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Thesis (M.A.) -- Central Connecticut State University, 1998. / Thesis advisor: Dr. Marc Goldstein. "...in partial fulfillment of the requirements for the degree of Master of Arts in Psychology." Includes bibliographical references (leaves 28-31).

Thesis (M. S.)--Aerospace Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Dr. Dimitri Mavris; Committee Member: Dean Ward; Committee Member: Dr. Daniel Schrage; Committee Member: Dr. Danielle Soban; Committee Member: Dr. Sriram Rallabhandi; Committee Member: Mathias Emeneth.

Thesis (Ph. D.)--Brigham Young University. Dept. of Instructional Psychology and Technology, 2004. / Includes bibliographical references (p. 103-106).

Gelatinous zooplankton are characterised as different from other planktonic taxa due to the high relative water content of their tissues. This thesis investigates whether elevated somatic water content (expressed here as carbon percentage) has effects on the biology of zooplankton. My approach was to examine this at a range of scales with a variety of approaches, ranging from experiments on individual ephyra larvae of Aurelia aurita, through analysis of a zooplankton time series at the Plymouth L4 station, up to a large scale meta-analysis of zooplankton growth and body composition data. In this meta-analysis, carbon percentage varied continuously across the range of the zooplankton, ranging from 0.01% to 19.02% of wet mass, a difference of over three orders of magnitude. Specific growth rate (g, d-1) was negatively related to carbon percentage, both across the full range of zooplankton species, and within the subset of taxa traditionally classified as gelatinous. The addition of carbon percentage to models of zooplankton growth rate based on carbon mass alone doubled explanatory power. I present an empirical equation of maximum (food saturated) zooplankton growth that incorporates carbon mass and carbon as a percentage of wet mass. Applying this equation to a natural assemblage near Plymouth yielded sometimes double the secondary production, as compared to a simpler model based on crustacean growth. Both interspecifically and intraspecifically, carbon percentage was negatively related to carbon mass; more gelatinous taxa tended to have higher carbon masses. During the early development of Aurelia aurita ephyrae, carbon percentage was found to decrease from 2.36% (an intermediate value between crustaceans and classical gelatinous zooplankton) down to 0.1%, the adult value for Aurelia aurita. Juvenile forms of gelatinous taxa are often poorly sampled and their intermediate carbon percentages may help to form a continuum between those of crustaceans and adult cnidarians and ctenophores. As ingestion in the ephyrae was related to their diameter, models suggest that this dilution resulted in an increase in carbon-specific ingestion rate by an estimated 28% relative to an ephyra that did not dilute through development. At the species level, carbon percentage was negatively related to indices of temporal variation in numerical density but not related to rate of population increase. A wide variety of zooplanktonic taxa of different carbon percentages were found to increase in population at a rate that could be considered as forming a bloom. Likewise many gelatinous taxa at L4 did not form blooms. Thus the frequent reference to “jellyfish blooms” reflects, in part, the fact that unlike the other zooplankters that regularly reach even higher carbon concentrations, gelatinous taxa are simply more noticeable to the eye when at these concentrations. Calculating the carbon percentage of whole assemblages could be useful for investigating the influence of environmental parameters on zooplankton. Taken together, these results demonstrate the benefits of explicitly recognising the decoupling of metabolic and ecological body size seen in the gelatinous zooplankton.

No description available.

Cloud computing is a constantly developing topic that reaches most of the people in the world on a daily basis. Almost every website and mobile application is hosted through a cloud provider. Two of the most important metrics for customers is performance and availability. Current tools that mea- sure availability are using the Internet Control Message Protocol (ICMP) to monitor availability, which has shown to be unreliable. This thesis suggests a new way of monitoring both availability and response time by using Hypertext Transfer Protocol (HTTP). Through HTTP, we are able to reach both the front-end of the cloud service (just as ICMP), but also deeper, to find failures in the back-end, that ICMP would miss. With our monitoring tool, we have monitored five different cloud data centers during one week. We found that cloud providers are not always keeping their promised SLA and it might be up to the cloud customers to reach a higher availability. We also perform load tests to analyze how vertical and horizontal scaling performs with regards to response time. Our analysis concludes that, at this time, vertical scaling outperforms horizontal scaling when it comes to response time. Even when this is the case, we suggest that developers should build applications that are horizontally scalable. With a horizontally scalable application and our monitoring tool combined, we can reach higher availability than is currently possible.

Cloud computing’s growing popularity is based on the cloud’s flexibility and the availability of a huge amount of resources. Today, cloud providers offer a wide range of predefined solutions, VM (virtual machine) sizes and customization differing in performance, support and price. In this thesis it is investigated how to achieve cost minimization within specified performance goals for a commercial service with computation occurring in a repetitive pattern. A promising multilevel queue scheduling and a set of auto-scaling rules to fulfil computation deadlines and job prioritization and lower server cost is presented. In addition, an investigation to find an optimal VM size in the sense of cost and performance points out further areas of cloud service optimization.

The effects of scaling a cavity with respect to a fixed incoming boundary layer thickness on its flow dynamics and control was studied experimentally. Three cavity models with constant length-to-depth ratio of 5 and length-to-width ratio of 2 and with corresponding linear dimensions in the ratio 0.5 : 1 : 2 were tested at freestream Mach number 0.71. Additionally, the 0.5 and 1 scale models were tested at freestream Mach number of 0.85. The experiments involved timeaveraged pressure measurements, unsteady pressure measurements, and PIV measurements. Time-averaged pressure measurements made at the floor were used to study the ’flow-type’ of the cavities. Unsteady pressure measurements were used to study the acoustic characteristics of the cavity. The cavity length-to-boundary layer thickness ratios tested were 10, 20 and 40. The Cp distribution on the clean cavities indicated a change in the cavity flowtype with change in the cavity scale. Varying the L/δ from 10 to 40 changed the cavity flow-type from open to transitional. Analysis of the frequency spectra of the cavity revealed an increase in tonal amplitudes and OASPL with increasing L/δ . The PIV measurements indicated that this could be caused by an increase in energy exchange between the freestream and the cavity. The velocity magnitudes inside the cavities were found to increase with increase in L/δ . A comparative study of different passive control methods on the largest cavity showed that leading-edge spoilers were superior in cavity tone suppression. Of these, the effectiveness of a sawtooth spoiler on the three cavities of different scales was tested. The results showed that while the spoiler was effective in eliminating tones and suppression of noise for the smaller cavities, it was unable to eliminate the tones completely for the largest cavity. To find the correct method for scaling the spoilers with the cavity dimensions, different spoiler heights were tested on the three cavities. The results showed that the cavity noise suppression for a given cavity attains saturation level at a particular spoiler height, called the critical spoiler height. An increase in spoiler height beyond the critical spoiler height was found to have no effect on the noise suppression. It is also found that this critical spoiler height can be scaled with the length of the cavity (for given L/D, M and spoiler profile) irrespective of the boundary layer thickness.

published_or_final_version / Psychology / Master / Master of Philosophy