus pertinente en fonction de notre but. Ce processus complexe qui opère à chaque instant à la fois dans l'espace et le temps, constitue une étape essentielle dans cette adaptation comportementale. Cependant, à ce jour, les mécanismes par lesquels ce neuromodulateur exerce ses effets sur le cerveau sain demeurent mal connus. Mon travail de thèse a pour objectif d'examiner les déterminants comportementaux et les marqueurs neuronaux de l'effet stimulant des agonistes noradrénergiques. La question posée était : "Comment la noradrénaline agit-elle pour optimiser l'attention?" Pour répondre à cette question, j'ai choisi de combiner la pharmacologie, l'analyse du comportement, et l'imagerie par résonnance magnétique fonctionnelle chez le singe. Un des principaux résultats de mes travaux est que l'administration d'agents noradrénergiques induit une large réorganisation des réseaux cérébraux, qui pourrait être à l'origine de l'optimisation des réponses comportementales observées parallèlementNeuromodulation provides an extraordinary wealth to the dynamics of neural networks. Among the neuromodulators of the central nervous system, noradrenaline would facilitate behavioral adaptation facing variations of environmental constraints by modulating attention, this function at the heart of cognition that allows us to select the most relevant information based our goal. This complex process that operates at every moment both in space and time, is an essential step in this behavioral adaptation. However, to date, the mechanisms by which this neuromodulator exerts its effects on healthy brain remain unknown. My thesis aims to examine the behavioral and neural markers of the boosting effect of noradrenergic agonists. The question asked was: "How does noradrenaline optimize attention?" To answer this question, I chose to combine pharmacology, behavior analysis, and functional Magnetic Resonance Imaging in monkeys. One of the main results of my work is that the administration of noradrenergic agents induced a large-scale brain networks reorganization, which could be responsible for optimizing behavioral responses observed in parallel
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Steinfelder, Svenja. "Immune modulation by parasites." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2007. http://dx.doi.org/10.18452/15682.
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Die Infektion mit Schistosoma mansoni resultiert in einer Th2-Immunantwort mit Eosinophilie und erhöhtem IgE-Titer, wobei der wasserlösliche Extrakt der S. mansoni Eier (SEA) ausreicht um diese Reaktion auszulösen. In der vorliegenden Arbeit konnte demonstriert werden, dass sich IL-4-produzierende CD4+ T-Lymphozyten in Zellkulturen mit SEA-konditionierten Dendritischen Zellen (DCs) trotz gleichzeitig vorkommenden IFN-gamma entwickeln und SEA die Expression von Faktoren in DCs, die üblicherweise mit einer Th1-Antwort einhergehen, auf Transkriptions- und Proteinebene selektiv hemmt. Um den Faktor aus S. mansoni Eiern zu isolieren, der zur Expression von IL-4 in CD4+ Zellen und zur Inhibition von IL-12 in DCs führt, wurde eine Gelfiltrationschromatographie der exkretorisch/sekretorischen Ei-antigene (ES) durchgeführt und die Fraktionen in vitro getestet. Darin wurde gezeigt, dass Fraktionen mit einer Proteinbande von 30 kD die Expression von IL-4 in CD4+ Zellen induzieren. Dieses ES-Protein wurde durch N-terminale Sequenzierung als hepatotoxische Ribonuclease Omega-1 identifiziert, welches ebenfalls die Expression von IL-12 in DCs inhibiert und die Produktion von IL-4 in CD4+ Zellen bei einer 10-fach geringeren Proteinkonzentration als mit dem Kontrollansatz SEA induziert. Zudem