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Title: HYSTERESIS EFFECTS IN DRIVING.
Creator: Morgan, Justin, Hancock, Peter, University of Central Florida
Abstract / Description: This dissertation presents two studies examining the interaction between workload history and driver mental workload. The first experiment focuses on testing for the presence of a hysteresis effect in the driving task. The second experiment examines the proposition that cueing impending periods of higher task demand can reduce the impact of any such potential hysteresis effects. Thirty-two licensed drivers served as participants and all served in both studies. Using the directions provided by...
Show moreThis dissertation presents two studies examining the interaction between workload history and driver mental workload. The first experiment focuses on testing for the presence of a hysteresis effect in the driving task. The second experiment examines the proposition that cueing impending periods of higher task demand can reduce the impact of any such potential hysteresis effects. Thirty-two licensed drivers served as participants and all served in both studies. Using the directions provided by a Heads-Up-Display navigation system, participants followed a pre-set route in the simulated environment. At specified points within the drive, the navigation system would purposefully fail which required drivers to relay a ten digit alphanumeric error code to a remote operator in order to reset the system. Results indicated that this increase in task demand from the navigation system's failure leads to a significant increase in perceived mental workload as compared to pre-failure periods. This increase in driver mental workload was not significantly reduced by the time the drive ended, indicating the presence of a hysteresis effect. In the second experiment, the navigation system provided a completely reliable visual warning before failure. Results indicate that cueing had neither an effect on perceived mental workload, nor any ameliorating effect on the hysteretic type effect seen in mental workload recovery. The conclusion of these findings being that the overall safety and efficiency of the surface transportation system would likely improve by designs which accommodate the periods immediately following a reduction in stress. Whether from leaving high demand areas such as work zones or in the period immediately after using a in-car information device such as a GPS or a cell phone, these post-high workload periods are associated with increased variability in driver inputs and levels of mental workload.
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Date Issued: 2008
Identifier: CFE0002169, ucf:47925
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002169

Title: Assessing the Effectiveness of Workload Measures in the Nuclear Domain.
Creator: Mercado, Joseph, Reinerman, Lauren, Hancock, Peter, Lackey, Stephanie, Szalma, James, University of Central Florida
Abstract / Description: An operator's performance and mental workload when interacting with a complex system, such as the main control room (MCR) of a nuclear power plant (NPP), are major concerns when seeking to accomplish safe and successful operations. The impact of performance on operator workload is one of the most widely researched areas in human factors science with over five hundred workload articles published since the 1960s (Brannick, Salas, (&) Prince, 1997; Meshkati (&) Hancock, 2011). Researchers have...
Show moreAn operator's performance and mental workload when interacting with a complex system, such as the main control room (MCR) of a nuclear power plant (NPP), are major concerns when seeking to accomplish safe and successful operations. The impact of performance on operator workload is one of the most widely researched areas in human factors science with over five hundred workload articles published since the 1960s (Brannick, Salas, (&) Prince, 1997; Meshkati (&) Hancock, 2011). Researchers have used specific workload measures across domains to assess the effects of taskload. However, research has not sufficiently assessed the psychometric properties, such as reliability, validity, and sensitivity, which delineates and limits the roles of these measures in workload assessment (Nygren, 1991). As a result, there is no sufficiently effective measure for indicating changes in workload for distinct tasks across multiple domains (Abich, 2013). Abich (2013) was the most recent to systematically test the subjective and objective workload measures for determining the universality and sensitivity of each alone or in combination. This systematic approach assessed taskload changes within three tasks in the context of a military intelligence, surveillance, and reconnaissance (ISR) missions. The purpose for the present experiment was to determine if certain workload measures are sufficiently effective across domains by taking the findings from one domain (military) and testing whether those results hold true in a different domain, that of nuclear. Results showed that only two measures (NASA-TLX frustration and fNIR) were sufficiently effective at indicating workload changes between the three task types in the nuclear domain, but many measures were statistically significant. The results of this research effort combined with the results from Abich (2013) highlight an alarming problem. The ability of subjective and physiological measures to indicate changes in workload varies across tasks (Abich, 2013) and across domain. A single measure is not able to measure the complex construct of workload across different tasks within the same domain or across domains. This research effort highlights the importance of proper methodology. As researchers, we have to identify the appropriate workload measure for all tasks regardless of the domain by investigating the effectiveness of each measure. The findings of the present study suggest that responsible science include evaluating workload measures before use, not relying on prior research or theory. In other words, results indicate that it is only acceptable to use a measure based on prior findings if research has tested that measure on the exact task and manipulations within that specific domain.
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Date Issued: 2014
Identifier: CFE0005666, ucf:50188
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005666

Title: STRESS, FATIGUE AND WORKLOAD: DETERMINING THE COMBINED AFFECT ON HUMAN PERFORMANCE.
Creator: Mock-McLaughlin, Jessica, Crumpton-Young, Lesia, University of Central Florida
Abstract / Description: This research generated a model that will help to predict, prevent, control and mitigate the occurrence of task related factors that negatively influence stress, fatigue, and workload; thus enhancing human performance. Past research efforts involving stress, fatigue and workload identified factors that influence a change in performance (Lan, Ji and Looney, 2003, and Hancock & Warm, 1989). Also, while some mathematical models have been developed within each respective area, however, there is...
Show moreThis research generated a model that will help to predict, prevent, control and mitigate the occurrence of task related factors that negatively influence stress, fatigue, and workload; thus enhancing human performance. Past research efforts involving stress, fatigue and workload identified factors that influence a change in performance (Lan, Ji and Looney, 2003, and Hancock & Warm, 1989). Also, while some mathematical models have been developed within each respective area, however, there is no evidence of an integrated model describing the combined affect of stress, fatigue and workload. To respond to this research gap, a quantitative model representing the state of stress, fatigue and workload experienced under task conditions was developed. This model was derived using fuzzy set theory with data inputs from both objective and subjective measures such as heart rate, NASA TLX, blood pressure and a variety of additional factors. The resultant mathematical model included both subjective and objective measures that can be collected in an occupational environment. Control rooms at the flight centers for large space craft were utilized to validate the quantitative model developed in this research. Data was gathered during launch simulation exercises. Fuzzy Set Theory was applied to develop the mathematical model to describe the changes in stress, fatigue and workload. FST provides a means to model many real-world environments.
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Date Issued: 2007
Identifier: CFE0001639, ucf:47231
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001639

