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Nonlinear microscopy has become an indispensable tool in the study of biological systems. It includes many nonlinear contrast mechanisms, each sensitive to different biological structures. However, interpretation of the images generated in nonlinear microscopy is a complex matter due to factors such as the structural complexity of the sample, phase relationships between the excitation beam and the detected signal and the nonlinear interactions in the focal volume of the microscope. This thesis contains a new theoretical and numerical framework that describes the focusing of an excitation beam in a nonlinear microscope, the nonlinear optical interactions with the material in the focal volume, and the resulting nonlinear optical signal in the far field. The framework is the first to include reflection and refraction of the excitation beam and nonlinear signals by an arbitrary number of interfaces in the focal volume, which is especially significant for the interpretation of third harmonic generation (THG). It also uses the chirp-z transform to speed up calculations by orders of magnitude compared to numerical integration techniques. The framework is used to investigate second harmonic generation (SHG) by collagen. Focusing effects alter polarization-dependent SHG measurements of collagen properties compared to the plane wave approximation, and this is verified experimentally. Furthermore, a technique of imaging the far field SHG radiation from collagen fibres is proposed, which can be used to extract the orientation of collagen fibres unambiguously. The framework is then applied to analyze the influence of interfaces on THG. Reflection effects at interfaces significantly affect THG, which leads to the development of a new super-resolution THG imaging technique based on backward-propagating THG. This super-resolution technique is experimentally demonstrated by imaging surface profiles with tens of nanometers resolution, which is the first time that such resolution is obtained in coherent nonlinear microscopy. Therefore, this imaging technique shows promise to become an important tool in high-resolution imaging of (biological) samples. The theoretical and numerical framework provides a foundation for future research on the origin of nonlinear microscopy signals. The new imaging techniques based on this framework have great potential in quantifying fibrillar structures and interfaces in biological samples.

Femtosecond time scale allows us to follow and control atomic and molecular motion. The atomic vibrations happen in the range of femtosecond scale. Thus, femtosecond technology effectively measures the atomic vibration. However, to determine electron motion, one needs to reach sub-femtosecond time scale that is in attosecond time scale. High Harmonic Generation (HHG) is a non-linear process that converts infrared light to shortest wavelength, such as in the XUV regime. HHG allows to explore electronic motion and to control electron dynamics. HHG easily reaches to XUV region and is enabling attosecond pulse generation. In this thesis we focused to generate attosecond pulses by using noble gases and their mixtures. We used only argon gas, only hydrogen molecule and their mixture with neon gas. We wanted to improve the conversion efficiency (10^-6) of the fundamental light into high harmonics. We use Ne and H2 gas mixture to look enhancement of the HHs.

The availability and use of new materials and construction techniques are allowing bridges to be built that are longer and more slender to those that have been constructed in the past. This can cause bridges to have lower stiffness and damping, and thus be less able to resist dynamic effects. This is of special concern for pedestrian bridges, because the harmonic loads that pedestrians apply to the bridge have the potential to excite the bridge’s natural frequencies. In addition, pedestrians can be sensitive to these vibrations. A model was developed in order to better understand the effects that a pedestrian can have on these vibration-prone bridges. The model consisted of two parts: a finite element model that used the structural data for the bridge in order to produce mass-normalized mode shapes, and a bridge-pedestrian interaction program that used the structural and modal data, along with pedestrian loading scenarios, to generate the bridge response. A parametric study of two bridges was conducted. The bridges included: a short span bridge that would not be expected to respond excessively to pedestrian loads, and a long-span, lively bridge that had natural frequencies in the range of pedestrian loading. Many loading cases were examined by varying the following parameters: load case, number of pedestrians, damping, and pacing frequency. The modal solution was an effective method of finding the bridge responses. It was determined that pedestrian loads can be represented by a simple constant plus sinusoidal load. The excessive vibrations of long and slender bridges could be addressed by increasing damping on susceptible modes. / Thesis (Master, Civil Engineering) -- Queen's University, 2010-05-03 12:36:05.561

