Matching Items (43,917)
Description
In order to catch the smartest criminals in the world, digital forensics examiners need a means of collaborating and sharing information with each other and outside experts that is not prohibitively difficult. However, standard operating procedures and the rules of evidence generally disallow the use of the collaboration software and techniques that are currently available because they do not fully adhere to the dictated procedures for the handling, analysis, and disclosure of items relating to cases. The aim of this work is to conceive and design a framework that provides a completely new architecture that 1) can perform fundamental functions that are common and necessary to forensic analyses, and 2) is structured such that it is possible to include collaboration-facilitating components without changing the way users interact with the system sans collaboration. This framework is called the Collaborative Forensic Framework (CUFF). CUFF is constructed from four main components: Cuff Link, Storage, Web Interface, and Analysis Block. With the Cuff Link acting as a mediator between components, CUFF is flexible in both the method of deployment and the technologies used in implementation. The details of a realization of CUFF are given, which uses a combination of Java, the Google Web Toolkit, Django with Apache for a RESTful web service, and an Ubuntu Enterprise Cloud using Eucalyptus. The functionality of CUFF's components is demonstrated by the integration of an acquisition script designed for Android OS-based mobile devices that use the YAFFS2 file system. While this work has obvious application to examination labs which work under the mandate of judicial or investigative bodies, security officers at any organization would benefit from the improved ability to cooperate in electronic discovery efforts and internal investigations.
Contributors
Mabey, Michael Kent (Author) / Ahn, Gail-Joon (Thesis advisor) / Yau, Stephen S. (Committee member) / Huang, Dijiang (Committee member) / Arizona State University (Publisher)
Created
2011
Description
The sacred San Francisco Peaks in northern Arizona have been at the center of a series of land development controversies since the 1800s. Most recently, a controversy arose over a proposal by the ski area on the Peaks to use 100% reclaimed water to make artificial snow. The current state of the San Francisco Peaks controversy would benefit from a decision-making process that holds sustainability policy at its core. The first step towards a new sustainability-focused deliberative process regarding a complex issue like the San Francisco Peaks controversy requires understanding the issue's origins and the perspectives of the people involved in the issue. My thesis provides an historical analysis of the controversy and examines some of the laws and participatory mechanisms that have shaped the decision-making procedures and power structures from the 19th century to the early 21st century.
Contributors
Mahoney, Maren (Author) / Hirt, Paul W. (Thesis advisor) / Tsosie, Rebecca (Committee member) / White, Dave (Committee member) / Arizona State University (Publisher)
Created
2011
Description
Learning and transfer were investigated for a categorical structure in which relevant stimulus information could be mapped without loss from one modality to another. The category space was composed of three non-overlapping, linearly-separable categories. Each stimulus was composed of a sequence of on-off events that varied in duration and number of sub-events (complexity). Categories were learned visually, haptically, or auditorily, and transferred to the same or an alternate modality. The transfer set contained old, new, and prototype stimuli, and subjects made both classification and recognition judgments. The results showed an early learning advantage in the visual modality, with transfer performance varying among the conditions in both classification and recognition. In general, classification accuracy was highest for the category prototype, with false recognition of the category prototype higher in the cross-modality conditions. The results are discussed in terms of current theories in modality transfer, and shed preliminary light on categorical transfer of temporal stimuli.
Contributors
Ferguson, Ryan (Author) / Homa, Donald (Thesis advisor) / Goldinger, Stephen (Committee member) / Glenberg, Arthur (Committee member) / Arizona State University (Publisher)
Created
2011
Description
In the U.S., high-speed passenger rail has recently become an active political topic, with multiple corridors currently being considered through federal and state level initiatives. One frequently cited benefit of high-speed rail proposals is that they offer a transition to a more sustainable transportation system with reduced greenhouse gas emissions and fossil energy consumption. This study investigates the feasibility of high-speed rail development as a long-term greenhouse gas emission mitigation strategy while considering major uncertainties in the technological and operational characteristics of intercity travel. First, I develop a general model for evaluating the emissions impact of intercity travel modes. This model incorporates aspects of life-cycle assessment and technological forecasting. The model is then used to compare future scenarios of energy and greenhouse gas emissions associated with the development of high-speed rail and other intercity travel technologies. Three specific rail corridors are evaluated and policy guidelines are developed regarding the emissions impacts of these investments. The results suggest prioritizing high-speed rail investments on short, dense corridors with fewer stops. Likewise, less emphasis should be placed on larger investments that require long construction times due to risks associated with payback of embedded emissions as competing technology improves.