Title: THE EFFECTS OF SECONDARY TASK DEMANDON THE ASSESSMENT OF THREAT.
Creator: Ganey, Harriss, Hancock, Peter, University of Central Florida
Abstract / Description: Threat perception is an important issue in today's world. As the line between hostile and non-hostile entities is blurred, it becomes more important for individuals to clearly distinguish between those who would present danger and those who would not. This series of experiments tested whether observers engaged in a dual-task paradigm perceived a greater amount of threat from target stimuli than they did when they were engaged in the threat task alone. The first experiment revealed that...
Show moreThreat perception is an important issue in today's world. As the line between hostile and non-hostile entities is blurred, it becomes more important for individuals to clearly distinguish between those who would present danger and those who would not. This series of experiments tested whether observers engaged in a dual-task paradigm perceived a greater amount of threat from target stimuli than they did when they were engaged in the threat task alone. The first experiment revealed that observers rated targets as more threatening when they were engaged in the additional task than when they only rated the targets themselves. Response time to the targets was also slower when a secondary task was present. This difference was more pronounced when the secondary task was presented via the auditory channel. Participants also rated overall workload higher when performing a secondary task, with the highest ratings being associated with the dual-task auditory condition. In the second experiment, the design crossed sensory modality with the presence or non-presence of threat. Inter-stimulus interval was also manipulated. The presence of threat was associated with faster response times, though when both tasks had threat components, response time was not the fastest. Additionally, when images came first in the stimulus pairs, observers were slower to respond to the first stimulus than when the sounds were presented first. Results supported the conclusion that additional task loading can affect the perception of threat. The modality of the additional task seems to also play a role in threat assessment performance. Results also led to the conclusion that threat-related visual stimuli are more challenging to process than threat-related auditory stimuli. Future research can now investigate how different types of tasks affect the threat perception task. Implications for better training of soldiers and for the design of automated systems are presented.
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Date Issued: 2006
Identifier: CFE0001156, ucf:46864
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001156

Title: EFFECTS OF INPUT MODALITY AND EXPERTISE ON WORKLOAD AND VIDEO GAME PERFORMANCE.
Creator: Kent, Travis, Sims, Valerie, University of Central Florida
Abstract / Description: A recent trend in consumer and military electronics has been to allow operators the option to control the system via novel control methods. The most prevalent and available form of these methods is that of vocal control. Vocal control allows for the control of a system by speaking commands rather than manually inputting them. This has not only implications for increased productivity but also optimizing safety, and assisting the disabled population. Past research has examined the potential...
Show moreA recent trend in consumer and military electronics has been to allow operators the option to control the system via novel control methods. The most prevalent and available form of these methods is that of vocal control. Vocal control allows for the control of a system by speaking commands rather than manually inputting them. This has not only implications for increased productivity but also optimizing safety, and assisting the disabled population. Past research has examined the potential costs and benefits to this novel control scheme with varying results. The purpose of this study was to further examine the relationship between modality of input, operator workload, and expertise. The results obtained indicated that vocal control may not be ideal in all situations as a method of input as participants experienced significantly higher amounts of workload than those in the manual condition. Additionally, expertise may be more specific than previously thought as participants in the vocal condition performed nearly identical at the task regardless of gaming expertise. The implications of the findings for this study suggest that vocal control be further examined as an effective method of user input, especially with regards to expertise and training effects.
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Date Issued: 2011
Identifier: CFH0004122, ucf:44877
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004122

Title: Examining Energetic and Structural Components of Knowledge of Result Using a Vigilance Paradigm.
Creator: Fraulini, Nicholas, Szalma, James, Mouloua, Mustapha, Hancock, Peter, Matthews, Gerald, University of Central Florida
Abstract / Description: Vigilance, or the ability to maintain attention to stimuli over a prolonged period of time (Davies (&) Parasuraman, 1982; Warm (&) Jerison, 1984), has been a troublesome research topic since World War II. Scientists have sought to counteract performance declines in vigilance tasks by training observers on these tasks. Though an extensive literature has been developed to examine the effectiveness of these techniques, the mechanisms by which many forms of vigilance training help performance are...
Show moreVigilance, or the ability to maintain attention to stimuli over a prolonged period of time (Davies (&) Parasuraman, 1982; Warm (&) Jerison, 1984), has been a troublesome research topic since World War II. Scientists have sought to counteract performance declines in vigilance tasks by training observers on these tasks. Though an extensive literature has been developed to examine the effectiveness of these techniques, the mechanisms by which many forms of vigilance training help performance are largely unknown. The present dissertation seeks to further the understanding of how two forms of training for vigilance, practice and knowledge of result, function to improve observers' ability to remain vigilant as time on task increases. In addition to understanding these forms of training, this dissertation seeks to develop a training protocol that would train observers for vigilance without adversely affecting their cognitive resources. Finally, this dissertation utilizes this new training protocol to examine the potential for transfer of training, which has been a question for vigilance researchers for decades. Results relating to these three research questions are presented, as well as a discussion of how these results may inform or influence vigilance research in the future.
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Date Issued: 2017
Identifier: CFE0006876, ucf:51746
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006876

