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Description
The purpose of this investigation is to computationally investigate instabilities appearing in the wake of a simulated helicopter rotor. Existing data suggests further understanding of these instabilities may yield design changes to the rotor blades to reduce the acoustic signature and improve the aerodynamic efficiencies of the aircraft. Test cases of a double-bladed and single-bladed rotor have been run to investigate the causes and types of wake instabilities, as well as compare them to the short wave, long wave, and mutual inductance modes proposed by Widnall[2]. Evaluation of results revealed several perturbations appearing in both single and double-bladed wakes, the origin of which was unknown and difficult to trace. This made the computations not directly comparable to theoretical results, and drawing into question the physical flight conditions being modeled. Nonetheless, they displayed a wake structure highly sensitive to both computational and physical disturbances; thus extreme care must be taken in constructing grids and applying boundary conditions when doing wake computations to ensure results relevant to the complex and dynamic flight conditions of physical aircraft are generated.
ContributorsDrake, Nicholas Spencer (Author) / Wells, Valana (Thesis director) / Squires, Kyle (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2014-12
Description
The increasing civilian demand for autonomous aerial vehicle platforms in both hobby and professional markets has resulted in an abundance of inexpensive inertial navigation systems and hardware. Many of these systems lack full autonomy, relying on the pilot's guidance with the assistance of inertial sensors for guidance. Autonomous systems depend heavily on the use of a global positioning satellite receiver which can be inhibited by satellite signal strength, low update rates and poor positioning accuracy. For precise navigation of a micro air vehicle in locations where GPS signals are unobtainable, such as indoors or throughout a dense urban environment, additional sensors must complement the inertial sensors to provide improved navigation state estimations without the use of a GPS. By creating a system that allows for the rapid development of experimental guidance, navigation and control algorithms on versatile, low-cost development platforms, improved navigation systems may be tested with relative ease and at reduced cost. Incorporating a downward-facing camera with this system may also be utilized to further improve vehicle autonomy in denied-GPS environments.
ContributorsPolak, Adam Michael (Author) / Rodriguez, Armando (Thesis director) / Saripalli, Srikanth (Committee member) / Hannan, Mike (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2014-12
Description
While public transit systems are perceived to produce lower GHG emission intensities per passenger miles traveled (PMT) and per vehicle miles traveled (VMT), there is a limited understanding of emissions per PMT/VMT across cities, or of how emissions may change across modes (light, metro, commuter, and bus) and time (e.g., with changing electricity mixes in the future). In order to better understand the GHG emissions intensity of public transit systems, a comparative emissions assessment was developed utilizing the National Transit Database (NTD) which reports energy use from 1997 to 2012 of rail and bus systems across the US. By determining the GHG emission intensities (per VMT or per PMT) for each mode of transit across multiple years, the modes of transit can be better compared between one another. This comparison can help inform future goals to reduce GHG emissions as well as target reductions from the mode of transit that has the highest emissions. The proposed analysis of the NTD and comparison of modal emission intensities will be used to develop future forecasting that can guide public transit systems towards a sustainable future.
ContributorsCano, Alex (Author) / Chester, Mikhail (Thesis director) / Seager, Thomas (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2014-12
Description
The price charged between related parties for the transfer of goods, services, or intangibles, is known as a transfer price. A taxpayer is required to set its transfer price at arm's-length, similar to what would be charged to an unrelated party, to prevent a taxpayer from greatly reducing its global tax by shifting profits from its U.S. entity to an entity located in a jurisdiction with a lower tax rate. Section 482 of the Internal Revenue Code and its associated regulations advises taxpayers on the various methods to calculate its transfer price. These include: the Comparable Uncontrolled Transaction (CUT) method, the Comparable Profits Method (CPM), and the Profit Split Method. Section 482 also grants the Internal Revenue Service (IRS) the authority to allocate a corporation's transfer price if it is not at arm's-length. With millions and sometimes billions of dollars at stake, it is important for the IRS to resolve the incredibly complex issue of transfer pricing without placing an unnecessary burden on U.S. corporations.
