Matching Items (43,917)
Description
This study addresses the landscape connectivity pattern at two different scales. The county-level analysis aims to understand how urban ecosystem structure is likely to evolve in response to the proposed development plans in Maricopa County, Arizona. To identify the spatio-temporal land pattern change, six key landscape metrics were quantified in relative to the urban development scenarios based on the certainty of the proposed urban plans with different level of urban footprints. The effects of future development plans from municipalities on landscape connectivity were then analyzed in the scaled temporal and spatial frame to identify in which urban condition the connectivity value would most likely to decrease. The results demonstrated that tremendous amount of lands will be dedicated to future urbanization, and especially urban agricultural lands will be likely to be vulnerable. The metro-level analysis focuses on a group of species that represent urban desert landscape and have different degrees of fragmentation sensitivity and habitat type requirement. It hypothesizes that the urban habitat patch connectivity is impacted upon by urban density. Two underlying propositions were set: first, lower connectivity is predominant in areas with high urbanization cover; second, landscape connectivity will be impacted largely on the interfaces between urban, suburban, and rural areas. To test this, a GIS-based connectivity modeling was employed. The resultant change in connectivity values was examined for exploring the spatial relation to predefined spatial frames, such as urban, suburban, and rural zones of which boundaries were delineated by buffering method with two criteria of human population density and urban cover proportion. The study outcomes provide a practical guidance to minimize connectivity loss and degradation by informing planners with more optimal alternatives among various policy decisions and implementation. It also gives an inspiration for ecological landscape planning in urbanized or urbanizing regions which can ultimately leads urban landscape sustainability.
Contributors
Pak, So-hyŏn (Author) / Cook, Edward (Thesis advisor) / Crewe, Katherine (Committee member) / Wu, Jianguo (Jingle) (Committee member) / Arizona State University (Publisher)
Created
2011
Description
Arizona has an abundant solar resource and technologically mature systems are available to capture it, but solar energy systems are still considered to be an innovative technology. Adoption rates for solar and wind energy systems rise and fall with the political tides, and are relatively low in most rural areas in Arizona. This thesis tests the hypothesis that a consumer profile developed to characterize the adopters of renewable energy technology (RET) systems in rural Arizona is the same as the profile of other area residents who performed renovations, upgrades or additions to their homes. Residents of Santa Cruz and Cochise Counties who had obtained building permits to either install a solar or wind energy system or to perform a substantial renovation or upgrade to their home were surveyed to gather demographic, psychographic and behavioristic data. The data from 133 survey responses (76 from RET adopters and 57 from non-adopters) provided insights about their decisions regarding whether or not to adopt a RET system. The results, which are statistically significant at the 99% level of confidence, indicate that RET adopters had smaller households, were older and had higher education levels and greater income levels than the non-adopters. The research also provides answers to three related questions: First, are the energy conservation habits of RET adopters the same as those of non-adopters? Second, what were the sources of information consulted and the most important factors that motivated the decision to purchase a solar or wind energy system? And finally, are any of the factors which influenced the decision to live in a rural area in southeastern Arizona related to the decision to purchase a renewable energy system? The answers are provided, along with a series of recommendations that are designed to inform marketers and other promoters of RETs about how to utilize these results to help achieve their goals.
