Grinding operations can be analyzed through monitoring and analysis of the spindle power during the process. Due to the complexity of the process, the analysis on grinding processing signal still heavily relies on personal experience of the engineer instead of having a standard structured method. Therefore, subjectivity and inconsistency is introduced into the analysis procedure. In this thesis, a general method is established to characterize signal, utilize the characterization result to predict the real time condition of grinding wheels and the impact on the process performance measures, and provide suggestions in modification of process parameters to improve the grinding operation. This method is initiated from signal acquisition and conducted based on characterizing the signal and organizing expert knowledge. When the standard procedure to analyze the grinding process through power signal is established, the correlation between input and output can be understood, which can later be utilized for diagnostic applications. During the diagnosis, the real-time grinding wheel status is estimated and the output of the process is predicted. Then, suggestions on modifying the input parameters to address given output issue are generated. Therefore, a signal analysis and knowledge based monitoring and diagnosing system is developed to help enhance the current grinding process planning. This system is realized with a software tool developed with specifically designed algorithms under Matlab environment, upgrading from manual signal processing to an automated characterization procedure and providing process evaluation and improvement suggestions, which will improve the objectivity, consistency and accuracy in the analysis of grinding processes.

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Mon travail de thèse a été entièrement dévoué à l’étude d’une récente technique d’ionisation en spectrométrie de masse : la photoionisation à pression atmosphérique (APPI). Ce travail est développé sur deux axes principaux. D’une part, il vise à appliquer cette méthode d’ionisation à de nouvelles familles de molécules et d’en élargir le cas échéant le domaine d’application. D’autre part et parallèlement à cela, nous nous sommes attachés à l’étude des mécanismes de formation des ions ainsi qu’à l’élucidation des voies de fragmentation. En effet, ces dernières se révèlent souvent intensives et particulières. Les résultats obtenus dans le cadre du premier axe de recherche de ce travail de thèse offrent de nouvelles solutions pour mieux comprendre le comportement de molécules biologiques sous irradiation UV et à pression atmosphérique. En effet, nous avons pu démontrer que la photoionisation à pression atmosphérique pouvait s’étendre à d’autres classes de composés que ceux initialement pressentis et plus particulièrement à des biomolécules polaires et de haut poids moléculaire tels que les acides nucléiques, peptides, les peptides, etc. De plus, ce travail a permis de démontrer l’impact du milieu (solvant) sur le mécanisme de formation des ions sous irradiation UV. Ainsi l’étude et la connaissance des mécanismes fondamentaux de formation des ions en APPI a visé in fine au contrôle de la formation des ions précurseurs et par voie de conséquence, à celui des fragments générés en source. Nous avons observé des ions fragments radicalaires d’un type nouveau, jamais observé auparavant avec les sources d’ions connues L’originalité et le caractère résolument novateur de cette expérience nous ont amené à transférer cette expérience sur une ligne de lumière du Synchrotron SOLEIL. L’utilisation d’une source de lumière accordable en APPI va certainement renforcer la versatilité de cette source d’ions. / My PhD’s work has been completely dedicated to develop new ionization source in mass spectrometry: the atmospheric pressure photoionization (APPI). This work is developed on two main areas. On the one hand, it aims to apply this method to new family of biomolecules. On the other hand, we report a comprehensive study on the ionization mechanisms in APPI. The first part of this manuscript offers a better understanding of the behaviour of the biological molecules under VUV radiation and atmospheric pressure. Indeed, we were able to say that polar and high molecular weight biomolecules could be easily photoionizable. Moreover, this work allows studying the effect of the medium (solvent) on the photoionization mechanism to be studied. It is possible to control the orientation of the observed reactions and to choose a particular type of molecular ion. We observed extensive and peculiar fragmentations which have never been detected with classical ionization techniques. The originality and innovative approach of this experience led us to transfer it to a UV beamline of the Synchrotron SOLEIL. Using an accordable source will certainly enhance the versatility of the ion source.

Thesis. 1976. Ph.D.--Massachusetts Institute of Technology. Dept of Physics. / Microfiche copy available in Archives and Science. / Includes bibliographical references. / Ph.D.

No description available.

