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Investigating Pilot Performance Using Mixed-Modality Simulated Data LinkLancaster, Jeff A. 19 April 2004 (has links)
Empirical studies of general aviation (GA) pilot performance are lacking, especially with respect to envisioned future requirements. Two research studies were conducted to evaluate human performance using new technologies. In the first study, ten participants completed the Modified Rhyme Test (MRT) in an effort to compare the intelligibility of two text-to-speech (TTS) engines (DECtalk and AT&T's Natural Voices) as presented in 85 dB(A) aircraft cockpit engine noise. Results indicated significant differences in intelligibility (p £ 0.05) between the two speech synthesizers across the tested speech-to-noise ratios (S/N) (i.e., −5 dB, -8 dB, and −11 dB S/N) with the AT&T engine resulting in superior intelligibility in all of the S/N. The AT&T product was therefore selected as the TTS engine for the second study.
In the second study, 16 visual flight rules (VFR) rated pilots were evaluated for their data link performance using a flight simulator (ELITE i-GATE) equipped with a mixed-modality simulated data link within one of two flight conditions. Data link modalities included textual, synthesized speech, digitized speech, and synthesized speech/textual combination. Flight conditions included VFR (unlimited ceiling, visibility) or marginal VFR (MVFR) flight conditions (clouds 2800 feet above ground level [AGL], three miles visibility). Evaluation focused on the time required accessing, understanding, and executing data link commands. Additional data were gathered to evaluate workload, situation awareness, and subjective preference.
Results indicated significant differences in pilot performance, mental workload, and situation awareness across the data link modalities and between flight conditions. Textual data link resulted in decreased performance while the other three data link conditions did not differ in performance. Workload evaluation indicated increased workload in the textual data link condition. Situation awareness (SA) measures indicated differences in perceived SA between flight conditions while objective SA measures differed across data link conditions.
Actual or potential applications of this research include guidance in the development of flight performance objectives for future GA systems. Other applications include guidance in the integration of automated voice technologies in the cockpit and/or in similar systems that present elevated levels of background noise during normal communications and auditory display operations. / Ph. D.
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Relationships Between Training Load Metrics and Injury in Collegiate Women's SoccerLacina, Michael Allen 25 November 2020 (has links)
Injury risk reduction is an ever-evolving topic within an athletic environment. Consequences from an injury include participation time loss, financial, social, and personal costs. Coaching and medical staff strive to reduce the risk through various manners. Training load monitoring is one method that is utilized in injury risk reduction through global positioning systems (GPS) with statistical modeling. The purpose of this study was to investigate the external loads for training sessions and competition in starters versus non-starters; to determine if there were control chart violations associated with sustained injuries; and to determine whether in-season injuries were associate with one or more control chart violations. NCAA Division I female soccer players were recruited during the fall 2019 season. Participants were provided a STATSports GPS unit to wear during all practice and competition sessions to analyze the following variables: total distance, high metabolic load distance, sprints, accelerations, decelerations, and dynamic stress load (DSL). These variables were analyzed using statistical process control charts (SPC Charts) and Nelson Rules. Overall, there were 1,235 violations for the team, with the highest amount coming from DSL. Throughout the season, there were 16 time-loss injuries. Within the 3- and 7-day periods prior to injury, there were only two cases in which the injured athlete had more violations when compared to the team average. Therefore, SPC Charts were not a good indicator of injury risk prediction within this population. Future research includes reassessing these methods within a larger population and for a longer duration (i.e. several seasons). / Master of Science / Reducing the risk of injury in athletes is a focal point for many coaches, training, and medical staffs in collegiate athletics. The consequences of injury range from loss of playing time to financial and long-term health costs. Being able to reduce the risk of injuries not only has personal implications for the athlete but also relates to overall team success. Using global positioning systems (GPS) to track the amount of work done in training can possibly reduce injury risk. This study planned to investigate the workload in NCAA Division 1 collegiate female soccer athletes and if any injuries were sustained during both training and competition settings. The results suggest that statistical process control (SPC) charts and the Nelson Rules did not predict injury risk within this population. There is limited research that has used these tools. Future work can reassess these methods within larger collegiate athletic populations, over a longer period of time.
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A stochastic process model for transient trace dataMathur, Anup 05 October 2007 (has links)
Creation of sufficiently accurate workload models of computer systems is a key step in evaluating and tuning these systems. Workload models for an observable system can be built from traces collected by observing the system.
