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- Creators: Arizona State University
Description
Following the implementation of federal immigration control measures in the 1990s, Arizona became the main point of entry for undocumented immigrants along the US border with Mexico in the early 2000s. Since then, reports have blamed human smuggling facilitators for the increase of undocumented immigration into the state and the apparent development of violent practices targeting the undocumented. However, little is known about the organization of the groups who work at facilitating the transit of undocumented immigrants along the US Mexico Border. Based on interviews and narratives present in legal files of smuggling cases prosecuted in Phoenix, Arizona, the present study provides an analysis of local human smuggling operations. It argues that far from being under the control of organized crime, smuggling is an income generating strategy of the poor that generates financial opportunities for community members in financial distress. The study, raises questions over smuggling's perceptions as violent and instead identifies smuggling-related violence as a reflection of the structural violence carried out by the state against immigrant communities through policing, surveillance and the consistent and systematic exercise of race-based policies.
ContributorsSanchez, Gabriella (Author) / Romero, Mary L (Thesis advisor) / Fonow, Mary Margaret (Committee member) / Tsuda, Takeyuki (Committee member) / Arizona State University (Publisher)
Created2011
Description
The ways in which human relationships are managed via language is a topic of particular interest in the area of sociolinguistics where work into the study of such topics as politeness, impoliteness, and rapport management have attempted to shed light on this phenomenon. This study examines two segments of extended discourse by President Alvaro Uribe of Colombia at the 2008 Summit of the Rio Group where he addressed a gathering of Rio Group members comprising heads of state from Latin American and Caribbean nations. Faced with serious accusations about his nation's military actions into Ecuador a few days before the meeting in question, Uribe engaged the group through two extended statements where he defended his government's actions. In these two segments of discourse Uribe changed his tone; it is this change that the present study attempts to describe in terms of modification to the effects of his discourse on the relationship between himself and the other interlocutors. To this end, an analysis is done classifying Uribe's utterances as polite, per Brown and Levinson's politeness model, and impolite, per Culpeper's impoliteness model. Additionally, Spencer Oatey's model of rapport management is used to classify Uribe's utterances according to their effect on the components of rapport. These classifications are examined alongside an analysis of factors related to rapport management such as frame, purpose of the exchange, and participants, for the purpose of understanding how these many factors work together to generate a changed effect to rapport. Of greatest significance in this study is the relationship between (im)politeness strategies and components of rapport. This dynamic provided an interesting way of examining (im)politeness in a new context, one that factored-in the effects of (im)politeness to the relationship between interlocutors. The study, as described above, showed that Uribe's change in tone was indeed a change to approach to rapport management characterized by an initial focus on the transactional and relational goals rapport component in the first of two segments, that then changed in the second part to a focus on face and association rights.
ContributorsBambaren, Anamaria (Author) / García Fernandez, Carmen (Thesis advisor) / Cerron-Palomino, Alvaro (Committee member) / Adams, Karen L. (Committee member) / Arizona State University (Publisher)
Created2011
Description
Counterinsurgency (COIN) is a long process that even great powers struggle with. Nevertheless, South Korea as a middle power was successful with COINs in Vietnam and Iraq. What were the drivers for the Republic of Korea (ROK) military's success? This dissertation maintains that the unusual nature of missions coupled with political/socio-cultural advantages are sufficient conditions for success of the middle power COIN. COIN missions are seen as unusual to middle powers. A rare mission stimulates military forces to fight harder because they recognize this mission as an opportunity to increase their national prestige. COIN mission success is also more probable for middle powers because their forces make the best of their country's political/socio-cultural advantages. The ROK military's COINs are optimal cases to test these hypotheses. The ROK military's COIN in Vietnam was an extremely rare mission, which increased its enthusiasm. This enthusiasm was converted into appropriate capabilities. By identifying battleground dynamics, the ROK forces initially chose an enemy-oriented approach based upon the method of company-led tactical base, and then later introduced a population-led method. South Korea's political/socio-cultural advantages also contributed to its military success in Vietnam. The Confucius culture that South Koreans and Vietnamese shared allowed the ROK forces to win the hearts and minds of the Vietnamese population. The mission in Iraq was also a rare and important one for national prestige. Accordingly, South Korean forces were equipped with pride and were enthusiastic about missions in Arbil. They changed their organization from a rigid one to a more flexible one by strengthening civil-military units. The ROK military possessed the ability to choose a population-centric approach. South Korea's political and cultural climate also served as an advantage to accomplish COIN in Iraq. The culture of Jung allowed ROK soldiers to sincerely help the local Iraqis. This project contributes to developing a theory of the middle power COIN. The findings also generate security policy implications of how to deal with contingent situations led by the collapse of the North Korean regime and how to redefine the ROK military strategy for the future.
