ASU Electronic Theses and Dissertations
This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.
In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.
Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.
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Description
This dissertation develops a framework for the analysis of fiscal sustainability among U.S. local governments. Fiscal sustainability is defined as a type of fiscal condition that allows a government to continue service provision now and in the future without introducing disruptive revenue or expenditure patterns. An assessment of local fiscal sustainability is based on three types of indicators: pension liability funding, debt burden, and budgetary balance. Three main factors affect a government's long-term financial condition: government structure, financial structure and performance, and local economic base. This dissertation uses a combination of the U.S. Census Bureau Annual Survey of Government Finances and Employment, the U.S. Census Bureau Decennial Census, the Bureau of Labor Statistics data, and the Government Finance Officers Association financial indicators database to study the effects of the three factors on local fiscal sustainability. It is a pioneer effort to use government-wide accounting information from Comprehensive Annual Financial Reports to predict local fiscal sustainability status. The results of econometric models suggest that pension liability funding is most affected by the size of government, debt burden is most strongly associated with the size of local economic base; and budgetary balance is influenced by the degree of local own-source revenue diversification.
ContributorsGorina, Evgenia (Author) / Chapman, Jeffrey I. (Thesis advisor) / Herbst, Chris M. (Committee member) / Miller, Gerald J (Committee member) / Arizona State University (Publisher)
Created2013
Description
This dissertation is an exploratory study that examined the differences in perceptions about supply chain management strategy, topics, tools, and techniques between procurement professionals in public and private sector organizations. This was accomplished through a survey of procurement professionals in a Fortune 500 company and a municipality in Arizona. The data were analyzed to understand how perceptions of supply chain management differed within this sample and whether the differences in perceptions were associated with formal education levels. Key findings indicate that for this or similar samples, public procurement respondents viewed their organizations' approach to supply chain management as a narrow function within purchasing while private sector respondents viewed their organization's approach to supply chain management as a strategic purchasing perspective that requires the coordination of cross functional areas. Second, public procurement respondents reported consistent and statistically significant lower levels of formal education than private sector respondents. Third, the supply chain management topics, tools, and techniques seem to be more important to private sector respondents than the public sector respondents. Finally, Respondents in both sectors recognize the importance of ethics and ethical behavior as an essential part of supply chain management.
ContributorsHeller, Jacob (Author) / Cayer, Joseph (Thesis advisor) / Lan, Gerald (Committee member) / Eden, Catherine (Committee member) / Arizona State University (Publisher)
Created2013
Description
After a decade of efforts, accurate and affordable DNA sequencing continues to remain an important goal in current research landscape. This thesis starts with a brief overview of the recent updates in the field of DNA sequencing technologies followed by description of the nanofluidics route to single molecule DNA detection. Chapter 2 presents discusses carbon nanotube(CNT) based nanofluidics. The fabrication and DNA sensing measurements of CNT forest membrane devices are presented. Chapter 3 gives the background for functionalization and recognition aspects of reader molecules. Chapter 4 marks the transition to solid state nanopore nanofluidics. The fabrication of Imidazole functionalized nanopores is discussed. The Single Molecule detection results of DNA from Palladium nanopore devices are presented next. Combining chemical recognition to nanopore technology, it has been possible to prolong the duration of single molecule events from the order of a few micro seconds to upto a few milliseconds. Overall, the work presented in this thesis promises longer single molecule detection time in a nanofludic set up and paves way for novel nanopore- tunnel junction devices that combine recognition chemistry, tunneling device and nanopore approach.
