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- Title
- A Short Window Granger Causality Approach to Identify Brain Functional Pattern Associated with Changes of Performance Induced by Sleep Deprivation.
- Creator
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Li, Muyuan, Karwowski, Waldemar, Xanthopoulos, Petros, Hancock, Peter, Mikusinski, Piotr, University of Central Florida
- Abstract / Description
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The comprehensive effect of sleep deprivation on biological and behavioral functions largely remains unknown. There is evidence to support that human sleep must be of sufficient duration and physiological continuity to ensure neurocognitive performance while we are waking. Insufficient sleep would lead to high risk of human-error related to accidents, injuries or even fatal outcomes. However, in modern society, more and more people suffer from sleep deprivation because of the increasing...
Show moreThe comprehensive effect of sleep deprivation on biological and behavioral functions largely remains unknown. There is evidence to support that human sleep must be of sufficient duration and physiological continuity to ensure neurocognitive performance while we are waking. Insufficient sleep would lead to high risk of human-error related to accidents, injuries or even fatal outcomes. However, in modern society, more and more people suffer from sleep deprivation because of the increasing social, academic or occupational demand. It is important to study the effect of sleep deprivation, not only on task performance, but also on neurocognitive functions. Recent research that has explored brain effective connectivity has demonstrated the directed inference interaction among pairs of brain areas, which may bring important insight to understand how brain works to support neurocognitive function. This research aimed to identify the brain effective connectivity pattern associated with changes of a task performance, response time, following sleep deprivation. Experiments were conducted by colleagues at Neuroergonomics Department at Jagiellonian University, Krakow, Poland. Ten healthy young women, with an average age of 23-year-old, performed visual spatial sustained-attention tasks under two conditions: (1) the rest-wakeful (RW) condition, where participants had their usual sleep and (2) the sleep-deprived (SD) condition, where participants had 3 hours less sleep than their usual sleep, for 7 nights (amounting to 21 h of sleep debt).Measures included eye tracking performance and functional magnetic resonance imaging (fMRI). In each condition, each subject's eye-position was monitored through 13 sessions, each with 46 trials, while fMRI data was recorded. There were two task performance measures, accuracy and response time. Accuracy measured the proportion of correct responses of all trials in each session. Response time measured the average amount of milliseconds until participants gazed at the target stimuli in each session. An experimental session could be treated as a short window. By splitting long trials of fMRI data into consecutive windows, Granger causality was applied based on short trials of fMRI data. This procedure helped to calculate pairwise causal influences with respect to time-varying property in brain causal interaction. Causal influence results were then averaged across sessions to create one matrix for each participant. This matrix was averaged within each condition to formulate a model of brain effective connectivity, which also served as a basis of comparison. In conclusion, significant effect of sleep deprivation was found on response time and brain effective connectivity. In addition, the change of brain effective connectivity after sleep deprivation was linked to the change of response time. First, an analysis of variance (ANOVA) showed significant difference for response time between the RW condition and the SD condition. No significant changes for accuracy were found. A paired t-test showed that response time was significantly shorter in sleep deprivation for the visual spatial sustained-attention task. Second, Granger causality analysis demonstrated a reduction of bidirectional connectivity and an increase of directed influences from low-level brain areas to high-level brain areas after sleep deprivation. This observation suggested that sleep deprivation provoked the effective connectivity engaged in salient stimuli processing, but inhibited the effective connectivity in biasing selection of attention on task and in maintaining self-awareness in day time. Furthermore, in the SD condition, attention at the visual spatial task seemed to be driven by a bottom-up modulation mechanism. Third, a relationship was found between brain effective connectivity with response time. Decreases of Granger causal influences in two directions, from medial frontal lobe to sub cortical gray nuclei and from medial parietal lobe to sub cortical gray nuclei, were associated with shorter response time in the SD condition. Additionally, an increase of Granger causal influence from medial parietal lobe to cerebellum was associated with longer response time in the SD condition.
Show less - Date Issued
- 2014
- Identifier
- CFE0005825, ucf:50922
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005825
- Title
- A Simulation-Based Task Analysis using Agent-Based, Discrete Event and System Dynamics simulation.
- Creator
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Angelopoulou, Anastasia, Karwowski, Waldemar, Kincaid, John, Xanthopoulos, Petros, Hancock, Peter, University of Central Florida
- Abstract / Description
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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.
