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- Genre: Masters Thesis
- Creators: Arizona State University
- Creators: Chakraborty, Bijeta
- Member of: ASU Electronic Theses and Dissertations
Description
The increase in obesity since the 1980's has been associated with fast-food consumption. In hopes that calorie labeling will be an effective tool to combat obesity, congress included a provision in the Patient Protection and Affordable Care Act of 2010 (ACA) that will require all restaurants with twenty or more locations to post calorie information for each menu item. Current research has provided mixed results regarding the effectiveness of calorie labeling, but overall seems to suggest that calorie labeling may only be effective among certain populations. In September, 2012 McDonald's began to post calorie labels on their menu boards before it was federally mandated under the ACA. This policy provided the opportunity to study the impact of calorie labeling on the purchasing behavior of McDonald's patrons. This cross-sectional study was designed to determine if self-perception of diet, self-perception of health, smoking, physical activity, fruit and vegetable intake, or knowledge of daily calorie requirements is associated with the likelihood of noticing or using calorie labels, or total calories purchased. In addition, relationships between noticing or using calorie labels with total calories purchased were also examined. Receipts and survey responses were collected from 330 participants who purchased food and beverage items from 27 different McDonald's locations within a 20 mile radius of downtown Phoenix, Arizona. Results indicated that only 16.1% of the sample reported using calorie labels, and those who reported using calorie labels purchased an average of 136 fewer calories. Multivariate analysis indicated there were no statistically significant relationships between self-perception of diet, self-perception of health, smoking, physical activity, fruit and vegetable intake, or knowledge of daily calorie requirements with the likelihood of noticing or using calorie labels, or total calories purchased. However, it is possible that the small sample size of participants using calorie labeling precluded any statistically significant relationships among these variables from emerging. Further research with larger sample sizes should be conducted, to investigate individual level factors that may be associated with use of calorie labeling.
ContributorsBrown, Alan (Author) / Ohri-Vachaspati, Punam (Thesis advisor) / Bruening, Meredith (Committee member) / Wharton, Christopher (Christopher Mack), 1977- (Committee member) / Arizona State University (Publisher)
Created2013
Description
Efficiency of components is an ever increasing area of importance to portable applications, where a finite battery means finite operating time. Higher efficiency devices need to be designed that don't compromise on the performance that the consumer has come to expect. Class D amplifiers deliver on the goal of increased efficiency, but at the cost of distortion. Class AB amplifiers have low efficiency, but high linearity. By modulating the supply voltage of a Class AB amplifier to make a Class H amplifier, the efficiency can increase while still maintaining the Class AB level of linearity. A 92dB Power Supply Rejection Ratio (PSRR) Class AB amplifier and a Class H amplifier were designed in a 0.24um process for portable audio applications. Using a multiphase buck converter increased the efficiency of the Class H amplifier while still maintaining a fast response time to respond to audio frequencies. The Class H amplifier had an efficiency above the Class AB amplifier by 5-7% from 5-30mW of output power without affecting the total harmonic distortion (THD) at the design specifications. The Class H amplifier design met all design specifications and showed performance comparable to the designed Class AB amplifier across 1kHz-20kHz and 0.01mW-30mW. The Class H design was able to output 30mW into 16Ohms without any increase in THD. This design shows that Class H amplifiers merit more research into their potential for increasing efficiency of audio amplifiers and that even simple designs can give significant increases in efficiency without compromising linearity.
ContributorsPeterson, Cory (Author) / Bakkaloglu, Bertan (Thesis advisor) / Barnaby, Hugh (Committee member) / Kiaei, Sayfe (Committee member) / Arizona State University (Publisher)
Created2013
Description
One hypothesis for the small size of insects relative to vertebrates, and the existence of giant fossil insects, is that atmospheric oxygen levels have constrained body sizes because oxygen delivery would be unable to match the needs of metabolically active tissues in larger insects. This study tested whether oxygen delivery becomes more challenging for larger insects by measuring the oxygen-sensitivity of flight metabolic rates and behavior during hovering for 11 different species of dragonflies that range in mass by an order of magnitude. Animals were flown in 7 different oxygen concentrations ranging from 30% to 2.5% to assess the sensitivity of their behavior and flight metabolic rates to oxygen. I also assessed the oxygen-sensitivity of flight in low-density air (nitrogen replaced with helium), to increase the metabolic demands of hovering flight. Lowered atmosphere densities did induce higher metabolic rates. Flight behaviors but not flight metabolic rates were highly oxygen-sensitive. A significant interaction between oxygen and mass was found for total flight time, with larger dragonflies varying flight time more in response to atmospheric oxygen. This study provides some support for the hypothesis that larger insects are more challenged in oxygen delivery, as predicted by the oxygen limitation hypothesis for insect gigantism in the Paleozoic.