ContributorsKrishnakumar, Padmini (Author) / Lindsay, Stuart (Thesis advisor) / He, Jin (Committee member) / Vaiana, Sara (Committee member) / Schmidt, Kevin (Committee member) / Arizona State University (Publisher)
Created2013
Description
The thesis studies new methods to fabricate optoelectronic Ge1-ySny/Si(100) alloys and investigate their photoluminescence (PL) properties for possible applications in Si-based photonics including IR lasers. The work initially investigated the origin of the difference between the PL spectrum of bulk Ge, dominated by indirect gap emission, and the PL spectrum of Ge-on-Si films, dominated by direct gap emission. It was found that the difference is due to the supression of self-absorption effects in Ge films, combined with a deviation from quasi-equilibrium conditions in the conduction band of undoped films. The latter is confirmed by a model suggesting that the deviation is caused by the shorter recombination lifetime in the films relative to bulk Ge. The knowledge acquired from this work was then utilized to study the PL properties of n-type Ge1-ySny/Si (y=0.004-0.04) samples grown via chemical vapor deposition of Ge2H6/SnD4/P(GeH3)3. It was found that the emission intensity (I) of these samples is at least 10x stronger than observed in un-doped counterparts and that the Idir/Iind ratio of direct over indirect gap emission increases for high-Sn contents due to the reduced gamma-L valley separation, as expected. Next the PL investigation was expanded to samples with y=0.05-0.09 grown via a new method using the more reactive Ge3H8 in place of Ge2H6. Optical quality, 1-um thick Ge1-ySny/Si(100) layers were produced using Ge3H10/SnD4 and found to exhibit strong, tunable PL near the threshold of the direct-indirect bandgap crossover. A byproduct of this study was the development of an enhanced process to produce Ge3H8, Ge4H10, and Ge5H12 analogs for application in ultra-low temperature deposition of Group-IV semiconductors. The thesis also studies synthesis routes of an entirely new class of semiconductor compounds and alloys described by Si5-2y(III-V)y (III=Al, V= As, P) comprising of specifically designed diamond-like structures based on a Si parent lattice incorporating isolated III-V units. The common theme of the two thesis topics is the development of new mono-crystalline materials on ubiquitous silicon platforms with the objective of enhancing the optoelectronic performance of Si and Ge semiconductors, potentially leading to the design of next generation optical devices including lasers, detectors and solar cells.
ContributorsGrzybowski, Gordon (Author) / Kouvetakis, John (Thesis advisor) / Chizmeshya, Andrew (Committee member) / Menéndez, Jose (Committee member) / Arizona State University (Publisher)
Created2013
Description
A void exists in public administration, criminology, and criminal justice research as it relates to the study of power in American policing agencies. This has significant ramifications for academia and practitioners in terms of how they view, address, study, and interpret behaviors/actions in American policing agencies and organizations in general. In brief, mainstream research on power in organizations does not take into account relationships of power that do not act directly, and immediately, on others. By placing its emphasis on an agency centric perspective of power, the mainstream approach to the study of power fails to recognize indirect power relationships that influence discourse, pedagogy, mechanisms of communication, knowledge, and individual behavior/actions. In support of a more holistic inquiry, this study incorporates a Foucauldian perspective of power along with an ethnographical methodology and methods to build a greater understanding of power in policing organizations. This ethnography of an American policing organization illuminates the relationship between the exercise of power and the objectification of the subject through the interplay of relationships of communication, goal oriented activities, and relationships of power. Specifically, the findings demonstrate that sworn officers and civilian employees are objectified distinctly and dissimilarly. In summary, this study argues that the exercise of power in this American policing organization objectifies the civilian employee as a second class citizen.
ContributorsBentley, Paul C (Author) / Catlaw, Thomas (Thesis advisor) / Musheno, Michael (Committee member) / Lucio, Joanna (Committee member) / Arizona State University (Publisher)
Created2013
Description
The work contained in this dissertation is focused on the optical properties of direct band gap semiconductors which crystallize in a wurtzite structure: more specifically, the III-nitrides and ZnO. By using cathodoluminescence spectroscopy, many of their properties have been investigated, including band gaps, defect energy levels, carrier lifetimes, strain states, exciton binding energies, and effects of electron irradiation on luminescence. Part of this work is focused on p-type Mg-doped GaN and InGaN. These materials are extremely important for the fabrication of visible light emitting diodes and diode lasers and their complex nature is currently not entirely understood. The luminescence of Mg-doped GaN films has been correlated with electrical and structural measurements in order to understand the behavior of hydrogen in the material. Deeply-bound excitons emitting near 3.37 and 3.42 eV are observed in films with a significant hydrogen concentration during cathodoluminescence at liquid helium temperatures. These radiative transitions are unstable during electron irradiation. Our observations suggest a hydrogen-related nature, as opposed to a previous assignment of stacking fault luminescence. The intensity of the 3.37 eV transition can be correlated with the electrical activation of the Mg acceptors. Next, the acceptor energy level of Mg in InGaN is shown to decrease significantly with an increase in the indium composition. This also corresponds to a decrease in the resistivity of these films. In addition, the hole concentration in multiple quantum well light emitting diode structures is much more uniform in the active region when Mg-doped InGaN (instead of Mg-doped GaN) is used. These results will help improve the efficiency of light emitting diodes, especially in the green/yellow color range. Also, the improved hole transport may prove to be important for the development of photovoltaic devices. Cathodoluminescence studies have also been performed on nanoindented ZnO crystals. Bulk, single crystal ZnO was indented using a sub-micron spherical diamond tip on various surface orientations. The resistance to deformation (the "hardness") of each surface orientation was measured, with the c-plane being the most resistive. This is due to the orientation of the easy glide planes, the c-planes, being positioned perpendicularly to the applied load. The a-plane oriented crystal is the least resistive to deformation. Cathodoluminescence imaging allows for the correlation of the luminescence with the regions located near the indentation. Sub-nanometer shifts in the band edge emission have been assigned to residual strain the crystals. The a- and m-plane oriented crystals show two-fold symmetry with regions of compressive and tensile strain located parallel and perpendicular to the ±c-directions, respectively. The c-plane oriented crystal shows six-fold symmetry with regions of tensile strain extending along the six equivalent a-directions.