Title: Understanding Human Performance and Social Presence: An Analysis of Vigilance and Social Facilitation.
Creator: Claypoole, Victoria, Szalma, James, Mouloua, Mustapha, Sims, Valerie, Hancock, Peter, Joseph, Dana, University of Central Florida
Abstract / Description: Social facilitation is characterized by improved performance on simple, or well-known, tasks and impaired performance on complex, or unfamiliar, tasks. Previous research has demonstrated that the use of social presence may improve performance on cognitive-based tasks that are relevant to many organizational contexts, such as vigilance. However, to date, there has not been consolidation of the research regarding the different implementations of social facilitation, or any analysis indicating...
Show moreSocial facilitation is characterized by improved performance on simple, or well-known, tasks and impaired performance on complex, or unfamiliar, tasks. Previous research has demonstrated that the use of social presence may improve performance on cognitive-based tasks that are relevant to many organizational contexts, such as vigilance. However, to date, there has not been consolidation of the research regarding the different implementations of social facilitation, or any analysis indicating which types of social presence are best under varying conditions. The present dissertation describes three experiments that seek to contribute to a taxonomic framework of social facilitation. Experiment One statistically established a difference in task difficulty between twoversions of a cognitive-based vigilance task by utilizing increasing increments of event rate in order to examine the first factor of the taxonomy (i.e., level of difficulty). Experiment Two explored the effects of two novel manipulations of social presence, electronic performance monitoring (i.e., EPM) and co-acting, in order to demonstrate that both novel forms of social presence could improve performance, and were worth examining further. Finally, ExperimentThree replicated and extended the results of Experiments One and Two by examining the interaction effects of levels of task difficulty and social presence through the use of ten conditions. Overall the results indicates that multiple forms of social presence can improve cognitive performance, however, this effect was not moderated by the level of task difficulty, as suggestedby the predominant theories of social facilitation. This suggests that future work should seek to replicate and extend this finding in order to determine if the level of task difficult is indeed a moderating variable of social facilitation. Additionally, the results demonstrated that social presence could be used in organizational settings in order to improve employee performance, while also sometimes reducing the perceived workload associated with the task.
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Date Issued: 2018
Identifier: CFE0006989, ucf:51631
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006989

Title: A COMPARISON OF ATTENTIONAL RESERVE CAPACITY ACROSS THREE SENSORY MODALITIES.
Creator: Brill, John, Gilson, Richard, University of Central Florida
Abstract / Description: There are two theoretical approaches to the nature of attentional resources. One proposes a single, flexible pool of cognitive resources; the other poses there are multiple resources. This study was designed to systematically examine whether there is evidence for multiple resource theory using a counting task consisting of visual, auditory, and tactile signals using two experiments. The goal of the first experiment was the validation of a multi-modal secondary loading task. Thirty-two...
Show moreThere are two theoretical approaches to the nature of attentional resources. One proposes a single, flexible pool of cognitive resources; the other poses there are multiple resources. This study was designed to systematically examine whether there is evidence for multiple resource theory using a counting task consisting of visual, auditory, and tactile signals using two experiments. The goal of the first experiment was the validation of a multi-modal secondary loading task. Thirty-two participants performed nine variations of a multi-modal counting task incorporating three modalities and three demand levels. Performance and subjective ratings of workload were measured for each of the nine conditions of the within-subjects design. Significant differences were found on the basis of task demand level, irrespective of modality. Moreover, the perceived workload associated with the tasks differed by task demand level and not by modality. These results suggest the counting task is a valid means of imposing task demands across multiple modalities. The second experiment used the same counting task as a secondary load to a primary visual monitoring task, the system monitoring component of the Multi-Attribute Task Battery (MATB). The experimental conditions consisted of performing the system monitoring task alone as a reference and performing system monitoring combined with visual, auditory, or tactile counting. Thirty-one participants were exposed to all four experimental conditions in a within-subjects design. Performance on the primary and secondary tasks was measured, and subjective workload was assessed for each condition. Participants were instructed to maintain performance on the primary task, irrespective of condition, which they did so effectively. Secondary task performance for the visual-auditory and visual-tactile conditions was significantly better than for the visual-visual dual task condition. Subjective workload ratings were also consistent with the performance measures. These results clearly indicate that there is less interference for cross-modal tasks than for intramodal tasks. These results add evidence to multiple resource theory. Finally, these results have practical implications that include human performance assessment for display and alarm development, assessment of attentional reserve capacity for adaptive automation systems, and training.
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Date Issued: 2007
Identifier: CFE0001660, ucf:47234
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001660

Title: EFFECT OF REPEATED FUNCTION ALLOCATION AND RELIABILITY ON AUTOMATION INDUCED MONITORING INEFFICIENCY.
Creator: Jones, Lauriann, Mouloua, Mustapha, University of Central Florida
Abstract / Description: The purpose of this study is to extend previous findings of Mouloua, Parasuraman, and Molloy (1993), Parasuraman, Mouloua, and Molloy (1996), Hilburn, Parasuraman, and Mouloua (1996), and Oakley, Mouloua, and Hancock (2003) by: 1) examining the effect of repeated adaptive function allocation to manual control of minimal length (5 minutes) to reduce of human error and minimize workload; 2) explore the placement or timing of adaptive function allocation intervals (approximately 20 minutes of...
Show moreThe purpose of this study is to extend previous findings of Mouloua, Parasuraman, and Molloy (1993), Parasuraman, Mouloua, and Molloy (1996), Hilburn, Parasuraman, and Mouloua (1996), and Oakley, Mouloua, and Hancock (2003) by: 1) examining the effect of repeated adaptive function allocation to manual control of minimal length (5 minutes) to reduce of human error and minimize workload; 2) explore the placement or timing of adaptive function allocation intervals (approximately 20 minutes of automation control to reduce the human operators' monitoring decrement between intervals, maintain adaptive recovery performance levels, and improve response times); 3) examine different levels of automation reliability (30%, 60%, and 90% reliable); 4) explore factors that may be manipulated to reduce automation-induced monitoring inefficiency, increase detection of automation malfunctions, improve situation awareness, reduce response/reaction times, and reduce workload in a simulated complex aviation system. The study was a 2 (non-adaptive control vs. adaptive group) x 3 (30%, 60%, and 90% automation reliability condition) x 4 (repeated 25 minute session) mixed factorial design. Fifty-four undergraduate participants' (i.e., 27 participants per group; 9 participants per condition; at least 18 yrs. of age) percentage of detected malfunctions, response times, and subjective workload were gathered from the Multi-Attribute Task Battery and the NASA TLX. Results indicated a significant improvement in detection of malfunctions and response times during adaptive-function allocation to manual control but without adaptive recovery. There was a significant effect for workload found between baseline measures and experimental sessions by group in the first session but not across experimental sessions. Theoretical and practical implications, limitations and future research are discussed.
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Date Issued: 2007
Identifier: CFE0001874, ucf:47387
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001874

