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This thesis contains 13 blueprints that are not available in the digital version. The blueprints are very large and would require too much time to digitize. Please contact eScholarship@mcgill.ca to request more information.

Thèse ou mémoire avec insertion d'articles / L'objectif de ce travail de recherche est le développement de planifications de trajectoires analytiques de type point à point pour mécanismes à câbles suspendus complètement actionnés. Spécifiquement, cette thèse propose une planification de trajectoire point à point dite de transition pour mécanismes à effecteur ponctuel à 2 et à 3 degrés de liberté (ddl), ainsi que des planifications de trajectoires point à point classiques pour mécanismes spatiaux à 3 ddl, d'une part, et pour mécanismes à 6 ddl de type Gough-Stewart, d'autre part. Chaque trajectoire développée assure aux points limites une vitesse nulle et une accélération continue, en plus d'être spécifiquement construite dans le but de maintenir des forces exclusivement de tension dans les câbles tout au long du tracé. La trajectoire de transition pour mécanismes à effecteur ponctuel à 2 ddl et à 3 ddl relie une pose à l'équilibre statique du mécanisme à une pose à accélération non-nulle et consiste en des oscillations rectilignes d'amplitude progressivement croissante centrées à la pose au repos. Il est établi que cette trajectoire est réalisable avec des forces exclusivement de tension dans les câbles pourvu qu'elle demeure entièrement sous le plan formé par les enrouleurs, ce qui en démontre la pertinence. La trajectoire point à point destinée au mécanisme spatial à 3 ddl joint deux positions quelconques de l'espace tridimensionnel en suivant un tracé hypocycloïdal. Pour illustrer la pertinence de cette construction, il est démontré qu'il suffit que l'enveloppe circulaire de l'hypocycloïde soit entièrement située sous le plan des enrouleurs pour que la trajectoire souhaitée soit réalisable avec des forces exclusivement de tension dans les câbles. Enfin, la trajectoire à 6 ddl destinée au mécanisme hexapodal relie deux poses arbitraires. Elle consiste, pour sa composante translationnelle, en une version améliorée de la trajectoire hypocycloïdale définie pour le mécanisme à 3 ddl, tandis que sa composante rotationnelle consiste en des oscillations angulaires le long des arcs de l'hypocycloïde. La pertinence de cette formulation est démontrée par le calcul, pour certaines positions génériques de la plate-forme, de la proportion d'orientations que la trajectoire est en mesure de joindre avec un mouvement horizontal partant d'une pose au repos : il est obtenu que, pour des valeurs typiques, la planification proposée parvient à atteindre environ 90% de l'espace atteignable en orientation du mécanisme. / The purpose of this work consists in the development of analytical point-to-point trajectory procedures for fully-actuated cable-suspended parallel mechanisms. Specifically, this thesis proposes a static-to-dynamic transition trajectory formulation for 2-degree-of-freedom (dof) and 3-dof mechanisms with point-mass end-effectors, as well as point-to-point trajectory formulations for spatial 3-dof and 6-dof mechanisms. Each proposed trajectory ensures a zero instantaneous velocity at the endpoints and the continuity of the acceleration, and is specifically designed to maintain tensile-only forces in the cables throughout the motion. The proposed static-to-dynamic transition trajectory for the planar and spatial point-mass mechanisms connects a pose at rest in the static workspace to an arbitrary pose with a non-zero acceleration and consists of rectilinear oscillations of progressively increasing amplitude centred at the pose at rest. It is shown that this trajectory is dynamically feasible with tensile-only forces in the cables as long as it remains entirely below the plane passing by the fixed cable spools, which justifies its relevance. The point-to-point trajectory intended for spatial 3-dof mechanisms connects two arbitrary positions in three-dimensional space by following a hypocycloidal path. In order to demonstrate the relevance of the proposed formulation, it is shown that it suffices that the circular envelope of the hypocycloid remains entirely below the plane passing by the cable spools for the desired motion to be feasible with tensile-only forces in the cables. Finally, the 6-dof point-to-point trajectory intended for hexapodal mechanisms connects two poses with arbitrary position and orientation. It consists, for its translational component, in an enhanced version of the hypocycloidal trajectory defined for the 3-dof mechanism, while its rotational component consists of rotational oscillations along the arcs of the hypocycloid. The relevance of this construction is demonstrated by the computation, for generic positions of the platform, of the proportion of orientations that the trajectory can reach through a horizontal motion starting from a pose at rest: it is obtained that, for typical values, the proposed formulation can reach approximately 90% of the orientational workspace of the mechanism.

No / A comprehensive study into the performance of 4 injection molding machines is reported, using identical mold, polymer, and processing conditions. Start-up dynamics and process repeatability were directly compared across machine technologies. One servohydraulic, one proportional hydraulic and two servoelectric machines were used in the study, ranging in age from 14 years to 1 year old at the time of the study. Experiments were carried out at identical set molding conditions for a run of 400 parts and part quality and process parameters monitored. Results showed a significant start up period in each case, correlating strongly to mold temperature. Age of machine proved to be the most significant factor in determining process repeatability; modern machines having significantly lower variation than older ones. Differences between the operating characteristics of hydraulic and electric machines were detected, control of screw position in hydraulic machines being less repeatable, although this had a minor effect on part repeatability. Electric machines were found to use up to 4 times less energy than their hydraulic counterparts and operate more efficiently.

