Discrimination in Metropolitan Housing Markets: Phase 3 - Native Americans

This paper documents the results of a pilot paired testing program to examine the treatment of Native Americans by real estate agents in rental housing markets in three states and owner-occupied housing markets in one state. The study finds that the level of discrimination experienced by Native Americans in rental markets exceed those experienced by Hispanics, Blacks, and Asian-Americans.

Formal Contexts, Formal Concept Analysis, and Galois Connections

Formal concept analysis (FCA) is built on a special type of Galois connections called polarities. We present new results in formal concept analysis and in Galois connections by presenting new Galois connection results and then applying these to formal concept analysis. We also approach FCA from the perspective of collections of formal contexts. Usually, when doing FCA, a formal context is fixed. We are interested in comparing formal contexts and asking what criteria should be used when determining when one formal context is better than another formal context. Interestingly, we address this issue by studying sets of polarities.Comment: In Proceedings Festschrift for Dave Schmidt, arXiv:1309.455

A Mobile Self-Leveling Landing Platform for Small-Scale UAVs

This thesis presents a semi-autonomous mobile self-leveling landing platform designed to launch, recover and re-launch VTOL UAVs without the need for human intervention. The landing platform is rugged, lightweight and inexpensive, making it ideal for civilian applications that require a base station from which a rotorcraft UAV can be launched and recovered on terrain that is normally unsuitable for UAV operations. This landing platform is capable of self-leveling on rough terrain and inclined slopes, and can autonomously operate in remote locations for extended periods of time using large onboard lithium batteries and wireless communication. This thesis discusses the unique design aspects of this landing platform that set it apart from similar systems, describes the prototype vehicle, and shows experimental results to demonstrate the system is fully functional and meets all the primary design requirement

Master of Science

thesisA proposed site for the Department of Energy's Frontier Observatory for Research in Geothermal Energy (FORGE) is located in southwestern Utah, in the Milford Basin, west of the Mineral Mountains. This site is at the intersection of the Intermountain Seismic Belt and the Pahranagat Shear Zone. This area is known for geothermal energy and the Roosevelt Hot Springs power plant, east of FORGE, has been active since 1984. For FORGE to be successful, an induced seismicity mitigation plan is required. There have been 185 seismic events from 1850 to 2016 cataloged by the University of Utah Seismograph Stations (UUSS) in this area. In this study, I completed a noise analysis on the local seismometers IMU, NMU, and DWU and determined the capabilities for the seismic detection work. To lower the magnitude of completeness, subspace detection analysis was applied for the years 2010-2016 and the best events were relocated in a relative sense together with events from the UUSS catalog. The relocated events were analyzed through principal component analysis to determine their hypocentral geometric distribution. Within the study area, we determined a new potential fault just north of Milford, Utah and observed hypocentral geometries in the Mineral Mountains that are consistent with previously reported tectonic structures. Finally, with the additions to the UUSS catalog and completed work, we were able to complete a stability analysis to show that we successfully reduced the magnitude of completeness for the area during the time period of 2010-2016. These results have allowed a seismicity baseline to be established for the induced seismicity mitigation plan for FORGE

Comparing SSURGO Data versus Geospatial Field Measurements to Estimate Soil Texture and Infiltration Rate Classes in Glaciated Soils

The infiltration rate (IR) of water is a key soil property related to hydrological processes, soil health and ecosystem services. However, detailed measurements of IR in the field and/or laboratory are labor-intensive and expensive to perform. Soil judging in the field provides a rapid and inexpensive method to estimate IR classes based on soil texture, soil organic carbon/matter and soil structure. The objectives of this study were to classify and compare soil texture and IR for the A horizon across the 147-ha Cornell University Willsboro Research Farm using the Soil Survey Geographic (SSURGO) database and field-based measurements. Soil texture was the dominating factor to explain the general trend of Entisols \u3e Inceptisols \u3e Alfisols with regard to IR in the A horizon. In general, the variability in soil texture observed in field measurements was consistent with the variability reported in the SSURGO database, although the SSURGO representative values for soil texture did not completely match measured mean values for all soil map units. With the exception of one soil map unit, estimates of IR classes utilizing soil judging in the field criteria also were consistent when using either SSURGO or field-based data. Estimating infiltration rate classes for ecosystem services frameworks using geospatial analysis of field and/or SSURGO data can be enhanced with emerging technologies (e.g., sensors) and/or easily measured conventional soil properties