ContributorsBan, Kil-Joo (Author) / Simon, Sheldon (Thesis advisor) / Gortzak, Yoav (Committee member) / Mackinnon, Stephen (Committee member) / Arizona State University (Publisher)
Created2011
Description
Microfluidics is the study of fluid flow at very small scales (micro -- one millionth of a meter) and is prevalent in many areas of science and engineering. Typical applications include lab-on-a-chip devices, microfluidic fuel cells, and DNA separation technologies. Many of these microfluidic devices rely on micron-resolution velocimetry measurements to improve microchannel design and characterize existing devices. Methods such as micro particle imaging velocimetry (microPIV) and micro particle tracking velocimetry (microPTV) are mature and established methods for characterization of steady 2D flow fields. Increasingly complex microdevices require techniques that measure unsteady and/or three dimensional velocity fields. This dissertation presents a method for three-dimensional velocimetry of unsteady microflows based on spinning disk confocal microscopy and depth scanning of a microvolume. High-speed 2D unsteady velocity fields are resolved by acquiring images of particle motion using a high-speed CMOS camera and confocal microscope. The confocal microscope spatially filters out of focus light using a rotating disk of pinholes placed in the imaging path, improving the ability of the system to resolve unsteady microPIV measurements by improving the image and correlation signal to noise ratio. For 3D3C measurements, a piezo-actuated objective positioner quickly scans the depth of the microvolume and collects 2D image slices, which are stacked into 3D images. Super resolution microPIV interrogates these 3D images using microPIV as a predictor field for tracking individual particles with microPTV. The 3D3C diagnostic is demonstrated by measuring a pressure driven flow in a three-dimensional expanding microchannel. The experimental velocimetry data acquired at 30 Hz with instantaneous spatial resolution of 4.5 by 4.5 by 4.5 microns agrees well with a computational model of the flow field. The technique allows for isosurface visualization of time resolved 3D3C particle motion and high spatial resolution velocity measurements without requiring a calibration step or reconstruction algorithms. Several applications are investigated, including 3D quantitative fluorescence imaging of isotachophoresis plugs advecting through a microchannel and the dynamics of reaction induced colloidal crystal deposition.
ContributorsKlein, Steven Adam (Author) / Posner, Jonathan D (Thesis advisor) / Adrian, Ronald (Committee member) / Chen, Kangping (Committee member) / Devasenathipathy, Shankar (Committee member) / Frakes, David (Committee member) / Arizona State University (Publisher)
Created2011
Description
Welfare recipients must engage in a specified number of hours of work-based activities. Work-based activities include providing childcare for others, enrolling to obtain a GED, participating in job clubs, and working for pay. Welfare recipients may choose to get a GED or participate in job clubs to improve their chances of finding employment. As some states require participation in job clubs to receive welfare benefits, this study examined the likelihood of job club participation by low-income females in states where job club participation is optional, not mandatory. Using data from a sample of 3,642 low-income mothers participating in the Survey of Income and Program Participation (SIPP), I explored the relationship between educational attainment and the probability of attending job club or searches in the past month. Sociodemographic and state-level characteristics were used to control for other factors in logistic regression models. Results show that low-income women with higher educational attainment were more likely to attend a job club. Other significant factors were marital status, metropolitan residence, number of children, number of family members, and state poverty rate. Policy implications suggest that attendees already have the necessary skills to obtain a job and time limits and enrollment caps may hinder the changes of the targeted population.