ContributorsWilliams, Gary Spencer (Author) / Goldman, Donald (Thesis director) / Levendowski, Glenda (Committee member) / Barrett, The Honors College (Contributor) / WPC Graduate Programs (Contributor) / School of Sustainability (Contributor) / School of Accountancy (Contributor)
Created2014-12
Description
In this project, I investigated the ecosystem services, or lack thereof, that landscape designs created in terms of microclimate modification at 11 residential homes throughout the Phoenix Metro Area. I also created an article for the homeowners who participated, explaining what I did and how they could apply my research. My research question was how a person can achieve a comfortable outdoor climate in their yard without over-using scarce water resources. I hypothesized that there would be a negative correlation between the maximum air temperature and the percent shade in each yard, regardless of the percent grass. I analyzed the data I collected using the program, R, and discovered that my hypothesis was supported for the month of July. These results are in line with previous studies on the subject and can help homeowners make informed decisions about the effects their landscaping choices might have.
ContributorsBarton, Erin Michaela (Author) / Hall, Sharon (Thesis director) / Ruddell, Benjamin (Committee member) / Spielmann, Katherine (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor)
Created2014-05
Description
The United States criminal justice system seemingly contradicts the staples of freedom that the country was founded upon. Given that the U.S. leads the world in rate of imprisonment, "the land of the free" is actually better described as "the land of the imprisoned". Yet despite such meteoric imprisonment rates, there is no evidence that United States citizens commit more crimes than citizens of other countries. This leads to the deduction that there is a fundamental difference between the United States criminal justice system and that of other countries. While different does not always mean worse, it is undoubtable that the United States is currently facing a financial dilemma due to housing so many criminals. Further, prosecution of such a large number of citizens has led to a dichotomy in society that perpetuates recidivism among those imprisoned. Thus, reform activists are growing in number as the incarceration problem continues to perpetuate. Information Measurement Theory, a modern school of thought, is applied in this paper in order to develop practical improvements to the American criminal justice system. Information Measurement Theory is aptly named because it proposes universal axioms based upon the various levels of information perceived by human beings. It has already improved performance dynamics in various areas of business; therefore it has a great opportunity for success in refining the American prison industry. Staples of Information Measurement Theory allow the individual to simplify complex situations. Hence, it can be applied to simplify the conditions that have led to the current U.S. incarceration predicament. Three different specific areas of U.S. criminal justice will be addressed, and solutions will be presented that are complimentary to Information Measurement Theory fundamentals.
ContributorsMcLeod, Ian Nicholas (Author) / Kashiwagi, Dean (Thesis director) / Kashiwagi, Jacob (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Mechanical Engineering Program (Contributor) / Del E. Webb School of Construction (Contributor)
Created2015-05
Description
The generation of walking motion is one of the most vital functions of the human body because it allows us to be mobile in our environment. Unfortunately, numerous individuals suffer from gait impairment as a result of debilitating conditions like stroke, resulting in a serious loss of mobility. Our understanding of human gait is limited by the amount of research we conduct in relation to human walking mechanisms and their characteristics. In order to better understand these characteristics and the systems involved in the generation of human gait, it is necessary to increase the depth and range of research pertaining to walking motion. Specifically, there has been a lack of investigation into a particular area of human gait research that could potentially yield interesting conclusions about gait rehabilitation, which is the effect of surface stiffness on human gait. In order to investigate this idea, a number of studies have been conducted using experimental devices that focus on changing surface stiffness; however, these systems lack certain functionality that would be useful in an experimental scenario. To solve this problem and to investigate the effect of surface stiffness further, a system has been developed called the Variable Stiffness Treadmill system (VST). This treadmill system is a unique investigative tool that allows for the active control of surface stiffness. What is novel about this system is its ability to change the stiffness of the surface quickly, accurately, during the gait cycle, and throughout a large range of possible stiffness values. This type of functionality in an experimental system has never been implemented and constitutes a tremendous opportunity for valuable gait research in regard to the influence of surface stiffness. In this work, the design, development, and implementation of the Variable Stiffness Treadmill system is presented and discussed along with preliminary experimentation. The results from characterization testing demonstrate highly accurate stiffness control and excellent response characteristics for specific configurations. Initial indications from human experimental trials in relation to quantifiable effects from surface stiffness variation using the Variable Stiffness Treadmill system are encouraging.
ContributorsBarkan, Andrew Robert (Author) / Artemiadis, Panagiotis (Thesis director) / Santello, Marco (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2015-05
Description
The value of data in the construction industry is driven by the actual worth or usefulness the data can provide. The revolutionary method of Best Value Performance Information Procurement System implemented into the industry by the Performance Based Studies Research Group at ASU optimizes the value of data. By simplifying the details and complexity of a construction project through dominant and logical thinking, the Best Value system delivers efficient, non-risk success. The Best Value model's implementation into industry projects is observed in the PBSRG Minnesota projects in order to improve data collection and metric analysis. The Minnesota projects specifically have an issue with delivering Best Value transparency, the notion that the details of project data should be used to support dominant ideas. By improving and simplifying the data collection tools of PBSRG, Best Value transparency can be achieved more easily and effective, in turn improved the Best Value system.