Contributors
Porter, Wayne Eliot (Author) / Reddy, T. Agami (Thesis advisor) / Pasqualetti, Martin (Committee member) / Larson, Kelli (Committee member) / Kennedy, Linda (Committee member) / Arizona State University (Publisher)
Created
2011
Description
Bridging semantic gap is one of the fundamental problems in multimedia computing and pattern recognition. The challenge of associating low-level signal with their high-level semantic interpretation is mainly due to the fact that semantics are often conveyed implicitly in a context, relying on interactions among multiple levels of concepts or low-level data entities. Also, additional domain knowledge may often be indispensable for uncovering the underlying semantics, but in most cases such domain knowledge is not readily available from the acquired media streams. Thus, making use of various types of contextual information and leveraging corresponding domain knowledge are vital for effectively associating high-level semantics with low-level signals with higher accuracies in multimedia computing problems. In this work, novel computational methods are explored and developed for incorporating contextual information/domain knowledge in different forms for multimedia computing and pattern recognition problems. Specifically, a novel Bayesian approach with statistical-sampling-based inference is proposed for incorporating a special type of domain knowledge, spatial prior for the underlying shapes; cross-modality correlations via Kernel Canonical Correlation Analysis is explored and the learnt space is then used for associating multimedia contents in different forms; model contextual information as a graph is leveraged for regulating interactions among high-level semantic concepts (e.g., category labels), low-level input signal (e.g., spatial/temporal structure). Four real-world applications, including visual-to-tactile face conversion, photo tag recommendation, wild web video classification and unconstrained consumer video summarization, are selected to demonstrate the effectiveness of the approaches. These applications range from classic research challenges to emerging tasks in multimedia computing. Results from experiments on large-scale real-world data with comparisons to other state-of-the-art methods and subjective evaluations with end users confirmed that the developed approaches exhibit salient advantages, suggesting that they are promising for leveraging contextual information/domain knowledge for a wide range of multimedia computing and pattern recognition problems.
Contributors
Wang, Zhesheng (Author) / Li, Baoxin (Thesis advisor) / Sundaram, Hari (Committee member) / Qian, Gang (Committee member) / Ye, Jieping (Committee member) / Arizona State University (Publisher)
Created
2011
Description
In the last few years, significant advances in nanofabrication have allowed tailoring of structures and materials at a molecular level enabling nanofabrication with precise control of dimensions and organization at molecular length scales, a development leading to significant advances in nanoscale systems. Although, the direction of progress seems to follow the path of microelectronics, the fundamental physics in a nanoscale system changes more rapidly compared to microelectronics, as the size scale is decreased. The changes in length, area, and volume ratios due to reduction in size alter the relative influence of various physical effects determining the overall operation of a system in unexpected ways. One such category of nanofluidic structures demonstrating unique ionic and molecular transport characteristics are nanopores. Nanopores derive their unique transport characteristics from the electrostatic interaction of nanopore surface charge with aqueous ionic solutions. In this doctoral research cylindrical nanopores, in single and array configuration, were fabricated in silicon-on-insulator (SOI) using a combination of electron beam lithography (EBL) and reactive ion etching (RIE). The fabrication method presented is compatible with standard semiconductor foundries and allows fabrication of nanopores with desired geometries and precise dimensional control, providing near ideal and isolated physical modeling systems to study ion transport at the nanometer level. Ion transport through nanopores was characterized by measuring ionic conductances of arrays of nanopores of various diameters for a wide range of concentration of aqueous hydrochloric acid (HCl) ionic solutions. Measured ionic conductances demonstrated two distinct regimes based on surface charge interactions at low ionic concentrations and nanopore geometry at high ionic concentrations. Field effect modulation of ion transport through nanopore arrays, in a fashion similar to semiconductor transistors, was also studied. Using ionic conductance measurements, it was shown that the concentration of ions in the nanopore volume was significantly changed when a gate voltage on nanopore arrays was applied, hence controlling their transport. Based on the ion transport results, single nanopores were used to demonstrate their application as nanoscale particle counters by using polystyrene nanobeads, monodispersed in aqueous HCl solutions of different molarities. Effects of field effect modulation on particle transition events were also demonstrated.
Contributors
Joshi, Punarvasu (Author) / Thornton, Trevor J (Thesis advisor) / Goryll, Michael (Thesis advisor) / Spanias, Andreas (Committee member) / Saraniti, Marco (Committee member) / Arizona State University (Publisher)
Created
2011
Description
Telomerase ribonucleoprotein is a unique reverse transcriptase that adds telomeric DNA repeats to chromosome ends. Telomerase RNA (TER) is extremely divergent in size, sequence and has to date only been identified in vertebrate, yeast, ciliate and plant species. Herein, the identification and characterization of TERs from an evolutionarily distinct group, filamentous fungi, is presented. Based on phylogenetic analysis of 69 TER sequences and mutagenesis analysis of in vitro reconstituted Neurospora telomerase, we discovered a conserved functional core in filamentous fungal TERs sharing homologous structural features with vertebrate TERs. This core contains the template-pseudoknot and P6/P6.1 domains, essential for enzymatic activity, which retain function in trans. The in vitro reconstituted Neurospora telomerase is highly processive, synthesizing canonical TTAGGG repeats. Similar to Schizosaccharomycetes pombe, filamentous fungal TERs utilize the spliceosomal splicing machinery for 3' processing. Neurospora telomerase, while associating with the Est1 protein in vivo, does not bind homologous Ku or Sm proteins found in both budding and fission yeast telomerase holoenzyme, suggesting a unique biogenesis pathway. The development of Neurospora as a model organism to study telomeres and telomerase may shed light upon the evolution of the canonical TTAGGG telomeric repeat and telomerase processivity within fungal species.