ContributorsYim, Gloria T (Author) / Hayford, Sarah (Thesis advisor) / Peck, Laura (Committee member) / Yabiku, Scott (Committee member) / Arizona State University (Publisher)
Created2011
Description
The Magnetoplasmadynamic (MPD) thruster is an electromagnetic thruster that produces a higher specific impulse than conventional chemical rockets and greater thrust densities than electrostatic thrusters, but the well-known operational limit---referred to as ``onset"---imposes a severe limitation efficiency and lifetime. This phenomenon is associated with large fluctuations in operating voltage, high rates of electrode erosion, and three-dimensional instabilities in the plasma flow-field which cannot be adequately represented by two-dimensional, axisymmetric models. Simulations of the Princeton Benchmark Thruster (PBT) were conducted using the three-dimensional version of the magnetohydrodynamic (MHD) code, MACH. Validation of the numerical model is partially achieved by comparison to equivalent simulations conducted using the well-established two-dimensional, axisymmetric version of MACH. Comparisons with available experimental data was subsequently performed to further validate the model and gain insights into the physical processes of MPD acceleration. Thrust, plasma voltage, and plasma flow-field predictions were calculated for the PBT operating with applied currents in the range $6.5kA < J < 23.25kA$ and mass-flow rates of $1g/s$, $3g/s$, and $6g/s$. Comparisons of performance characteristics between the two versions of the code show excellent agreement, indicating that MACH3 can be expected to be as predictive as MACH2 has demonstrated over multiple applications to MPD thrusters. Predicted thrust for operating conditions within the range which exhibited no symptoms of the onset phenomenon experimentally also showed agreement between MACH3 and experiment well within the experimental uncertainty. At operating conditions beyond such values , however, there is a discrepancy---up to $\sim20\%$---which implies that certain significant physical processes associated with onset are not currently being modeled. Such processes are also evident in the experimental total voltage data, as is evident by the characteristic ``voltage hash", but not present in predicted plasma voltage. Additionally, analysis of the predicted plasma flow-field shows no breakdown in azimuthal symmetry, which is expected to be associated with onset. This implies that perhaps certain physical processes are modeled by neither MACH2 nor MACH3; the latter indicating that such phenomenon may not be inherently three dimensional and related to the plasma---as suggested by other efforts---but rather a consequence of electrode material processes which have not been incorporated into the current models.
ContributorsParma, Brian (Author) / Mikellides, Pavlos G (Thesis advisor) / Squires, Kyle (Committee member) / Herrmann, Marcus (Committee member) / Arizona State University (Publisher)
Created2011
Description
ABSTRACT There is a body of literature--albeit largely from the UK and Australia--that examines the ways in which class and gender influence life course, including educational attainment; however, much of this literature offers explanations and analyses for why individuals choose the life course they do. By assuming a cause-effect relationship between class and gender and life course, these studies perpetuate the idea that life can be predicted and controlled. Such an approach implies there is but one way of viewing--or an "official reading" of--the experience of class and gender. This silences other readings. This study goes beneath these "interpretations" and explores the phenomenon of identity and identity making in women who grew up working-class. Included is an investigation into how these women recognize and participate in their own identity making, identifying the interpretations they created and apply to their experience and the ways in which they juxtapose their educative experience. Using semi-structured interview I interviewed 21 women with working-class habitués. The strategy of inquiry that corresponded best to the goal of this project was heuristics, a variant of empathetic phenomenology. Heuristics distinguishes itself by including the life experience of the researcher while still showing how different people may participate in an event in their lives and how these individuals may give it radically different meanings. This has two effects: (1) the researcher recognizes that their own life experience affects their interpretations of these stories and (2) it elucidates the researcher's own life as it relates to identity formation and educational experience. Two, heuristics encourages different ways of presenting findings through a variety of art forms meant to enhance the immediacy and impact of an experience rather than offer any explanation of it. As a result of the research, four themes essential to locating the experience of women who grew up working class were discovered: making, paying attention, taking care, and up. These themes have pedagogic significance as women with working-class habitués navigate from this social space: the downstream effect of which is how and what these women take up as education.
ContributorsDecker, Shannon Irene (Author) / Blumenfeld-Jones, Donald (Thesis advisor) / Richards-Young, Gillian (Committee member) / Sandlin, Jennifer (Committee member) / Arizona State University (Publisher)
Created2011
Description
Current economic conditions necessitate the extension of service lives for a variety of aerospace systems. As a result, there is an increased need for structural health management (SHM) systems to increase safety, extend life, reduce maintenance costs, and minimize downtime, lowering life cycle costs for these aging systems. The implementation of such a system requires a collaborative research effort in a variety of areas such as novel sensing techniques, robust algorithms for damage interrogation, high fidelity probabilistic progressive damage models, and hybrid residual life estimation models. This dissertation focuses on the sensing and damage estimation aspects of this multidisciplinary topic for application in metallic and composite material systems. The primary means of interrogating a structure in this work is through the use of Lamb wave propagation which works well for the thin structures used in aerospace applications. Piezoelectric transducers (PZTs) were selected for this application since they can be used as both sensors and actuators of guided waves. Placement of these transducers is an important issue in wave based approaches as Lamb waves are sensitive to changes in material properties, geometry, and boundary conditions which may obscure the presence of damage if they are not taken into account during sensor placement. The placement scheme proposed in this dissertation arranges piezoelectric transducers in a pitch-catch mode so the entire structure can be covered using a minimum number of sensors. The stress distribution of the structure is also considered so PZTs are placed in regions where they do not fail before the host structure. In order to process the data from these transducers, advanced signal processing techniques are employed to detect the presence of damage in complex structures. To provide a better estimate of the damage for accurate life estimation, machine learning techniques are used to classify the type of damage in the structure. A data structure analysis approach is used to reduce the amount of data collected and increase computational efficiency. In the case of low velocity impact damage, fiber Bragg grating (FBG) sensors were used with a nonlinear regression tool to reconstruct the loading at the impact site.