sollte untersucht werden, inwieweit Toll-like Rezeptoren in der Generierung einer Th2 Antwort gegen schistosomale Antigene involviert sind. Dazu wurden TLR2-, TLR3-, TLR4- und MyD88-defiziente Mäuse mit S. mansoni infiziert und immunologische und pathologische Daten in der akuten und chronischen Phase der Infektion analysiert. Demnach sind TLR2, TLR3, TLR4 und MyD88-abhängige Signaltransduktionswege nicht für eine-Th2 Antwort notwendig, jedoch ist letzteres Molekül in der Ausprägung der typischen Leberfibrose involviert.Infection with Schistosoma mansoni results in the induction of a Th2 immune response, eosinophilia and increased levels of IgE. The water-soluble extract of S. mansoni eggs (SEA) is sufficient to promote TH2 polarization in a dendritic cell-dependent manner. In this thesis, it was demonstrated that IL-4+ CD4+ cells emerge in cultures with SEA-conditioned dendritic cells (DCs) in the presence of IFN-gamma and that SEA inhibits selectively the expression of IL-12 and co-stimulatory markers in DCs on the transcriptional and protein level. To identify the putative protein in S. mansoni eggs mediating a Th2 induction, a gel filtration chromatography of the excretory/secretory egg antigens (ES) was conducted and the fractions tested in vitro. Fractions containing a single band of 30 kD were sufficient to promote IL-4 induction in naïve CD4+ cells. Using N-terminal sequencing this ES-protein was identified as the hepatotoxic S. mansoni ribonuclease omega-1 which displayed both biological functions observed with SEA: inhibition of IL-12 in LPS-stimulated DCs and induction of IL-4+ CD4 cells at a 10 fold lower protein concentration than SEA. In order to understand, if the innate immune receptors TLR2, TLR3, TLR4 or the TLR adaptor molecule MyD88 are involved in the generation of the Th2 response against schistosomal antigens, the respective knock out mice were infected and immunological and pathological parameters were analyzed during acute and chronic phase of infection. This study showed that during S. mansoni infection TLR2, TLR3, TLR4 and TLR activation through the MyD88-dependent pathway are neither required for the induction (priming and polarization) nor for the down-regulation of Th2 responses, however, the fibrotic response against S. mansoni eggs was significantly reduced in MyD88-deficient mice suggesting a detrimental role of this pathway in liver pathology.
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EBELIN, MARIE-EVE. "Modulation de l'absorption cutanee." Strasbourg 1, 1989. http://www.theses.fr/1989STR15007.
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Obata, Yasunori, and Hiroshi Oguchi. "Commissioning of modulator-based IMRT with XiO treatment planning system." AIP Publishing, 2009. http://hdl.handle.net/2237/20613.
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Remley, Jon Stephen. "The Preferred Oboe Vibrato: An Analysis of Pitch Modulation and Intensity Level Modulation." Thesis, University of North Texas, 1996. https://digital.library.unt.edu/ark:/67531/metadc278116/.
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The purpose of this study was to determine the pitch and intensity level characteristics found in the vibrati of preferred oboe players whose vibrato was ranked by a panel of experts. The investigation also sought to discover factors that distinguish the preferred oboe vibrato from vibrato that is less preferred.
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Pérez, Galacho Diego. "High speed optical modulation, advanced modulation formats and mode division multiplexing in Silicon photonics." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS194/document.
