published_or_final_version / abstract / Biological Sciences / Doctoral / Doctor of Philosophy

This work presents the design, development, and testing of a field portable imaging spectropolarimeter that operates over the short-wavelength and middle-wavelength portion of the infrared spectrum. The sensor includes a pair of sapphire Wollaston prisms and several high order retarders to produce the first infrared implementation of an imaging Fourier transform spectropolarimeter, providing for the measurement of the complete spectropolarimetric datacube over the passband. The Wollaston prisms serve as a birefringent interferometer with reduced sensitivity to vibration when compared to an unequal path interferometer, such as a Michelson. Polarimetric data are acquired through the use of channeled spectropolarimetry to modulate the spectrum with the Stokes parameter information. The collected interferogram is Fourier filtered and reconstructed to recover the spatially and spectrally varying Stokes vector data across the image.The intent of this dissertation is to provide the reader with a detailed understanding of the steps involved in the development of this infrared hyperspectral imaging polarimeter (IHIP) instrument. First, Chapter 1 provides an overview of the fundamental concepts relevant to this research. These include imaging spectrometers, polarimeters, and spectropolarimeters. A detailed discussion of channeled spectropolarimetry, including a historical study of previous implementations, is also presented. Next a few of the design alternatives that are possible for this work are outlined and discussed in Chapter 2. The configuration that was selected for the IHIP is then presented in detail, including the optical layout, design, and operation. Chapter 3 then presents an artifact reduction technique (ART) that was developed to improve the IHIP's spectropolarimetric reconstructions by reducing errors associated with non-band-limited spectral features. ART is experimentally verified in the infrared using a commercial Fourier transform spectrometer in combination with Yttrium Vanadate as well as Cadmium Sulfide retarders.The remainder of this dissertation then details the testing and analysis of the IHIP instrument. Implementation of ART with the IHIP as well as the employed calibration techniques are described in Chapter 4. Complete calibration of the IHIP includes three distinct processes to provide radiometric, spectral, and polarimetric calibration. With the instrument assembled and calibrated, results and error analyses are presented in Chapter 5. Spectropolarimetric results are obtained in the laboratory as well as outdoors to test the IHIP's real world functionality. The performance of the instrument is also assessed, including experimental measurement of signal-to-noise ratio (SNR), and an analysis of the potential sources of systematic error (such as retarder misalignment and finite polarizer extinction ratio). Chapter 6 presents the design and experimental results for a variable Wollaston prism that can be added to the IHIP to vary the fringe contrast across the field of view. Finally, Chapter 7 includes brief closing remarks summarizing this work and a few observations which may be useful for future infrared imaging Fourier transform channeled spectropolarimeter instruments.

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International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / In many signal processing and telemetry applications only a portion of the Discrete Fourier Transform (DFT) of a data sequence is of interest. This paper develops an algorithm which enables computation of the FFT only over the frequency values of interest, reducing the computational complexity. As will be shown, the algorithm is also very modular which lends to efficient parallel processing implementation. This paper will begin by developing the frequency selective FFT algorithm, and conclude with a comparative analysis of the computational complexity of the algorithm with respect to the traditional FFT.

Ultrasonic technology is commonly used in the eld of Non-Destructive Testing (NDT) of metal structures such as steel, aluminium, etc. Compared to ultrasonic bulk waves that travel in infinite media with no boundary influence, Ultrasonic Guided Waves (UGWs) require a structural boundary for propagation such that they can be used to inspect and monitor long elements of a structure from a single position. The greatest challenges for any UGW system are the plethora of wave modes arising from the geometry of the structural element which propagate with a range of frequency dependent velocities and the interpretation of these combined signals reflected by discontinuities in the structural element. In this thesis, a technique is developed which facilitates the measurement of Time of Arrival (ToA) and group velocity dispersion curves of wave modes for one dimensional structures as far as wave propagation is concerned. A second technique is also presented which employs the dispersion curves to deliver enhanced range measurements in complex multimodal UGW responses. Ultimately, the aforementioned techniques are used as a part of the analysis of previously unreported signals arising from interactions of UGWs with piezoelectric transducers. The first signal processing technique is presented which used a combination of frequency-sweep measurement, sampling rate conversion and the Fourier transform. The technique is applied to synthesized and experimental data in order to identify different wave modes in complex UGW signals. It is demonstrated that the technique has the capability to derive the ToA and group velocity dispersion curve of the wave modes of interest. The second signal processing technique uses broad band excitation, dispersion compensation and cross-correlation. The technique is applied to synthesized and experimental data in order to identify different wave modes in complex UGW signals. It is demonstrated that the technique noticeably improves the Signal to Noise Ratio (SNR) of the UGW response using a priori knowledge of the dispersion curve. It is also able to derive accurate quantitative information about the ToA and the propagation distance. During the development of the aforementioned signal processing techniques, some unwanted wave-packets are identified in the UGW responses which are found to be induced by the coupling of a shear mode piezoelectric transducer at the free edge of the waveguide. Accordingly, the effect of the force on the piezoelectric transducers and the corresponding reflections and mode conversions are studied experimentally. The aforementioned signal processing techniques are also employed as a part of the study. A Finite Element Analysis (FEA) procedure is also presented which can potentially improve the theoretical predictions and converge to results found in experimental routines. The approach enhances the con dence in the FEA models compared to traditional approaches. The outcome of the research conducted in this thesis paves the way to enhance the reliability of UGW inspections by utilizing the signal processing techniques and studying the multimodal responses.