This thesis suggests an approach to compute the short-time behaviour of the hypoelliptic heat kernel corresponding to sub-Riemannian structures on unimodular Lie groups of type I, without previously holding a closed form expression for this heat kernel. Our work relies on the use of classical non-commutative harmonic analysis tools, namely the Generalized Fourier Transform and its inverse, combined with the Trotter product formula from the theory of perturbation of semigroups. We illustrate our main results by computing, to our knowledge, a first expression in short-time for the hypoelliptic heat kernel on the Engel and the Cartan groups, for which there exist no closed form expression. / Thesis (Master, Mathematics & Statistics) -- Queen's University, 2011-10-08 01:32:32.896

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The opera bouffe Les mamelles de Tiresias (1944) by Francis Poulenc (1899-1963) stands at the crossroad between the composer's formative and mature works. The opera exhibits a number of harmonic features characteristics of Poulenc's eclectic, idiosyncratic style. This thesis attempts to address the lack of attention given this work in particular and Poulenc's output in general. / The thesis consists of two volumes. Volume I contains the introduction, three chapters and the conclusion. Volume 2 contains musical examples, analytical graphs and reproductions of Act 1, Scenes 1 and 2, and Act 2, Scenes 7 and 8 from the piano-vocal score of Les mamelles de Tiresias. / The first chapter of Volume 1 reviews two Ph.D. dissertations that examine Poulenc's harmonic language; and summarizes the more recent analyses by Vivan Wood, Pamela Poulin and Keith Daniels. Figures (the musical examples) for Chapter 1 are given in Volume 2. / Chapter 2 of Volume 1 examines the large-scale harmonic organization in pivotal scenes that are representative of the musical language in the opera. / Chapter 3 of Volume I extends Warren Werner's and Richard Bobbitt's approach to show how local events and large-scale harmonic motions can be viewed as leitmotives that symbolize key events in the drama. Figures (the musical examples) and Graphs (the analytical graphs) for Chapter 3 are given in Volume 2. / The conclusion reviews there observations of the study and makes some general remarks about Poulenc's harmonic language. (Abstract shortened by UMI.)

Optical imaging has been developed quickly in the past decades because it has become an important research tool in biology, biochemistry, and biomedical sciences. Coherence domain optical imaging is one of the well developed optical imaging modalities, as it provides high resolution and long penetration depth. In this dissertation, we will report our work on development of molecular contrast in coherence domain optical imaging. In order to image important molecules which are poor fluorophores, we developed a high resolution molecular imaging technique, pump-probe optical coherence microscopy (PPOCM), which does not rely on fluorescent tags. PPOCM is the fusion of Pump-Probe spectroscopy and optical coherence microscopy (OCM). We have demonstrated the prototype system on a fixed human skin sample containing a nodular melanoma. The results indicate that PPOCM can clearly provide strong contrast between the melanotic and amelanotic regions. This technique can be applied to early diagnosis of melanoma and the mapping of tumor margins during excision. It also can be extended to any biological chromophore with a known absorption spectrum and sufficient concentration. In order to differentiate further multiple chromophores, we developed a spectrally resolved two color pump-probe Optical Coherence Microscopy (SRPPOCM). We showed the prototype system on a red hair and a black hair. Our preliminary results show that the SRPPOCM technique could provide a contrast between pheomelanin and eumelanin. This technique could be used potentially as a clinical tool for diagnosing different progression stages of melanoma. This technique could also be applied to differentiate other mixed chromophores. Second harmonic optical coherence tomography (SHOCT) is non-linear high resolution optical molecular imaging modality which is widely used in non-centrosymmetric material. However, depth ambiguity is associated with SHOCT in tissue sample because forward generated second harmonic signal does not correctly report where the second harmonic signal is generated. We studied the feasibility of collecting the backward generated second harmonic signal from nanocrystals through a Second Harmonic Optical Coherence Tomography in Fourier domain. The preliminary result shows that we can collect backward generated second harmonic signal from nanocrystals which indicates that this technique could suppress the depth ambiguity.