ContributorsJuday, Reid (Author) / Ponce, Fernando A. (Thesis advisor) / Drucker, Jeff (Committee member) / Mccartney, Martha R (Committee member) / Menéndez, Jose (Committee member) / Shumway, John (Committee member) / Arizona State University (Publisher)
Created2013
Description
Microwave dielectrics are widely used to make resonators and filters in telecommunication systems. The production of thin films with high dielectric constant and low loss could potentially enable a marked reduction in the size of devices and systems. However, studies of these materials in thin film form are very sparse. In this research, experiments were carried out on practical high-performance dielectrics including ZrTiO4-ZnNb2O6 (ZTZN) and Ba(Co,Zn)1/3Nb2/3O3 (BCZN) with high dielectric constant and low loss tangent. Thin films were deposited by laser ablation on various substrates, with a systematical study of growth conditions like substrate temperature, oxygen pressure and annealing to optimize the film quality, and the compositional, microstructural, optical and electric properties were characterized. The deposited ZTZN films were randomly oriented polycrystalline on Si substrate and textured on MgO substrate with a tetragonal lattice change at elevated temperature. The BCZN films deposited on MgO substrate showed superior film quality relative to that on other substrates, which grow epitaxially with an orientation of (001) // MgO (001) and (100) // MgO (100) when substrate temperature was above 500 oC. In-situ annealing at growth temperature in 200 mTorr oxygen pressure was found to enhance the quality of the films, reducing the peak width of the X-ray Diffraction (XRD) rocking curve to 0.53o and the χmin of channeling Rutherford Backscattering Spectrometry (RBS) to 8.8% when grown at 800oC. Atomic Force Microscopy (AFM) was used to study the topography and found a monotonic decrease in the surface roughness when the growth temperature increased. Optical absorption and transmission measurements were used to determine the energy bandgap and the refractive index respectively. A low-frequency dielectric constant of 34 was measured using a planar interdigital measurement structure. The resistivity of the film is ~3×1010 ohm·cm at room temperature and has an activation energy of thermal activated current of 0.66 eV.
ContributorsLi, You (Author) / Newman, Nathan (Thesis advisor) / Alford, Terry (Committee member) / Singh, Rakesh (Committee member) / Arizona State University (Publisher)
Created2013
Description
This dissertation is focused on material property exploration and analysis using computational quantum mechanics methods. Theoretical calculations were performed on the recently discovered hexahydride materials A2SiH6 (A=Rb, K) to calculate the lattice dynamics of the systems in order to check for structural stability, verify the experimental Raman and infrared spectrospcopy results, and obtain the theoretical free energies of formation. The electronic structure of the systems was calculated and the bonding and ionic properties of the systems were analyzed. The novel hexahydrides were compared to the important hydrogen storage material KSiH3. This showed that the hypervalent nature of the SiH62- ions reduced the Si-H bonding strength considerably. These hydrogen rich compounds could have promising energy applications as they link to alternative hydrogen fuel technology. The carbide systems Li-C (A=Li,Ca,Mg) were studied using \emph{ab initio} and evolutionary algorithms at high pressures. At ambient pressure Li2C2 and CaC2 are known to contain C22- dumbbell anions and CaC2 is polymorphic. At elevated pressure both CaC2 and Li2C2 display polymorphism. At ambient pressure the Mg-C system contains several experimentally known phases, however, all known phases are shown to be metastable with respect to the pure elements Mg and C. First principle investigation of the configurational space of these compounds via evolutionary algorithms results in a variety of metastable and unique structures. The binary compounds ZnSb and ZnAs are II-V electron-poor semiconductors with interesting thermoelectric properties. They contain rhomboid rings composed of Zn2Sb2 (Zn2As2) with multi-centered covalent bonds which are in turn covalently bonded to other rings via two-centered, two-electron bonds. Ionicity was explored via Bader charge analysis and it appears that the low ionicity that these materials display is a necessary condition of their multicentered bonding. Both compounds were found to have narrow, indirect band gaps with multi-valley valence and conduction bands; which are important characteristics for high thermopower in thermoelectric materials. Future work is needed to analyze the lattice properties of the II-V CdSb-type systems, especially in order to find the origin of the extremely low thermal conductivity that these systems display.
