Matching Items (19)
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- Creators: Arizona State University
- Creators: Mann, Annika
- Member of: Theses and Dissertations
Description
Global climate change (GCC) is among the most important issues of the 21st century. Adaptation to and mitigation of climate change are some of the salient local and regional challenges scientists, decision makers, and the general public face today and will be in the near future. However, designed adaptation and mitigation strategies do not guarantee success in coping with global climate change. Despite the robust and convincing body for anthropogenic global climate change research and science there is still a significant gap between the recommendations provided by the scientific community and the actual actions by the public and policy makers. In order to design, implement, and generate sufficient public support for policies and planning interventions at the national and international level, it is necessary to have a good understanding of the public's perceptions regarding GCC. Based on survey research in nine countries, the purpose of this study is two-fold: First, to understand the nature of public perceptions of global climate change in different countries; and secondly to identi-fy perception factors which have a significant impact on the public's willingness to sup-port GCC policies or commit to behavioral changes to reduce GHG emissions. Factors such as trust in GCC information which need to be considered in future climate change communication efforts are also dealt with in this dissertation. This study has identified several aspects that need to be considered in future communication programs. GCC is characterized by high uncertainties, unfamiliar risks, and other characteristics of hazards which make personal connections, responsibility and engagement difficult. Communication efforts need to acknowledge these obstacles, build up trust and motivate the public to be more engaged in reducing GCC by emphasizing the multiple benefits of many policies outside of just reducing GCC. Levels of skepticism among the public towards the reality of GCC as well as the trustworthiness and sufficien-cy of the scientific findings varies by country. Thus, communicators need to be aware of their audience in order to decide how educational their program needs to be.
ContributorsHagen, Bjoern (Author) / Pijawka, David (Thesis advisor) / Brazel, Anthony (Committee member) / Chhetri, Netra (Committee member) / Guhathakurta, Subhrajit (Committee member) / Arizona State University (Publisher)
Created2013
Description
The primary function of the medium access control (MAC) protocol is managing access to a shared communication channel. From the viewpoint of transmitters, the MAC protocol determines each transmitter's persistence, the fraction of time it is permitted to spend transmitting. Schedule-based schemes implement stable persistences, achieving low variation in delay and throughput, and sometimes bounding maximum delay. However, they adapt slowly, if at all, to changes in the network. Contention-based schemes are agile, adapting quickly to changes in perceived contention, but suffer from short-term unfairness, large variations in packet delay, and poor performance at high load. The perfect MAC protocol, it seems, embodies the strengths of both contention- and schedule-based approaches while avoiding their weaknesses. This thesis culminates in the design of a Variable-Weight and Adaptive Topology Transparent (VWATT) MAC protocol. The design of VWATT first required answers for two questions: (1) If a node is equipped with schedules of different weights, which weight should it employ? (2) How is the node to compute the desired weight in a network lacking centralized control? The first question is answered by the Topology- and Load-Aware (TLA) allocation which defines target persistences that conform to both network topology and traffic load. Simulations show the TLA allocation to outperform IEEE 802.11, improving on the expectation and variation of delay, throughput, and drop rate. The second question is answered in the design of an Adaptive Topology- and Load-Aware Scheduled (ATLAS) MAC that computes the TLA allocation in a decentralized and adaptive manner. Simulation results show that ATLAS converges quickly on the TLA allocation, supporting highly dynamic networks. With these questions answered, a construction based on transversal designs is given for a variable-weight topology transparent schedule that allows nodes to dynamically and independently select weights to accommodate local topology and traffic load. The schedule maintains a guarantee on maximum delay when the maximum neighbourhood size is not too large. The schedule is integrated with the distributed computation of ATLAS to create VWATT. Simulations indicate that VWATT offers the stable performance characteristics of a scheduled MAC while adapting quickly to changes in topology and traffic load.
ContributorsLutz, Jonathan (Author) / Colbourn, Charles J (Thesis advisor) / Syrotiuk, Violet R. (Thesis advisor) / Konjevod, Goran (Committee member) / Lloyd, Errol L. (Committee member) / Arizona State University (Publisher)
Created2013
Description
This is a study of the plight of smallholder agriculture in Northwest Costa Rica. More specifically, this is the story of 689 rice farms, of an average size of 7.2 hectares and totaling just less than 5,300 hectares within the largest agricultural irrigation system in Central America. I was able to define the physical bounds of this study quite clearly, but one would be mistaken to think that this simplicity transfers to a search for rural development solutions in this case. Those solutions lie in the national and international politics that appear to have allowed a select few to pick winners and losers in Costa Rican agriculture in the face of global changes. In this research, I found that water scarcity among smallholder farms between 2006 and 2013 was the product of the adaptations of other, more powerful actors in 2002 to threats of Costa Rica's ratification of the Central American Free Trade Agreement. I demonstrate how the adaptations of these more powerful actors produced new risks for others, and how this ultimately prevented the rural development program from meeting its development goals. I reflect on my case study to draw conclusions about the different ways risks may emerge in rural development programs of this type. Then, I focus on the household level and show that determinants of successful adaptation to one type of global change risk may make farmers more vulnerable to other types, creating a "catch-22" among vulnerable farmers adapting to multiple global change risks. Finally, I define adaptation limits in smallholder rice farming in Northwest Costa Rica. I show that the abandonment of livelihood security and well-being, and of the unique "parcelaro" identities of rice farmers in this region define adaptation limits in this context.
