No description available.

Novel printed slot antennas are demonstrated in this thesis. For the linear polarization design, CPW-fed strip-loaded square slot antenna is presented for achieving broadband operations. For the circular polarization, two novel antenna designs are also presented¡Fone is a CPW-fed square slot antenna with an inverted L tunning stub, and the other is a microstrip line-fed square slot antenna with a conducting strip from ground plane for broadband circularly polarized radiation. Finally, an antenna design having compact size and broadband characteristic is shown.

Problem gambling is a growing social concern that results in debt, lost jobs, broken families, and at times, suicide. Slot machines are the most popular and most addictive form of gambling, generating nearly 70% of annual profits for the commercial casino industry in North America. Behavioral researchers have identified variables that establish and maintain problem gambling on slot machines, and the data reveal characteristics that influence preference for specific games, and subsequently, time spent engaged with specific machines. A degree of variability has been reported in the outcomes observed across participants and studies; such variability may be influenced by generic features of the games used by researchers utilizing a “one machine suits all” approach to slot research, i.e., within most studies a single machine is used for all participants rather than chosen according to participant preference for the machine or features therein. The following set of studies aimed to investigate variables related to slot machine selection, gambler preference for structural characteristics, and the reinforcing effectiveness of the machine on gambling behavior. The first of three experiments evaluated participant preference for functional and structural characteristics of popular three-, four- and five-reel electronic Vegas-style slot machines according to (a) a Likert rating scale of attitudes toward the machines, (b) forced ranking of most-preferred machines, and (c) a paired-stimulus preference assessment. Experiment II utilized a series of multiple schedules randomized across participants to examine differences in the rate of play when participants gambled on their most- and least-preferred machines. In Experiment III, the reinforcing effectiveness of the machines was evaluated. Participants engaged in an arbitrary task to gain access to their highest- and least-preferred machines as indicated in Experiment I. Response effort during the work task was evaluated under a progressive ratio schedule of reinforcement to determine the degree to which the individual would work to gain access to the machine. Participant break points were compared across the two conditions. Results of Experiment I yielded significant differences in the degree to which participants rated the machines: three-reel machines and those displaying a win were rated significantly higher in the attitude assessment when compared to four- or five-reel machines, and when compared to those with a loss, respectively. During the forced ranking procedure, participants again selected three-reel machines significantly more frequently in their “top five” favorite machines than four- or five-reel options. Last, when subjected to the paired stimulus preference assessment, participants selected three-reel machines on a significantly higher percentage of trials than five-reel alternatives. Results of Experiment II demonstrated that rate of play on high-preference machines is on average, faster than rate of play on lower-preference machines, and results from Experiment III yielded on average, higher break points in participant responding when offered the opportunity to gamble on high-preference slot machines following a response requirement than when offered a low-preference option; however, the average rate of response on the work task that led to machine access was lower during high-preference conditions than low-preference conditions. Implications of these findings for the gambling literature and for the effective prevention and treatment of disordered slot machine gambling are discussed.

Convection at the interior surface of a building represents a significant portion of the heat transfer in office buildings with large glazing areas. While a large number of these office buildings utilize ceiling slot diffusers at the glazed building perimeter, convection correlations specific to these diffusers have not yet been investigated. This paper describes convection correlations developed for ceiling slot diffusers and examines the effect of temperature, various window geometries, and diffuser jet momentum on these correlations. The paper also examines the effect of venetian blinds on the overall correlations at various blind angle configurations: open, partially open, and closed. The results of the examined phenomena are validated in both heating and cooling conditions. All together, this paper represents the effort of over 100 individual experiments. The results show that forced convection is dominant at all air flow rates, and correlations are developed as a function of air volumetric flow rate with supply air temperature utilized as the reference. The correlations are found to rely only on window position, and are independent of temperature difference between surface and supply, diffuser position, and diffuser jet momentum. With respect to the blinds, the only relevant parameter is the angle of the blinds except when the blinds are open. When the blinds are open and at 45º, convective heat transfer is enhanced. Conversely, convection is decreased when the blinds are closed and at -45º. There is also a decrease in the convective heat transfer with a full window in contrast to a half window when the blinds are open. Finally, there is little difference between the convection correlations developed for heated and cooled environments. / text

Research has shown that children categorize words in terms of taxonomic and slot-filler strategies. Monolingual children were thought to shift from a slot-filler to taxonomic strategy between the age of five and eight. The aim of this study is to analyze the way Mandarin-English bilingual children organize their lexical-semantic system through the use of a category-generation task that investigate taxonomic and slot-filler organizational strategies in each language. There were 53 Mandarin-English bilingual participants (between 4 and 7 years of age) included in this study. Participants were asked to name as many items as they could think of in slot-filler and taxonomic conditions in English and Mandarin. The results indicate greater performance in English than Mandarin in children who were five years or older. Four-year-old bilingual children produced comparable number of items in both slot-fill and taxonomic condition, but the five-, six-, and seven-year-old bilingual children showed greater performance in the taxonomic condition. Children performed better for the animal than the clothes category, and better for the clothes than the food category. These findings, while largely consistent with existing literature, suggest that the slot-filler to taxonomic shift may take place at an earlier age compared to monolingual children. / text

No description available.

No description available.

No description available.

No description available.

The power generation industry in the state of Victoria, Australia stands to gain significantly from process improvements and optimization which can potentially lead to cleaner production of cost effective electricity. The efficient operation of lignite based tangentially-fired combustion systems depends on critical issues such as ignition and combustion of the fuel, which are largely controlled by burner aerodynamics. The geometry of the burner and the ratio of velocities between the primary and secondary jets play an important role in achieving stable combustion, high burnout of fuel, low production of pollutants and control of fouling. Slot-burners are a vertically aligned stack of rectangular nozzles delivering primary fuel and secondary air jets, and are commonly used in tangentially-fired boilers. To obtain a better understanding of the overall combustion process, it is important to understand the aerodynamics of jet development from these burners. The starting point of this research was a CFD investigation of aerodynamics in the near-burner region of isolated rectangular slot-burners, using isothermal conditions, for various secondary to primary jet velocity ratios (φ). Cross-flow was then added to replicate a near-burner flow field similar to that found in a tangentially-fired furnace and the effect of changing φ in the near-burner region of the developing jets was again investigated. Experiments were carried out on an isothermal physical-burner model to obtain mean velocity and turbulent statistics for different nozzle geometries and a range of φ. A computational fluid dynamics investigation of these same jets was also performed to gain further insights into the complexities of flow field with experimental results used to validate CFD predictions. The primary jet substantially deviated from the geometric axis of the burner towards the furnace wall and became very unstable for higher φ. The causes of unfavourable aerodynamics were discussed and suggestions were made on possible remedies for such behaviour. Conventional lignite combustion in a full-scale tangentially-fired furnace was modelled. The model was used to assess the possibility of utilizing a new type of mechanically thermally dewatered (MTE) coal in existing furnaces.