The Precision nEDM Measurement with UltraCold Neutrons at TRIUMF

The TRIUMF Ultra-Cold Advanced Neutron (TUCAN) collaboration aims at a precision neutron electric dipole moment (nEDM) measurement with an uncertainty of $10^{-27}\,e\cdot\mathrm{cm}$, which is an order-of-magnitude better than the current nEDM upper limit and enables us to test Supersymmetry. To achieve this precision, we are developing a new high-intensity ultracold neutron (UCN) source using super-thermal UCN production in superfluid helium (He-II) and a nEDM spectrometer. The current development status of them is reported in this article.Comment: Proceedings of the 24th International Spin Symposium (SPIN 2021), 18-22 October 2021, Matsue, Japa

Cryogenic Systems for the TUCAN EDM Experiment

The TUCAN (TRIUMF UltraCold Advanced Neutron) Collaboration is completing a new ultracold neutron (UCN) source. The UCN source will deliver UCNs to a neutron electric dipole moment (EDM) experiment. The EDM experiment is projected to be capable of an uncertainty of 1 × 10−27 ecm, competitive with other planned projects, and a factor of ten more precise than the present world’s best. The TUCAN source is based on a UCN production volume of superfluid helium (He-II), held at 1 K, and coupled to a proton-driven spallation target. The production rate in the source is expected to be in excess of 107 UCN/s; since UCN losses can be small in superfluid helium, this should allow us to build up a large number of UCNs. The spallation-driven superfluid helium technology is the principal aspect making the TUCAN project unique. The superfluid production volume was recently cooled, for the first time, and successfully filled with superfluid helium. The design principles of the UCN source are described, along with some of the challenging cryogenic milestones that were recently passed

Applications of Automated Scanning X-ray Spectroscopy for Future APXS Instruments

The objective of this project was to develop a prototype of an automated positioning system for future APXS instruments. The current instruments on Mars rely solely upon the rover arm to place them against rocks or soils, making consecutive measurements with small offsets challenging and resource intensive to conduct. The prototype consists of an x-ray detector and an x-ray tube mounted to a computer controlled three-axis positioning system. Passive surface scans were completed over 55Fe and 244Cm sources to determine raster parameters and to characterize the detector field of view. Active XRF scans of a sample tray containing geological specimens, as well as heterogeneous natural rocks, were acquired to evaluate the system under a variety of field conditions. The results demonstrate that a microcontroller, similar to that used by the APXS for signal processing, is capable of automated scanning and rudimentary decision making based on short duration spectra. This involved using the elemental distribution within the scan field to automatically position the instrument to the region of greatest scientific interest in the xy plane, and adjusting the detector stand-off for optimal data acquisition. The achievable spatial resolution was sufficient to distinguish regions of distinct elemental composition as small as 5 mm, although smaller dimensions are possible. While several aspects of the system must be developed further in order to accommodate more complex sample geometries and enable more advanced decision making, the results clearly demonstrate the potential of such a system to significantly improve the scientific return of future instruments

Modelling patient decision-making among Manitobans in the context of type II diabetes mellitus (T2DM)

This thesis documents the development and implementation of a dynamic, stochastic model of decision-making in the context of type 2 diabetes mellitus (T2DM), with specific reference to the Province of Manitoba. The second chapter (i.e., after the introduction) informs development of the model by summarizing the state of knowledge regarding T2DM and surveying existing economic models and frameworks. T2DM is a chronic condition that can reduce life expectancy, adversely affect labour market performance, and profoundly impact quality of life. People can reduce their risk of T2DM and manage its progression in various ways but exert limited control over health outcomes. Within this context, this thesis studies optimal decision-making by fully-rational, forward-looking individuals by extending Peter Zweifel, Friedrich Breyer, and Mathias Kifmann’s model of health production and demand. The third chapter conceptualizes health-related decision-making as a dynamic optimization problem in which health and economic events constitute transitions between predefined states. T2DM and its complications detract from quality of life, increase mortality risk, and restrict opportunities to engage in consumption and leisure. People can reduce, but not eliminate, the chance of developing T2DM and the rate of diabetic progression through regular physical activity and adherence to healthy eating habits and pharmacotherapy, but only by sacrificing time and income that could be allocated to other things. The model cannot be solved analytically but is amenable to application of numerical techniques. The remainder of Chapter 3 selects values or ranges for model parameters to reflect the circumstances in which Manitobans make health-related decisions. The fourth chapter describes model implementation, interprets key results, and illustrates potential applications. Fully-rational, forward-looking individuals are generally motivated to invest in health, but this is mediated by their circumstances and personal characteristics, and they may sometimes trade off increased risk of adverse health outcomes or accelerated rate of diabetic progression in return for more consumption or leisure. Microsimulations based on these results suggest opportunities to reduce efficiency losses attributable to T2DM in Manitoba through improved health-related decision-making, but this requires investing in both T2DM prevention and management, and may entail altering the structure of incentives within which choices are made.February 202

Dynamic Models of Vibrating Rotor Stages

Fan and compressor stages of turbofan aircraft engines are subjected to dynamic excitations. Often these excitations are at frequencies equal to or multiples of the rotor speed. This form of dynamic stimulus is called per-revolution excitation or integral-order excitation. When the natural resonant frequency of a fan stage coincides with the frequency of the source, severe vibration usually results. For shrouded fan stages the natural frequency is that of a coupled dynamic system consisting of disk, blades, and shroud. A modeling technique is developed to study the vibration. Small scale models are cast of flexible silicone rubber, known as RTV. The rubber models rotate and are excited by air nozzles located at discrete circumferential positions. Visual observation of the standing-wave oscillation clearly shows the familiar relations of forced vibrations such as magnification factor, phase shift, and the effects of damping. RTV silicone rubber is easily cast into complex shapes. This allows rapid evaluation of the many resonant-response blade-disk shroud configurations including unsymmetrical designs that may be difficult to analyze with current computing techniques.</jats:p

Underrepresentation of Minorities in Gifted and Talented Programs: A Content Analysis of Five District Program Plans

Many educators and researchers recognize the issue of underrepresented minority groups in gifted and talented education programs. Since the landmark Supreme Court case Brown vs Board of Education in 1954, policies, laws, and standards have been attempting to establish equity in educational programs. This content analysis explores how select districts in the metropolitan region of Colorado align with the NAGC’s standard 2. The research showed that the majority of these districts followed NAGC’s standard 2, but the underrepresentation of minority groups within the metropolitan region of Colorado continued. National, state, and local districts need to do more to promote equity and diversity