The Coordinate Measuring Machine (CMM) is a key improving the reliability and quality of production. During operation, however, collision between the CMM, probe system, and parts may result in costly damage. Avoiding potential collisions is always an important issue for CMM inspection. This thesis reports design and implementation of an online collision detection system for CMMs. Compared to previous offline collision detection implementations, the new online collision detection system can react to potential collision situations in real time. The collision avoidance system architecture and algorithms are described in this thesis. Each possible CMM translation and probe rotation case is considered. Every component in this system is connected by certain communication protocol and distributed on different computers according to the requirements of applications. This design brings more flexibility to this system. The system components for inspection path planning, collision detection, and CMM motion control are distributed to separate computers, with a TCP/IP based protocol used for communication. This modular, component based design provides more flexibility. / Thesis / Master of Applied Science (MASc)

This study was conducted to investigate and model the high traffic collision frequencies in the City of Edmonton, Canada. Consistent collision spikes were observed on Fridays compared to the other days of the week. The first Negative Binomial model was formulated to establish a relation between the collision frequency and the independent variables. The second Multinomial logistic regression model was formulated to examine the probability of age categories and gender involved in collision for each day of week considering collision has happened. The proposed collision prediction models were found good. They could provide a realistic estimate of expected collision frequency and properties of collision for a particular day as a function of number of hours of daylight, number of hours of snowfall, visibility, age and gender. It is hoped that predicted collision frequency will help the decision maker to quantify traffic safety of Edmonton and improve the scenario. / Transportation Engineering

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Att kollidera är en av riskerna som föreligger då ett fartyg framförs till sjöss trots att det finns internationella regelverk, så som Sjövägsreglerna, enbart utformade för att förhindra detta. I denna kvantitativa litteraturstudie har det undersökts vilka avvikelser från Sjövägsreglerna som bidragit till kollision samt hur regelavvikelserna skiljer sig utifrån fartygstyp, tid på dygnet, sikt och bryggbemanning. Haverirapporter utarbetade från två haverikommissioner har undersökts och utifrån haverikommissionernas egna slutsatser om orsak till kollision har författarna sedan identifierat vilka Sjövägsregler fartygen avvikit från vid kollisionen. Två haverikommissioner valdes för att kunna jämföra om det finns skillnader i resultatet i deras utredningar. I en majoritet av kollisionerna hade fartygen avvikit från någon eller några av Sjövägsreglerna. De regler flest fartyg avvek från och som bidrog till kollision var de regler som behandlar utkik och bedömning av risk för kollision. Undersökningen visar att ombord på fartyg bör vakthavande styrman alltid ha en utkik på bryggan och dessutom nyttja denna på rätt sätt. När det gäller risk för kollision bör styrman använda radar på rätt sätt samt känna sin utrustning och dess begränsningar väl. / Collision is one of the risks that exist for vessels traveling the seas despite the fact that there are international regulations, such as the Collision Regulations, put in place to prevent such occurrences. Through a literature study we have used the collision reports from two maritime investigation bureaus to identify which deviations from the Collision Regulations that contribute to collisions and how the deviations differ between different vessels, time of day, state of visibility and staffing on the bridge. When identifying which deviations from regulations that contributed to the collision we have used the investigation bureaus own conclusions as base. We picked two different bureaus so that we would be able to compare the results and see if there is a difference. In a majority of the collisions the colliding vessels had deviated from one or more of the Collision Regulations. The regulations that most vessels deviated from in situations that led to collisions were the regulations concerning lookout and assessment of the risk of collision. Our study show that onboard vessels the watch keeping officer should always have a lookout on the bridge and use this resource correctly. Concerning the assessment of risk of collision it is important that the watch keeping officer use his radar equipment correctly and know its limitations.