ContributorsCoelho, Clyde (Author) / Chattopadhyay, Aditi (Thesis advisor) / Dai, Lenore (Committee member) / Wu, Tong (Committee member) / Das, Santanu (Committee member) / Rajadas, John (Committee member) / Papandreou-Suppappola, Antonia (Committee member) / Arizona State University (Publisher)
Created2011
Description
Proponents of current educational reform initiatives emphasize strict accountability, the standardization of curriculum and pedagogy and the use of standardized tests to measure student learning and indicate teacher, administrator and school performance. As a result, professional learning communities have emerged as a platform for teachers to collaborate with one another in order to improve their teaching practices, increase student achievement and promote continuous school improvement. The primary purpose of this inquiry was to investigate how teachers respond to working in professional learning communities in which the discourses privilege the practice of regularly comparing evidence of students' learning and results. A second purpose was to raise questions about how the current focus on standardization, assessment and accountability impacts teachers, their interactions and relationships with one another, their teaching practices, and school culture. Participants in this qualitative, ethnographic inquiry included fifteen teachers working within Green School District (a pseudonym). Initial interviews were conducted with all teachers, and responses were categorized in a typology borrowed from Barone (2008). Data analysis involved attending to the behaviors and experiences of these teachers, and the meanings these teachers associated with those behaviors and events. Teachers of GSD responded differently to the various layers of expectations and pressures inherent in the policies and practices in education today. The experiences of the teachers from GSD confirm the body of research that illuminates the challenges and complexity of working in collaborative forms of professional development, situated within the present era of accountability. Looking through lenses privileged by critical theorists, this study examined important intended and unintended consequences inherent in the educational practices of standardization and accountability. The inquiry revealed that a focus on certain "results" and the demand to achieve short terms gains may impede the creation of successful, collaborative, professional learning communities.
ContributorsBenson, Karen (Author) / Barone, Thomas (Thesis advisor) / Berliner, David (Committee member) / Enz, Billie (Committee member) / Arizona State University (Publisher)
Created2011
Description
Process variations have become increasingly important for scaled technologies starting at 45nm. The increased variations are primarily due to random dopant fluctuations, line-edge roughness and oxide thickness fluctuation. These variations greatly impact all aspects of circuit performance and pose a grand challenge to future robust IC design. To improve robustness, efficient methodology is required that considers effect of variations in the design flow. Analyzing timing variability of complex circuits with HSPICE simulations is very time consuming. This thesis proposes an analytical model to predict variability in CMOS circuits that is quick and accurate. There are several analytical models to estimate nominal delay performance but very little work has been done to accurately model delay variability. The proposed model is comprehensive and estimates nominal delay and variability as a function of transistor width, load capacitance and transition time. First, models are developed for library gates and the accuracy of the models is verified with HSPICE simulations for 45nm and 32nm technology nodes. The difference between predicted and simulated σ/μ for the library gates is less than 1%. Next, the accuracy of the model for nominal delay is verified for larger circuits including ISCAS'85 benchmark circuits. The model predicted results are within 4% error of HSPICE simulated results and take a small fraction of the time, for 45nm technology. Delay variability is analyzed for various paths and it is observed that non-critical paths can become critical because of Vth variation. Variability on shortest paths show that rate of hold violations increase enormously with increasing Vth variation.
ContributorsGummalla, Samatha (Author) / Chakrabarti, Chaitali (Thesis advisor) / Cao, Yu (Thesis advisor) / Bakkaloglu, Bertan (Committee member) / Arizona State University (Publisher)
Created2011