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https://viurrspace.ca/bitstream/handle/10613/10040/Jan29-1908.pdf?sequence=2

https://viurrspace.ca/bitstream/handle/10613/9324/Aug15-1927.pdf?sequence=2&isAllowed=y

Many software systems contained cloned code, i.e., segments of code that are highly similar to each other, typically because one has been copied from the other, and then possibly modified. In some contexts, clones are of interest because they are targets for refactoring. This paper summarizes the results of a working session in which the problems of merely managing clones that are already known to exist. Six key issues in the space are briefly reviewed, and open questions raised in the working session are listed.

https://viurrspace.ca/bitstream/handle/10613/18481/Jun19-1912.pdf?sequence=2&isAllowed=y

https://viurrspace.ca/bitstream/handle/10613/17623/Jun28-1899.pdf?sequence=2

https://viurrspace.ca/bitstream/handle/10613/19025/Dec26-1874.pdf?sequence=2&isAllowed=y

https://viurrspace.ca/bitstream/handle/10613/21933/Feb27-1878.pdf?sequence=2

This article shows that, contrary to the suggestion of some investment advisers, for an individual Canadian investor subject to personal income taxation, the after-tax yield on a discount bond is always higher than (or, at worst, equal to) the yield on a premium bond. This follows because the tax rate on capital gains is lower than the tax rate on coupon income in Canada. It is also shown that a decline in the capital gains tax rate raises the after-tax yield on discount bonds but reduces the after-tax yield on premium bonds, and may even cause the yield on premium bonds to become negative. Further, a cut in the tax rate on interest income raises the after-tax yield on all bonds, but raises the yield on premium bonds relative to discount bonds. While the lower after-tax yields on highercoupon bonds might be expected to cause the pre-tax yields on these bonds to rise, no evidence of such tax capitalization is found using a large data set of matched pairs of government of Canada bonds for the period 1986-2006. The observed near-equality of pre-tax yields since 1995 for bonds with different coupons implies that individuals in Canada earn a significantly smaller after-tax yield from holding premium bonds than discount bonds.

https://viurrspace.ca/bitstream/handle/10613/17324/Nov16-1898.pdf?sequence=2

This work reports on experiments in which antihydrogen atoms have been produced in cryogenic Penning traps from antiproton and positron plasmas by two different methods and on experiments that have been carried out subsequently in order to investigate the antihydrogen atoms. By the first method antihydrogen atoms have been formed during the process of positron cooling of antiprotons in so called nested Penning traps and detected via a field ionization method. A linear dependence of the number of detected antihydrogen atoms on the number of positrons has been found. A measurement of the state distribution has revealed that the antihydrogen atoms are formed in highly excited states. This suggests along with the high production rate that the antihydrogen atoms are formed by three-body recombination processes and subsequent collisional deexcitations. However current theory cannot yet account for the measured state distribution. Typical radii of the detected antihydrogen atoms lie in the range between 0.4 µm and 0.15 µm. The deepest bound antihydrogen atoms have radii below 0.1 µm. Antihydrogen atoms with that size have chaotic positron orbits so that for the first time antihydrogen atoms have been detected that cannot be described by the GCA-model. The kinetic energy of the weakest bound antihydrogen atoms has been measured to about 200 meV, which corresponds to an antihydrogen velocity of approximately 6200 m/s. A simple model suggests that these atoms are formed from only one deexcitation collision and methods that might lead to a decrease of the antihydrogen velocity are presented. By the second method antihydrogen atoms have been synthesized in charge-exchange processes. Lasers are used to produce a Rydberg cesium beam within the cryogenic Penning trap that collides with trapped positrons so that Rydberg positronium atoms are formed via charge-exchange reactions. Due to their charge neutrality the Rydberg positronium atoms are free to leave the positron trapping region. The Rydberg positronium atoms that collide with nearby stored antiprotons form antihydrogen atoms in charge-exchange reactions. So far, 14 +/- 4 antihydrogen atoms have been detected background-free via a field-ionization method. The antihydrogen atoms produced via the two-step charge-exchange mechanism are expected to have a temperature of 4.2 K, the temperature of the antiprotons from which they are formed. A method is proposed by which the antihydrogen temperature can be determined with an accuracy of better than 1 K from a measurement of the time delay between antihydrogen annihilation events and the laser pulse that initiates the antihydrogen production via the production of Rydberg cesium atoms. First experiments have been carried out during the last days of the 2004 beam time, but the number of detected antihydrogen annihilations has been too low for a determination of the antihydrogen temperature. Trapped antiprotons have been directly exposed to laser light delivered by a Titanium:Sapphire laser in order to investigate if the laser light causes any loss on the trapped antiprotons. Experiments have shown that no extra loss occurs for laser powers of less than 590 mW. This is an important result against the background of the future plan to confine antihydrogen atoms in a combined Penning-Ioffe trap and then to carry out laser spectroscopy on these atoms, since it reveals that laser light does not cause an increase of the pressure in the trapping region to the extend that annihilations with the background gas become noticeable. The ATRAP Collaboration plans to precisely investigate antihydrogen atoms. The ultimate goal is to test the CPT-theorem by a high precision measurement of the 1S-2S transition of antihydrogen and a comparison with the precisely known value of the corresponding transition in hydrogen. This thesis presents the achievement of the first step towards this challenging goal: the production of cold antihydrogen itself.