This dissertation presents a novel technique to construct non-executable, artificial workload models fitting transient trace data. The trace can be a categorical or numerical time-series. The trace is considered a sample realization of a non-stationary stochastic process, {X<sub>t</sub>}, such that random variables X<sub>t</sub> follow different probability distributions. To estimate the parameters for the model a Rate Evolution Graph (REG) is built from the trace data. The REG is a two-dimensional Cartesian graph which plots the number of occurrences of each unique state in the trace on the ordinate and time on the abscissa. The REG contains one path for all instances of each unique state in the trace. The derivative of a REG path at time t is used as an estimate of the probability of occurrence of the corresponding state at t. We use piecewise linear regression to fit straight line segments to each REG path. The slopes of the line segments that fit a REG path estimate the time dependent probability of occurrence of the corresponding state. The estimates of occurrence probabilities of all unique states in the trace are used to construct a time-dependent joint probability mass function. The joint probability mass function is the representation of the Pzrecewise Independent Stochastic Process model for the trace. Two methods that assist to compact the model, while retaining accuracy, are also discussed. / Ph. D.
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A Study of Reading with A Handheld ComputerLee, Young Seok 25 August 2003 (has links)
As handheld computers are becoming powerful, portable and wireless, they have recently received considerable attention in education because their multi-functionality and mobility can be used for supporting learning activities in various manner. In spite of the potential in education, handheld computers have several limitations. One of the critical limitations is the small screen size. In an attempt to find factors affecting text readability on the small screen of handheld computers, this study, first, reviewed basic reading process and reading model, previous studies examining potential factors affecting text readability on a small handheld screen.
This study investigated the effect of screen orientation and margin on reading performance (reading speed and comprehension) and subjective impressions (ease of reading, mental workload and satisfaction) with a handheld computer. A 2x2 within-subject factorial design was conducted with 16 participants reading texts from a PDA (Compaq iPAQ 3850).
The results of this study indicated that neither screen orientation nor margin had a significant influence on objective reading performance and subjective impression. It was found that there were no prevailing preference of screen orientation and margin in reading texts from a handheld computer screen. It was also found that participants had a favorable reading experience with the handheld computers. Based on results of experiments and post-experiment questionnaire, a set of recommendations was developed to improve reading from small screens of handheld computers. / Master of Science
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Energy-Efficient Cloud Radio Access Networks by Cloud Based Workload Consolidation for 5GSigwele, Tshiamo, Alam, Atm S., Pillai, Prashant, Hu, Yim Fun 12 November 2016 (has links)
Yes / Next-generation cellular systems like fth generation (5G) is are expected to experience tremendous tra c growth. To accommodate such tra c demand, there is a need to increase the network capacity that eventually requires the
deployment of more base stations (BSs). Nevertheless, BSs are very expensive and consume a lot of energy. With growing complexity of signal processing, baseband units are now consuming a signi cant amount of energy.
As a result, cloud radio access networks (C-RAN) have been proposed as anenergy e cient (EE) architecture that leverages cloud computing technology where baseband processing is performed in the cloud. This paper proposes an energy reduction technique based on baseband workload consolidation using virtualized general purpose processors (GPPs) in the cloud. The rationale for the cloud based workload consolidation technique model is to switch o idle
baseband units (BBUs) to reduce the overall network energy consumption. The power consumption model for C-RAN is also formulated with considering radio side, fronthaul and BS cloud power consumption. Simulation results demonstrate that the proposed scheme achieves an enhanced energy performance compared to the existing distributed long term evolution (LTE) RAN system. The proposed scheme saves up to 80% of energy during low tra c periods and 12% during peak tra c periods compared to baseline LTE system. Moreover, the proposed scheme saves 38% of energy compared to the baseline system on a daily average.
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Alle man på däck : En kvalitativ studie om varför medarbetare väljer att stanna eller avsluta sin anställning inom den svenska Marinen / All men on deck : A qualitative study on why employees choose to stay or end their employment within the Swedish NavyLiljeqvist, Amanda January 2024 (has links)
Abstract The Swedish Armed Forces prioritize leadership, values, and employee satisfaction, aiming to create good conditions for career advancement and to foster diversity. However, despite recruitment efforts, significant personnel turnover continues, challenging the organization's ability to meet its own and parliamentary goals for capability and readiness. The purpose of this sociological study is to identify and analyze the circumstances that influence employees' decisions to stay or leave the organization within the navy. The methodology uses qualitative research with semi-structured interviews, selected for its ability to delve into social interactions and reveal nuanced perspectives. Semi-structured interviews provide flexibility while maintaining some structure, allowing for in-depth exploration of interviewees' thoughts and experiences. A thematic analysis is conducted to identify patterns and themes related to employment, motivation, organizational culture, leadership, and personal circumstances. The selection process ensures a diverse representation of former and current employees to capture a range of experiences and perspectives.Drawing upon the sociology of emotions, a field that underscores the centrality of emotions in social interactions, this study examines concepts such as trust, solidarity, and belonging. By integrating this theoretical framework with empirical research, a deeper comprehension of employees' decisions to stay or depart from the organization is achieved. Key findings from the study include insights into organizational belonging, trust, and leadership. Furthermore, the study explores the role of culture and emotional labor in shaping employees' sense of belonging. Additionally, the study explores interviewees' experiences in juggling family and personal life responsibilities and explores the impact of demands and workload on employee well-being.