ContributorsWarner, Benjamin (Author) / Childers, Daniel (Thesis advisor) / Eakin, Hallie (Committee member) / Abbott, Joshua (Committee member) / Wiek, Arnim (Committee member) / Arizona State University (Publisher)
Created2014
Description
This project explores the cultural identity of a refugee group named Meskhetian Turks, an ethnic group forced to relocate multiple times in their long history. Driven from their original homeland and scattered around Central Asia and Eastern Europe for decades, approximately 15,000 Meskhetian Turks have been granted refugee status by the American government in recent years. The focus of this study is a group of Meskhetian Turkish refugees in the Phoenix metropolitan area. This is a narrative study conducted through twelve open-ended in-depth interviews and researcher's observations within the community. The interview questions revolved around three aspects of Meskhetian cultural identity, which were represented in each research question. These aspects were: how Meskhetian Turks define their own culture; how they define their connection to Turkey and Turks; and how they define Americans, American culture and their place within the American society. The first research question resulted in three themes: history, preservation of culture, and sense of community. The second research question revealed two themes: Meskhetian Turk's ties to Turkey, and the group's relationship with and perception of Turks in the area. The final research question provided two themes: the group's adaptation to United States, and interviewees' observations regarding the American culture. Exploring these themes, and examining the connection between these aspects provided a complex and intertwined web of connections, which explain Meskhetian Turkish cultural identity. Meskhetian Turks' cultural self-definition, relation with the Turkish community, and perceptions of American culture are all inter-connected, which supports and furthers a dialectic approach to cultural studies. The study also contributes to refugee adaptation literature by examining cultural identity influences on the group's adaptation in the United States and offering insight and suggestions for improving the adaptation process.
ContributorsBilge, Hatice Nurhayat (Author) / Broome, Benjamin J. (Thesis advisor) / Martinez, Jacqueline (Committee member) / Margolis, Eric (Committee member) / Arizona State University (Publisher)
Created2012
Description
Family adaptation to child developmental disability is a dynamic transactional process that has yet to be tested in a longitudinal, rigorous fashion. In addition, although children with developmental delays frequently have behavior problems, not enough research has examined possible underlying mechanisms in the relation between child developmental delay, adaptation and behavior problems. In the current study, factor analysis examined how best to conceptualize the construct of family adaptation to developmental delay. Also, longitudinal growth curve modeling tested models in which child behavior problems mediated the relation between developmental risk and indices of family adaptation. Participants included 130 typically developing children and their families (Mental Development Index [MDI] > 85) and 104 children with developmental delays and their families (MDI < 85). Data were collected yearly between the ages of three and eight as part of a multi-site, longitudinal investigation examining the interrelations among children's developmental status, family processes, and the emergence of child psychopathology. Results of the current study indicated that adaptation is best conceptualized as a multi-index construct. Different aspects of adaptation changed in unique ways over time, with some facets of adaptation remaining stable while others fluctuated. Child internalizing and externalizing behavior problems were found to decrease over time for both children with developmental delays and typically developing children. Child behavior problems were also found to mediate the relation between developmental risk and family adaptation for over half of the mediation pathways. Significant mediation results indicated that children with developmental delays showed higher early levels of behavior problems, which in turn was associated with more maladaptive adaptation. These findings provide further evidence that families of children with developmental delays experience both positive and more challenging changes in their families over time. This study implies important next steps for research and clinical practice in the area of developmental disability.
ContributorsPedersen y Arbona, Anita (Author) / Crnic, Keith A (Thesis advisor) / Sandler, Irwin (Committee member) / Lemery, Kathryn (Committee member) / Enders, Craig (Committee member) / Arizona State University (Publisher)
Created2011
Description
Cognitive Radios (CR) are designed to dynamically reconfigure their transmission and/or reception parameters to utilize the bandwidth efficiently. With a rapidly fluctuating radio environment, spectrum management becomes crucial for cognitive radios. In a Cognitive Radio Ad Hoc Network (CRAHN) setting, the sensing and transmission times of the cognitive radio play a more important role because of the decentralized nature of the network. They have a direct impact on the throughput. Due to the tradeoff between throughput and the sensing time, finding optimal values for sensing time and transmission time is difficult. In this thesis, a method is proposed to improve the throughput of a CRAHN by dynamically changing the sensing and transmission times. To simulate the CRAHN setting, ns-2, the network simulator with an extension for CRAHN is used. The CRAHN extension module implements the required Primary User (PU) and Secondary User (SU) and other CR functionalities to simulate a realistic CRAHN scenario. First, this work presents a detailed analysis of various CR parameters, their interactions, their individual contributions to the throughput to understand how they affect the transmissions in the network. Based on the results of this analysis, changes to the system model in the CRAHN extension are proposed. Instantaneous throughput of the network is introduced in the new model, which helps to determine how the parameters should adapt based on the current throughput. Along with instantaneous throughput, checks are done for interference with the PUs and their transmission power, before modifying these CR parameters. Simulation results demonstrate that the throughput of the CRAHN with the adaptive sensing and transmission times is significantly higher as compared to that of non-adaptive parameters.