The thesis is devoted to non-stationary point process models as generalizations of the standard homogeneous Poisson process. The work can be divided in two parts. In the first part, we introduce a fractional non-homogeneous Poisson process (FNPP) by applying a random time change to the standard Poisson process. We characterize the FNPP by deriving its non-local governing equation. We further compute moments and covariance of the process and discuss the distribution of the arrival times. Moreover, we give both finite-dimensional and functional limit theorems for the FNPP and the corresponding fractional non-homogeneous compound Poisson process. The limit theorems are derived by using martingale methods, regular variation properties and Anscombe's theorem. Eventually, some of the limit results are verified via a Monte-Carlo simulation. In the second part, we analyze statistical point process models for durations between trades recorded in financial high-frequency trading data. We consider parameter settings for models which are non-stationary or very close to non-stationarity which is quite typical for estimated parameter sets of models fitted to financial data. Simulation, parameter estimation and in particular model selection are discussed for the following three models: a non-homogeneous normal compound Poisson process, the exponential autoregressive conditional duration model (ACD) and a Hawkes process model. In a Monte-Carlo simulation, we test the performance of the following information criteria for model selection: Akaike's information criterion, the Bayesian information criterion and the Hannan-Quinn information criterion. We are particularly interested in the relation between the rate of correct model selection and the underlying sample size. Our numerical results show that the model selection for the compound Poisson type model works best for small parameter numbers. Moreover, the results for Hawkes processes confirm the theoretical asymptotic distributions of model selection whereas for the ACD model the model selection exhibits adverse behavior in certain cases.

Dual-task studies have shown higher sensitivity for stimuli presented at the targets of upcoming actions. Generally, movement outcome feedback is also obtained at action targets. This thesis examined whether attention is directed to action targets for the purpose of action selection, as previously concluded, or if attention is directed to monitor feedback about movement outcomes as supported by skilled-action research. Across seven experiments, participants executed either a pointing movement (Experiments 1 – 5) or a saccade (Experiments 6 and 7), while simultaneously identifying a discrimination target ('E' or '3') among distractors (2s and 5s). Action targets were generally cued by a central arrow. Discrimination target identification accuracy measured attention allocation. Crucially, movement accuracy feedback was presented at a spatially separate location from the action target. It was found that during the planning of goal-directed actions, attention is allocated to monitor movement outcomes, even if this information is provided at a spatially separate location from the action target. Attending the separate feedback location resulted in slower reaction times and less accurate pointing. Clear and consistent perceptual enhancement was also demonstrated at the action target location, even when no intrinsic or extrinsic feedback about the action could have been gained from attending there. Specific to saccades, it was found that attention is allocated before saccade execution to both the saccade goal and to the predicted future retinal location of feedback information. Lastly, perceptual performance is greater in general when participants perform the dual-task visually open-loop, that is without visual feedback from the moving hand. These results are novel in showing that attention appears to be required for action target selection, independently of the need to monitor expected locations of feedback.