Show less - Date Issued
- 2015
- Identifier
- CFE0006252, ucf:51040
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006252
- Title
- A study of EEG signature associated with Emotional and stress responses due to cyberbullying.
- Creator
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Alhujailli, Ashraf, Karwowski, Waldemar, Reinerman, Lauren, Hancock, Peter, Wan, Thomas, University of Central Florida
- Abstract / Description
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The human brain processes vital information regarding human feelings. Prior research has focused on the problems of underage bullying, workplace bullying, burnout, mobbing and, most recently, cyberbullying. Scholars have traditionally examined the adverse outcomes of cyberbullying using subjective measures of stress and emotion for decades. However, very few studies examined cyberbullying using objective measures like EEG. The main goal of this study was to explore the relationship between...
Show moreThe human brain processes vital information regarding human feelings. Prior research has focused on the problems of underage bullying, workplace bullying, burnout, mobbing and, most recently, cyberbullying. Scholars have traditionally examined the adverse outcomes of cyberbullying using subjective measures of stress and emotion for decades. However, very few studies examined cyberbullying using objective measures like EEG. The main goal of this study was to explore the relationship between the brain's EEG, expressed by the power spectral density, and emotions and stress due to two types of cyberbullying, specifically: 1) social exclusion, and 2) verbal harassment. This research also examined how cyberbullying factors of social interaction and publicity affect the emotional and stress responses. EEG data were collected from twenty-nine undergraduate students, aged 18-22, using 10/5 EEG system with 64 channels. Each cyberbullying experimental condition was treated as an independent study. The first study investigated the effects of social exclusion on EEG activity and the related emotional and stress factors while playing a virtual ball-tossing game known as cyberball. EEG results showed significant differences in alpha and beta power in the right posterior brain regions due to social exclusion. There were also significant differences in beta and gamma power in the left anterior brain regions due to social exclusion. The results suggest that EEG activity in the left anterior brain region may be important to identify social exclusion. The second study utilized a hypothetical scenario presented as impolite or complimentary online comments. EEG results showed marginally significant differences in gamma power at right- and left- anterior and midline brain regions due to verbal harassment. The results suggest that changes in gamma power at anterior brain regions might play an essential role in the processing of verbal harassment information. Self-reported measures confirmed that verbal harassment was more distressing than social exclusion.
Show less - Date Issued
- 2018
- Identifier
- CFE0006968, ucf:51628
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006968
- Title
- A study of nonlinear dynamics of EEG responses to simulated unmanned vehicle tasks.
- Creator
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Xu, Ziqing, Karwowski, Waldemar, Hancock, Peter, Reinerman, Lauren, Mikusinski, Piotr, University of Central Florida
- Abstract / Description
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In the contemporary world, mental workload becomes higher as technology evolves and task demand becomes overwhelming. The operators of a system are usually required to complete tasks with higher complicity within a shorter period of time. Continuous operation under a high level of mental workload can be a major source of risk and human error, thus put the operator in a hazardous working environment. Therefore, it is necessary to monitor and assess mental workload. In this study, an unmanned...
Show moreIn the contemporary world, mental workload becomes higher as technology evolves and task demand becomes overwhelming. The operators of a system are usually required to complete tasks with higher complicity within a shorter period of time. Continuous operation under a high level of mental workload can be a major source of risk and human error, thus put the operator in a hazardous working environment. Therefore, it is necessary to monitor and assess mental workload. In this study, an unmanned vehicle operation with visual detection tasks was investigated by means of nonlinear analysis of EEG time series. Nonlinear analysis is considered more advantageous compared with traditional power spectrum analysis of EEG. Besides, nonlinear analysis is more capable to capture the nature of EEG data and human performance, which is a process that subjects to constant changes. By examining the nonlinear dynamics of EEG, it is more likely to obtain a deeper understanding of brain activity.The objective of this study is to investigate the mental workload under different task levels through the examination of brain activity via nonlinear dynamics of EEG time series in simulated unmanned ground vehicle visual detection tasks.The experiment was conducted by the team lead by Dr. Lauren Reinerman Jones at Institute for Simulation (&) Training, University of Central Florida. One hundred and fifty subjects participated the experiment to complete four visual detection task scenarios (1) change detection, (2) threat detection task, (3) dual task with different change detection task rates, and (4) dual task with different threat detection task rates. Their EEG was recorded during performing the tasks at nine EEG channels. This study develops a massive data processing program to calculate the largest Lyapunov exponent, correlation dimension of the EEG data. This study also develops the program for performing 0-1 test on the EEG data in Python language environment. The result of this study verifies the existence of chaotic dynamics in EEG time series, reveals the change in brain activity as the effect of changing task demand in more detailed level, and obtains new insights from the psychophysiological mental workload measurement used in the preliminary study. The results of this study verified the existence of the chaotic dynamics in the EEG time series. This study also supported the hypothesis that EEG data exhibits change in the level of nonlinearity corresponding to differed task levels. The nonlinear analysis of EEG time series data is able to discriminate the change in brain activity derived from the changes in task load. All nonlinear dynamics analysis techniques used in this study is able to find the difference of nonlinearity in EEG among task levels, as well as between single task scenario and dual task scenario.