Title: EFFECTS OF FLIGHT FACTORS ON PILOT PERFORMANCE, WORKLOAD, AND STRESS AT FINAL APPROACH TO LANDING PHASE OF FLIGHT.
Creator: Lee, Kyongsun, Lee, Gene, University of Central Florida
Abstract / Description: Since human errors are one of the major causes of flight accidents, the design and operation of the modern aircraft system deals with them seriously. Particularly, the pilot workload on aviation causes human errors. Whenever new procedures are introduced and operated, the aircraft capabilities have been checked in every aspect. However, there has been little study on the impact of the new procedures such as LDLP, SCDA, SATS, and Steep Angle approach on the pilot performance, workload, and...
Show moreSince human errors are one of the major causes of flight accidents, the design and operation of the modern aircraft system deals with them seriously. Particularly, the pilot workload on aviation causes human errors. Whenever new procedures are introduced and operated, the aircraft capabilities have been checked in every aspect. However, there has been little study on the impact of the new procedures such as LDLP, SCDA, SATS, and Steep Angle approach on the pilot performance, workload, and stress. In this study, different methods have been tried to understand the relationship between new procedures and the pilots in terms of performance, workload, and stress. The flight factors (e.g. flight experience, gliding angle, and approach area) were examined by the pilot performance, workload, and stress at the Ã‚Â"Final Approach to L/DÃ‚Â" phase using the single engine Cessna 172R type flight simulator. Five students and five instructor pilots from Embry-Riddle Aeronautical University in Dayton Beach, Florida, participated and they flew under four different simulation tasks of gliding angle and approach area. Their Heart Rate Variability (HRV) and NASA-Task Load Index (TLX) were measured to determine their stress level and subjective workload, respectively. In addition, Landing Performance (LP) data (e.g. landing distance, landing speed) and Above Glide Path Tracking Performance (AGPTP) data were also collected to evaluate pilot performance. As a result, the type of approach area showed a significant effect on pilot performance, workload, and stress determined by ANOVA (HRV, TLX, LP, AGPTP: all are p < .05). Flying over Ã‚Â"PopulatedÃ‚Â" area (e.g. a large city) resulted in lower pilot performance and higher pilot workload and stress than that over Ã‚Â"Non-PopulatedÃ‚Â" area (e.g. a grass field). Similarly, the levels of a gliding angle showed the statistical difference on the performance, workload, and stress (HRV, TLX, and LP: all are p < .05). During the flight with 4.5 degree, the pilots showed lower performance with higher workload and stress. However, the levels of the flight experience did not have any influence on the performance, workload, and stress levels (AGPTP, LP, TLX, HRV: all are p > .05). In conclusion, flying in Populated area and flying with a 4.5 degree gliding angle increases the workload and stress level of the pilots. In addition, when the pilots were flying over Populated area at Final Approach to L/D phase, they showed lower performance on tracking the glide path. Based on the results, stresses and workload can have a significant impact on flight performance. Therefore, in order to reduce the workload and stress that can cause human errors, it is highly recommended to carefully examine the impact of new flight procedures on pilot workload and stress before they are implemented.
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Date Issued: 2010
Identifier: CFE0003489, ucf:48937
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003489

Title: Comparing Types of Adaptive Automation within a Multi-Tasking Environment.
Creator: Taylor, Grant, Szalma, James, Hancock, Peter, Mouloua, Mustapha, Reinerman, Lauren, University of Central Florida
Abstract / Description: Throughout the many years of research examining the various effects of automation on operator performance, stress, workload, etc., the focus has traditionally been on the level of automation, and the invocation methods used to alter it. The goal of the current study is to instead examine the utilization of various types of automation with the goal of better meeting the operator's cognitive needs, thus improving their performance, workload, and stress. The task, control of a simulated unmanned...
Show moreThroughout the many years of research examining the various effects of automation on operator performance, stress, workload, etc., the focus has traditionally been on the level of automation, and the invocation methods used to alter it. The goal of the current study is to instead examine the utilization of various types of automation with the goal of better meeting the operator's cognitive needs, thus improving their performance, workload, and stress. The task, control of a simulated unmanned robotic system, is designed to specifically stress the operator's visual perception capabilities to a greater degree. Two types of automation are implemented to support the operator's performance of the task: an auditory beep aid intended to support visual perception resources, and a driving aid automating control of the vehicle's navigation, offloading physical action execution resources. Therefore, a comparison can be made between types of automation intended to specifically support the mental dimension that is under the greatest demand (the auditory beep) against those that do not (the driving automation). An additional evaluation is made to determine the benefit of adaptively adjusting the level of each type of automation based on the current level of task demand, as well as the influence of individual differences in personality.Results indicate that the use of the auditory beep aid does improve performance, but also increases Temporal Demand and Effort. Use of driving automation appears to disengage the operator from the task, eliciting a vigilance response. Adaptively altering the level of automation to meet task demands has a mixed effect on performance and workload (reducing both) when the auditory beep automation is used. However, adaptive driving automation is clearly detrimental, causing an increase in workload while decreasing performance. Higher levels of Neuroticism are related to poorer threat detection performance, but personality differences show no indication of moderating the effects of either of the experimental manipulations. The results of this study show that the type of automation implemented within an environment has a considerable impact on the operator, in terms of performance as well as cognitive/emotional state.
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Date Issued: 2012
Identifier: CFE0004340, ucf:49414
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004340