The Impact of Virtual Technology on Discipleship Training in a Small Group Context

Many contemporary churches face the difficulty of implementing the Great Commission’s mandate for making disciples (Matt 28:19-20). Occasional church attendance and a lack of participation in fellowship and ministries beyond the Sunday worship service reflect this difficulty. Discipleship has become even more challenging in the current climate of social distancing that has resulted from COVID-19 pandemic restrictions. Being separated physically from others exacerbates a growing predisposition to spiritual isolation, which in turn hinders development of discipleship; physical interaction has always been the main model for making disciples. The Great Commission’s description of discipleship (making disciples through going, baptizing, and teaching) is an observable, physical aspect of spiritual formation. Hence, the use of digital technology for virtual relationships for the purpose of making disciples is a new approach. This research project will propose a plan to enhance discipleship in the context of a small Anglican church in Yuma, Arizona. An integrated strategy will be used during this six-week video conferencing exercise to facilitate virtual fellowship, provide discipleship training, discuss spiritual formation processes, cultivate a posture of routine prayer, and encourage meditative Scripture reading. A Spiritual Fitness Test will be completed by the thirteen participants at the start and conclusion of the project to measure receptivity and growth. The project addresses a common discipleship problem with the added wrinkle of a global pandemic’s influence on the process. Although the project is based in one Anglican church in Yuma, Arizona, the results are expected to have wide application as modified to local needs and geography. The results demonstrated clear increases in spiritual formation in all categories and included requested for continued daily morning and evening prayer sessions. Those sessions have been continuing for more than a year following the project’s completion

Empirical Evaluation of Ground, Ceiling, and Wall Effect for Small-Scale Rotorcraft

Ground effect refers to the apparent increase in lift that an aircraft experiences when it flies close to the ground. For helicopters, this effect has been modeled since the 1950\u27s based on the work of Cheeseman and Bennett, perhaps the most common method for predicting hover performance due to ground effect. This model, however, is based on assumptions that are often not realistic for small-scale rotorcraft because it was developed specifically for conventional helicopters. It is clear that the Cheeseman-Bennett model cannot be applied to today\u27s multirotor UAVs. Experimental findings suggest that some of the conventional thinking surrounding helicopters cannot be applied directly to rotorcraft using fixed propellers at variable speeds (e.g. multirotors). A parametric multirotor-specific ground effect model is developed and presented to overcome some of the limitations in classical helicopter theory. Likewise, ceiling effect refers to the apparent increase in lift that a rotorcraft experiences when flying close to a ceiling or any similar surface that is present above the rotor(s). Ceiling effect is similar in principle to ground effect, and can be explained using a similar equation. Ceiling effect, however, was never explored in detail for conventional helicopters because large manned aircraft do not operate in enclosed spaces. For multirotors, the work presented in this dissertation suggests that the classical helicopter theory adequately describes ceiling effect performance. Wall effect is the phenomena that occurs when a rotorcraft flies near a vertical wall, and has the tendency to pitch towards the wall and be drawn into it. Wall effect is the least-understood of these three areas of interest. Wall effect has not been explored in great detail for any aircraft, and is addressed in detail in this dissertation. The recent widespread use of small-scale UAVs and the demand for increased autonomy when flying in enclosed environments has created a need for detailed studies of ground effect, ceiling effect and wall effect. Ultimately, this work provides foundations for the development of an improved UAV flight controller that can accurately account for various aerodynamic disturbances that occur near surfaces and structures to improve flight stability

