The complexity and broadening of competencies have led to a number of assessment frameworks that advocate for the use of rater judgment in direct observation of clinical performance. The degree to which these assessment processes produce scores that are valid, are therefore vitally dependent on a rater’s cognitive ability. A number of theories suggest that many of the cognitive structures needed to complete rating tasks are capacity limited and may therefore become a source of difficulty when rating demands exceed resources. This thesis explores the role of rating demands on the performance and behaviour of raters in the assessment of clinical competence and asks: in what way do rating demands associated with rating clinical performance affect rater performance and behaviour? I hypothesized that as rating demands increase, rating performance declines and raters engage in cognitive avoidance strategies in order to complete the task. I tested this hypothesis by manipulating intrinsic and extraneous sources of load for raters in the assessment of clinical performance. Results consistently demonstrated that intrinsic load, specifically broadening raters’ focus by increasing the number of dimensions to be considered simultaneously, negatively affected indicators of rating quality. However, extraneous demands failed to result in the same effect in 2 of 3 experiments. When we explored the cognitive strategies raters engage under high load conditions we learned of a number of strategies to reduce cognitive work, including idiosyncratically minimizing intrinsic demands (leading to poor inter-rater reliability) and active elimination of sources of extraneous load, explaining both findings. When we induced extraneous load in manner that could not be easily minimized by raters, we also found impairments in rater performance, specifically the provision of feedback. I conclude that rating demands, whether induced intrinsically or by extraneous sources, impair rater performance affecting both the utility of scores and the opportunity for learner development. Implications for health professions education and future directions are discussed. / Dissertation / Doctor of Philosophy (PhD)

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.

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

A human factors experiment was conducted to assess whether a reduction in noise at the ear would cause an improvement in speech intelligibility, an improvement in cognitive performance, and/or a reduction in subjective mental workload. Modified Rhyme Test (MRT) stimuli were used to determine intelligibility and specific tests within the Complex Cognitive Assessment Battery (CCAB) were used to assess cognitive performance. The tests chosen from the CCAB were: Tower Puzzle, Logical Relations, and Numbers and Words. These tests were chosen because of the specific set of cognitive functions that they measure which corresponded to command and control tasks. Participants performed the MRT and CCAB tests simultaneously in a 114 dBA noise environment at two speech levels, 83 dB (linear) and 96 dB (linear), using two communication microphones, Gentex Model 1453 and a prototype communication microphone developed by Adaptive Technologies Inc. (ATI). The noise used in the experiment was from a recording made inside a US Army Bradley Fighting Vehicle. Subjective mental workload was assessed using the NASA-TLX and Modified Cooper-Harper (MCH) immediately after the experiment. Results indicated that the communication microphone developed by ATI reduced the noise level at the ear better than the current Gentex microphone. However, the Gentex microphone produced significantly higher speech intelligibility scores at the 96 dB speech level. Cognitive performance scores significantly improved with increasing speech level for both communication microphones, with the ATI microphone having the advantage at 83 dB and the Gentex at 96 dB. The results also indicated that the main effects of speech level and communication microphone did not have an effect on subjective mental workload. A correlation analysis revealed that there was a positive relationship between the two workload measurement tools, indicating that either scale may be used to assess mental workload. Therefore, it was concluded that the MCH could have been used instead of the NASA-TLX, since the overall workload score was of interest. / Ph. D.

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.

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.

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_t}, such that random variables X_t 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.

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

Cloud Computing presents a novel way for businesses to procure their IT needs. Its elasticity and on-demand provisioning enables a shift from capital expenditures to operating expenses, giving businesses the technological agility they need to respond to an ever-changing marketplace. The rapid adoption of Cloud Computing, however, poses a unique challenge to Cloud providers—their already very large electricity bill and carbon footprint will get larger as they expand; managing both costs is therefore essential to their growth. This thesis squarely addresses the above challenge. Recognizing the presence of Cloud data centers in multiple locations and the differences in electricity price and emission intensity among these locations and over time, we develop an optimization framework that couples workload distribution with time-varying signals on electricity price and emission intensity for financial and environmental benefits. The framework is comprised of an optimization model, an aggregate cost function, and 6 scheduling heuristics. To evaluate cost savings, we run simulations with 5 data centers located across North America over a period of 81 days. We use historical data on electricity price, emission intensity, and workload collected from market operators and research data archives. We find that our framework can produce substantial cost savings, especially when workloads are distributed both geographically and temporally—up to 53.35% on electricity cost, or 29.13% on carbon cost, or 51.44% on electricity cost and 13.14% on carbon cost simultaneously.

Cette thèse engagée à partir des enjeux de la transformation du paysage international de l’éducation supérieure et ses implications au niveau local et national de l’organisation des universités. Basé dans une approche néo-rationaliste des interactions entre acteurs et les systèmes d’enseignement supérieure, le concept gigogne d’arènes académiques et les processus de couplage/découplage, l’analyse se focalise sur le cas d’étude du développement, implantation et ajustement d’un dispositif de calcul des services d’enseignant-chercheur. La méthodologie est basée sur une observation participante de longue durée, l’action-recherche et la méthode d’étude de cas. L’analyse quantitative relative à la transformation de la structure et de la performance des enseignants-chercheurs avec les accomplissements de l’université est combinée avec l’analyse qualitative de données collectées par des entretiens individuels et de groupes conduits avec des enseignants-chercheurs, des membres de la direction de l’université ainsi qu’avec des experts de l’enseignement supérieur malaisien et international. Les analyses conduites démontrent – au niveau de l’organisation universitaire – la capacité de négociation des académiques et du management par rapport à leurs rôles et conditions d’avancement de carrière est central dans l’instrumentation du dispositif de calcul des services. Au niveau national, les analyses soulignent la complémentarité entre institutions d’éducation supérieure privées et publiques. Au niveau international, les analyses soulignent la capacité d’ajustement du système universitaire et des politiques malaisiennes relatives à l’enseignement supérieur et à la recherche pour la régulation de leurs positions dans l’arène académique internationale. / This thesis is based on issues concerning the changing landscape of higher education globally and its implication at the local and national levels of the organization of universities. Drawn from the neo-rationalism perspective on the interactions between actors and higher education systems, the ‘gigogne’ concept of the academic arenas and coupling / decoupling processes, the analysis focuses on the case study of the development, implementation and adjustment of academic workload model. The methodology applied is based on long-term participant observation, action research and case study approaches. It is mixing quantitative analysis of the transformation of the academics’ performance and structure with the university’s achievement. On the other hand, this quantitative approach is complimented with the qualitative analysis of data gathered through formal interviews and focus groups, conducted with academics, senior management of the university and as well as experts of the higher education system in Malaysia and globally.Conclusions from the findings demonstrate – at the organizational level of the university - the capability of negotiation of the academics and senior management with regards to their roles and conditions of career advancement is central in the instrumentation of the academic workload system. At the national level, it highlights the complementary action between public and private higher education institutions. At the international level, it stresses on the capability of adjustment of the university organization system and the Malaysian higher education policy to redefine itself in regulating its position at the arenas of international bodies in higher education.