Title: Configural Displays: The effects of salience on multi-level data extraction.
Creator: Fok, Audrey, Mouloua, Mustapha, Hancock, Peter, Szalma, James, Pharmer, James, University of Central Florida
Abstract / Description: Displays are a useful tool for users and operators to understand information quickly. Configural displays are effective in supporting focus and divided attention tasks through the use of emergent features. Emergent features are highly salient and are generally used to support divided attention task However, due to the salience of emergent features, a potential performance costs to focused attention tasks arises with configural displays. To address this cost, semantic mapping has been used to...
Show moreDisplays are a useful tool for users and operators to understand information quickly. Configural displays are effective in supporting focus and divided attention tasks through the use of emergent features. Emergent features are highly salient and are generally used to support divided attention task However, due to the salience of emergent features, a potential performance costs to focused attention tasks arises with configural displays. To address this cost, semantic mapping has been used to map salience techniques to information needed by focus attention tasks to increase their saliency (Bennett (&) Walters, 2001; Bennett et al., 2000). Semantic mapping is the process of mapping the domain constrains to the display, which in turn is mapped to the users capabilities and limitations to understand that domain data. The objective of this dissertation is to extend the use of semantic mapping to address potential performance costs of configural displays for hierarchical domains using the scenario-based training (SBT) instructor domain. Two studies were conducted to examine the effects of salience application and salience type on data extraction accuracy and response time performances at low-level, mid-level, high-level, and a remediation task. The first study examined the effects of one salience technique mapped to the display. This study employed a 2(low or mid application) X 3(baseline, color techniques, and alphanumeric techniques) mixed model design in which 63 participants completed 3 blocks of 32 trails each using displays with the salience techniques mapped to either low- or mid-level data. Results from the first study showed that salience type had a significant impact on multi-level data extraction performance, but interactions were not found. The second study changed the manipulation of application and mapped two salience techniques display at the same time, using either the same technique or a combination of different techniques. The same experimental design was utilized and 65 participants completed study 2. Results of study 2 showed that different application resulted in greater improvements of performance and specific salience combinations were found better support data extraction performance. Across study analyses were also performed and revealed that more salience is not better than less salience. Instead it is the specific mapping of salience type and application which improves performance the most. Overall, these findings have major implications for theories of semantic mapping, attention and performance, and display design of hierarchical domains.
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Date Issued: 2015
Identifier: CFE0005947, ucf:50797
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005947

Title: Interactive Amusement Park Queues: Examining the Indirect Effect of Task Work Load on Guests' Perception of Wait Duration Through Task Immersion.
Creator: Ledbetter, Jonathan, Smither, Janan, Hancock, Peter, Joseph, Dana, Sims, Valerie, Allen, Robert, University of Central Florida
Abstract / Description: With the increasing attendance across amusement and theme parks worldwide, it is not surprising that minimizing the impact of large crowds and long attraction waits on the guests' experience has received much focus by park operators in recent years. Although effective in the short term, attempting to eliminate or reduce wait times by simply increasing capacity cannot be sustained long term. A recent trend in amusement park design is to theme the queue with interactive elements to engage...
Show moreWith the increasing attendance across amusement and theme parks worldwide, it is not surprising that minimizing the impact of large crowds and long attraction waits on the guests' experience has received much focus by park operators in recent years. Although effective in the short term, attempting to eliminate or reduce wait times by simply increasing capacity cannot be sustained long term. A recent trend in amusement park design is to theme the queue with interactive elements to engage guests and occupy their wait time with the intent of making the wait queue part of the attraction itself. Much of the research on the topic of waiting in line focuses on improving the customers' experience while waiting by altering the wait queue. Very little research to date empirically tests the impact that queue characteristics have on a customers' perceived wait duration with the research pool void of any applications to an interactive amusement park queue. This dissertation study tested five hypotheses to determine how playing an interactive math skills game while waiting to ride a virtual roller coaster affected the participants' perceived wait duration. The first hypothesis tested if the participants' perceived wait time decreased as the mental workload of the game increased. The results did not find that this effect of mental workload on perception of time was significant. The second hypothesis tested whether participants who experience higher levels of game immersion estimate perceive wait time to be lower. The results indicated that this effect of game immersion on perceived wait time was significant. The third hypothesis tested whether participants' experience higher levels of game immersion when the perceived mental workload of the math skills game was higher. This effect of mental workload on immersion was found to be significant.Hypothesis 4 tested whether the participants' perceived wait time was indirectly effected by the mental workload of the math skills through immersion. This indirect effect was found to be significant and the results support complete mediation by immersion because the direct effect was not significant with the indirect effect in the model. Hypothesis tested whether the mediated effect of mental workload on time perception via game immersion was moderated by participants' levels of sensation seeking and extraversion. Individual differences of extraversion and sensation seeking were not found to moderate the indirect effect.This study demonstrates that research in the area of time perception can be applied to amusement and theme park queue design. Furthermore, it shows the importance of providing guests with an immersive queue experience to positively impact their perception of wait time, the number one complaint of many amusement and theme park visitors. Future research in this field should examine the individual elements of the queue environment to determine the optimal design to increase the level of immersion for park guests.
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Date Issued: 2016
Identifier: CFE0006135, ucf:51183
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006135