A Structural Perspective of Antibody Neutralization of Dengue Virus

The four dengue viruses: DENV) are mosquito-borne flaviviruses and are considered the world\u27s most significant arboviruses in terms of worldwide disease burden. Symptoms of dengue disease are classified into dengue fever, a mild, febrile illness, and the potentially fatal severe dengue, which can include hemorrhaging and shock. Antibody protection against DENV correlates with the production of neutralizing antibodies against the envelope: E) glycoprotein. To understand the role of antibodies in DENV infection, we sought to dissect the relationship between epitope and function. Virologic studies had identified that the most potently neutralizing antibodies are against domain III: DIII) of the E protein. We have identified five epitopes within DENV DIII. Our data suggests that the most potently neutralizing antibodies are specific for a single serotype, while cross-reactive antibodies are relatively poorly neutralizing. Additionally, we were surprised to define neutralizing epitopes that were shown to be inaccessible on the surface of the virion in cryo-electron microscopy studies. Fine epitope mapping was used to define the epitopes of a panel of existing DENV-2 antibodies. Antibodies against the lateral ridge were the most potently neutralizing antibodies and reacted only with the DENV-2 serotype. The second epitope was centered on the DIII A-strand, and antibodies against this epitope reacted with several serotypes of DENV. Several poorly neutralizing antibodies reacted to all four DENV serotypes, as well as West Nile virus, a related flavivirus, mapped to the highly conserved AB loop of DIII. We expanded our studies of DIII-specific antibodies to the DENV-1 serotype. One antibody, E106, potently neutralized the five DENV-1 strains representing the five genotypes, and bound a composite epitope of the lateral ridge and A-strand epitopes. Despite the potency of E106-mediated neutralization, a combination of structural, biophysical, virologic data suggest that potent DENV-1 neutralization by E106 is coincident with bivalent engagement of the virus. Additionally, we determined the crystal structures of E111 bound to a novel fifth CC\u27 loop epitope on domain III: DIII) of the E protein from two different DENV-1 genotypes. The available atomic models of DENV virions revealed that the E111 epitope was inaccessible, suggesting that it recognizes an uncharacterized virus conformation. While the affinity of binding between E111 and DIII varied by genotype, we observed limited correlation with inhibitory activity. Instead, our results support the conclusion that potent neutralization depends on genotype-dependent exposure of the CC\u27 loop epitope. These findings establish new structural complexity of the DENV virion, which may be relevant for the choice of DENV strain for induction or analysis of neutralizing antibodies in the context of vaccine development

Empirical Evaluation of Ground, Ceiling, and Wall Effect for Small-Scale Rotorcraft

Ground effect refers to the apparent increase in lift that an aircraft experiences when it flies close to the ground. For helicopters, this effect has been modeled since the 1950\u27s based on the work of Cheeseman and Bennett, perhaps the most common method for predicting hover performance due to ground effect. This model, however, is based on assumptions that are often not realistic for small-scale rotorcraft because it was developed specifically for conventional helicopters. It is clear that the Cheeseman-Bennett model cannot be applied to today\u27s multirotor UAVs. Experimental findings suggest that some of the conventional thinking surrounding helicopters cannot be applied directly to rotorcraft using fixed propellers at variable speeds (e.g. multirotors). A parametric multirotor-specific ground effect model is developed and presented to overcome some of the limitations in classical helicopter theory. Likewise, ceiling effect refers to the apparent increase in lift that a rotorcraft experiences when flying close to a ceiling or any similar surface that is present above the rotor(s). Ceiling effect is similar in principle to ground effect, and can be explained using a similar equation. Ceiling effect, however, was never explored in detail for conventional helicopters because large manned aircraft do not operate in enclosed spaces. For multirotors, the work presented in this dissertation suggests that the classical helicopter theory adequately describes ceiling effect performance. Wall effect is the phenomena that occurs when a rotorcraft flies near a vertical wall, and has the tendency to pitch towards the wall and be drawn into it. Wall effect is the least-understood of these three areas of interest. Wall effect has not been explored in great detail for any aircraft, and is addressed in detail in this dissertation. The recent widespread use of small-scale UAVs and the demand for increased autonomy when flying in enclosed environments has created a need for detailed studies of ground effect, ceiling effect and wall effect. Ultimately, this work provides foundations for the development of an improved UAV flight controller that can accurately account for various aerodynamic disturbances that occur near surfaces and structures to improve flight stability