Show less - Date Issued
- 2019
- Identifier
- CFE0007558, ucf:52615
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007558
- Title
- A Study of Perceptions on Incident Response Exercises, Information Sharing, Situational Awareness, and Incident Response Planning in Power Grid Utilities.
- Creator
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Garmon, Joseph, Karwowski, Waldemar, Hancock, Peter, Elshennawy, Ahmad, Wan, Thomas, University of Central Florida
- Abstract / Description
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The power grid is facing increasing risks from a cybersecurity attack. Attacks that shut off electricity in Ukraine have already occurred, and successful compromises of the power grid that did not shut off electricity to customers have been privately disclosed in North America. The objective of this study is to identify how perceptions of various factors emphasized in the electric sector affect incident response planning. Methods used include a survey of 229 power grid personnel and the use...
Show moreThe power grid is facing increasing risks from a cybersecurity attack. Attacks that shut off electricity in Ukraine have already occurred, and successful compromises of the power grid that did not shut off electricity to customers have been privately disclosed in North America. The objective of this study is to identify how perceptions of various factors emphasized in the electric sector affect incident response planning. Methods used include a survey of 229 power grid personnel and the use of partial least squares structural equation modeling to identify causal relationships. This study reveals the relationships between perceptions by personnel responsible for cybersecurity, regarding incident response exercises, information sharing, and situational awareness, and incident response planning. The results confirm that the efforts by the industry on these topics have advanced planning for a potential attack.
Show less - Date Issued
- 2019
- Identifier
- CFE0007805, ucf:52349
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007805
- Title
- An Agent Based Model to assess crew temporal variability during U.S. Navy shipboard operations.
- Creator
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Muhs, Kevin, Karwowski, Waldemar, Elshennawy, Ahmad, Hancock, Peter, Sjoden, Glenn, University of Central Florida
- Abstract / Description
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Understanding the factors that affect human performance variability as well as their temporal impacts is an essential element in fully integrating and designing complex, adaptive environments. This understanding is particularly necessary for high stakes, time-critical routines such as those performed during nuclear reactor, air traffic control, and military operations. Over the last three decades significant efforts have emerged to demonstrate and apply a host of techniques to include...
Show moreUnderstanding the factors that affect human performance variability as well as their temporal impacts is an essential element in fully integrating and designing complex, adaptive environments. This understanding is particularly necessary for high stakes, time-critical routines such as those performed during nuclear reactor, air traffic control, and military operations. Over the last three decades significant efforts have emerged to demonstrate and apply a host of techniques to include Discrete Event Simulation, Bayesian Belief Networks, Neural Networks, and a multitude of existing software applications to provide relevant assessments of human task performance and temporal variability. The objective of this research was to design and develop a novel Agent Based Modeling and Simulation (ABMS) methodology to generate a timeline of work and assess impacts of crew temporal variability during U.S. Navy Small Boat Defense operations in littoral waters.The developed ABMS methodology included human performance models for six crew members (agents) as well as a threat craft, and incorporated varying levels of crew capability and task support. AnyLogic ABMS software was used to simultaneously provide detailed measures of individual sailor performance and of system-level emergent behavior. This methodology and these models were adapted and built to assure extensibility across a broad range of U.S. Navy shipboard operations.Application of the developed ABMS methodology effectively demonstrated a way to visualize and quantify impacts/uncertainties of human temporal variability on both workload and crew effectiveness during U.S. Navy shipboard operations.