Title:EFFECTS OF THE PROMINENCE OF FIRST HARMONIC ON THE PERCEPTION OF BREATHINESS AND VOWEL IDENTITY Authors: Emily Lin, Samuel Sloane,and Donal Sinex Background: Human communication relies on adequate speech intelligibility to enable the comprehension of verbal messages. Dysphonia (i.e., aberrant voice) may not only result in distraction during communication but also interfere with speech intelligibility leading to a communication barrier. One voice quality commonly found in dysphonia is breathiness, which is related to the presence of excessive airflow during phonation due to incomplete glottal closure. Breathiness has been associated with the prominence of the first harmonic (H1) in the acoustic analysis of voice. Objectives: This study aimed to determine whether excessiveness in the first harmonic (H1) dominance, which has been associated with breathy voice, may result in the perception of breathiness and compromise vowel intelligibility. Methods: Participants included 10 female and 10 male normal-hearing adults, aged between 19 to 40 years. Participant’s tasks included a “breathiness rating” and a “vowel identification” task. For the “breathiness rating” task, a direct magnitude method was employed for the participant to rate a 500-ms long vowel (/i/ and /a/) segmented from sustained vowel phonation. For the “vowel identification” task, the vowel stimuli were segmented out from running speech (“Rainbow passage”) and the participants were asked to listen to one vowel stimulus (/i/, /a/, or /o/; duration: 60 ms) at a time and indicate which vowel (i.e., /i/, /e/, /a/, /o/, or /u/) they perceived the stimulus to be. The vowel stimuli included processed and unprocessed voice recordings of individuals with and without voice disorders. Voices showing the lowest, median, and highest amplitude differences between the first two harmonics (H1-H2) were chosen from a voice database for female and male voices respectively. The 18 selected vowel signals (3 vowels X 3 H1-H2 levels X 2 speaker genders) were processed through 12 signal manipulation conditions. The 12 signal conditions involved increasing or decreasing the H1 amplitude of the original signals in six 2-dB interval steps in both directions. Results: For the “breathiness rating” task, the five-way (3 vowels X 2 speaker genders X 3 H1-H2 levels X 13 signal conditions X 2 listener genders) Mixed Model Analysis of variance (ANOVA) conducted on the breathiness scores for normal speakers and voice patients separately showed significant findings for various main and interaction effects, such as a significant speaker gender by signal condition by vowel interaction effect on the perception of breathiness [F(12, 96) = 1.95, p = 0.038] for normal voice. An increase of H1-H2 through signal manipulation led to an increase of perceived breathiness only when performed on the vowel /i/ produced by female normal speakers. As for the “vowel identification” task, a relationship between H1-H2 increment and vowel intelligibility was found but the relationship was affected by vowel type, speaker gender, and H1-H2 level. With all vowel types, speaker genders, and H1-H2 levels combined, a significant signal condition effect on the number of incorrect vowel identification was found (2 = 188.585, df = 10, p < 0.001). Generally, it appeared that an increase of H1-H2 would worsen the identification of /i/ but enhance that of /o/. Conclusion: The relationship between H1 dominance and perceived breathiness was non-linear. Factors found to disrupt the linear relationship included speaker gender, vowel type, and the extent of H1 dominance. In addition, there was evidence that acoustic manipulation of the H1 amplitude would affect vowel intelligibility and the relationship between vowel intelligibility and H1-H2 values also vary by speaker genders and vowel types.

This thesis describes the algorithms and techniques developed for harmonic state estimation and transient state estimation, which can be used to identify the location of disturbance sources in an electrical power system. The previous harmonic state estimation algorithm is extended to include the estimation of time-varying harmonics using an adaptive Kalman filter. The proposed method utilises two covariance noise models to overcome the divergence problem in traditional Kalman filters. Moreover, it does not require an optimal covariance noise matrix of the Kalman filter to be used. The common problems faced in harmonic state estimation applications due to the influence of measurement bad data associated with measurements and the lack of measurement points, hence the system being partially observable, are investigated with reference to the Lower South Island of the New Zealand system. The state estimation technique is also extended to transient state estimation. Two formulation methods are outlined and the development of the proposed methodology is presented. Fault scenarios with reference to the Lower South Island of the New Zealand system are simulated to demonstrate the ability of transient state estimation in estimating the voltages and currents of the unmeasured locations, and applying the estimated results to search for the fault location. The estimation results are compared with PSCAD/EMTDC simulations to justify their accuracy.