by Wong Yin Bun, Terence. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 99-104). / Abstract also in Chinese. / List of Figures --- p.ix / List of Tables --- p.xi / Chapter I --- Preliminary --- p.1 / Chapter 1 --- Introduction --- p.2 / Chapter 1.1 --- Thesis themes --- p.4 / Chapter 1.1.1 --- Dynamical view of landscape --- p.4 / Chapter 1.1.2 --- Bottom-up self-feedback algorithm with memory --- p.4 / Chapter 1.1.3 --- Cooperation and competition --- p.5 / Chapter 1.1.4 --- Contributions to genetic algorithms --- p.5 / Chapter 1.2 --- Thesis outline --- p.5 / Chapter 1.3 --- Contribution at a glance --- p.6 / Chapter 1.3.1 --- Problem --- p.6 / Chapter 1.3.2 --- Approach --- p.7 / Chapter 1.3.3 --- Contributions --- p.7 / Chapter 2 --- Background --- p.8 / Chapter 2.1 --- Iterative stochastic searching algorithms --- p.8 / Chapter 2.1.1 --- The algorithm --- p.8 / Chapter 2.1.2 --- Stochasticity --- p.10 / Chapter 2.2 --- Fitness landscapes and its relation to neighborhood --- p.12 / Chapter 2.2.1 --- Direct searching --- p.12 / Chapter 2.2.2 --- Exploration and exploitation --- p.12 / Chapter 2.2.3 --- Fitness landscapes --- p.13 / Chapter 2.2.4 --- Neighborhood --- p.16 / Chapter 2.3 --- Species formation methods --- p.17 / Chapter 2.3.1 --- Crowding methods --- p.17 / Chapter 2.3.2 --- Deterministic crowding --- p.18 / Chapter 2.3.3 --- Sharing method --- p.18 / Chapter 2.3.4 --- Dynamic niching --- p.19 / Chapter 2.4 --- Summary --- p.21 / Chapter II --- Probabilistic Binary Hierarchical Search --- p.22 / Chapter 3 --- The basic algorithm --- p.23 / Chapter 3.1 --- Introduction --- p.23 / Chapter 3.2 --- Search space reduction with binary hierarchy --- p.25 / Chapter 3.3 --- Search space modeling --- p.26 / Chapter 3.4 --- The information processing cycle --- p.29 / Chapter 3.4.1 --- Local searching agents --- p.29 / Chapter 3.4.2 --- Global environment --- p.30 / Chapter 3.4.3 --- Cooperative refinement and feedback --- p.33 / Chapter 3.5 --- Enhancement features --- p.34 / Chapter 3.5.1 --- Fitness scaling --- p.34 / Chapter 3.5.2 --- Elitism --- p.35 / Chapter 3.6 --- Illustration of the algorithm behavior --- p.36 / Chapter 3.6.1 --- Test problem --- p.36 / Chapter 3.6.2 --- Performance study --- p.38 / Chapter 3.6.3 --- Benchmark tests --- p.45 / Chapter 3.7 --- Discussion and analysis --- p.45 / Chapter 3.7.1 --- Hierarchy of partitions --- p.45 / Chapter 3.7.2 --- Availability of global information --- p.47 / Chapter 3.7.3 --- Adaptation --- p.47 / Chapter 3.8 --- Summary --- p.48 / Chapter III --- Cooperation and Competition --- p.50 / Chapter 4 --- High-dimensionality --- p.51 / Chapter 4.1 --- Introduction --- p.51 / Chapter 4.1.1 --- The challenge of high-dimensionality --- p.51 / Chapter 4.1.2 --- Cooperation - A solution to high-dimensionality --- p.52 / Chapter 4.2 --- Probabilistic Cooperative Binary Hierarchical Search --- p.52 / Chapter 4.2.1 --- Decoupling --- p.52 / Chapter 4.2.2 --- Cooperative fitness --- p.53 / Chapter 4.2.3 --- The cooperative model --- p.54 / Chapter 4.3 --- Empirical performance study --- p.56 / Chapter 4.3.1 --- pBHS versus pcBHS --- p.56 / Chapter 4.3.2 --- Scaling behavior of pcBHS --- p.60 / Chapter 4.3.3 --- Benchmark test --- p.62 / Chapter 4.4 --- Summary --- p.63 / Chapter 5 --- Deception --- p.65 / Chapter 5.1 --- Introduction --- p.65 / Chapter 5.1.1 --- The challenge of deceptiveness --- p.65 / Chapter 5.1.2 --- Competition: A solution to deception --- p.67 / Chapter 5.2 --- Probabilistic cooperative-competitive binary hierarchical search --- p.67 / Chapter 5.2.1 --- Overview --- p.68 / Chapter 5.2.2 --- The cooperative-competitive model --- p.68 / Chapter 5.3 --- Empirical performance study --- p.70 / Chapter 5.3.1 --- Goldberg's deceptive function --- p.70 / Chapter 5.3.2 --- "Shekel family - S5, S7, and S10" --- p.73 / Chapter 5.4 --- Summary --- p.74 / Chapter IV --- Finale --- p.78 / Chapter 6 --- A new genetic operator --- p.79 / Chapter 6.1 --- Introduction --- p.79 / Chapter 6.2 --- Variants of the integration --- p.80 / Chapter 6.2.1 --- Fixed-fraction-of-all --- p.83 / Chapter 6.2.2 --- Fixed-fraction-of-best --- p.83 / Chapter 6.2.3 --- Best-from-both --- p.84 / Chapter 6.3 --- Empricial performance study --- p.84 / Chapter 6.4 --- Summary --- p.88 / Chapter 7 --- Conclusion and Future work --- p.89 / Chapter A --- The pBHS Algorithm --- p.91 / Chapter A.1 --- Overview --- p.91 / Chapter A.2 --- Details --- p.91 / Chapter B --- Test problems --- p.96 / Bibliography --- p.99

Vita. / Digitized by Kansas Correctional Industries

acase@tulane.edu / In this thesis, we tackle the statistical problem of demixing a multivariate stochastic process made up of independent, fractional process entries. We consider both Gaussian and non-Gaussian frameworks. The observable, mixed process is then a multivariate fractional stochastic process. In particular, when the components of the unmixed process are self-similar, the mixed process is operator self-similar. Multivariate mixed fractional processes are parameterized by a vector of Hurst parameters and a mixing matrix. We propose a 2-step wavelet-based estimation method to produce estimators of both the demixing matrix and the Hurst parameters. In the first step, an estimator of the demixing matrix is obtained by applying a classical joint diagonalization algorithm to two wavelet variance matrices of the mixed process. In the second step, a univariate-like wavelet regression method is applied to each entry of the demixed process to provide estimators of each individual Hurst parameter. The limiting distribution of the estimators is established for both Gaussian and nonGaussian (Rosenblatt-like) instances. Monte Carlo experiments show that the finite sample estimation performance is very satisfactory. As an application, we model bivariate series of annual tree ring measurements from bristlecone pine trees in White Mountains, California. / 1 / Hui Li