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A memory-based load balancing technique for distributed web serversBennur, Harsha 01 January 1998 (has links)
No description available.
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Trauma as a predictive factory for performance under stressHughes, Ashley M. 01 January 2010 (has links)
Stress research has recently gained attention in the importance of adapting to life stressors as well as to temporary stressors created in a laboratory. Much attention has recently been paid to the influence of individual differences in their contribution to performance and adaptation to stressful situations. The contribution of individual differences ranges from personality characteristics such as extraversion and introversion, optimism or pessimism and even in some cases, clinical diagnoses. On the other hand, coping with traumatic stress and its potential long-term implication sparks much controversy in various fields of psychology. Certain views predict higher resilience to stress with the ability to rise above the occasion and triumph in spite of stress while other theories indicate a decline in productivity and an inability to cope with stress. The goal of the present study was to empirically examine the effect of long-term traumatic exposure on adaptation to stress. This project was designed to detect trauma and traumatic symptomology in a nonclinical sample. This was done in order to determine the effect of traumatic stress in an operational context. The premise for the research involves the complex interplay of encoding traumatic memories. It involves main theories of the traumatic memory argument and the trauma equivalency argument which subsequently argue for varying levels of prevalence for traumatic occurrences. The main implications investigated include the functionality of traumatized individuals under the stress of sustained attention in the maximal adaptability model in stress and performance research. In order to conduct the investigation of trauma and human adaptability in performance, there were considered 3 main groupings for traumatized individuals in accordance to their range of stressful experiences. All participants were asked to perform a sustained attention task. Seventy-five participants in the age range of 18-41 enrolled in the study through the Sona System website for class participation in their respective psychology classes. The investigation used measures of demographics, the Dissociative Experiences Scale, the Traumatic Events Questionnaire, the Posttraumatic Stress Disorder Checklist, the Dundee Stress State Questionnaire, Conner's Continuous Performance Task II, and the NASA Task Load Index to assess traumatic stress, subjective distress and workload as well as to impose stress through sustained attention. Results indicated that significant differences in measures of impulsiveness in traumatized individuals suggest a heightened awareness and hypervigilance in their reactivity to performance measures. Meanwhile, interactions in performance and gender suggest differences attributed to biological influence to the stress reaction. Gender differences, when isolated by male and female groups showed differences in omission, the absence of a correctly hit target, and hit rate for females while males exhibited more impact on attentional capacity. The pertinence of these findings maintain significant differences in the subjects included in this sample. However, the limitations of the research propose design and measurement strategy differences to further explore trauma's full and versatile impact in stress performance. Implications for this research extend to military optimization and selection as well as training methods. The findings of the project contribute to clinical intervention and understanding of trauma while expanding the literature and knowledge in the field of psychology.
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BURNOUT IN VETERAN PENNSYLVANIA MUSIC EDUCATORS: SYMPTOMS, CAUSES, AND PERCEIVED SOLUTIONSNoll, Kayla, 0009-0001-9437-3750 05 1900 (has links)
The purpose of this study was to identify which dimensions of burnout affect veteran Pennsylvania music educators, investigate factors currently contributing to their sense of burnout, seek recommendations on how to remedy or alleviate symptoms of burnout, and uncover any relationships between burnout and demographic information. A total of 223 certified Pennsylvania music educators participated in this study. Participants completed a 44-item survey consisting of questions regarding demographic information, the Maslach Burnout Inventory-Educators Survey (MBI-ES), perceived causes of burnout, and perceived solutions to help alleviate burnout. Participant MBI-ES scores were compared to normative scores and indicated that participants are experiencing higher levels of emotional exhaustion, but lower levels of depersonalization and a greater sense of personal accomplishment. Female participants, participants aged 20-29, and participants with 5-10 years experience indicated higher levels of burnout than other participants, and those who taught at multiple grade levels, choir, or in multiple content areas reported elevated levels of emotional exhaustion. Participants aged 61+ and those with 31+ years of experience reported the lowest levels of burnout. Unmanageable Workload was most frequently ranked “8- Most Significant Cause,” followed by Student Behavioral Issues and Lack of Administrative Support. Reduce Teaching Responsibilities/Classes was most frequently ranked “8-Most Effective Solution,” followed by Hire More Teachers and Increase Administrative Support for Teachers. Substantial changes at the organizational level are needed to help reduce burnout and create an environment that fosters music teacher job satisfaction and career longevity. / Music Education
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An Evaluation of the Teaching Loads of Teachers in the High Schools of TexasBlanton, Earle B. 08 1900 (has links)
The problem of this study is to determine the normal teaching load of teachers teaching in the various fields in certain selected high schools of Texas.
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