Title: PREDICTING COGNITIVE WORKLOAD WITH MEASURES FROM FUNCTIONAL NEAR-INFRARED SPECTROSCOPY (FNIRS) AND HEART RATE.
Creator: Duany, John, Bohil, Corey, University of Central Florida
Abstract / Description: The objective of this study was to assess low to high levels of Cognitive Workload by measuring heart rate and cortical blood flow in real-time. Four conditions were implemented into a within-subjects experimental design. Two conditions of difficulty and two conditions of trial order were used to illicit different levels of workload which will be analyzed with psychophysiological equipment. Functional Near-Infrared Spectroscopy (fNIRS) has become more prominent for measuring the blood...
Show moreThe objective of this study was to assess low to high levels of Cognitive Workload by measuring heart rate and cortical blood flow in real-time. Four conditions were implemented into a within-subjects experimental design. Two conditions of difficulty and two conditions of trial order were used to illicit different levels of workload which will be analyzed with psychophysiological equipment. Functional Near-Infrared Spectroscopy (fNIRS) has become more prominent for measuring the blood oxygenation levels in the prefrontal cortex of individuals operating in hazardous work environments, students with learning disabilities, and in research for military training. This is due to the fNIR device being highly mobile, inexpensive, and able to produce a high-spatial resolution of the dorsolateral prefrontal cortex during executive functioning. Heart Rate will be measured by an Electrocardiogram, which will be used in concordance with fNIR oxygenation levels to predict if an individual is in a condition that produces low or high mental workload. Successfully utilizing heart rate and blood oxygenation data as predictors of cognitive workload may validate implementing multiple physiological devices together in real-time and may be a more accurate solution for preventing excessive workload.
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Date Issued: 2013
Identifier: CFH0004478, ucf:45070
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004478

Title: THE EFFECTS ON OPERATOR PERFORMANCE AND WORKLOAD WHEN GUNNERY AND ROBOTIC CONTROL TASKS ARE PERFORMED CONCURRENTLY.
Creator: Joyner, Carla, McCauley-Bell, Pamela, University of Central Florida
Abstract / Description: The purpose of this research was to examine operator workload and performance in a high risk, multi-task environment. Specifically, the research examined if a gunner of a Future Combat System, such as a Mounted Combat System, could effectively detect targets in the immediate environment while concurrently operating robotic assets in a remote environment. It also analyzed possible effects of individual difference factors, such as spatial ability and attentional control, on operator performance...
Show moreThe purpose of this research was to examine operator workload and performance in a high risk, multi-task environment. Specifically, the research examined if a gunner of a Future Combat System, such as a Mounted Combat System, could effectively detect targets in the immediate environment while concurrently operating robotic assets in a remote environment. It also analyzed possible effects of individual difference factors, such as spatial ability and attentional control, on operator performance and workload. The experimental conditions included a gunner baseline and concurrent task conditions where participants simultaneously performed gunnery tasks and one of the following tasks: monitor an unmanned ground vehicle (UGV) via a video feed (Monitor), manage a semi-autonomous UGV, and teleoperate a UGV (Teleop). The analysis showed that the asset condition significantly impacted gunnery performance with the gunner baseline having the highest number of targets detected (M = 13.600 , SD = 2.353), and concurrent Teleop condition the lowest (M = 9.325 , SD = 2.424). The research also found that high spatial ability participants tended to detect more targets than low spatial ability participants. Robotic task performance was also affect by the asset condition. The results showed that the robotic target detection rate was lower for the concurrent task conditions. A significant difference was seen between the UGV-baseline (80.1%) when participants performed UGV tasks only and UGV-concurrent conditions (67.5%) when the participants performed UGV tasks concurrently with gunnery tasks. Overall, this study revealed that there were performance decrements for the gunnery tasks as well as the robotic tasks when the tasks were performed concurrently.
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Date Issued: 2006
Identifier: CFE0000979, ucf:46704
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000979

Title: Simulation-Based Cognitive Workload Modeling and Evaluation of Adaptive Automation Invoking and Revoking Strategies.
Creator: Rusnock, Christina, Geiger, Christopher, Karwowski, Waldemar, Xanthopoulos, Petros, Reinerman, Lauren, University of Central Florida
Abstract / Description: In human-computer systems, such as supervisory control systems, large volumes of incoming and complex information can degrade overall system performance. Strategically integrating automation to offload tasks from the operator has been shown to increase not only human performance but also operator efficiency and safety. However, increased automation allows for increased task complexity, which can lead to high cognitive workload and degradation of situational awareness. Adaptive automation is...
Show moreIn human-computer systems, such as supervisory control systems, large volumes of incoming and complex information can degrade overall system performance. Strategically integrating automation to offload tasks from the operator has been shown to increase not only human performance but also operator efficiency and safety. However, increased automation allows for increased task complexity, which can lead to high cognitive workload and degradation of situational awareness. Adaptive automation is one potential solution to resolve these issues, while maintaining the benefits of traditional automation. Adaptive automation occurs dynamically, with the quantity of automated tasks changing in real-time to meet performance or workload goals. While numerous studies evaluate the relative performance of manual and adaptive systems, little attention has focused on the implications of selecting particular invoking or revoking strategies for adaptive automation. Thus, evaluations of adaptive systems tend to focus on the relative performance among multiple systems rather than the relative performance within a system.This study takes an intra-system approach specifically evaluating the relationship between cognitive workload and situational awareness that occurs when selecting a particular invoking-revoking strategy for an adaptive system. The case scenario is a human supervisory control situation that involves a system operator who receives and interprets intelligence outputs from multiple unmanned assets, and then identifies and reports potential threats and changes in the environment. In order to investigate this relationship between workload and situational awareness, discrete event simulation (DES) is used. DES is a standard technique in the analysis of systems, and the advantage of using DES to explore this relationship is that it can represent a human-computer system as the state of the system evolves over time. Furthermore, and most importantly, a well-designed DES model can represent the human operators, the tasks to be performed, and the cognitive demands placed on the operators. In addition to evaluating the cognitive workload to situational awareness tradeoff, this research demonstrates that DES can quite effectively model and predict human cognitive workload, specifically for system evaluation.This research finds that the predicted workload of the DES models highly correlates with well-established subjective measures and is more predictive of cognitive workload than numerous physiological measures. This research then uses the validated DES models to explore and predict the cognitive workload impacts of adaptive automation through various invoking and revoking strategies. The study provides insights into the workload-situational awareness tradeoffs that occur when selecting particular invoking and revoking strategies. First, in order to establish an appropriate target workload range, it is necessary to account for both performance goals and the portion of the workload-performance curve for the task in question. Second, establishing an invoking threshold may require a tradeoff between workload and situational awareness, which is influenced by the task's location on the workload-situational awareness continuum. Finally, this study finds that revoking strategies differ in their ability to achieve workload and situational awareness goals. For the case scenario examined, revoking strategies based on duration are best suited to improve workload, while revoking strategies based on revoking thresholds are better for maintaining situational awareness.
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Date Issued: 2013
Identifier: CFE0004927, ucf:49607
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004927