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La demande en bande passante des systèmes de communication optique ne cesse de croitre. Des débits de données de l’ordre de plusieurs centaines de TBit/s sont attendus dans un futur proche. La photonique silicium est une technologie majeure pour faire face à ces besoins croissants. Sa compatibilité avec les technologies CMOS permet naturellement une co-intégration photonique/électronique sur les mêmes circuits. A court terme, l’augmentation des débits de données dans les générations futures de système de communication optique passe par l’utilisation de formats de modulation avancés, et l’augmentation du nombre de bits par symbole transmis. A plus long terme, de nouvelles techniques de multiplexage sont nécessaires. Le multiplexage de modes est actuellement une solution attractive à l’étude dans ce but.Dans ce travail de thèse, différents moyens pour implémenter ces nouveaux systèmes de communication optiques sont étudiés au niveau de l’émetteur. Ces travaux incluent dans une première partie la modélisation, conception et caractérisation des modulateurs silicium. Dans une seconde partie, de nouveaux composants pour manipuler les modes sur circuits intégrés photoniques sont proposés, conçus et caractérisés, avec pour application le multiplexage de modes.Une nouvelle méthode a été proposée pour la modélisation des modulateurs optiques silicium. Cette méthode permet de réduire le temps de simulation de 2 ordres de grandeur, en maintenant un bon niveau de précision. En utilisant ce modèle, des modulateurs basés sur des diodes PN latérales et interdigitées ont été conçus pour fonctionner en bande O des communications optiques. Les résultats expérimentaux ont permis la mise en évidence de diagrammes de l’œil avec des taux d’extinction de 10 dB pour des modulations de type OOK (ON-OFF Keying) à 10Gbit/s. De plus des modulations de type BPSK (Binary Phase Shift Keying) ont également été démontrées à 10Gbit/s.De nouveaux convertisseurs de modes et multiplexeurs ont été proposés, conçus, fabriqués et caractérisés, pour être utilisés dans des systèmes de multiplexage modal. Les résultats expérimentaux ont permis de mettre en évidence des fonctionnements large bande passante avec de grands taux d’extinctionBandwidth demand in optical communication systems is continually growing. Data rate values in the order of several hundreds of TBps are expected in the near future. In order to cope with those expectations silicon based technologies are believed to be the best suited. Its naturally compatibility with CMOS easily enables the electronics and photonics co-integration. In the short-term the way increase data rates in next generation optical communication systems goes through using advanced modulation format and increase symbol rates. In the long-term view, new multiplexing techniques will be required. In this sense, mode division multiplexing is nowadays an attractive approach under consideration.In this Thesis work, the way to implement these new optical communication schemes is studied from the transmitter point of view. It includes, on a first part the modeling, design and characterization of silicon modulators. And in a second part, it includes the proposition, design and characterization of novel mode handling devices for mode division multiplexing.A new way of modeling silicon modulators has been developed. This new model permits to reduce the computation time of modulator analysis up to two orders of magnitude, while maintaining a good level of accuracy. Using the model, modulators based on lateral PN junctions and interdigitated PN junctions were designed to work in the O-Band of optical communications. Characterization work has been performed on these modulators with good results. Wide-open OOK (On Off Keying) eye diagrams with 10 dB extinction ratio were obtained at 10GBps. Furthermore, BPSK (Binary Phase Shift Keying) modulation was also demonstrated at 10GBps.New kind of mode converters and multiplexers, intended to work as mode division multiplexing subsystems have been proposed, designed, fabricated and characterized. Measured results show broad bandwidth operation with high extinction ratio
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Akos, Dennis M. "A hybrid modulation for the VHF aeronautical channels." Ohio : Ohio University, 1992. http://www.ohiolink.edu/etd/view.cgi?ohiou1171473826.
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Wennekamp, Julia [Verfasser], and Philipp [Akademischer Betreuer] Henneke. "Modulation of phagocyte apoptosis by Streptococcus agalactiae = Modulation von Phagozytenapoptose durch Streptococcus agalactiae." Freiburg : Universität, 2011. http://d-nb.info/1123462895/34.
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Ladner, Michael Christopher. "Optical modulator LM 0202 P characteristics : application to amplitude modulation of argon-ion laser." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA313485.
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Hosseini, Seyedreza, and Kambiz Jamshidi. "Modulation efficiency enhancement of an optical phase modulator using one dimensional photonic crystal structures." SPIE, 2015. https://tud.qucosa.de/id/qucosa%3A35320.
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Slow light effect based rib silicon waveguide structures are studied in this paper to enhance modulation efficiency of an optoelectronic carrier plasma dispersion effect based phase modulator. Center frequency to achieve desired slow down factor and band width limitations of the structures are investigated through finite element method simulations. Optical modulation efficiency is modeled and the effects of doping, bias voltage and slow light on its performance are studied.
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Bullard, Jason Mark. "New modulation technique to improve supply ripple rejection of a digital pulse width modulator." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0007548.