ContributorsHenry, Joanna Randyl (Author) / Harrison, Jon F. (Thesis advisor) / Kaiser, Alexander (Committee member) / Rutowski, Ronald L (Committee member) / Arizona State University (Publisher)
Created2011
Description
Research on priming has shown that a stimulus can cause people to behave according to the stereotype held about the stimulus. Two experiments were conducted in which the effects of elderly priming were tested by use of a driving simulator. In both experiments, participants drove through a simulated world guided by either an elderly or a younger female voice. The voices told the participants where to make each of six turns. Both experiments yielded slower driving speeds in the elderly voice condition. The effect was universal regardless of implicit and explicit attitudes towards elderly people.
ContributorsFoster, L Bryant (Author) / Branaghan, Russell (Thesis advisor) / Becker, David (Committee member) / Cooke, Nancy J. (Committee member) / Arizona State University (Publisher)
Created2012
Description
Class D Amplifiers are widely used in portable systems such as mobile phones to achieve high efficiency. The demands of portable electronics for low power consumption to extend battery life and reduce heat dissipation mandate efficient, high-performance audio amplifiers. The high efficiency of Class D amplifiers (CDAs) makes them particularly attractive for portable applications. The Digital class D amplifier is an interesting solution to increase the efficiency of embedded systems. However, this solution is not good enough in terms of PWM stage linearity and power supply rejection. An efficient control is needed to correct the error sources in order to get a high fidelity sound quality in the whole audio range of frequencies. A fundamental analysis on various error sources due to non idealities in the power stage have been discussed here with key focus on Power supply perturbations driving the Power stage of a Class D Audio Amplifier. Two types of closed loop Digital Class D architecture for PSRR improvement have been proposed and modeled. Double sided uniform sampling modulation has been used. One of the architecture uses feedback around the power stage and the second architecture uses feedback into digital domain. Simulation & experimental results confirm that the closed loop PSRR & PS-IMD improve by around 30-40 dB and 25 dB respectively.
ContributorsChakraborty, Bijeta (Author) / Bakkaloglu, Bertan (Thesis advisor) / Garrity, Douglas (Committee member) / Ozev, Sule (Committee member) / Arizona State University (Publisher)
Created2012
Description
This study aimed to identify the emotional/affective sources of discrepancies between physical activity behavior and a widely used self-perception measure of physical activity motivation. Overweight women (body mass index [BMI] ≥ 25 kg/m2, 18-64 years of age; N=37) were recruited from Arizona State University community through flyers and online newsletters. Participants wore a SenseWear accelerometer for 6 nights and 7 days and followed their normal patterns of daily living. Participants then completed a single lab visit and verbally responded to questions from the Behavorial Regulation Exercise Questionnaire (BREQ-2) while being video and audio recorded. Captured emotional responses were evaluated with facial recognition software (Noldus FaceReader). Discrepancies between BREQ-2 responses and physical activity behavior were associated with happiness and sadness emotional responses extracted from the facial recognition software using regression-based analyses. Results indicated an association between monitored physical activities and captured emotional response - specifically sadness - and that as intensity in physical activity increases, motivation increases. Associations between happiness/sadness and physical activity were not observed for all intensities of physical activity. A marginally significant association was observed for amotivation and sedentary, light-intensity physical activity, and moderate-vigorous physical activity in the sample. This study demonstrates a proof-of-concept for the integration of an empirical evaluation of happiness and sadness emotional states into the relationship between physical activity motivation and behavior.
ContributorsBryant, Sarah (Author) / Buman, Matthew P (Thesis advisor) / Chisum, Jack W (Committee member) / Hekler, Eric (Committee member) / Arizona State University (Publisher)
Created2016
Description
In this thesis, a digital input class D audio amplifier system which has the ability
to reject the power supply noise and nonlinearly of the output stage is presented. The main digital class D feed-forward path is using the fully-digital sigma-delta PWM open loop topology. Feedback loop is used to suppress the power supply noise and harmonic distortions. The design is using global foundry 0.18um technology.
Based on simulation, the power supply rejection at 200Hz is about -49dB with
81dB dynamic range and -70dB THD+N. The full scale output power can reach as high as 27mW and still keep minimum -68dB THD+N. The system efficiency at full scale is about 82%.
to reject the power supply noise and nonlinearly of the output stage is presented. The main digital class D feed-forward path is using the fully-digital sigma-delta PWM open loop topology. Feedback loop is used to suppress the power supply noise and harmonic distortions. The design is using global foundry 0.18um technology.
Based on simulation, the power supply rejection at 200Hz is about -49dB with
81dB dynamic range and -70dB THD+N. The full scale output power can reach as high as 27mW and still keep minimum -68dB THD+N. The system efficiency at full scale is about 82%.
ContributorsBai, Jing (Author) / Bakkaloglu, Bertan (Thesis advisor) / Arizona State University (Publisher)
Created2015
Description
Loss aversion manifests as a decision bias in which avoiding losses is preferred over acquiring rewards and can drastically alter an individual’s decision-making by overweighting potential losses relative to gains of equal magnitude. Consequently, individuals may require greater positive compensation to offset potential losses, exhibit contradictory choice preferences, or even avoid the decision entirely; and this behavior may be ascribed to an over-reliance on automatic, unconscious (intuitive) judgments rather than initiating analytic reasoning more capable of objectively evaluating outcomes.
