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The objective of this study was to investigate the generational differences among US commercial airline pilots regarding their attitudes toward safety. A survey was distributed to three different US airlines: one major commercial airline, one regional airline, and one charter airline. A total of 106 pilots participated in this study.

The objective of this study was to investigate the generational differences among US commercial airline pilots regarding their attitudes toward safety. A survey was distributed to three different US airlines: one major commercial airline, one regional airline, and one charter airline. A total of 106 pilots participated in this study. The pilots were categorized into three groups of generations based on birth years: Baby Boomers: 1946-1964, Generation X: 1965-1980, and Generation Y: 1981-2000. Through the use of one-way Analysis of Variance (ANOVA), the results of the analyses found that there was no significant difference between the generations of pilots regarding safety attitudes. In the subcategory of self-confidence, the results indicated no significant differences between the different generations of pilots. However, in the subcategories of risk orientation and safety orientation, significant differences were detected among the three generations of pilots. Baby Boomers were found to have the lowest risk tolerance, while Generation Y had the highest. Conversely, Baby Boomers were found to have the highest safety orientation, with the lowest being that of Generation Y.
ContributorsGashgari, Emad A (Author) / Niemczyk, Mary (Thesis advisor) / Nullmeyer, Robert (Committee member) / Gibbs, Robert (Committee member) / Arizona State University (Publisher)
Created2013
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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 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
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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

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
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Description
The Federal Flight Deck Officer (FFDO) program was mandated legislatively, as part of the Homeland Security Act of 2002. This study replicated earlier research that investigated pilots’ opinions of the current state of the FFDO program based on interviews. A Likert survey was created to allow simpler quantitative collection and

The Federal Flight Deck Officer (FFDO) program was mandated legislatively, as part of the Homeland Security Act of 2002. This study replicated earlier research that investigated pilots’ opinions of the current state of the FFDO program based on interviews. A Likert survey was created to allow simpler quantitative collection and analysis of opinions from large groups of pilots. A total of 43 airline pilots participated in this study. Responses to the Likert questions were compared with demographics, searching for significance through a Pearson chi-square test and frequencies were compared to earlier research findings. Significant chi-square results showed that those familiar with the program were more likely to agree the program should continue, it was effective, the screening and selection process of program applicants was adequate and the Federal Air Marshal Service’s management of the FFDO program was effective. Those with Military experience were more likely to disagree it was reasonable that FFDOs were required to pay for their own room and board during training or train on their own time. All those who shared an opinion agreed there should be a suggestion medium between FFDOs and their management. Unlike the prior study, all those familiar with the program agreed the weapons transportation and carriage procedures were adequate. Furthermore, all those who shared an opinion found the holster locking mechanism adequate, which was another reversal of opinion from the prior study. Similar to the prior study, pilots unanimously agree FFDOs were well trained and agreed that the program was effective and should continue.
ContributorsFerrara, Marc, M.S (Author) / Niemczyk, Mary (Thesis advisor) / Nullmeyer, Robert (Committee member) / Branaghan, Russell (Committee member) / Arizona State University (Publisher)
Created2017
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Description
Hypoxic hypoxia is a physiological condition which can manifest as a result of reduced barometric pressure, resulting in an insufficient amount of oxygen for use by the tissues in the body. Hypoxic hypoxia is of concern to pilots due to dangerous impairment the condition can cause in-flight, such as short

Hypoxic hypoxia is a physiological condition which can manifest as a result of reduced barometric pressure, resulting in an insufficient amount of oxygen for use by the tissues in the body. Hypoxic hypoxia is of concern to pilots due to dangerous impairment the condition can cause in-flight, such as short term memory loss, incoordination, or incapacitation. Several aircraft incidents and accidents have been attributed to hypoxia in the past ten years. To train for hypoxia recognition, high altitude chambers are used to induce hypoxia in participants, through a reduction of pressure inside a reinforced chamber. The training allows participants to experience their personal physiological symptoms of hypoxia in a controlled environment, in order to be trained in recognition and intervention techniques. This study surveyed 110 participants of high altitude chamber training to analyze perceptions, experience, and attitudes of respondents toward the training. Significant results were found; to include 99% of participants stating they would recommend the training to others, and 96.8% stating they felt they were a safer pilot, crewmember, or other support personnel due to attending high altitude chamber training. Two questions related to formal regulatory oversight revealed non-significant results. The purpose and results of this study are intended to support the improvement of aviation physiological training practices, in an effort to reduce hypoxia-related aircraft incidents an accidents in the future.
ContributorsStevenson, Kasey (Author) / Niemczyk, Mary (Thesis advisor) / Nullmeyer, Robert (Committee member) / Cline, Paul (Committee member) / Arizona State University (Publisher)
Created2019
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Description
This study was undertaken to ascertain to what degree, if any, virtual reality training was superior to monitor based training. By analyzing the results in a 2x3 ANOVA it was found that little difference in training resulted from using virtual reality or monitor interaction to facilitate training. The data did

This study was undertaken to ascertain to what degree, if any, virtual reality training was superior to monitor based training. By analyzing the results in a 2x3 ANOVA it was found that little difference in training resulted from using virtual reality or monitor interaction to facilitate training. The data did suggest that training involving rich textured environments might be more beneficial under virtual reality conditions, however nothing significant was found in the analysis. It might be possible that significance could be obtained by comparing a virtual reality set-up with higher fidelity to a monitor trial.
ContributorsWhitson, Richard (Author) / Gray, Robert (Thesis advisor) / Branaghan, Russell (Committee member) / Chiou, Erin (Committee member) / Arizona State University (Publisher)
Created2019
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Description
The purpose of this research was to determine if students who are enrolled in a professional flight program exhibit significantly higher rates of depression, stress, and anxiety. This study compared professional flight students to non-professional flight students to determine whether professional flight students have higher rates of depression and anxiety.

The purpose of this research was to determine if students who are enrolled in a professional flight program exhibit significantly higher rates of depression, stress, and anxiety. This study compared professional flight students to non-professional flight students to determine whether professional flight students have higher rates of depression and anxiety. In addition, this study sought to determine if there were higher depression, anxiety, and stress levels in upperclassmen (juniors and seniors) than in lowerclassmen (freshman and sophomore). Finally, upperclassmen and underclassmen within professional flight programs were compared to test if upperclassmen professional flight students exhibit higher rates for depression, anxiety and stress. These groups were compared to each other by using a survey that measures depression, anxiety, and stress. There were no statistically significant results. No singular group is more or less prone to depression, anxiety, or stress.
ContributorsJacobs, Destry (Author) / Niemczyk, Mary (Thesis advisor) / Cooke, Nancy J. (Thesis advisor) / Nullmeyer, Robert (Committee member) / Cline, Paul (Committee member) / Arizona State University (Publisher)
Created2019
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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

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%.
ContributorsBai, Jing (Author) / Bakkaloglu, Bertan (Thesis advisor) / Arizona State University (Publisher)
Created2015