Contributors
Qi, Xiaodong (Author) / Chen, Julian (Thesis advisor) / Ghirlanda, Giovanna (Committee member) / Chaput, John (Committee member) / Arizona State University (Publisher)
Created
2011
Description
ABSTRACT This multi-case study research, using qualitative and quantitative methods, examines, compares, and validates the traits, behaviors, and formulas for success utilized by four experienced, long-term, exemplary executives who lead nonprofit organizations (NPOs) that serve homeless and "at risk" populations. Service longevity is a measure of success in this study and each leader subject must have served a minimum of five years at their NPO to participate, though most have been leading their respective NPOs far longer. An NPO leader affects not only an organization but individual constituents and the entire community. Each leader subject is considered successful by numerous constituents and the community. Anyone is at risk for homelessness and its effects on the entire community are boundless. Traits and formulas for success are measured using three surveys: Kouzes & Posner's 360 LPI and Most Admired Characteristics surveys and Cialdini's Influence IQ Test. Additional data sources are personal interviews, organizational 990s, annual reports, and other financial and programmatic data. The instruments for data analysis are a Likert 7 Point Importance Scale used for the program and organizational evaluations by NPO professional outside raters and the Strategic Plan. Analytic tools are the Pearson Product Moment Correlations, the organization's 990s, a 3 year annual report comparison, and participant observation. This study measures the leaders against the ideal. One common theme among all the leaders is consistency, one of Cialdini's Six Principles of Influence; ii
Contributors
Ostrom, Martha (Author) / Cayer, N. Joseph (Thesis advisor) / Cialdini, Robert B. (Committee member) / Schlacter, John L (Committee member) / Arizona State University (Publisher)
Created
2011
Description
Image processing in canals, rivers and other bodies of water has been a very important concern. This research using Image Processing was performed to obtain a photographic evidence of the data of the site which helps in monitoring the conditions of the water body and the surroundings. Images are captured using a digital camera and the images are stored onto a datalogger, these images are retrieved using a cellular/ satellite modem. A MATLAB program was designed to obtain the level of water by just entering the file name into to the program, a curve fit model was created to determine the contrast parameters. The contrast parameters were obtained using the data obtained from the gray scale image mainly the mean and variance of the intensity values. The enhanced images are used to determine the level of water by taking pixel intensity plots along the region of interest. The level of water obtained is accurate to less than 2% of the actual level of water observed from the image. High speed imaging in micro channels have various application in industrial field, medical field etc. In medical field it is tested by using blood samples. The experimental procedure proposed determines the flow duration and the defects observed in these channel using a fluid introduced into the micro channel the fluid being water based dye and whole milk. The viscosity of the fluid shows different types of flow patterns and defects in the micro channel. The defects observed vary from a small effect to the flow pattern to an extreme defect in the channel such as obstruction of flow or deformation in the channel. The sample needs to be further analyzed by SEM to get a better insight on the defects.