ContributorsMisiak, Erik Richard (Author) / Kashiwagi, Dean (Thesis director) / Kashiwagi, Jacob (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2015-05
Description
As the poverty level increases in Arizona, so does the opportunity gap between high- income and low-income students. We believe that all youth regardless of their zip code, the color of their skin, or their family background should see themselves as leaders and scholars in the community. Access to higher education, quite simply should be attainable for all students. The New American University charter that ASU has adopted is inspiring and groundbreaking. We believe this charter underscores the significance of equal access to education. The REACH program embraces the urgency of educational inequity, by enhancing the potential success of high school teenagers, who attend the Boys & Girls Club \u2014 Ladmo Branch in Tempe, Arizona. REACH empowers youth to develop stronger leadership skills, while becoming more involved in their community. We provide an opportunity for these teens to engage in leadership discussions, receive college mentoring/tutoring, and connect with the community and resources that Arizona State University (ASU) has to offer. It is our hope that every REACH teen is inspired to apply for college. REACH strives to provide any support the teens require to be successful throughout the college testing and admission process. REACH works with multiple communities at Arizona State University including the Pat Tillman Scholars, Devils' Advocates, Honors Devils, Changemaker Central, Barrett, The Honors College and W. P. Carey School of Business to organize and lead a group of teens through a remarkable curriculum that will shape the way they view cultural diversity, educational achievement, and leadership. The weekly meetings consist of discussions, creative team-building, critical thinking exercises, and cultural awareness experiences. Demonstrating to the teens, administrators, volunteers, mentors, and tutors the rich culture that Tempe has to offer and the skills and experience that they have to offer their community as well. In this thesis will we present our work developing and implementing the REACH program at the Ladmo Branch of the Tempe Boys and Girls Club from the Spring of 2013 through the Spring of 2015. We will describe the structure of REACH, our weekly leadership curriculum, our assessment and evaluation method, and the supplemental programs that we instituted (i.e., tutoring and mentoring). We will reflect on our successes and the challenges that we faced over the span of three years. We will conclude our thesis with a critical analysis of the program as a whole in order to provide advice for others who want to create and engage in a sustainable, student lead, community action organization.
ContributorsBurba, Monica (Co-author) / Smith, Jenna (Co-author) / Mokwa, Michael (Thesis director) / Eaton, John (Committee member) / Barrett, The Honors College (Contributor) / School of Politics and Global Studies (Contributor) / School of Sustainability (Contributor) / School of Historical, Philosophical and Religious Studies (Contributor) / School of International Letters and Cultures (Contributor)
Created2015-05
Description
Sustainability has been a growing topic since the 1970’s, but is truly taking shape today as society is beginning to understand the necessity of protecting our environment. Business organizations are following this ‘megatrend’ and are beginning to incorporate sustainable initiatives in their organizations from the inside out. The sports industry is no exception as they are extremely influential over the millions of fans that follow them, whom have a strong affiliation with their favorite team. The Arizona Diamondbacks understand this responsibility and seek to be a leader in their community by creating many sustainable initiatives within their organization and community. The current problem the organization faces, is that much of the community are not aware of their environmental commitment. This is in part due to a lack of marketing within the organization and to the Arizona valley. This project analyzes the sports industry’s commitment to sustainability and how the Arizona Diamondbacks compare to industry leaders. Included is a detailed marketing plan for the organization comprised of current initiatives and of new initiatives that the Diamondbacks could potentially carry out. The implementation of this proposal could deem extremely beneficial as it would strengthen their identity, unify their employees and engage fans, which will make them feel a deeper affiliation with the organization. The Diamondbacks have made a commitment to the environment, but it is time to deepen that commitment, set an example for people in the Valley and in turn, spark social change.
ContributorsBauman, Jillian (Co-author) / Hopson, Emma (Co-author) / Eaton, John (Thesis director) / Kutz, Elana (Committee member) / Barrett, The Honors College (Contributor) / W. P. Carey School of Business (Contributor) / Department of Management (Contributor) / Department of Marketing (Contributor) / School of Sustainability (Contributor)
Created2015-05