On multiline slot machine games, small “wins” often amount to less than the spin wager, resulting in a monetary loss to the gambler. Nevertheless, these monetary losses are still accompanied by “winning” (and potentially reinforcing) audio-visual feedback. Dixon, Harrigan, Sandhu, Collins, and Fugelsang (2010) termed these potentially reinforcing losses as losses disguised as wins, or LDWs. Dixon et al. previously showed that novice gamblers appear to somatically miscategorize LDWs as wins rather than correctly categorizing these outcomes as losses. Two studies are presented which investigated whether novice gamblers would psychologically miscategorize LDWs as wins as well. In both studies, we investigated participants’ categorizations of LDWs using two measures. First, we asked participants to recall how many times they had won during a playing session and predicted that if participants miscategorize LDWs as wins, then they should conflate LDWs and wins in memory. In Study 1, participants played 200 spins on a real slot machine game with either relatively fewer or relatively many expected LDWs. We found that participants who experienced more LDWs during the playing session recalled winning significantly more often than participants who experienced fewer LDWs, despite how many actual wins the participant experienced, or how much they won or lost overall. In Study 2, we found that participants recalled winning significantly more often in simulator games with more rather than fewer LDWs, despite identical numbers of real wins and identical payback percentages in both games. We referred to this type of memory error as the LDW overestimation effect. The second measure we used to investigate participants’ categorizations of LDWs was more immediate and direct. We evaluated whether participants would miscategorize LDWs as wins or correctly categorize these outcomes as losses by simply asking them to verbally label slot machine spin outcomes. In both studies, we found that the majority of participants miscategorized LDWs as wins rather than correctly categorizing the outcomes as losses. Implications for problem gambling are discussed.

This thesis is divided into two parts. In the first part, a general problem of the robust template decomposition with restricted weights for cellular neural networks (CNNs) implementing an arbitrary Boolean function is investigated. In the second part, some primary study of the novel Wilcoxon learning machines is made. In the first part of the thesis for the robust CNN template design, the geometric margin of a linear classifier with respect to a training data set, a notion borrowed from the machine learning theory, is used to define the robustness of an uncoupled CNN implementing a linearly separable Boolean function. Consequently, the so-called maximal margin classifiers can be devised via support vector machines (SVMs) to provide the most robust template design for uncoupled CNNs implementing linearly separable Boolean functions. Some general properties of robust CNNs with or without restricted weights are discussed. Moreover, all robust CNNs with restricted weights are characterized. For an arbitrarily given Boolean function, we propose an algorithm, which is the generalized version of the well known CFC algorithm, to find a sequence of robust uncoupled CNNs implementing the given Boolean function. In the second part of the thesis, we investigate the novel Wilcoxon learning machines (WLMs). The invention of these learning machines was motivated by the Wilcoxon approach to linear regression problems in statistics. The resulting linear regressors are quits robust against outliers, as is well known in statistics. The Wilcoxon learning machines investigated in this thesis include Wilcoxon Neural Network (WNN), Wilcoxon Generalized Radial Basis Function Network (WGRBFN), Wilcoxon Fuzzy Neural Network (WFNN), and Kernel-based Wilcoxon Regressor (KWR).

Thèse doctorat : Génie Electrique : Villeurbanne, INSA : 2003. / Thèse rédigée en espagnol. En fin de thèse, résumé succint des chapitres en français. Titre provenant de l'écran-titre. Bibliogr. p. 243-247.

Thesis (M.S.)--Brigham Young University. Dept. of Mechanical Engineering, 2004. / Includes bibliographical references (p. 87-89).

On multiline slot machine games, small “wins” often amount to less than the spin wager, resulting in a monetary loss to the gambler. Nevertheless, these monetary losses are still accompanied by “winning” (and potentially reinforcing) audio-visual feedback. Dixon, Harrigan, Sandhu, Collins, and Fugelsang (2010) termed these potentially reinforcing losses as losses disguised as wins, or LDWs. Dixon et al. previously showed that novice gamblers appear to somatically miscategorize LDWs as wins rather than correctly categorizing these outcomes as losses. Two studies are presented which investigated whether novice gamblers would psychologically miscategorize LDWs as wins as well. In both studies, we investigated participants’ categorizations of LDWs using two measures. First, we asked participants to recall how many times they had won during a playing session and predicted that if participants miscategorize LDWs as wins, then they should conflate LDWs and wins in memory. In Study 1, participants played 200 spins on a real slot machine game with either relatively fewer or relatively many expected LDWs. We found that participants who experienced more LDWs during the playing session recalled winning significantly more often than participants who experienced fewer LDWs, despite how many actual wins the participant experienced, or how much they won or lost overall. In Study 2, we found that participants recalled winning significantly more often in simulator games with more rather than fewer LDWs, despite identical numbers of real wins and identical payback percentages in both games. We referred to this type of memory error as the LDW overestimation effect. The second measure we used to investigate participants’ categorizations of LDWs was more immediate and direct. We evaluated whether participants would miscategorize LDWs as wins or correctly categorize these outcomes as losses by simply asking them to verbally label slot machine spin outcomes. In both studies, we found that the majority of participants miscategorized LDWs as wins rather than correctly categorizing the outcomes as losses. Implications for problem gambling are discussed.

Thesis (M.S.)--Ohio University, June, 1996. / Title from PDF t.p.