The ocean and acoustic modeling community has specifically asked for roughness from bathymetry. An effort has been undertaken to provide what can be thought of as the high frequency content of bathymetry. By contrast, the low frequency content of bathymetry is the set of contours. The two-dimensional amplitude spectrum calculated with the nonequispaced fast Fourier transform (Kunis, 2006) is exploited as the statistic to provide several parameters of roughness following the method of Fox (1996). When an area is uniformly rough, it is termed isotropically rough. When an area exhibits lineation effects (like in a trough or a ridge line in the bathymetry), the term anisotropically rough is used. A predominant spatial azimuth of lineation summarizes anisotropic roughness. The power law model fit produces a roll-off parameter that also provides insight into the roughness of the area. These four parameters give rise to several derived parameters. Algorithmic accomplishments include reviving Fox’s method (1985, 1996) and improving the method with the possibly geophysically more appropriate nonequispaced fast Fourier transform. A new composite parameter, simply the overall integral length of the nonlinear parameterizing function, is used to make within-dataset comparisons. A synthetic dataset and six multibeam datasets covering practically all depth regimes have been analyzed with the tools that have been developed. Data specific contributions include possibly discovering an aspect ratio isotropic cutoff level (less than 1.2), showing a range of spectral fall-off values between about -0.5 for a sandy- bottomed Gulf of Mexico area, to about -1.8 for a coral reef area just outside of the Saipan harbor. We also rank the targeted type of dataset, the best resolution gridded datasets, from smoothest to roughest using a factor based on the kernel dimensions, a percentage from the windowing operation, all multiplied by the overall integration length.