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Dumenil, Arnaud. "Polarization dependent loss in next-generation optical networks : challenges and solutions." Electronic Thesis or Diss., Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAS006.
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La demande de débit en augmentation constante requiert des canaux de communication fiables et robustes. Les réseaux optiques terrestres ainsi que les liens sous-marins représentent le cœur de l'infrastructure des télécommunications au niveau mondial, et transportent des centaines de canaux fréquentiels modulés à haut débit. Ces liens se composent non seulement de kilomètres de fibre mais aussi de composants optiques comme les amplificateurs à fibre dopée à l'erbium (EDFA) pour relever régulièrement la puissance des signaux atténués, ou encore des commutateurs sélectifs en longueur d'onde (WSS) qui routent le signal vers leur destination. Dans cette thèse, nous nous intéressons à une pénalité spécifique qui survient dans ces systèmes et qui réduit le débit d'information dans une propagation optique. Les composants optiques discrets présentent typiquement une anisotropie en polarisation : un déséquilibre de perte (ou gain) apparaît entre les deux polarisations d'un signal optique multiplexé en polarisation. Cet effet non unitaire appelé pertes dépendant de la polarisation (abrégé PDL en anglais) dégrade la qualité de transmission dans les systèmes optiques actuels et futurs.Dans le cadre des transmissions multiplexés en polarisation, nous caractérisons la perte de capacité induite par la PDL. Pour commencer, des modèles de canal sont attentivement étudiés et deux approches sont présentées : un canal avec des éléments PDL distribués avec un bruit également distribué, ou alors un canal équivalent simplifié en un seul élément. Nous analysons les limites fondamentales de communication associées à ces modèles. Nous montrons en outre que la capacité d'un canal PDL dépend en pratique de l'orientation de l'état de polarisation du signal incident. Nous passons ensuite en revue l'état de l'art de schémas de modulation atténuant l'effet de PDL puis nous proposons deux nouveaux schémas de modulation multi-dimensionnels qui augmentent la performance minimum et moyenne du canal. Ces deux modulations sont des transformations unitaires de symboles M-QAM qui n'utilisent pas de degrés de liberté autres que les quatre déjà utilisés pour chaque longueur d'onde (encodage en phase et quadrature de phase sur les deux états de polarisation). Nous proposons succinctement une extension de ces premiers résultats à des communications optiques plus généralement multiplexés en dimension spatiale et impactées par des pertes dépendantes de mode, qui présentent un déséquilibre de gain identique. Au-delà de la construction de modulations au niveau du transmetteur, nous étudions la perte de performance en présence de PDL d'une chaîne de traitement de signal conventionnelle et séquentielle par comparaison avec une égalisation et décodage joint. Cette perte additionnelle de capacité résultant du traitement séquentiel non optimal est évaluée pour différents formats de modulations ainsi que différents points de fonctionnement. Enfin, nous exposons une validation expérimentale des deux schémas de modulation proposés, aussi bien sur un élément de PDL seul ou sur un canal PDL distribué, et montrons comme attendu une robustesse augmentée vis-à-vis de la PDLLarge amounts of ever-increasing global data traffic require sound and reliable communication channels. Optical terrestrial networks and submarine links are at the very heart of the global telecom infrastructure, and carry hundreds of frequency channels modulated at very high rates. These links include not only kilometers of fiber but also optical elements such as Erbium-Doped Fiber-Amplifiers (EDFA) to amplify periodically the attenuated signals and Wavelength Selective Switches (WSS) to route the signals to their assigned destinations. In this thesis, we explore a specific rate-degrading impairment of the optical propagation that raises in those systems. Discrete optical elements often exhibit a polarization anisotropy that emerges as a gain or loss imbalance between the two polarization tributaries of the polarization-multiplexed optical signals. This non-unitary effect called Polarization Dependent Loss (PDL) impairs the quality of transmission in current and next-generation optical systems.In the context of polarization-multiplexed signals, we assess the capacity loss induced by PDL. First, channel models are carefully studied and two approaches are described: a channel with distributed PDL elements and distributed noise or a simplified single-element equivalent channel. Making use of these models, we then analyze their fundamental limits of communications. We show that the PDL channel capacity depends in practice on the state-of-polarization orientation of the incident