Title: Enhancing the effectiveness of Human-Robot teaming with a closed-loop system.
Creator: Teo, Grace, Szalma, James, Jentsch, Florian, Hancock, Peter, Matthews, Gerald, Reinerman, Lauren, University of Central Florida
Abstract / Description: With the development in robotics and the increasing deployment of robots, human-robot teams are set to be a mainstay in the future. However, our understanding of the effectiveness and impact of this new form of teaming is limited. Previous experience with technology and automa-tion has shown that technological aids do not always result in the intended consequences of im-proved performance and alleviation of workload and stress. No doubt a large part of this is due to the fact that the...
Show moreWith the development in robotics and the increasing deployment of robots, human-robot teams are set to be a mainstay in the future. However, our understanding of the effectiveness and impact of this new form of teaming is limited. Previous experience with technology and automa-tion has shown that technological aids do not always result in the intended consequences of im-proved performance and alleviation of workload and stress. No doubt a large part of this is due to the fact that the relationships among taskload, workload and performance are complex as hu-man operators interact dynamically with tasks and technology. Measures of workload are also varied and differentially sensitive. There is also the added challenge posed by multi-tasking envi-ronments which typify most real-world situations. Given all this, efforts in designing technologi-cal aids, such as an adaptive robot aid in the context of human-robot teaming, would require a workload model that reflects the intricate relationship between taskload and the individual opera-tor's experience of workload. Such a model can then be used to drive a closed-loop system on which adaptive robot aiding can be based. The present research sought to investigate the effec-tiveness of a closed-loop system, based on a model of workload, in enhancing performance in a simulated military mission involving a human-robot team. Results showed that adaptive robot aid driven by workload needs as assessed by physiological measures resulted in greater improve-ments in performance compared to robot aid that was imposed by the system.
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Date Issued: 2015
Identifier: CFE0006403, ucf:51485
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006403

Title: Investigating the Impact of Levels of Experience on Workload During Nuclear Power Plant Operations.
Creator: Harris, Jonathan, Reinerman, Lauren, Karwowski, Waldemar, Hancock, Peter, Barber, Daniel, University of Central Florida
Abstract / Description: The human-machine interface (HMI) of a Nuclear Power Plant (NPP) Main Control Room (MCR) is complex. Understanding HMI factors that influence Reactor Operator (RO) performance and workload when controlling an NPP is important. The Nuclear Regulatory Commission (NRC) began a program of research known as the Human Performance Test Facility (HPTF) with the goal of collecting human performance data to better understand cognitive and physical elements that support safe control room operation. The...
Show moreThe human-machine interface (HMI) of a Nuclear Power Plant (NPP) Main Control Room (MCR) is complex. Understanding HMI factors that influence Reactor Operator (RO) performance and workload when controlling an NPP is important. The Nuclear Regulatory Commission (NRC) began a program of research known as the Human Performance Test Facility (HPTF) with the goal of collecting human performance data to better understand cognitive and physical elements that support safe control room operation. The HPTF team developed an experimental methodology to evaluate workload using perceived ratings, performance measures, and physiological correlates. This methodology focuses on tasks commonly performed during operations in an NPP. These tasks include monitoring plant parameters, following defined procedures, and manipulating controls to change the state of the NPP. O'Hara and colleagues developed a framework for task classification. Reinerman-Jones and colleagues modified this framework such that monitoring and detection are separate task types. The task types (i.e., checking, detection, and response implementation) selected for experimentation are composed of steps within defined operating procedures that are rule-based. Testing workload using sufficient numbers of ROs is impractical due to limited availability. The HPTF has developed the (")equal but different(") principle. This principle attempts to simplify complex tasks, such that novices can perform them and experience equivalent workload trends as an expert would when performing the original task. The validity of using the (")equal but different(") principle with novices in place of experts is uncertain. This research addresses this uncertainty by comparing novices and experts using the (")equal but different(") principle. Novices performed four tasks within each of the three task types using a simplified Instrument and Control (I(&)C) panel and a reduced 3-way communication instruction set. Experts performed the same four tasks within each task type with a fully configured I(&)C panel and a complete 3-way instruction set. Overall, the experts across the three task types tended to rate level of perceived workload lower than novices. However, experts also rated themselves as performing worse for the three task types than novices. Experts performed better than novices when it came to identifying correct I(&)C; however, their 3-way communication performance was worse. Physiological measures from EEG between the two groups were not statistically different. ECG findings did show a slight difference.The methodology and associated findings has applicability for MCR designs and regulation recommendations. Novice populations are easier to access than experts and the present research shows that when properly designed, novices can serve in complex operator positions.
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Date Issued: 2017
Identifier: CFE0006946, ucf:51634
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006946