Objetivou-se com este trabalho avaliar a utilização da metodologia no infravermelho com Transformada de Fourier (ITF) na determinação do pH e ponto de congelamento (PC) no leite bovino. No primeiro estudo foram avaliados os efeitos das diferentes condições de conservação em amostras de leite para posterior análise do pH e do PC. Para tanto, foram coletadas, do tanque de 57 propriedades, amostras de três litros de leite. Cada amostra foi subdividida e transferida para 45 frascos de 40mL e distribuídas de acordo com a temperatura de armazenamento (-30C° - Congelado; 7°C - Resfriado; 25°C - Ambiente), idade da amostra (0, 3, 6 e 9dias) e níveis de adição de água (0, 2, 4 e 6%). Foram adicionadas pastilhas de bronopol (Microtabs®) aos 44 frascos, sendo que um foi mantido sem adição do conservante para tratamento controle. Os resultados obtidos, considerando as diferentes condições de conservação das amostras, e ainda, o efeito da adição do bronopol, foram avaliados por comparação de médias. As metodologias (referência e alternativa) foram correlacionadas em função da idade da amostra para o PC por análise de regressão linear. A sensibilidade e a especificidade foram calculadas para avaliação do desempenho do equipamento MilkoScanTM FT+ na detecção de água. A adição do bronopol não alterou as médias do pH, porém reduziu significativamente o PC. Para eliminação desse efeito, foram calculados fatores de correção para os resultados do PC nas duas metodologias empregadas nesse estudo. O aumento da temperatura de armazenamento reduziu significativamente as médias do pH e do PC em amostras com seis e nove dias de coleta. Não houve efeito significativo nas médias do pH e do PC com o aumento na idade da amostra a -30° e 7°C. As correlações entre as metodologias em função da idade da amostra para o PC foram altas e significativas. A sensibilidade e especificidade do equipamento MilkoScanTM FT+ na detecção de água, em relação ao crioscópio eletrônico, foram de 90,9% e de 86,8%, respectivamente. No segundo estudo, objetivou-se caracterizar a atual situação do ponto de congelamento (PC) em rebanhos brasileiros, e avaliar o efeito da lactose e da contagem bacteriana total (CBT) sobre os resultados do PC. Foram analisados 137.443 dados por meio de estatística descritiva e de análise da variância, para caracterizar a atual situação do PC e para avaliação dos efeitos da lactose e da CBT sobre o PC. A média e o respectivo desviopadrão do PC foi de -0,522 (0,011)°C, e, constatou-se que o percentual de amostras em conformidade com a Instrução Normativa nº 51 foi de 92,48%, enquanto que para amostras em não conformidade, com indicativo de adição de água ou de soluto, foi de 7,10% e 0,41% respectivamente. A lactose e a CBT influenciaram significativamente nos níveis do PC. / The objective of this study was to evaluate the use of the methodology Fourier Transform Infrared (FTIR) for determining the pH and freezing point (FP) in bovine milk. The first study evaluated the effects of different storage conditions on samples of milk for subsequent analysis of pH and the PC. For both, were collected from the tank of 57 properties, samples of three liters of milk. Each sample was divided and transferred to 45 vials of 40mL and distributed according to storage temperature (-30C°- Frozen, 7°C - Cold, 25°C - Environment), age of the sample (0, 3, 6 and 9 days) and levels of added water (0, 2, 4 and 6%). Tablets to bronopol (Microtabs®) were added to 44 bottles, of which one was maintained without addition of preservative for control treatment. The results, considering the different conditions of storage of samples, and the effect of adding bronopol were evaluated by comparison of means. The methods (reference and alternative) were correlated with age of the sample to the FP for linear regression analysis. The sensitivity and specificity were calculated to evaluate the performance of MilkoScanTM FT+ equipment for detecting water. The addition of bronopol did not alter the average pH, but significantly reduced the FP. To combat this effect, were calculated correction factors for the results of the PC in the two methodologies employed in this study. Increasing the temperature of storage significantly reduced the average pH and the FP samples with six and nine days of collection. There was no significant effect on mean pH and the PC with the increasing age of the sample at -30°C and 7°C. The correlations between the methods depending on the age of the sample for the FP were high and significant. The sensitivity and specificity of the equipment MilkoScanTM FT+ in the detection of water on the thermistor cryoscope were 90.9% and 86.8% respectively. While in the second study aimed to characterize the current state of the freezing point (FP) in Brazilian herds and Evaluated the effect of lactose and the total bacterial count (TBC) on the results of the FP. 137,443 data were analyzed using descriptive statistics and analysis of variance, to characterize the current state of the FP and to evaluated the effects of lactose and TBC on the FP. The mean and standard deviation of the FP was -0.522 (0.011)°C, and it was found that the percentage of samples in accordance with Normative Instruction nº 51 was 92.48%, while for samples not in accordance with an indication of added water and solute was 7.10% and 0.41% respectively. The lactose and TBC significantly influenced the levels of PC.

Sze Tung Po Eric. / "Mar 2000." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

by Siu-wang Lau. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 121-127). / Abstracts in English and Chinese. / Contents page / Acknowledgement --- p.ii / Abstract --- p.iii / Abbreviations --- p.v / Contents --- p.vi / Introduction --- p.1 / Chapter Part I / Chapter 1 --- Principle of Fourier transform infrared spectroscopy (FTIR) --- p.9 / Chapter 2 --- Experimental --- p.15 / Chapter 2.1 --- Method of calibration curve for FTIR --- p.15 / Chapter 2.2 --- Method of standard addition for FTIR 18 、 / Chapter 3 --- Results --- p.19 / Chapter 3.1 --- Results of the method of calibration curve for FTIR --- p.26 / Chapter 3.2 --- Results of the method of standard addition for FTIR --- p.34 / Chapter 4 --- Discussion --- p.37 / Chapter 5 --- Interferences between the major components when two standard chemicals were considered each time (mixture of two standard compounds) --- p.41 / Chapter 5.1 --- Introduction --- p.41 / Chapter 5.2 --- Procedures --- p.43 / Chapter 5.3 --- Results --- p.47 / Chapter 5.4 --- Discussion --- p.80 / Chapter 6 --- Interferences between the major components when four standard chemicals were considered each time (mixture of four standard compounds) --- p.83 / Chapter 6.1 --- Introduction --- p.83 / Chapter 6.2 --- Experimental --- p.83 / Chapter 6.3 --- Results --- p.85 / Chapter 6.4 --- Conclusion --- p.89 / Chapter 7 --- Discussion --- p.90 / Chapter Part II / Chapter 1 --- Introduction --- p.92 / Chapter 2 --- Principle of flame emission spectroscopy (FES) --- p.92 / Chapter 3 --- Introduction of the analysis of total calcium by FES --- p.94 / Chapter 4 --- Experimental --- p.104 / Chapter 4.1 --- Methods of digestion --- p.104 / Chapter 4.2 --- Methods of oxidation --- p.105 / Chapter 4.3 --- Calibration of standard --- p.106 / Chapter 5 --- Results --- p.107 / Chapter 6 --- Discussion --- p.112 / Chapter Part III / Chapter 1 --- Estimation of total calcium by FTIR --- p.113 / Chapter 2 --- Experimental --- p.113 / Chapter 3 --- Results --- p.115 / Chapter 4 --- Discussion --- p.119 / Chapter Part IV --- Conclusion --- p.120 / Chapter Part V --- References --- p.121 / Appendices / Appendix 1 Example of the calculation of analyte content by the method of calibration curve --- p.128 / Appendix 2 Examples of the calculations of the analytes by the method of standard addition --- p.130 / Appendix 3 IR spectrum of a mixture of four standard chemicals --- p.132 / Appendix 4 IR spectrum of a sample --- p.133