Contributors
Burgess, Edward (Author) / Williams, Eric (Thesis advisor) / Fink, Jonathan (Thesis advisor) / Yaro, Robert (Committee member) / Arizona State University (Publisher)
Created
2011
Description
This qualitative case study examines the rationales of the relationship between Arizona State University (ASU)--an American public research university--and Tecnologico de Monterrey (ITESM), a Mexican private not for profit research university. The focus of the study is to document the different meanings participants attached to the rationales of this international inter-university relationship. The conceptual framework draws from internationalization of higher education and interpretive policy analysis literature. Qualitative methodologies were utilized in both data collection and analysis. Data consisted of institutional policy documents, a ranking survey, and semi-structured interviews with faculty, administrators, and senior leadership from both universities. This study demonstrates that the rationales of the ASU-ITESM relationship are complex and dynamic. They have a function (e.g., declared, interpreted, enacted) and meanings attached (e.g., type, scope, and priority). Declared rationales were expressed in an ideal state in institutional policy. Those were interpreted by the participants according to their individual sense-making framework, thus becoming the interpreted rationales. Participants acted upon such understandings; these enacted rationales refer to the real rationales shaping the inter-university relationship. Findings also show there were three different categories of meanings participants attached to rationales, based on their type, scope and priority. In terms of type, rationales took the form of values, interests and needs, or expected benefits; they can also be academic, economic, political, or social/cultural. In scope, rationales are broad or specific addressing the relationship overall or specific initiatives within; they target individual, organizational, or societal levels. As for priority, participants interpreted and acted upon rationales with high, moderate or low importance influenced by their job position (e.g., faculty, administrators, senior leadership).
Contributors
Camacho Lizárraga, Mónica Irene (Author) / Ovando, Carlos J. (Thesis advisor) / Allison, Maria T. (Committee member) / Turner, Caroline S. (Committee member) / Arizona State University (Publisher)
Created
2011
Description
As a prelude to a study on the post-liquefaction properties and structure of soil, an investigation of ground freezing as an undisturbed sampling technique was conducted to investigate the ability of this sampling technique to preserve soil structure and properties. Freezing the ground is widely regarded as an appropriate technique to recover undisturbed samples of saturated cohesionless soil for laboratory testing, despite the fact that water increases in volume when frozen. The explanation generally given for the preservation of soil structure using the freezing technique was that, as long as the freezing front advanced uni-directionally, the expanding pore water is expelled ahead of the freezing front as the front advances. However, a literature review on the transition of water to ice shows that the volume of ice expands approximately nine percent after freezing, bringing into question the hypothesized mechanism and the ability of a frozen and then thawed specimen to retain the properties and structure of the soil in situ. Bench-top models were created by pluviation of sand. The soil in the model was then saturated and subsequently frozen. Freezing was accomplished using a pan filled with alcohol and dry ice placed on the surface of the sand layer to induce a unidirectional freezing front in the sample container. Coring was used to recover frozen samples from model containers. Recovered cores were then placed in a triaxial cell, thawed, and subjected to consolidated undrained loading. The stress-strain-strength behavior of the thawed cores was compared to the behavior of specimens created in a split mold by pluviation and then saturated and sheared without freezing and thawing. The laboratory testing provide insight to the impact of freezing and thawing on the properties of cohesionless soil.
Contributors
Katapa, Kanyembo (Author) / Kavazanjian, Edward (Thesis advisor) / Houston, Sandra (Committee member) / Zapata, Claudia (Committee member) / Arizona State University (Publisher)
Created
2011
Description
ABSTRACT With projections indicating that by the year 2025, one of every four K-12 students in the United States will be Latino, addressing the needs of Latino students is an important question for educators. This study approached this question through an analysis of the educational life histories, stories, of successful first generation Mexican-American college graduates to understand some of the factors which helped them succeed in college. I categorized the stories inductively into three themes: 1) stories of students and school, 2) stories of friends, family, and cultural communities, and 3) stories about race and politics. Participants' intellectual self-concept, both positive and negative, was to a great extent influenced by the messages they received from the educational system. Some of the participants took a traditional path from high school through college, while others took very indirect paths. The support that they received from special programs at the university as well as from their webs of support was crucial in their success. In addition, I found that race mattered when the participants transitioned from their majority Latino high schools to the majority white university as the participants told stories of navigating the cultural and racial dynamics of their status as college students. The participants in my study worked hard to achieve their college degrees. "It's hard" was a phrase often repeated by all participants; hard work was also a cultural value passed on by hard working parents and family members. Stories of luck, both good and bad, factored into their educational life histories. Collaborative programs between secondary school and the university were helpful in creating a transitional bridge for the participants as were culturally-based mentoring programs. The participants benefitted from the culturally-based support they received at the university and the cultural and emotional support of their families. The participants' stories highlight the importance of a race-conscious approach to college going; one which begins with race and builds cross-racial coalitions. This approach would benefit Latino students and, ultimately improve the college going experiences of all students.