Show less - Date Issued
- 2018
- Identifier
- CFE0007592, ucf:52549
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007592
- Title
- AN HEDONOMIC EVALUATION OF PLEASURABLE HUMAN-TECHNOLOGY EXPERIENCE: THE EFFECT OF EXPOSURE AND AESTHETICS ON THE EXPERIENCE OF FLOW.
- Creator
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Murphy, Lauren, Hancock, Peter, University of Central Florida
- Abstract / Description
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A framework was developed called the Extended Hedonomic Hierarchy (EHH) that provides a basis for evaluating pleasurable human-system experience. Results from a number of experiments within this framework that evaluated specific dimensions of the framework are reported. The 'Exposure' component of the EHH framework and hedonics of the system were investigated to see how changes would affect other dimensions, such as the occurrence of flow, the mode of interaction, and the needs of the user....
Show moreA framework was developed called the Extended Hedonomic Hierarchy (EHH) that provides a basis for evaluating pleasurable human-system experience. Results from a number of experiments within this framework that evaluated specific dimensions of the framework are reported. The 'Exposure' component of the EHH framework and hedonics of the system were investigated to see how changes would affect other dimensions, such as the occurrence of flow, the mode of interaction, and the needs of the user. Simulations and video games were used to investigate how repeated exposure affects flow, interaction mode, and the user needs. The Kansei Engineering method was used to measure user needs and investigate the effect of different hedonic properties of the system on user needs and flow. Findings reveal that: (a) pleasurable human-system experience increases linearly with repeated exposure to the technology of interest; (b) an habituation effect of flow mediated by day; (c) motivation to satisfy human need for technology is hierarchically structured and contributes to pleasurable human-system experience; (d) interactivity is hierarchically structured and seamless mode of interaction is a behavioral outcome of pleasurable human-system experience; (e) there are individual differences among users that affect the likelihood of experiencing pleasurable human-system interaction; (f) performance is positively correlated to flow and (g) the method of kansei engineering provides data from which informed decisions about design can be made and empirical research can be conducted. Suggestions for (a) making Hedonomics a reality in industry, the workplace, and in the field of Human Factors, (b) future research directions for Hedonomics, and (c) principles and guidelines for the practice of Hedonomics are discussed.
Show less - Date Issued
- 2005
- Identifier
- CFE0000875, ucf:46650
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000875
- Title
- Applied Error Related Negativity: Single Electrode Electroencephalography in Complex Visual Stimuli.
- Creator
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Sawyer, Benjamin, Karwowski, Waldemar, Hancock, Peter, Xanthopoulos, Petros, University of Central Florida
- Abstract / Description
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Error related negativity (ERN) is a pronounced negative evoked response potential (ERP) that follows a known error. This neural pattern has the potential to communicate user awareness of incorrect actions within milliseconds. While the implications for human-machine interface and augmented cognition are exciting, the ERN has historically been evoked only in the laboratory using complex equipment while presenting simple visual stimuli such as letters and symbols. To effectively harness the...
Show moreError related negativity (ERN) is a pronounced negative evoked response potential (ERP) that follows a known error. This neural pattern has the potential to communicate user awareness of incorrect actions within milliseconds. While the implications for human-machine interface and augmented cognition are exciting, the ERN has historically been evoked only in the laboratory using complex equipment while presenting simple visual stimuli such as letters and symbols. To effectively harness the applied potential of the ERN, detection must be accomplished in complex environments using simple, preferably single-electrode, EEG systems feasible for integration into field and workplace-ready equipment. The present project attempted to use static photographs to evoke and successfully detect the ERN in a complex visual search task: motorcycle conspicuity. Drivers regularly fail to see motorcycles, with tragic results. To reproduce the issue in the lab, static pictures of traffic were presented, either including or not including motorcycles. A standard flanker letter task replicated from a classic ERN study (Gehring et al., 1993) was run alongside, with both studies requiring a binary response. Results showed that the ERN could be clearly detected in both tasks, even when limiting data to a single electrode in the absence of artifact correction. These results support the feasibility of applied ERN detection in complex visual search in static images. Implications and opportunities will be discussed, limitations of the study explained, and future directions explored.
Show less - Date Issued
- 2014
- Identifier
- CFE0005885, ucf:50886
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005885
- Title
- Assessing Safety Culture among Personnel in Governmental Construction Sites at Saudi Arabia: A Quantitative Study Approach.