signal. We then review the state-of-the art of PDL-mitigating modulation schemes and propose two new multi-dimensional signaling schemes that enhance worst-case and average performance. These two modulations are unitary transforms of M-QAM symbols and do not make use of additional degrees of freedom apart from the four already-used dimensions per wavelength (in-phase and quadrature channels of two polarization states). We briefly extend these first results to space-division-multiplexed optical communications impaired by mode dependent loss (MDL) that present a similar gain imbalance. Beyond signal shaping at the transmitter side, we study the performance loss of a conventional, sequential signal processing chain at the receiver side in presence of PDL, in comparison with a joint equalization-decoding scheme. The additional capacity loss due to the mismatch sequential processing is evaluated for several modulation formats and at different operating points. Finally, we report an experimental validation of the two proposed signaling schemes, both on a single PDL element and on a distributed PDL channel, demonstrating the predicted enhanced robustness to PDL
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Khayatian, Alireza. "Multirate and block methods for modeling and control of pulse modulated systems." Diss., Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/13761.
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Hof, Axel. "On concatenated coding schemes employing trellis coded modulation." Düsseldorf VDI-Verl, 2009. http://d-nb.info/994364539/04.
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Gebhardt, Heidi L. "Communication modulation simulators : an assessment." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1997. http://handle.dtic.mil/100.2/ADA333341.
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Thesis (M.S. in System Technology (Command, Control and Communications)) Naval Postgraduate School, June 1997.Thesis advisors, John S. Osmundson, Donald v.Z. Wadsworth. Includes bibliographical references (p. 59). Also available online.
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Thompson, Steve C. "Constant envelope OFDM phase modulation /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2005. http://wwwlib.umi.com/cr/ucsd/fullcit?p3208635.
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Weigmann, Benno. "Analyse und Modulation kontaktallergischer Reaktionen." [S.l.] : [s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=964883643.
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Chen, Hang. "Modulation Effects on Organic Electronics." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7594.
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A high aspect ratio epoxy mask has been built with Taiyo PSR4000BN on chemical sensing array chip. Thickness up to 200 and #61549;m and aspect ratio up to 16:1 have been achieved with this material. It is demonstrated that this material satisfies the mechanical and chemical requirements. A three-electrode system has been designed and built for electrochemistry in micro-cell on chip. Tests with poly(phenylenesulfide-phenyleneamine) (PPSA) demonstrates that it is possible to precisely tune the properties (Work function and resistance) of conducting polymer that has been cast on chip surface.
A new test platform GT03 has been fabricated and used to characterize the chemical effects on organic electronics. It is demonstrated that the chemical species in ambient environment can affect organic electronics properties on bulk, interface and electric contact. The contact resistance in organic field-effect transistors (OFETs) has been characterized with modified interdigitated structure (IDS). It is demonstrated that drain and source contact resistances can be calculated separately with modified four-point-probe measurements, and contact resistance and material bulk resistance are actually modulated by the gate electric field. Furthermore, the influence from oxygen doping in poly(3-hexylthiophene) (P3HT) based OFETs has been investigated. A new model of oxygen doping has been suggested and it is demonstrated that oxygen doping can affect all the resistance components in P3HT OFETs.
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Ozturk, Uygar. "Chaotic Digital Modulation And Demodulation." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/2/12606895/index.pdf.
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This thesis considers a communication system with chaotic modulation. Noise-like signals are generated by chaotic systems with different parameters to modulate binary digital signals. Demodulation is performed by both the Extended Kalman Filter (EKF) and Optimum Decoding Based Smoothing Algorithm (ODSA). Simulations are performed using both of these algorithms for different parameters affecting the performance of the communication system. Simulation results of these algorithms are compared.