ContributorsBenson, Daryn Eugene (Author) / Häussermann, Ulrich (Thesis advisor) / Shumway, John (Thesis advisor) / Chamberlin, Ralph (Committee member) / Sankey, Otto (Committee member) / Treacy, Mike (Committee member) / Arizona State University (Publisher)
Created2013
Description
In many respects, the current public child welfare system closely resembles that of over 100 years ago. Then, as well as now, nonprofit child welfare agencies are the critical providers of service delivery to vulnerable children and their families. Contemporary nonprofits, however, are confronted with social and fiscal pressures to conform to normative practices and behaviors of governmental and for-profit organizations. Simultaneously, these agencies may also feel compelled to behave in accordance with a nonprofit normative ethic. Yet, scholars and practitioners are often unaware of how these different forces may be shaping the practices of child welfare agencies and, the nonprofit sector in general. This multi-paper dissertation examines how managerial and organizational practices of child welfare nonprofits are influenced business, government, and other nonprofit organizations and the extent to which processes process of institutional isomorphism in child welfare nonprofits are happening. Data was collected from a national ample of 184 child welfare administrators to explore marketization practices, collaboration behaviors, and managerial priorities of these agencies. Multinomial logistic, ordered logistic, and ordinary least squares regression, and historical analysis help shed light on the contemporary practices of these agencies. The results reveal that these agency's behaviors are shaped by government control, influences from the business community, identification with a nonprofit mindset (i.e., nonprofitness), funding streams, and various other factors. One key finding is that identification with a nonprofit mindset encourages certain behaviors like collaboration with other nonprofits and placing greater importance on key managerial priorities, but it does not reduce the likelihood of adopting business management strategies. Another important finding is that government control and funding does not have as strong as an influence on child welfare nonprofits as expected; however, influence from the business community does strongly affect many of their practices. The implications of these findings are discussed for child welfare agencies and the nonprofit sector in general. The consequences of nonprofits operating similarly to business and government are considered.
ContributorsRobichau, Robbie Waters (Author) / Catlaw, Thomas (Thesis advisor) / Nahavandi, Afsaneh (Committee member) / Gustavsson, Nora (Committee member) / Wang, Lili (Committee member) / Arizona State University (Publisher)
Created2013
Description
In the United States, under the provisions set forth by a policy known as community benefit, nonprofit hospitals receive special tax exemptions from government in exchange for providing a wide range of health care services to the communities in which they are located. In recent years, nonprofit hospitals have claimed billions of dollars as community benefit justifying their tax-exempt status. However, growing criticism by numerous stakeholders has questioned the extent to which the level of community benefit claimed by nonprofit hospitals reflects the exemptions they receive. In addition, a dearth of research exists to understand the relationship between community benefit claims and the impact they have on improving the health of communities. In an effort to better understand the relationship between community benefit claims, tax status, and community health outcomes this study examines the community benefit policies of a nonprofit healthcare system representing hospitals in California, Nevada, and Arizona. It does so by reviewing materials produced by the system, her hospitals, vested stakeholders, and government that have shaped the development, implementation, and assessment of community benefit policy processes. Findings of the study suggest that the majority of nonprofit hospital community benefit claims are consumed by shortfalls reported between costs associated with providing care to Medicare and Medicaid patients and the compensation nonprofit hospitals receive from government. Results of the study also demonstrate that community benefit policies do positively impact the health of communities. However, future community benefit policies need to be refined to include measures that capture the magnitude of community health improvement if the relationship between policy and health outcomes is to be fully realized.
ContributorsMartz, Mark Patrick (Author) / Cayer, Joseph (Thesis advisor) / Glaser, Mark (Committee member) / Corley, Elizabeth (Committee member) / Arizona State University (Publisher)
Created2013