La Spectrométrie de Masse par Plasma à Couplage Inductif (ICP-MS) s’est imposée comme technique d’analyse inorganique, de par sa souplesse d’utilisation, sa sensibilité et sa reproductibilité. L’analyse élémentaire et isotopique des combustibles nucléaires irradiés et de cibles de transmutation, doit faire face à un spectre de masse riche, dû à la présence de nombreux radionucléides. La technique ICP-MS ne peut toutefois pas différencier les ions de même masse ce qui induit des interférences isobariques et poly-atomiques quand les ions de même masse sont des espèces chimiques différentes. La majorité des ICP-MS de nouvelles générations sont équipés d’un dispositif de cellule de collision-réaction permettant la résolution in situ de telles interférences. Ce dispositif est un multipôle (quadripôle, hexapôle ou octopôle) rempli de gaz dont les molécules percutent les ions formés dans le plasma puis éventuellement réagissent. La résolution des interférences est alors basée sur la différence de réactivité chimique qui peut exister entre l’ion d’intérêt et son interférant, vis-à-vis d’un gaz de réaction donné : le choix du gaz est essentiel. Une meilleure compréhension des réactions « ions – gaz » pourrait ainsi aider à choisir le gaz réactif. Trois ICP-MS, avec différentes géométries de cellule de collision-réaction, ont été utilisés pour cette étude : Perkin Elmer Elan DRC e (quadripôle), Thermo Fischer X serie II (hexapôle) et Agilent Technologies 7700x (octopôle). L’influence de la géométrie de la cellule sur différents paramètres expérimentaux et sur la résolution de l’interférence poly-atomique 56Fe+/40Ar16O+ a été déterminée afin de mesurer le fer à l’état de trace ou d’ultra-trace. Cette étude préliminaire a ensuite été appliquée pour mesurer le fer en tant qu’impureté dans l’oxyde d’uranium, puis valider la méthode à l’aide d’un matériau de référence. La réactivité de métaux de transition (Zr, Ru, Pd, Ag, Cd, Sn), de lanthanides (La, Ce, Nd, Sm, Eu, Gd, Dy, Er et Yb) et d’actinides (U, Np, Pu, Am et Cm), éléments d’intérêts dans le domaine du nucléaire, a été testée vis-à-vis de nombreux gaz (O2, CO, CO2, N2O, NO, CH4, C2H4, C3H8, NH3, CH3Cl et COS). Parmi ces gaz, l’ammoniac est un gaz sélectif de lanthanides entre eux et aussi d'actinides. L’étude théorique, menée par des calculs DFT (Théorie de la Fonctionnelle de la Densité) et ab initio (MP2 et CCSD(T)) a permis de reproduire la différence de réactivité de quatre cations lanthanide (La+, Sm+, Eu+ et Gd+). Les chemins de réactions, les profils d’énergie potentielle, les orbitales moléculaires et l’influence de la configuration électronique le long du chemin de réaction ont permis de proposer une explication de la différence de réactivité observée. Quelques résultats expérimentaux et calculs de chimie quantique indiquent comment étendre ces explications aux actinides. / Inductively Coupled Plasma Mass Spectrometry (ICP-MS) emerged as the most essential technique in inorganic analytical chemistry thanks to its numerous assets, particularly its flexibility, its sensitivity and its reproducibility. As part of the elementary and isotopic analysis of irradiated fuel and transmutation target, the analyst is faced with a complex mass spectrum, due to the presence of many radionuclides. ICP-MS can not differentiate ions with the same mass, which induces isobaric and polyatomic interferences when the ions at the same mass are different chemical species. Last generations of ICP-MS have introduced collision reaction cells. It can in situ reduce these isobaric or polyatomic interferences. The cell is a multipol (quadrupole, hexapole or octopole) device filled with a collision and/or reaction gas. The gas molecules collide or possibly react with the ion beam, which eliminates or reduces interferences. Such resolution of interferences is based on the difference of chemical behaviours between the analyte and the interfering species: the choice of the gas is crucial. A better understanding of the “ion – gaz” reaction should help choosing the reacting gases. Three ICP-MS, with the different cell geometries, were used for this study: Perkin Elmer Elan DRC e (quadrupole), Thermo Fischer X serie II (hexapole) and Agilent Technologies 7700x (octopole). The effects of the cell geometry on different experimental parameters and on the resolution of the 56Fe+/40Ar16O+ polyatomic interferences were examined to measure iron at trace or ultra-trace level. This preliminary study was applied to measure iron as impurities in uranium oxide, the method was then validated with a Certified Reference Material. The reactivities of transition metals (Zr, Ru, Pd, Ag, Cd, Sn), lanthanides (La, Ce, Nd, Sm, Eu, Gd, Dy, Er and Yb) and actinides (U, Np, Pu, Am and Cm), elements of interest in the nuclear field, are studied with numerous gases (O2, CO, CO2, N2O, NO, CH4, C2H4, C3H8, NH3, CH3Cl and COS). Among these gases, ammonia appears to be a selective gas for lanthanides and actinides. DFT (Density Functional Theory) and ab initio calculations (MP2 and CCSD(T)) were able to reproduce the reactivity differences among lanthanide cations (La+, Sm+, Eu+ and Gd+). Reaction paths, potential energy surfaces, molecular orbitals and the influence of the electronic configuration along the reaction path are used to propose an explanation for the observed differences in the chemical behaviours. A few experimental results and quantum calculations indicate how to extend these explanations to actinides.

Master of Science / Department of Physics / Itzhak Ben-Itzhak / Collisions between simple diatomic molecular ions and target atoms have previously been limited to studying a subset of reaction channels for a given experiment, or, for cases where all reaction channels involved were measured, only the cross sections have been reported in literature. Experimentalists are faced with the challenge of improving their techniques for studying these collisions in order to gain further physical insight into the processes which occur. Our group has made progress in studying the molecular dissociation channels from the collisions via a coincidence three-dimensional momentum imaging technique. This technique allows us to measure all reaction channels involved simultaneously, while separating the channels from each other. By re-design of the experimental apparatus, i.e. changing the target from a gas cell to an open geometry jet, we have gained the ability to measure recoil ions produced in the collision in addition to the molecular fragments. Furthermore, we can also study collisions where the molecular projectile does not dissociate as long as it scatters to large angles. Results from the collision cell setup will be shown and discussed as well as first results from the jet setup. This work is a contribution to a larger project, and the emphasis for this stage will be placed on the development of the experimental technique as well as improvements for the future of the project.

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