ContributorsBapat, Namrata Arun (Author) / Syrotiuk, Violet R. (Thesis advisor) / Ahn, Gail-Joon (Committee member) / Xue, Guoliang (Committee member) / Arizona State University (Publisher)
Created2012
Description
Female infertility can present a significant challenge to quality of life. To date, few, if any investigations have explored the process by which women adapt to premature ovarian insufficiency (POI), a specific type of infertility, over time. The current investigation proposed a bi-dimensional, multi-factor, model of adjustment characterized by the identification of six latent factors representing personal attributes (resilience resources and vulnerability), coping (adaptive and maladaptive) and outcomes (distress and wellbeing). Measures were collected over the period of one year; personal attributes were assessed at Time 1, coping at Time 2 and outcomes at Time 3. It was hypothesized that coping factors would mediate associations between personal attributes and outcomes. Confirmatory Factor Analysis (CFA), simple regressions and single mediator models were utilized to test study hypotheses. Overall, with the exception of coping, the factor structure was consistent with predictions. Two empirically derived coping factors, and a single standalone strategy, avoidance, emerged. The first factor, labeled "approach coping" was comprised of strategies directly addressing the experience of infertility. The second was comprised of strategies indicative of "letting go /moving on." Only avoidance significantly mediated the association between vulnerability and distress.
ContributorsDriscoll, Mary (Author) / Davis, Mary C. (Thesis advisor) / Aiken, Leona S. (Committee member) / Luecken, Linda J. (Committee member) / Zautra, Alex J. (Committee member) / Arizona State University (Publisher)
Created2011
Description
Perceptions of climate variability and change reflect local concerns and the actual impacts of climate phenomena on people's lives. Perceptions are the bases of people's decisions to act, and they determine what adaptive measures will be taken. But perceptions of climate may not always be aligned with scientific observations because they are influenced by socio-economic and ecological variables. To find sustainability solutions to climate-change challenges, researchers and policy makers need to understand people's perceptions so that they can account for likely responses. Being able to anticipate responses will increase decision-makers' capacities to create policies that support effective adaptation strategies. I analyzed Mexican maize farmers' perceptions of drought variability as a proxy for their perceptions of climate variability and change. I identified the factors that contribute to the perception of changing drought frequency among farmers in the states of Chiapas, Mexico, and Sinaloa. I conducted Chi-square tests and Logit regression analyses using data from a survey of 1092 maize-producing households in the three states. Results showed that indigenous identity, receipt of credits or loans, and maize-type planted were the variables that most strongly influenced perceptions of drought frequency. The results suggest that climate-adaptation policy will need to consider the social and institutional contexts of farmers' decision-making, as well as the agronomic options for smallholders in each state.
ContributorsRodríguez, Natalia (Author) / Eakin, Hallie (Thesis advisor) / Muneepeerakul, Rachata (Thesis advisor) / Manuel-Navarrete, David (Committee member) / Arizona State University (Publisher)
Created2015
DescriptionPresents a television script adaptation of Jane Austen's Persuasion, as well as a study of adaptive theory and processes and analysis of three adaptations of Jane Austen's Pride and Prejudice.
ContributorsLeone, Mary Katherine (Author) / Mann, Annika (Thesis director) / Luna, Ilana (Committee member) / Barrett, The Honors College (Contributor) / School of Humanities, Arts, and Cultural Studies (Contributor)
Created2014-05
Description
This paper focuses on feudalist structure and values within this system in George R. R. Martin's fantasy novel series A Song of Ice and Fire and Shakespeare's play King Richard the Third. The paper is structured into three arguments that focus on different characters from each work. The first argument is focused on Tyrion Lannister and Richard III's deformity, and how they violate feudalist values. This argument ultimately comes to the discussion of whether or not these characters are monstrous and by what values. The second argument is focused on Daenerys Targaryen and Margaret, discussing why both authors give these women a supernatural power. The authors give women these powers because they believe that women should have power. Martin argues that women need to remake the structure, while Shakespeare believes women can change their place in the structure through collective action. The last argument focuses on Petyr Baelish and Richard III, and how they both represent a chaos attacking feudalism. Petyr is a chaos that comes outside the system, exploiting the values of the system, while Richard is a chaos within the system because he violates feudal values, while trying to hold positions where he needs to embody feudalist value. The authors come to different conclusions of what is trying to take down feudalist structure and how this could be fixed. Martin finds feudalism cannot be fixed and that other systems are not much better because they still create violence. Shakespeare comes to the conclusion that feudalism cannot be fixed because people continue to violate its values, so a new system must be put in place.
ContributorsPittaro, James Vincent (Author) / Mann, Annika (Thesis director) / Kirsch, Sharon (Committee member) / Barrett, The Honors College (Contributor) / School of Social and Behavioral Sciences (Contributor) / School of Humanities, Arts, and Cultural Studies (Contributor)
Created2015-05