- Creator
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Alrehaili, Omar, Karwowski, Waldemar, Elshennawy, Ahmad, Hancock, Peter, Mikusinski, Piotr, University of Central Florida
- Abstract / Description
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Safety is an essential issue for organizations to survive, especially for hazardous industries such as the construction industry. The construction industry is considered to be one of the major industries that help in the growth of the economy and the infrastructure of all countries. Recently, scholars have paid increasing attention to the concept of safety culture due to its role in decreasing the occurrences of accidents and injuries. Safety culture has become the focus of all industries and...
Show moreSafety is an essential issue for organizations to survive, especially for hazardous industries such as the construction industry. The construction industry is considered to be one of the major industries that help in the growth of the economy and the infrastructure of all countries. Recently, scholars have paid increasing attention to the concept of safety culture due to its role in decreasing the occurrences of accidents and injuries. Safety culture has become the focus of all industries and has received much attention in recent years, especially within the construction industry. Absence of this culture is a major cause of injuries and accidents in the construction field. In the construction industry, personnel's perception of safety culture is vital to prevent accidents or behavior misconduct. Also, focusing on personnel's safety culture on construction sites provides an opportunity to decrease risks and unsafe behaviors to improve the overall safety level. Workers' performance and behaviors are shaped by their awareness and view of safety culture inside their work environment. Generally, safety performance in the construction field is still unsatisfactory based on reporting records.The present study observed the influence of safety culture on construction's personnel's safety performance on large governmental construction projects in Saudi Arabia. Construction personnel's safety performance is measured by their attitude toward violations and error behaviors. This research also exams the role of personnel's motivation toward construction safety as a mediating variable between construction safety culture and safety performance constructs, including error and violation behaviors. The research adopted a quantitative method by using a questionnaire for the purpose of data collection and analysis. A total of 434 questionnaires were collected from construction personnel including project managers, engineers, and supervisors through their voluntary participation in this study. Statistical analysis was used to analyze the data collected including descriptive statistics, confirmatory factor analysis (CFA) and structural equation modeling (SEM) techniques. Confirmatory factor analysis is used for validating each factor with its measurable items. Finally, this study applied the concept of structural equation modeling (SEM) to evaluate the correlation between all latent variables in the study's conceptualized model.The outcomes of the study show that safety culture has a direct influence on construction personnel's attitudes toward violations and an indirect effect on construction personnel's error behavior. Furthermore, safety culture has a significant effect on improving safety motivation, as well. Safety motivation for construction safety has a direct effect on errors behaviors. Conversely, safety motivation does not have a mediating effect on construction personnel's attitudes toward violations. Therefore, safety motivation's mediating role was significant only between safety culture and errors behaviors.This research has added to the existing knowledge about the important part of safety culture as a key interpreter of safety performance in construction field. The current study contributes to psychological safety through examining the influence of safety culture as the interpreter for enhancing motivation for construction safety. Additionally, this research evaluated safety culture's influence on construction personnel's attitudes toward violations and construction personnel's error behavior. The outcomes of the study are useful and recommended to be used by construction management to better pinpoint the reasons for unsafe behaviors within the construction industry. The results of this research highlights management's role in determining, and affecting, workers' behaviors.
Show less - Date Issued
- 2016
- Identifier
- CFE0006434, ucf:51470
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006434
- Title
- Assessing Safety Culture among Pilots in Saudi Airlines: A Quantitative Study Approach.
- Creator
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Alsowayigh, Mohammad, Karwowski, Waldemar, Elshennawy, Ahmad, Lee, Gene, Hancock, Peter, Mikusinski, Piotr, University of Central Florida
- Abstract / Description
-
In high- risk industries, such as aviation, safety is a key for organization survivor. Most accidents involve human losses and bring substantial cost to organizations. Accidents can devastate the reputation and profitability of any organization. In aviation, more than 80% of aircraft accidents are related to human errors. Safety culture has substantial impact on the success of any organization. Employees' performance and behaviors are influenced by their perception of safety culture within...