Duan Lifang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 83-87). / Abstracts in English and Chinese. / Title Page --- p.i / Abstract (English) --- p.ii / Abstract (Chinese) --- p.iii / Acknowledgements --- p.iv / Table of Contents --- p.v / List of Tables --- p.vii / List of Figures --- p.viii / Symbols and Abbreviations --- p.x / Chapter CHAPTER 1 --- INTRODUCTION / Chapter 1.1 --- Mass spectrometry in biochemistry --- p.1 / Chapter 1.2 --- Electrospray ionization (ESI) --- p.2 / Chapter 1.3 --- Fourier transforms ion cyclotron resonance mass spectrometry (FTICR-MS) --- p.4 / Chapter 1.3.1 --- Ion motions --- p.5 / Chapter 1.3.2 --- Mass calibration --- p.7 / Chapter 1.3.3 --- Tandem mass spectrometry --- p.11 / Chapter 1.4 --- Sustained off-resonance irradiation collision-induced dissociation (SORI-CID) of peptide ions --- p.13 / Chapter 1.5 --- Outline of present work --- p.18 / Chapter CHAPTER 2 --- INSTRUMENTATION AND EXPERIMENTAL / Chapter 2.1 --- Fourier-trans form ion cyclotron resonance mass spectrometer --- p.19 / Chapter 2.1.1 --- Vacuum system --- p.19 / Chapter 2.1.2 --- Nanospray source --- p.23 / Chapter 2.1.3 --- Ion transfer system --- p.26 / Chapter 2.1.4 --- Infinity cell --- p.28 / Chapter 2.1.5 --- Data acquisition system --- p.29 / Chapter 2.2 --- Experimental --- p.29 / Chapter 2.2.1 --- Simple acquisition pulse program --- p.30 / Chapter 2.2.2 --- Tandem mass spectrometry (SORI-CID MS/MS) --- p.32 / Chapter CHAPTER 3 --- DISSOCIATION OF MODEL PEPTIDE IONS UNDER SORI-CID CONDITIONS / Chapter 3.1 --- Introduction --- p.35 / Chapter 3.2 --- Experimental --- p.37 / Chapter 3.3 --- Results and discussion --- p.41 / Chapter 3.3.1 --- "SORI-CID of XG3WG3X (where X 二 R, K and N)" --- p.41 / Chapter 3.3.2 --- SORI-CID of RGnWGnR (where n=l -5) --- p.46 / Chapter 3.3.3 --- SORI-CID of RG3XG3R (where X = D and E) --- p.48 / Chapter 3.4.4 --- SORI-CID of sequence isomers of RG5WG5R --- p.51 / Chapter 3.4 --- Conclusions --- p.56 / Chapter CHAPTER 4 --- EXACT MASS MEASUREMENTS OF THE PRODUCT IONS DERIVED FROM SORI-CID FTICR-MS / Chapter 4.1 --- Introduction --- p.57 / Chapter 4.2 --- Experimental --- p.60 / Chapter 4.3 --- Results and discussion --- p.61 / Chapter 4.3.1 --- Origin(s) of the mass measurement error --- p.63 / Chapter 4.3.2 --- Pressure effect on the cyclotron frequencies of trapped ions --- p.67 / Chapter 4.3.3 --- Modified internal lock-mass calibration method --- p.70 / Chapter 4.4 --- Conclusions --- p.79 / Chapter CHAPTER 5 --- CONCLUSIONS --- p.81 / REFERENCES --- p.83 / APPENDIX I The Proton affinity (PA) and the structural formulae of 20 α-amino acids --- p.88 / APPENDIX II Schematics of the proposed mechanisms of peptide dissociation under low-energy CID conditions --- p.89 / APPENDIX III Pulse programs for simple MS and MS/MS experiments --- p.92 / APPENDIX IV Schematics of the proposed mechanisms for the formation of y8+ ions from the singly protonated arginine- and lysine-containing peptides --- p.99