Induced attack was studied under three conditions: (1) paired experimentally naive rats were exposed to intense electrical shock; (2) experimental subjects, previously trained to respond on a fixed vii ratio of six responses for liquid food reinforcement, were paired with target animals with the reinforcement contingency in effect; (3) experimental subjects were given a history of responding on a fixed ratio of six responses for positive reinforcement in the presence of shock, and finally this group was paired with experimentally naive targets when both the reinforcement and shock variables were present. Pairing experimental animals without shock did not cause attack, nor was bar-pressing behavior appreciably disrupted. Only when electrical shock was imposed upon pairs did attack occur. Furthermore, attack behavior severely reduced operant responding and there appeared to be no recovery of response rates over several sessions.

The purpose of this investigation was to provide quality dynamic strength properties for a solid grade severe-weather (SW) brick material and to illustrate the need for careful evaluation of the strain-rate effects on geomaterials. A split Hopkinson pressure bar (SHPB) was used to perform a series of tests on specimens from a solid grade SW brick to determine the mechanical response of this material at high strain-rates. Both classical and modified SHPB tests were performed. The results from the classical SHPB tests provided evidence that modifications to the SHPB are necessary when testing geomaterials such as brick. To modify the SHPB, a small copper disk was placed at the impact end of the SHPB incident bar to increase the rise time of the initial pulse. The material response from the modified SHPB tests provided an average compressive strength of 104 MPa, which resulted in a dynamic increase factor of 1.42.

No description available.

The ability to produce power during competition is essential. Football requires explosive power in order to get off the ball faster, increase speed of the first step, and increase the height of the vertical jump. Most strength training professionals use the back squat to increase power of the lower extremities; however, as large forces are placed on the back, athletes are at greater risk for injury. The trap bar dead lift is similar to the back squat in movement and form, but the trap bar dead lift reduces the force on the lower back. After testing for maximum vertical jump,athletes at Timpview High School participated in a strength program using either back squats or trap bar dead lift for seven weeks. A pre-test, mid-test and post-test were performed to calculate the increase in maximum vertical jump, if any. It was found that neither lift was significantly different than the other when testing for maximum vertical jump. These results will allow strength training professionals to use the trap bar dead lift instead of the back squats in subjects similar to those participating in the study.

This thesis examines a bayhead bar in the western end of the Lake Ontario Basin with the purpose of determining the dominant factors in the process-response model. From former field examination of the bar, and through the collection of deep drill cores, an attempt has been made to establish former processes which acted in the area of the present bar, Presently, field study, especially through the collecting of drill cores, sediment samples and wind data and by logging of wave data and longshore movement, has led to an attempt to establish the effect of present processes acting on the bar. / Thesis / Bachelor of Arts (BA)

In this study, impact craters in water ice are modeled using the hydrodynamic code CTH. In order to capture impact craters in ice an equation of state and a material model are created and validated. The validation of the material model required simulating the Split Pressure Hopkinson Bar (SPHB) experimental apparatus. The SPHB simulation was first compared to experiments completed on Al 6061-T6, then the ice material model was validated. After validation, the cratering simulations modeled known experiments found in the literature. The cratering simulations captured the bulk physical aspects of the experimental craters, and the differences are described. Analysis of the crater simulations showed the damaged volume produced by the projectile was proportional to the projectile’s momentum. Also, the identification of four different stages in the crater development of ice (contact and compression, initial damage progression, crater shaping, and ejected damaged material) are described.

No description available.

This work pioneers the experimental acquisition of data relating to the heating effects of inter-bar currents and the frequency components of the main field rotating flux. Previous research in the field of inter-bar currents is reliant on theory and mathematical modeling. Yet, with the growing need for increasing machine efficiency; experimental application of conceptualized theoretical models of machine losses is paramount. Focusing specifically on inter-bar currents in a rotating stator induction machine revealed a correlation between the heat generated in the iron core and the presence of inter-bar currents. Using temperature sensing instrumentation, experimental data was gathered to determine the inter-bar current distribution along the length of the rotor bars during acceleration. Additionally, custom current transducers were implemented to directly measure the main field rotating flux. The results present a solid foundation for direct and indirect measurement of inter-bar currents. / Thesis / Master of Applied Science (MASc)

An experimental program was conducted to investigate the strength and deformations of deep beams reinforced with Carbon Fibre Reinforced Polymer (CFRP) longitudinal and transverse reinforcement. Two groups of beams were tested, with each group comprising three beams. Two of the three beams in each group were reinforced with CFRP bars while the third beam was reinforced with conventional rebars and the latter beam was used as a control specimen. Beams in group 1 had span-to-depth ratio of one, while those in group 2 had a span-to-depth ratio of two. Beams in both groups had height of 900 mm and width of 250 mm. All the beams were simply supported and were tested in four-point bending with the point loads applied at one-third of the span. The test results revealed no significant difference between the behavior of the FRP reinforced beams and the companion control beams. On the other hand due to lack of hooks at the ends of the CFRP bars, and the loss of bond between the CFRP fibres and the sand grains on the surface of the bar, the failure in the CFRP reinforced beams was caused by the loss of anchorage while in the steel reinforced beams, the failure was initiated by the yielding of the longitudinal steel, followed by the crushing of the horizontal compression strut, but the nodal zones did not fail in any of the beams. Consequently, it was concluded that CFRP reinforced deep beams could be designed using the current CSA method for conventional steel reinforced concrete deep beams, provided the anchorage or bond strength of FRP bars could be properly determined. The existing nodal efficiency factors for the CCC nodal zones, as given in the CSA A23.3. standard, could be applied to CFRP reinforced beams while the corresponding factor for the CCT zone may be conservatively assumed to be 0.68. Finally, despite the linear elastic behavior of CFRP reinforcement, deep beams reinforced with CFRP bars could be designed using strut and tie models. / Thesis / Master of Applied Science (MASc)

The Interactive Video and Data System is a multidisciplinary research project involving the creation of a means for people to interact with television and printed media without the addition of expensive hardware as required by most interactive systems available today. The IVDS system consists of a Consumer Control Unit which transmits user requests, a Repeater Unit which receives transmissions from the CCUs, and a Host System which takes appropriate actions for user demands. This thesis follows the evolution of the original CCU prototype as more capabilities are added and hardware platforms are changed, focusing on the addition of a bar code interface to the CCU. / Master of Science