Show moreIn high- risk industries, such as aviation, safety is a key for organization survivor. Most accidents involve human losses and bring substantial cost to organizations. Accidents can devastate the reputation and profitability of any organization. In aviation, more than 80% of aircraft accidents are related to human errors. Safety culture has substantial impact on the success of any organization. Employees' performance and behaviors are influenced by their perception of safety culture within their organization. In the aviation industry, pilots are considered the last resort to prevent accidents or mishaps in the air or ground. The focus on pilots' perception of safety culture is vital to understand how the airline can influence pilots' behaviors in the flight deck, and provide opportunities to minimize risk or unsafe behavior in the future. The present study examined the effect of safety culture on safety performance among pilots of Saudi Airlines. Safety performance was measured by pilot attitude toward violations and pilot error behavior. The study further analyzed the mediating role of pilot commitment to the airline between safety culture and measures of safety performance. The study used a quantitative approach using survey questionnaire to collect the data. A total of 247 commercial airline pilots, captain and first officer, flying at Saudi Airlines voluntarily participated in the study. Confirmatory factor analysis was conducted to validate each latent construct. The study used structural equation modeling (SEM) to analyze the relationship between all variables in the study using AMOS 22 software. The study results revealed that safety culture had a direct effect on pilot attitude toward violations and indirect effect on pilot error behavior. Moreover, safety culture had strong effect on enhancing pilot commitment to the airline. The mediating role of pilot commitment to the airline was not significant, and could not mediate the relationship between safety culture and measures of safety performance. The present research contributed to the current state of knowledge about the significant role of safety culture as a main predictor of safety performance in civil aviation. The present study contributes to aviation psychology by analyzing the effect of safety culture as a predictor for improving pilot commitment to the airline. In addition, this research analyzed the effect of safety culture on pilot attitude toward violations and pilot error behavior. Study findings can be used by airline management to better identify causes of unsafe behavior inside the cockpit. The outcomes of this research emphasize the role of management in shaping and affecting employees' behaviors and attitudes.
Show less - Date Issued
- 2014
- Identifier
- CFE0005454, ucf:50371
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005454
- Title
- Assessing the Effectiveness of Workload Measures in the Nuclear Domain.
- Creator
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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.
Show less - Date Issued
- 2014
- Identifier
- CFE0005666, ucf:50188
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005666
- Title
- Assessment of Information Security Culture in Higher Education.
- Creator
-
Glaspie, Henry, Karwowski, Waldemar, Wan, Thomas, Hancock, Peter, Caulkins, Bruce, University of Central Florida
- Abstract / Description
-
Information security programs are instituted by organizations to provide guidance to their users who handle their data and systems. The main goal of these programs is to protect the organization's information assets through the creation and cultivation of a positive information security culture within the organization. As the collection and use of data expands in all economic sectors, the threat of data breach due to human error increases. Employee's behavior towards information security is...
Show moreInformation security programs are instituted by organizations to provide guidance to their users who handle their data and systems. The main goal of these programs is to protect the organization's information assets through the creation and cultivation of a positive information security culture within the organization. As the collection and use of data expands in all economic sectors, the threat of data breach due to human error increases. Employee's behavior towards information security is influenced by the organizations information security programs and the overall information security culture. This study examines the human factors of an information security program and their effect on the information security culture. These human factors consist of stringency of organizational policies, behavior deterrence, employee attitudes towards information security, training and awareness, and management support of the information security programs. A survey questionnaire was given to employees in the Florida College System to measure the human aspects of the information security programs. Confirmatory factor analysis (CFA) and Structural Equation Modeling (SEM) were used to investigate the relationships between the variables in the study using IBM(&)#174; SPSS(&)#174; Amos 24 software. The study results show that management support and behavior deterrence have a significant positive relationship with information security. Additionally, the results show no significant association between information security culture and organization policies, employee commitment and employee awareness. This suggests a need for further refinement of the model and the survey tool design to properly assess human factors of information security programs and their effects on the organizational security culture.
Show less - Date Issued
- 2018
- Identifier
- CFE0007184, ucf:52272
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007184
- Title
- Assessment of Instructional Presentation For Emergency Evacuation Assistive Technology.
- Creator
-
Boyce, Michael, Smither, Janan, Joseph, Dana, Hancock, Peter, Bowers, Clint, Wilson, Darren, University of Central Florida
- Abstract / Description
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It is often the case that emergency first responders are well equipped and trained to deal with a situation that involves evacuation of someone with a physical disability. However, emergency responders are not always the first line of defense, or they may be otherwise occupied with assisting others. This research examined the effects of instructions for emergency stair travel devices on untrained or novice users. It was hypothesized that through redesign of the evacuation instructions,...