Title: The Effects of Presentation Mode and Pace on Learning Immunology with Computer Simulation: A Cognitive Evaluation of a Multimedia Learning Resource.
Creator: Bradley-Radakovich, Kristy, Kincaid, John, Khaled, Annette, McDaniel, Rudy, Greenwood-Ericksen, Adams, University of Central Florida
Abstract / Description: Multimedia learning tools have the potential to benefit instructors and learners as supplemental learning materials. However, when such tools are designed inappropriately, this can increase cognitive taxation and impede learning, rendering the tools ineffective. Guided by the theoretical underpinnings provided by cognitive load theory and the cognitive theory of multimedia learning, this study sought to empirically evaluate the effectiveness of a multimedia simulation tool aimed at teaching...
Show moreMultimedia learning tools have the potential to benefit instructors and learners as supplemental learning materials. However, when such tools are designed inappropriately, this can increase cognitive taxation and impede learning, rendering the tools ineffective. Guided by the theoretical underpinnings provided by cognitive load theory and the cognitive theory of multimedia learning, this study sought to empirically evaluate the effectiveness of a multimedia simulation tool aimed at teaching immunology to novices in an instructional setting. The instructional mode and pace of the tool were manipulated, the three levels of each variable yielding nine experimental groups. The effects of mode and pace on workload and learning scores were observed. The results of this study did not support the theory-driven hypotheses. No significant learning gains were found between the configuration groups, however overall significant learning gains were subsequently found when disregarding mode and pace configuration. Pace was found to influence workload such that fast pace presentations significantly increased workload ratings and a significant interaction of mode and pace was found for workload ratings. The findings suggest that the learning material was too high in intrinsic load and the working memory of the learners too highly taxed for the benefits of applying the design principles to be observed. Results also illustrate a potential exception to the conditions of the design principles when complex terminology is to be presented. Workload findings interpreted in the context of stress adaptation potentially indicate points at which learners at maximum capacity begin to exhibit performance decrements.
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Date Issued: 2011
Identifier: CFE0004090, ucf:49150
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004090

Title: A Simulation-Based Task Analysis using Agent-Based, Discrete Event and System Dynamics simulation.
Creator: Angelopoulou, Anastasia, Karwowski, Waldemar, Kincaid, John, Xanthopoulos, Petros, Hancock, Peter, University of Central Florida
Abstract / Description: Recent advances in technology have increased the need for using simulation models to analyze tasks and obtain human performance data. A variety of task analysis approaches and tools have been proposed and developed over the years. Over 100 task analysis methods have been reported in the literature. However, most of the developed methods and tools allow for representation of the static aspects of the tasks performed by expert system-driven human operators, neglecting aspects of the work...
Show moreRecent advances in technology have increased the need for using simulation models to analyze tasks and obtain human performance data. A variety of task analysis approaches and tools have been proposed and developed over the years. Over 100 task analysis methods have been reported in the literature. However, most of the developed methods and tools allow for representation of the static aspects of the tasks performed by expert system-driven human operators, neglecting aspects of the work environment, i.e. physical layout, and dynamic aspects of the task. The use of simulation can help face the new challenges in the field of task analysis as it allows for simulation of the dynamic aspects of the tasks, the humans performing them, and their locations in the environment. Modeling and/or simulation task analysis tools and techniques have been proven to be effective in task analysis, workload, and human reliability assessment. However, most of the existing task analysis simulation models and tools lack features that allow for consideration of errors, workload, level of operator's expertise and skills, among others. In addition, the current task analysis simulation tools require basic training on the tool to allow for modeling the flow of task analysis process and/or error and workload assessment. The modeling process is usually achieved using drag and drop functionality and, in some cases, programming skills.This research focuses on automating the modeling process and simulating individuals (or groups of individuals) performing tasks in a dynamic work environment in any domain. The main objective of this research is to develop a universal tool that allows for modeling and simulation of task analysis models in a short amount of time with limited need for training or knowledge of modeling and simulation theory. A Universal Task Analysis Simulation Modeling (UTASiMo) tool can be used for automatically generating simulation models that analyze the tasks performed by human operators. UTASiMo is a multi-method modeling and simulation tool developed as a combination of agent-based, discrete event, and system dynamics simulation models. A generic multi-method modeling and simulation framework, named 3M(&)S Framework, as well as the Unified Modeling Language have been used for the design of the conceptual model and the implementation of the simulation tool. UTASiMo-generated models are dynamically created during run-time based on user inputs. The simulation results include estimations of operator workload, task completion time, and probability of human errors based on human operator variability and task structure.
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Date Issued: 2015
Identifier: CFE0006252, ucf:51040
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006252

workload (13)	+ -
Workload (4)	+ -
Mental Workload (2)	+ -
Vigilance (2)	+ -
attention (2)	+ -

automation (2)	+ -
human performance (2)	+ -
mental workload (2)	+ -
multiple resource theory (2)	+ -
performance (2)	+ -
simulation (2)	+ -
stress (2)	+ -
Adaptive Automation (1)	+ -
Cognition (1)	+ -
Cognitive Workload (1)	+ -
Configural Displays (1)	+ -
Data ExtractionPerformance (1)	+ -
Discrete-Event Simulation (1)	+ -
Display Design (1)	+ -
Dual-Task (1)	+ -
ECG (1)	+ -
EEG (1)	+ -
Equivalency analysis (1)	+ -
Expertise (1)	+ -
Game (1)	+ -
HRV (1)	+ -
Human Performance (1)	+ -
Human Performance Modeling (1)	+ -
ISA (1)	+ -
ISR (1)	+ -

ETD Collection (22)	+ -
Honors Collection (2)	+ -

University of Central Florida (24)	+ -
Hancock, Peter (14)	+ -
Szalma, James (7)	+ -
Mouloua, Mustapha (6)	+ -
Reinerman, Lauren (6)	+ -

Karwowski, Waldemar (5)	+ -
Kincaid, John (3)	+ -
Sims, Valerie (3)	+ -
Xanthopoulos, Petros (3)	+ -
Joseph, Dana (2)	+ -
Lackey, Stephanie (2)	+ -
Matthews, Gerald (2)	+ -
Taylor, Grant (2)	+ -
Abich, Julian (1)	+ -
Allen, Robert (1)	+ -
Angelopoulou, Anastasia (1)	+ -
Barber, Daniel (1)	+ -
Bohil, Corey (1)	+ -
Bradley-Radakovich, Kristy (1)	+ -
Brill, John (1)	+ -
Claypoole, Victoria (1)	+ -
Crumpton-Young, Lesia (1)	+ -
Duany, John (1)	+ -
Elshennawy, Ahmad (1)	+ -
Fok, Audrey (1)	+ -
Fraulini, Nicholas (1)	+ -
Ganey, Harriss (1)	+ -
Geiger, Christopher (1)	+ -
Gilson, Richard (1)	+ -
Greenwood-Ericksen, Adams (1)	+ -

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