Contributors
Shasedhara, Abhijeet Bangalore (Author) / Lee, Taewoo (Thesis advisor) / Huang, Huei-Ping (Committee member) / Chen, Kangping (Committee member) / Arizona State University (Publisher)
Created
2011
Description
Extant evaluation studies of the Bayh-Dole Act of 1980 have focused primarily on its effects on the pace of innovation and on the norms and practices of academic research but neglected other public values. Seeking to redress this shortcoming, I begin by examining Bayh-Dole with respect to other relevant public values following the Public Value Failure approach. From that analysis, equity emerges as a pressing issue. I define equity issues, in a loosely Rawlsian sense, as situations of unfair distribution of political power and economic resources. My analysis identifies a business model of offices of technology transfer--that I call "nurturing start-ups"--that is likely to become a standard of practice. This model can foster either firm competition or concentration in emerging industries and will therefore have an impact on the distribution of economic benefits from innovation. In addition, political influence to reform Bayh-Dole is allocated disproportionately in favor of those who stand to gain from this policy. For instance, elite universities hold a larger share of the resources and voice of the university system. Consequently, adjusting the nurturing start-ups model to foster competition and increasing cooperation among universities should lead to a more equitable distribution of economic benefits and political voice in technology transfer. Conventional policy evaluation is also responsible for the neglect of equity considerations in Bayh-Dole studies. Currently, "what is the policy impact?" can be answered far more systematically than "why the impact matters?" or "is this policy designed and implemented legitimately?" The problem lies with the consequentialist theory of value that undergirds evaluation. Hence, I propose a deontological theory of evaluation to reaffirm the discipline's commitment to democratic policy making.
Contributors
Valdivia, Walter (Author) / Guston, David H. (Thesis advisor) / Sarewitz, Daniel (Committee member) / Bozeman, Barry (Committee member) / Arizona State University (Publisher)
Created
2011
Description
At its core, this dissertation is a study of how one group of ordinary people attempted to make change in their local and national community by reframing a public debate. Since 1993, over five thousand undocumented migrants have died, mostly of dehydration, while attempting to cross the US/Mexico border. Volunteers for No More Deaths (NMD), a humanitarian group in Tucson, hike the remote desert trails of the southern Arizona desert and provide food, water, and first aid to undocumented migrants in medical distress. They believe that their actions reduce suffering and deaths in the desert. On December 4, 2008, Walt Staton, a NMD volunteer placed multiple one-gallon jugs of water on a known migrant trail, and a Fish and Wildlife officer on the Buenos Aires National Wildlife Refuge near Arivaca, Arizona cited him for littering. Staton refused to pay the fine, believing that he was providing life-saving humanitarian aid, and was taken to court as a result. His trial from June 1-3, 2009 is the main focus of this dissertation. The dissertation begins by tracing the history of the rhetorical marker "illegal" and its role in the deaths of thousands of "illegal" immigrants. Then, it outlines the history of NMD, from its roots in the Sanctuary Movement to its current operation as a counterpublic discursively subverting the state. Next, it examines Staton's trial as a postmodern rhetorical situation, where subjects negotiate their rhetorical agency with the state. Finally, it measures the rhetorical effect of NMD's actions by tracing humanitarian and human rights ideographs in online discussion boards before and after Staton's sentencing. The study finds that despite situational restrictions, as the postmodern critique suggests, subjects are still able to identify and engage with rhetorical opportunities, and in doing so can still subvert the state.
Contributors
Accardi, Steven (Author) / Daly Goggin, Maureen (Thesis advisor) / Miller, Keith (Committee member) / Long, Elenore (Committee member) / Arizona State University (Publisher)
Created
2011
Description
Autism has a unique history. The definition has broadened and changed over time, from an emotional disturbance with psychogenic origins to a neurodevelopmental disability with suspected environmental and genetic origins. Diagnosis occurs later than children born with obvious disabilities such as cerebral palsy or Down syndrome, but earlier than milder, high-incidence disabilities such as dyslexia or attention deficit disorder. Historically, parents have advocated for changes in the way children with autism receive services and how federal funding and educational services are provided. There is often tension between these parents and the medical establishment. There can also be tension between the community of parents and the community of adults who have high functioning autism and Asperger syndrome. Studies have examined individual aspects of autism, from the diagnosis, caring for a child with autism, educational interventions, and genetics to characteristics of the internet community of adults with autism spectrum disorders (ASDs). This study includes interviews with mothers whose children were diagnosed with autism between 1974 and 2004, observations of appointments with developmental pediatricians at which diagnoses were given in 2010, and an analysis of media representations of autism over the same time period. These different data were analyzed together to create a new understanding about the history and present state of autism diagnosis.
Contributors
Hornstein, Shana (Author) / Swadener, Elizabeth (Thesis advisor) / Mathur, Sarup (Thesis advisor) / Cheatham, Gregory (Committee member) / Arizona State University (Publisher)
Created
2011