Contributors
Sheffield, Martha Lynn (Author) / Powers, Jeanne M. (Thesis advisor) / Appleton, Nicholas (Committee member) / Fischman, Gustavo (Committee member) / Arizona State University (Publisher)
Created
2011
Description
The population of older adults and the percentage of people living in urban areas are both increasing in the U.S. Finding ways to enhance city-dwelling, older adults' social integration, cognitive vitality, and connectedness to nature were conceptualized as critical pathways to maximizing their subjective well-being (SWB) and overall health. Past research has found that gardening is associated with increased social contact and reduced risk of dementia, and that higher levels of social support, cognitive functioning, mindfulness, and connectedness to nature are positively related to various aspects of SWB. The present study was a pilot study to examine the feasibility of conducting a randomized, controlled trial of community gardening and to provide an initial assessment of a new intervention--"Mindful Community Gardening," or mindfulness training in the context of gardening. In addition, this study examined whether community gardening, with or without mindfulness training, enhanced SWB among older adults and increased social support, attention and mindfulness, and connectedness to nature. Fifty community-dwelling adults between the ages of 55 and 79 were randomly assigned to one of three groups: Traditional Community Gardening (TCG), Mindful Community Gardening (MCG), or Wait-List Control. The TCG and MCG arms each consisted of two groups of 7 to 10 participants meeting weekly for nine weeks. TCG involved typical gardening activities undertaken collaboratively. MCG involved the same, but with the addition of guided development of non-judgmental, present-focused awareness. There was a statistically significant increase in different aspects of mindfulness for the TCG and the MCG arms. The interventions did not measurably impact social support, attention, or connectedness to nature in this small, high functioning, pilot sample. Qualitative analysis of interview data from 12 participants in the TCG and MCG groups revealed that both groups helped some participants to better cope with adversity. It was concluded that it is feasible to conduct randomized, controlled trials of community gardening with urban older adults, and considerations for implementing such interventions are delineated.
Contributors
Okvat, Heather Audrey (Author) / Zautra, Alex J. (Thesis advisor) / Davis, Mary C. (Committee member) / Knopf, Richard C. (Committee member) / Okun, Morris A. (Committee member) / Arizona State University (Publisher)
Created
2011
Description
A full understanding of material behavior is important for the prediction of residual useful life of aerospace structures via computational modeling. In particular, the influence of rolling-induced anisotropy on fatigue properties has not been studied extensively and it is likely to have a meaningful effect. In this work, fatigue behavior of a wrought Al alloy (2024-T351) is studied using notched uniaxial samples with load axes along either the longitudinal or transverse direction, and center notched biaxial samples (cruciforms) with a uniaxial stress state of equivalent amplitude about the bore. Local composition and crystallography were quantified before testing using Energy Dispersive Spectroscopy and Electron Backscattering Diffraction. Interrupted fatigue testing at stresses close to yielding was performed on the samples to nucleate and propagate short cracks and nucleation sites were located and characterized using standard optical and Scanning Electron Microscopy. Results show that crack nucleation occurred due to fractured particles for longitudinal dogbone/cruciform samples; while transverse samples nucleated cracks by debonded and fractured particles. Change in crack nucleation mechanism is attributed to dimensional change of particles with respect to the material axes caused by global anisotropy. Crack nucleation from debonding reduced life till matrix fracture because debonded particles are sharper and generate matrix cracks sooner than their fractured counterparts. Longitudinal samples experienced multisite crack initiation because of reduced cross sectional areas of particles parallel to the loading direction. Conversely the favorable orientation of particles in transverse samples reduced instances of particle fracture eliminating multisite cracking and leading to increased fatigue life. Cyclic tests of cruciform samples showed that crack growth favors longitudinal and transverse directions with few instances of crack growth 45 degrees (diagonal) to the rolling direction. The diagonal crack growth is attributed to stronger influences of local anisotropy on crack nucleation. It was observed that majority of the time crack nucleation is governed by the mixed influences of global and local anisotropies. Measurements of crystal directions parallel to the load on main crack paths revealed directions clustered near the {110} planes and high index directions. This trend is attributed to environmental effects as a result of cyclic testing in air.
Contributors
Makaš, Admir (Author) / Peralta, Pedro D. (Thesis advisor) / Davidson, Joseph K. (Committee member) / Sieradzki, Karl (Committee member) / Arizona State University (Publisher)
Created
2011
Description
The objective of this work is to develop a Stop-Rotor Multimode UAV. This UAV is capable of vertical take-off and landing like a helicopter and can convert from a helicopter mode to an airplane mode in mid-flight. Thus, this UAV can hover as a helicopter and achieve high mission range of an airplane. The stop-rotor concept implies that in mid-flight the lift generating helicopter rotor stops and rotates the blades into airplane wings. The thrust in airplane mode is then provided by a pusher propeller. The aircraft configuration presents unique challenges in flight dynamics, modeling and control. In this thesis a mathematical model along with the design and simulations of a hover control will be presented. In addition, the discussion of the performance in fixed-wing flight, and the autopilot architecture of the UAV will be presented. Also presented, are some experimental "conversion" results where the Stop-Rotor aircraft was dropped from a hot air balloon and performed a successful conversion from helicopter to airplane mode.
Contributors
Vargas-Clara, Alvaro (Author) / Redkar, Sangram (Thesis advisor) / Macia, Narciso (Committee member) / Rajadas, John (Committee member) / Arizona State University (Publisher)
Created
2011