Show moreIt is often the case that emergency first responders are well equipped and trained to deal with a situation that involves evacuation of someone with a physical disability. However, emergency responders are not always the first line of defense, or they may be otherwise occupied with assisting others. This research examined the effects of instructions for emergency stair travel devices on untrained or novice users. It was hypothesized that through redesign of the evacuation instructions, untrained individuals would be able to successfully prepare an evacuation chair and secure someone with a disability more effectively and efficiently. A pre-post study design was used with an instructional redesign occurring as the manipulation between phases. There was an improved subjective understanding and improved performance metrics, such as reduced time on task and a reduction of the number of instructional glances, across three evacuation chairs when using the redesigned instruction sets. The study demonstrated that visual instruction style can account for a significant portion of explained variance in the operation of emergency stair travel devices. It also showed that improvements in instruction style can reduce time on task across device type and age group. The study failed to demonstrate that there was a performance decrement for older adults in comparison to younger adults because of the cognitive slowing of older adult information processing abilities. Results from this study can be used to support future iterations of the Emergency Stair Travel Device Standard (RESNA ED-1) to ensure that instructional design is standardized and optimized for the best performance possible.
Show less - Date Issued
- 2014
- Identifier
- CFE0005136, ucf:50694
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005136
- Title
- Beyond Compliance: Examining the Role of Motivation in Vigilance Performance.
- Creator
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Dewar, Alexis, Szalma, James, Sims, Valerie, Hancock, Peter, Matthews, Gerald, University of Central Florida
- Abstract / Description
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Vigilance, or sustained attention, is the capacity to attend to information for a prolonged period of time (Davies (&) Parasuraman, 1982; Jerison, 1970; Warm, 1977). Due to limitations of the human nervous system, as well as the environmental context, attention can begin to wane over time. This results in a phenomenon referred to as the vigilance decrement, or a decline in vigilance performance as a function of time. The vigilance decrement can manifest as poorer attention and is thusly...
Show moreVigilance, or sustained attention, is the capacity to attend to information for a prolonged period of time (Davies (&) Parasuraman, 1982; Jerison, 1970; Warm, 1977). Due to limitations of the human nervous system, as well as the environmental context, attention can begin to wane over time. This results in a phenomenon referred to as the vigilance decrement, or a decline in vigilance performance as a function of time. The vigilance decrement can manifest as poorer attention and is thusly associated with poor performance, which is defined behaviorally as more lapses in the detection of critical signals and an increase in response time to these signals during watch. Given this, the present dissertation seeks to systematically examine the impact of two types of motivation (i.e., achievement motivation, autonomous motivation) on vigilance performance across four experiments. The present experiments manipulate information processing type, source complexity, and motivational task demands. Three hundred and ninety-eight participants completed either a cognitive task or sensory task, which were psychophysically equated in previous studies (Szalma (&) Teo, 2012; Teo, Szalma, (&) Schmidt, 2011), with or without motivational instructions, and with either low, medium, or high source complexity. Performance measures, perceived stress and workload, and changes to state motivation and engagement at pre-task and post-task are interpreted across three theories of information processing: resource-depletion theory, mind-wandering theory, and mindlessness theory. The results of each of the four studies are discussed in terms of overall support for the resource-depletionist account. The limitations of the present set of experiments and the future directions for research on motivation and sustained attention are also discussed.
Show less - Date Issued
- 2017
- Identifier
- CFE0006582, ucf:51312
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006582
- Title
- Comparing Types of Adaptive Automation within a Multi-Tasking Environment.
- Creator
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Taylor, Grant, Szalma, James, Hancock, Peter, Mouloua, Mustapha, Reinerman, Lauren, University of Central Florida
- Abstract / Description
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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.
Show less - 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
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Fok, Audrey, Mouloua, Mustapha, Hancock, Peter, Szalma, James, Pharmer, James, University of Central Florida
- Abstract / Description
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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.
Show less - Date Issued
- 2015
- Identifier
- CFE0005947, ucf:50797
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005947
- Title
- CROSS-MODAL EFFECTS IN TACTILE AND VISUAL SIGNALING.
