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The latest advancements in mobile device technology are putting ever-higher demands for throughput of wireless networks. This is threatening to outpace the ability of service providers to deploy the necessary infrastructure. Fifth-Generation Mobile Network (5G) technology is experiencing rapid adoption as part of the effort to meet demand, and along with it researchers are continuously seeking new metrics and models for use in predicting the limits of current and future network infrastructure. To succeed, it is key that they have access to methods for simple, effective analysis of the wireless propagation channel in any given location. The typical laboratory test environment lacks the unpredictability and uniqueness of real-world conditions. Additionally, it utilizes equipment whose specifications are often far removed from devices that are actually intended to operate on the mobile network, such as smartphones themselves. This work focuses on the nature of contemporary path loss models and their ability to accurately predict signal levels, seeking to validate their use against observed path loss behavior in outdoor line-of-sight (LOS) scenarios, where the number of active devices can vary significantly over short periods of time. These conditions are typical of public spaces such as parks and city streets where a large number of users may all simultaneously be accessing high-throughput services. To test their validity, statistics are provided for sets of data collected on foot in public spaces using a novel software utility developed expressly for this purpose. The models we use for comparing against our measured results include both experiential models that are built on other data sets, along with stastically-based, large-scale path loss models. These are compared as a function of distance from the base station (BS), and any unique characteristics of the local network are considered. Finally, a combination of environmental imagery, coverage maps with signal strength overlays, and the aforementioned model comparison are used to estimate the signal source and predict performance in nearby areas.

Indiana University-Purdue University Indianapolis (IUPUI) / The pathogenesis associated with toxoplasmosis is attributed to repeated rounds of the parasite lytic cycle, which has been shown to be regulated by calcium fluxes. However, little is known about the calcium homeostatic mechanisms utilized by T. gondii. Recently, our lab has identified a novel protein-TgEFP1 (TGGT1_255660), which is predicted to bind Ca2+ through its two EF-hand domains. Interestingly, TgEFP1 showed a unique dual localization at the PLV/ELC and the PV of the parasite. Previous work showed that the PLV/ELC harbors other ion binding and conducting proteins that are important for parasite survival and propagation. However, the function of this compartment in the parasite is unknown. Therefore, I hypothesize that the PLV/ELC, through the function of TgEFP1, plays a key role in calcium homeostasis of T. gondii. To test this hypothesis, we sought to characterize the function of TgEFP1 during the parasite lytic cycle and determine TgEFP1 interacting proteins that also localize to the PLV/ELC. Partial permeabilization and ultrastructure expansion microscopy techniques confirmed the dual localization of TgEFP1 at the PLV/ELC and the PV. TgEFP1 knockout parasites exhibited several phenotypic defects including a faster lytic rate, shorter intracellular cycle, and were more sensitive to calcium ionophore treatment. Signal peptide deletion led to a mislocalization of TgEFP1 as cytosolic puncta, while mutations at key calcium coordinating residues lead to exclusive localization of TgEFP1 at the PV. Lastly, immunoprecipitation assays followed by LC-MS/MS identified a novel lectin-like protein- TgLectin (TGGT1_258950) as a direct interactor of TgEFP1-HA. Collectively, these findings support that through the function of TgEFP1, the PLV/ELC, plays a key role in calcium-dependent processes during the lytic cycle of the parasite.

Background Metaballs is a method that can be applied to multiple areas, for example creating clouds and water drop simulations. This thesis looks in into thepossibility of using metaballs as a technique for fire propagation.Objectives The aim of this thesis is to investigate if metaballs can be used asa method for fire propagation in comparison to a method that has been used inmultiple games already, a grid method. The comparison was categorized into two;degree of realism in each methods spreading pattern, and how well they performregarding execution time in different scenarios.Methods A user study was conducted to determine how realistic each method isaccording to the users. The study consisted of a survey, remotely done from home,in which the participants were asked to rate the degree of realism on different clips ofthe methods of fire propagation. As a point of reference for judging fire propagation,the participants also watched two videos of actual fires spreading. To evaluate theperformance of the methods they were exposed to different scenes containing differentamounts of objects the methods had to process.Results The user study concluded that there was no significant difference in themethods spreading regarding its realism. In total, 32 participants with the age rangeof 19 to 77 volunteered for the study. The performance tests concluded that theproposed method did not perform as good as the grid method, with an average often times the execution time.Conclusion The conclusion from the user study is that the results from the userstudy did not show any significant difference between the two methods. Performancewise however, the grid was proven to be a better alternative.

Scintillation is one of the most common statistics in the literature of mathematical modeling of laser propagation through random media. One approach to estimating scintillation is through the Rytov approximation, which is limited to weak atmospheric turbulence. Recently, an improvement of the Rytov approximation was developed employing a linear filter function technique. This modifies the Rytov approximation and extends the validity into the moderate to strong regime. In this work, an expression governing scintillation of a Gaussian beam along an uplink slant path valid in all regimes of turbulence is presented, as well as results for the limiting cases of a plane wave and a spherical wave.

In a packet radio network, multiple terminals broadcast information over a shared communications medium. Messages are transmitted from a source terminal to a destination terminal over multiple relays or hops. The actions of one terminal in the network directly affect the actions of other terminals within its range. The analysis of packet radio networks is complex because system performance depends on the topology of the terminals in the network along with the random access protocol used. Researchers have been unable to model a packet radio network in its most general form. In this project, a model is developed for specific topologies of a packet radio network with a given random access protocol. The sponsor of this project has developed a packet radio network for an indoor wireless alarm system. At the start of the project, the effect of message collisions on system performance was unknown. As a result of this research, a collision model for the network has been developed for topologies of four, five, and six alarm units. The model has been validated with actual system testing. Furthermore, the effects of indoor propagation on system performance have been studied. The results of this work have led to the development of an installation plan for the indoor wireless alarm system. / Master of Science

This thesis presents the results of a 28 GHz continuous-wave (CW) diffraction measurement campaign in the Washington, DC area. It describes the measurement approach including information on equipment and testing methods. Also described are the various parameters that affected the diffraction loss. Observed diffraction losses showed little dependence on polarization and building material. For diffraction angles greater than 5 degrees, a simple linear equation was fit to the data and accurately describes the diffraction loss. A logarithmic equation describes the dependence at smaller angles. The model developed shows very good agreement with theory and other measurements. Also included are an overview of the fixed wireless industry, a discussion of system design issues, and a review of the historical and mathematical development of diffraction theory. / Master of Science

Digital Elevation Models (DEMs) are computer-generated representations of the earth's surface. These surfaces can be used to predicted Line-of-Sight (LOS) radio propagation. DEM resolution can affect the results of this prediction. This study examines the effect of DEM resolution on accuracy by comparing varied resolution terrain data for a portion of Blacksburg, Virginia using the prediction of ESRI's ArcView® viewshed algorithm. Results show that resolutions between one-meter and thirty-meters have little effect on the aggregate accuracy of the viewshed. / Master of Science

No / In this paper, the seasonal variations of vertical refractivity gradients and statistics of anomalous Refractive Conditions in the United Arab Emirates (UAE) have been analyzed. Nine years of local radiosonde meteorological data, from 1997 to 2005, for the lowest atmospheric layer above the ground surface have been used. Monthly variations and cumulative distributions of refractivity gradients in the first 100 meters of the atmosphere are presented.