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Chu, Haobing. "Is spiral modulation really useful?" Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/60140.
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The performance analysis of modulation techniques has been studied extensively. In this thesis, we investigate the performance of a new modulation technique called spiral modulation. Spiral modulation uses complex spirals in the complex plane to modulate data and form complex signals. Spiral modulation was proposed by Astrapi Corporation and the company claimed that spiral modulation is better than the conventional modulations and can exceed the Shannon limit. In this thesis, we explore the potential of spiral modulation and verify the claims by using MATLAB simulation according to the Astrapi's spiral modulation patents. We first present the system structure and the concept of spiral modulation. Then, we focus on the bit-error rate (BER) performance analysis and the spectral efficiency analysis by using MATLAB simulation. In the BER performance analysis, our simulation results reveal that the BER performance of spiral modulation can be better than some conventional modulations when the constellation size is equal or larger than eight if the bandwidth is not taken into consideration. In the spectral efficiency analysis, we estimate the bandwidth of spiral modulation signals by using the periodogram method. The results show that the bandwidth of spiral modulation signal is not strictly limited. A spectral efficiency plane is plotted, and it shows that the spectral efficiency of spiral modulation is worse than the conventional modulation techniques. We conclude that, contrary to the claim made by Astrapi, the spiral modulation can not exceed Shannon capacity boundary on the spectral efficiency plane.Applied Science, Faculty of
Engineering, School of (Okanagan)
Graduate
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Heasman, Sarah Jane. "Glucocorticoid modulation of macrophage function." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/29146.
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In this thesis, I have examined the effects of glucocorticoid-treatment of peripheral blood monocytes which has previously been demonstrated to markedly augment phagocytic capacity for apoptotic cells, an effect which may contribute to anti-inflammatory actions of glucocorticoids. Within the inflammatory site, the cytokine environment governs the differentiation and function of infiltrating leukocytes. I have investigated the effects of combinatorial treatment of monocytes with the principal Th1 and Th2 cytokines, IFN-γ and IL-4. I have demonstrated that whilst glucocorticoids exert a dominant effect over those of IFN-γ in terms of cell morphology and cell surface receptor expression, glucocorticoid-augmented phagocytosis of apoptotic neutrophils is inhibited by IFN-γ. These findings suggest that the effectiveness of glucocorticoids in promoting a highly phagocytic macrophage phenotype is crucially dependent on the cytokine milieu at inflammatory sites. Cellular migration is an important determinant for the initiation of inflammatory responses and for the resolution phase, where macrophages migrate to draining lymph nodes. My results provide evidence for an alteration in the adhesion and migration of macrophages following glucocorticoid treatment. I have demonstrated changes in cytoskeletal organisation and assembly/engagement of Rho family GTPase signalling pathways. These changes may influence macrophage migration patterns that are important for the progression of inflammatory responses. Together, the studies presented in this thesis suggest that glucocorticoids exert profound effects upon macrophage cytoskeletal organisation that influences both phagocytosis and migration and may also cause a switch in apoptotic cell recognition mechanisms.
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Cojocaru, Alice. "Cytoskeletal modulation of surfactant trafficking." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ34059.pdf.
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Jiang, Yan Jenny. "Modulation of cytosolic phospholipase A2." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0016/MQ51726.pdf.
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Sharma, Gaurav. "Adaptive modulation for cognitive radios." Diss., Rolla, Mo. : University of Missouri--Rolla i.e. [Missouri University of Science and Technology], 2008. http://scholarsmine.mst.edu/thesis/pdf/Sharma_09007dcc8046bf0b.pdf.
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Thesis (M.S.)--Missouri University of Science and Technology, 2008.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed February 13, 2008) Degree granted by Missouri University of Science and Technology, formerly known as University of Missouri--Rolla. Includes bibliographical references (p. 44-45).
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Ayres, Mark Randall. "Signal modulation for holographic memories." Connect to online resource, 2007. 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:3284466.
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