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No description available.

No description available.

No description available.

No description available.

No description available.

Since high-mass stars form deeply embedded within dense molecular clumps, the evolution of young stars and of dense clumps is inextricably linked. Previous datasets, however, lack the information necessary to test the prevailing theories. Definitive tests require a sufficiently large sample of molecular clumps and maps of their gas temperatures, column densities, velocity dispersions, and velocities at a spatial resolution comparable to, or smaller than, the clump scale (~1 pc). The Radio Ammonia Mid-Plane Survey (RAMPS), a new molecular line survey of thermal NH3 and H2O masers, provides the necessary data. In this dissertation, I used RAMPS data and archival datasets to test several theories of high-mass star formation and to investigate the co-evolution of molecular clumps and high-mass stars. All theories of high-mass star formation make testable predictions regarding clump kinematics and gravitational stability. Analyses of RAMPS kinematic data revealed that the majority of molecular clumps, particularly those in early evolutionary stages, are unstable to gravitational collapse. Further, they display infall motions, a key prediction of the theory of competitive accretion. I also investigated the kinematics of molecular filaments by comparing their measured velocity gradients to those predicted by hydrodynamical simulations. The measured spatial distributions of velocity gradients are inconsistent with existing models. Feedback from protostars and stars is predicted to alter the properties of surrounding clumps. I investigated feedback size scales and found that high-mass protostellar and stellar feedback significantly changes the temperatures, chemical abundances, and velocity dispersions of clumps on scales of ~0.3 to 3 pc. Finally, I observed a massive molecular cloud filament undergoing an interaction with a supernova shock, which is accelerating, heating, and injecting turbulence into the filament's gas. Although the molecular cores hosted by the filament may remain gravitationally bound, the filament is gravitationally unbound and likely being dispersed. Given that the shock is removing a reservoir of gas that could have been accreted by the cores, these data suggest that the supernova is inhibiting star formation.

<p>The nuclear safety industry makes extensive use of thermalhydraulics system analysis and computational fluid dynamics codes for validation and predictive purposes. These codes take different approaches to provide the user with reasonable estimates of system and component behaviors. With each displaying its own strengths, it is only logical to pursue coupled systems of these codes to create increasingly accurate, versatile, and more computationally efficient safety analysis tools. This work presents results of the attempted coupling of CD-ADAPCO's STAR-CCM+, a computational fluid dynamics (CFD) code, to Atomic Energy of Canada's CATHENA thermalhydraulics (TH) code. This coupled system is used in the simulation of the conditions within an inlet header of the RD-14M experimental facility under single phase conditions in the initial phase of selected test. This inlet header is removed from a modified CATHENA test B9401 deck and instead modelled in STAR-CCM+. Custom applications were written to allow information exchange at the newly created boundaries to provide an attempt at a coupled system. Results are provided through multiple stages of development of the coupled system, from the unmodified B9401 test case of CATHENA into a coupled system with header behavior predicted by STAR-CCM+. Though successful information transfer between codes was established at each desired time step and interval, the current technique was found to be insufficient for establishing acceptable steady-state conditions for the commencement of more complex (transient and two-phase) conditions.</p> / Master of Applied Science (MASc)

The research and development effort for the next generation of nuclear power stations is being coordinated by the Generation IV International Forum (GIF). The supercritical water reactor (SCWR) is one of the six reactor technologies currently being pursued by the GIF. The unique nature of supercritical water necessitates further examination of its heat transfer regimes. The GIF SCWR blind computational benchmark exercise is focused on furthering the understanding of the heat transfer to supercritical water as well as its prediction. A methodology for computational fluid dynamics (CFD) simulations using STAR-CCM+ 9.02.005 has been developed for submission to the GIF SCWR computational benchmark exercise. The experiments of the GIF SCWR computational benchmark exercise were those conducted by the Japan Atomic Energy Agency (JAEA). They are of supercritical water flowing upward in a 7 rod bundle. Of the three experimental cases there are (i) an isothermal case, (ii) a low enthalpy, low heat flux case and (iii) a high enthalpy, high heat flux case. A separate effects study has been undertaken and the SST turbulence model has been chosen to model each of the three experiments. A near wall treatment that ensures a y+<0.09 has been used for both of the heated cases and a near wall treatment that ensures a y+<0.53 has been used for the isothermal case. This computational approach was determined to be the optimal choice which balances solution accuracy with computation time. Final simulation results are presented in advance of the release of the experimental results in June 2014. / Thesis / Master of Applied Science (MASc)

This study explored the relationship between general or real-world multitasking and task specific multitasking as related to the real time strategy game Star Craft II: Wings of Liberty (Blizzard, 2010). In addition to exploring this relationship, the research also attempted to examine the effect task specific multitasking training had within Star Craft II. Data for the current research were collected in two phases. Phase one consisted of a pre/post-test design, with random assignment to either the gamer-control or experimental group. Participants in the experimental group were asked to complete 10 to 11 hours on the Star Craft II based Multitasking Trainer (stet_tcl, 2010) in between two, five trial blocks of the SynWin (Acivity Research Services, 2000); a computer based general multitasking measure. Participants in the gamer-control group were asked to complete 10 to 11 hours of one-versus-one Star Craft II ladder matches, and complete the same pre/post-test SynWin battery. Both groups were asked to send the researcher their three most recent one-versus-one ladder matches prior to starting the assigned protocol, and three more upon completion. Phase two participants only completed the pre-test SynWin battery, and were assigned to either the non-gamer control or gaming-control groups based on their weekly use of PC/console games and Star Craft II play. Inclusion in the non-gamer control group required less than one hour of PC/console gaming per week. Participants in the gaming-control group were asked to submit their three most recent one-versus-one Star Craft II ladder replays. For the purpose of this research, the operational definition for Star Craft II multitasking was effective actions per-minute (EAPM), a subset of actions per-minute (APM). Analysis of the gathered data from both phases of recruitment indicated a moderately strong positive relationship between SynWin scores and EAPM values (r = 0.636, p = 0.014). An evaluation of the effectiveness of the multitasking trainer was not completed due to a lack of adequate participation. / Kinesiology