Endurance testing of downstream cathodes on a low-power MPD thruster

A low-power MPD thruster with downstream cathode was tested for endurance with a series of hollow cathode designs. Failure modes and failure mechanisms were identified. A new hollow cathode (with rod inserts) has emerged which shows promise for long life. The downstream positioning of the cathode was also changed from an on-axis location to an off-axis location. Data are presented for a 1332-hour life test of this new hollow cathode located at the new off-axis location. Xenon propellant was used

Chunking by the rat in the radial-arm maze.

Dept. of Psychology. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1989 .B986. Source: Masters Abstracts International, Volume: 40-07, page: . Thesis (M.A.)--University of Windsor (Canada), 1989

Canada–US Border Communities: What the People Have to Say

This paper investigates the Canada-U.S. borderlands relationship along the two geographic corridors as bounded by Lake Superior: Sault Ste. Marie, Ontario–Sault Ste. Marie, Michigan and Thunder Bay, Ontario–Duluth, Minnesota. Borderland communities—driven by their shared cultural characteristics (ethnicity, language, religion)—are said to challenge the border as a dividing device and undermine the very essence of international borders. Moreover, borderlands regions are dynamic and overlapping, providing the first point of contact and interaction between nations. We use interviews of over 200 people living in these borderlands regions to investigate the cross-border relationships of Canada-U.S. border communities. We find that despite the challenges of crossing the border, these communities retain a strong sense of shared values

Differences That Matter: Canada, the United States and Environmental Policymaking

Does the way Canada, as a nation state, approach international environmental policymaking make a difference with respect to solving environmental problems in the Americas? We argue that it does, and it is a difference that matters. Canadian efforts toward multilateralism and toward inclusiveness (e.g., willingness to work with weaker nations) serve as a counter balance to the growing unilateralism and ever present exceptionalism of the United States, currently the most powerful country in the world, and Canada’s southern neighbor and regional partner in developing environmental policy that affects the northern Americas directly and all of the Americas indirectly. Our argument is made first generally, and then specifically using involvement and reaction to the goals set out by the Commission for Environmental Cooperation (CEC), where, along with Mexico, Canada and the United States play leading roles. The basic contention of this paper is that the vision for and goals of the CEC are much more aligned with the way Canada perceives the way international environmental policymaking should be implemented, and that by fostering that vision, Canada tries to counter the tendency of the present-day United States administration to go at it alone, and thereby provides a linkage to other countries in the Americas to position themselves for participation in regional environmental policymaking

Bridges and Barriers: The Lake Superior Borderlands

This paper investigates the Canada–US borderlands relationship along the two geographic corridors as bounded by Lake Superior: Sault Ste. Marie, Ontario–Sault Ste. Marie, Michigan and Thunder Bay, Ontario–Duluth, Minnesota. Borderland communities—driven by their shared cultural characteristics (ethnicity, language,religion)—are said to challenge the border as a dividing device and undermine the very essence of international borders. Moreover, borderlands regions are dynamic and overlapping, providing the first point of contact and interaction between nations. Our results depict inherent differences between these particular border regions, with each illustrating characteristics that both connect and divide. Despite the passage of time and both countries’ determined efforts to make the passage safe and less demanding, the peoples in these border regions perceive a continuing frustration with crossing the border and connecting to the people on the other side of the border

Extraction efficiency of a pulse column of varied geometry

An investigation was made of the effects of plate spacing, hole diameter, percent free plate area, pulse amplitude, and pulse frequency on the extraction efficiency of a 1-in. diameter pulse column. The hexone-acetic acid-water system was used. Two levels of each factor were incorporated in an experimental design based on statistical methods. \u27The data were analyzed by the analysis of variance technique

Normal-metal quasiparticle traps for superconducting qubits

The presence of quasiparticles in superconducting qubits emerges as an intrinsic constraint on their coherence. While it is difficult to prevent the generation of quasiparticles, keeping them away from active elements of the qubit provides a viable way of improving the device performance. Here we develop theoretically and validate experimentally a model for the effect of a single small trap on the dynamics of the excess quasiparticles injected in a transmon-type qubit. The model allows one to evaluate the time it takes to evacuate the injected quasiparticles from the transmon as a function of trap parameters. With the increase of the trap size, this time decreases monotonically, saturating at the level determined by the quasiparticles diffusion constant and the qubit geometry. We determine the characteristic trap size needed for the relaxation time to approach that saturation value.Comment: 11 pages, 5 figure