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- All Subjects: competition
- Creators: Berliner, David C.
- Resource Type: Text
Description
The earliest Eocene marked the appearance of the first North American euprimates (adapids, omomyids). Despite the fact that leading hypotheses assert that traits involved in food acquisition underlie euprimate origination and early diversification, the precise role that dietary competition played in establishing euprimates as successful members of mammalian communities is unclear. This is because the degree of niche overlap between euprimates and all likely mammalian dietary competitors ("the euprimate competitive guild") is unknown. This research determined which of three major competition hypotheses - non-competition, strong competition, and weak competition - characterized the late Paleocene-early Eocene euprimate competitive guild. Each of these hypotheses is defined by a unique temporal pattern of niche overlap between euprimates and their non-euprimate competitors, allowing an evaluation of the nature of dietary competitive interactions surrounding the earliest euprimates in North America. Dietary niches were reconstructed for taxa within the fossil euprimate competitive guild using molar morphological measures determined to discriminate dietary regimes in two extant mammalian guilds. The degree of dietary niche separation among taxa was then evaluated across a series of fossil samples from the Bighorn Basin, Wyoming just prior to, during, and after euprimate origination. Statistical overlap between each pair of euprimate and non-euprimate dietary niches was determined using modified multivariate pairwise comparisons using distances in a multidimensional principal component "niche" space. Results indicate that euprimate origination and diversification in North America was generally characterized by the absence of dietary competition. This lack of competition with non-euprimates is consistent with an increase in the abundance and diversity of euprimates during the early Eocene, signifying that the "success" of euprimates may not be the result of direct biotic interactions between euprimates and other mammals. An examination of the euprimate dietary niche itself determined that adapids and omomyids occupied distinct niches and did not engage in dietary competition during the early Eocene. Furthermore, changes in euprimate dietary niche size over time parallel major climatic shifts. Reconstructing how both biotic and abiotic mechanisms affected Eocene euprimates has the potential to enhance our understanding of these influences on modern primate communities.
ContributorsStroik, Laura (Author) / Schwart, Gary T (Thesis advisor) / Reed, Kaye E (Committee member) / Campisano, Christopher J (Committee member) / Gunnell, Gregg F. (Committee member) / Arizona State University (Publisher)
Created2014
Description
In competitive Taekwondo, Electronic Body Protectors (EBPs) are used to register hits made by players during sparring. EBPs are comprised of three main components: chest guard, foot sock, and headgear. This equipment interacts with each other through the use of magnets, electric sensors, transmitters, and a receiver. The receiver is connected to a computer programmed with software to process signals from the transmitter and determine whether or not a competitor scored a point. The current design of EBPs, however, have numerous shortcomings, including sensing false positives, failing to register hits, costing too much, and relying on human judgment. This thesis will thoroughly delineate the operation of the current EBPs used and discuss research performed in order to eliminate these weaknesses.
ContributorsSpell, Valerie Anne (Author) / Kozicki, Michael (Thesis director) / Kitchen, Jennifer (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
School choice reforms such as charter schools, vouchers, open enrollment, and private and public school tax credit donation programs have expanded throughout the United States over the past twenty years. Arizona’s long-standing public school choice system enrolls a higher percentage of public school students in charter schools than any state besides Washington D.C. A growing number of Arizona’s charter schools are managed by for-profit and nonprofit Education Management Organizations (EMOs). Advocates of school choice argue that free-market education approaches will make public schools competitive and nimble as parents’ choices place pressures on schools to improve or close. This, then, improves all schools: public, private, and charter. Critics are concerned that education markets produce segregation along racial and social class lines and inequalities in educational opportunities, because competition favors advantaged parents and children who can access resources. Private and for-profit schools may see it in their interest to exclude students who require more support. School choice programs, then, may further marginalize students who live in poverty, who receive special education services, and English language learners.
We do not fully understand how Arizona’s mature school choice system affects parents and other stakeholders in communities “on the ground.” That is, how are school policies understood and acted out? I used ethnographic methods to document and analyze the social, cultural, and political contexts and perspectives of stakeholders at one district public school and in its surrounding community, including its charter schools. I examined: (a) how stakeholders perceived and engaged with schools; (b) how stakeholders understood school policies, including school choice policies; and (c) what influenced families’ choices.
Findings highlight how most stakeholders supported district public schools. At the same time, some “walked the line” between choices that were good for their individual families and those they believed were good for public schools and society. Stakeholders imagined “community” and “accountability” in a range of ways, and they did not all have equal access to policy knowledge. Pressures related to parental accountability in the education market were apparent as stakeholders struggled to make, and sometimes revisit, their choices, creating a tenuous schooling environment for their families.
We do not fully understand how Arizona’s mature school choice system affects parents and other stakeholders in communities “on the ground.” That is, how are school policies understood and acted out? I used ethnographic methods to document and analyze the social, cultural, and political contexts and perspectives of stakeholders at one district public school and in its surrounding community, including its charter schools. I examined: (a) how stakeholders perceived and engaged with schools; (b) how stakeholders understood school policies, including school choice policies; and (c) what influenced families’ choices.
Findings highlight how most stakeholders supported district public schools. At the same time, some “walked the line” between choices that were good for their individual families and those they believed were good for public schools and society. Stakeholders imagined “community” and “accountability” in a range of ways, and they did not all have equal access to policy knowledge. Pressures related to parental accountability in the education market were apparent as stakeholders struggled to make, and sometimes revisit, their choices, creating a tenuous schooling environment for their families.
ContributorsPotterton, Amanda U (Author) / Powers, Jeanne M. (Thesis advisor) / Berliner, David C. (Committee member) / Fischman, Gustavo E. (Committee member) / Glass, Gene V (Committee member) / Arizona State University (Publisher)
Created2017