Religion (specifically Christianity) is the topic of focus, as preliminary evidence suggests an individual’s intuitive inclinations positively correlate with and predict religious beliefs. Moreover, self-reported religious beliefs significantly differed as a function of inducing either intuitive or reflective mindsets. Therefore, the purpose of this experiment was to test the hypothesis that religious participants will display significantly greater levels of loss aversion than nonreligious participants.
This hypothesis extends from a previous study relating large-scale cultural and religious differences with loss aversion. While their results revealed religious orthodoxy strongly influenced loss aversion, the parameters elicited may be less stable as only two lottery questions were asked and religion was determined by cultural demographics. This study used the same design, but with a total of ten lotteries and a more detailed investigation into individual religious factors.
While loss aversion coefficients replicated the overall behavioral effect (Median θ = 2.6), independent sample, Mann-Whitney U tests did not yield any significant differences between Christian and Nonreligious participants (p > 0.05); nor did any of the religious factors examined account for a significant amount of variability.
This study attempted to add to current knowledge by further conflating the relationship between religiosity and adaptive decision strategies susceptible to errant and inconsistent behavior. While the hypotheses were unsupported, a null finding is still important, and future research re-testing this association or introducing causational designs may prove more fruitful in understanding these complex relationships.
Religion (specifically Christianity) is the topic of focus, as preliminary evidence suggests an individual’s intuitive inclinations positively correlate with and predict religious beliefs. Moreover, self-reported religious beliefs significantly differed as a function of inducing either intuitive or reflective mindsets. Therefore, the purpose of this experiment was to test the hypothesis that religious participants will display significantly greater levels of loss aversion than nonreligious participants.
This hypothesis extends from a previous study relating large-scale cultural and religious differences with loss aversion. While their results revealed religious orthodoxy strongly influenced loss aversion, the parameters elicited may be less stable as only two lottery questions were asked and religion was determined by cultural demographics. This study used the same design, but with a total of ten lotteries and a more detailed investigation into individual religious factors.
While loss aversion coefficients replicated the overall behavioral effect (Median θ = 2.6), independent sample, Mann-Whitney U tests did not yield any significant differences between Christian and Nonreligious participants (p > 0.05); nor did any of the religious factors examined account for a significant amount of variability.
This study attempted to add to current knowledge by further conflating the relationship between religiosity and adaptive decision strategies susceptible to errant and inconsistent behavior. While the hypotheses were unsupported, a null finding is still important, and future research re-testing this association or introducing causational designs may prove more fruitful in understanding these complex relationships.
ContributorsHowatt, Brian (Author) / Robles-Sotelo, Elias (Thesis advisor) / Vargas, Perla (Committee member) / Neal, Tess (Committee member) / Arizona State University (Publisher)
Created2017
Description
This study explores aggression among siblings. Specifically, this study tests whether different types of aggression among siblings occur more or less frequently than toward friends and acquaintances. This study also examines whether sex differences in aggression between siblings resemble sex differences in aggression among friends and acquaintances. Results suggest that direct aggression occurs much more frequently among siblings than among friends and acquaintances, but that indirect aggression occurs far less frequently among siblings than among friends and acquaintances. In addition, the findings suggest that certain sex differences in aggression, such as males directly aggressing more often than females, are diminished when the aggression occurs between siblings. Both males and females report high levels of direct aggression toward their siblings.
ContributorsKirsch, Amanda Phyllis (Author) / Kenrick, Douglas T (Thesis advisor) / Varnum, Michael E W (Committee member) / Neuberg, Steven L (Committee member) / Arizona State University (Publisher)
Created2021
Description
The purpose of this thesis is to determine whether different types of narcissistic behavior are associated with different kinds of economic risk behavior. The thesis examines five published articles to establish whether the sub-classifications of narcissistic personality disorder (NPD) are significantly linked to economic risk behavior, broadly defined. The primary hypothesis states that different classifications of narcissistic behavior will be associated with different kinds of economic risk behavior. The paper finds, broadly, that different kinds of narcissistic behavior classifications are indeed associated with different kinds of economic risk behavior. Specifically, grandiose narcissism (GN) is associated with higher rates of risky gambling behavior; however, manifestations of vulnerable narcissism (VN) appear to play an integral role in the relationship. The paper also finds that both GN and VN are associated with higher rates of oniomania where mediating roles of impulsivity, materialism, and emptiness are present. The thesis concludes that addressing the issue of narcissism cannot be viewed through the lens of any unilateral perspective.
ContributorsYoung, Jessica Ann (Author) / Alozie, Nicholas (Thesis advisor) / Thomas, Kathy (Committee member) / Scheall, Scott (Committee member) / Arizona State University (Publisher)
Created2023