- Creator
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Merlo, James, Hancock, Peter, University of Central Florida
- Abstract / Description
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Using a wearable tactile display three experiments were conducted in which tactile messages were created emulating five standard US Army and Marine arm and hand signals for the military commands, namely: "Attention", "Halt", "Rally", "Move Out", and "Nuclear Biological or Chemical event (NBC)". Response times and accuracy rates were collected for novices responding to visual and tactile representations of these messages, which were displayed either alone or together in congruent or...
Show moreUsing a wearable tactile display three experiments were conducted in which tactile messages were created emulating five standard US Army and Marine arm and hand signals for the military commands, namely: "Attention", "Halt", "Rally", "Move Out", and "Nuclear Biological or Chemical event (NBC)". Response times and accuracy rates were collected for novices responding to visual and tactile representations of these messages, which were displayed either alone or together in congruent or incongruent combinations. Results indicated synergistic effects for concurrent, congruent message presentations showing superior response times when compared to individual presentations in either modality alone. This effect was mediated by participant strategy. Accuracy similarly improved when both the tactile and visual presentation were concurrently displayed as opposed to separately. In a low workload condition, participants could largely attend to a particular modality, with little interference from competing signals. If participants were not given instructions as to which modality to attend to, participants chose that modality which was received first. Lastly, initial learning and subsequent training of intuitive tactile signals occurred rapidly with large gains in performance in short training periods. These results confirm the promise for tactile messages to augment visual messaging in challenging and stressful environments particularly when visual messaging is maybe preferred but is not always feasible or possible.
Show less - Date Issued
- 2008
- Identifier
- CFE0002035, ucf:47598
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002035
- Title
- DEINDIVIDUATION OF DRIVERS: IS EVERYONE ELSE A BAD DRIVER?.
- Creator
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MacArthur, Keith, Hancock, Peter, University of Central Florida
- Abstract / Description
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Deindividuation is a psychological phenomenon that occurs when a given environment reduces the "individuality" or identifiability of a person. These environments may cause a psychological reduction in self-consciousness, potentially leading to violations of sociocultural norms (Festinger, Pepitone, & Newcomb, 1952; Singer, Brush, & Lublin, 1965). The present research sought to empirically test deindividuation theory among automobile drivers utilizing the anonymizing factor of observation....
Show moreDeindividuation is a psychological phenomenon that occurs when a given environment reduces the "individuality" or identifiability of a person. These environments may cause a psychological reduction in self-consciousness, potentially leading to violations of sociocultural norms (Festinger, Pepitone, & Newcomb, 1952; Singer, Brush, & Lublin, 1965). The present research sought to empirically test deindividuation theory among automobile drivers utilizing the anonymizing factor of observation. Participants (N = 31) used a driving simulator and were either in the observed condition or an unobserved condition. Analysis of driving data did not reveal significant results, however self-report data had some interesting trends. Though limited in scope, this research begins to shed light on deindividuation of drivers and may provide a foundation for future research.
Show less - Date Issued
- 2014
- Identifier
- CFH0004644, ucf:45325
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004644
- Title
- Destination Image and Tourist's Imagination: The Forgotten Component.
- Creator
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Khalilzadeh, Jalayer, Pizam, Abraham, Fyall, Alan, Tasci, Asli, Hancock, Peter, University of Central Florida
- Abstract / Description
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The objectives of this dissertation was to 1) develop a comprehensive scale to measure visitors' imagination, 2) investigate the structural relationship between imagination and tourism destination image (TDI) components of cognitive, affective, and conative, 3) compare and contrast the various qualities of vividness, richness, saliency, control, and spatial between imagination and prospection, and 4) study the impact of different information sources on the evolving process of prospection to...
Show moreThe objectives of this dissertation was to 1) develop a comprehensive scale to measure visitors' imagination, 2) investigate the structural relationship between imagination and tourism destination image (TDI) components of cognitive, affective, and conative, 3) compare and contrast the various qualities of vividness, richness, saliency, control, and spatial between imagination and prospection, and 4) study the impact of different information sources on the evolving process of prospection to imagination. By conducting four different studies and seven data collection phases, the imagination scale was developed, validated, and utilized to test the proposed structural and differential hypotheses. In study 1, the phenomenology approach was employed and through a series of interviews, the internal experience of the imagination process was extracted. In study 2, which is composed of two focus groups, the potential manifest variables to measure imagination/prospection were developed and the structure of the questionnaire was designed. In study 3, through 3 data collection phases, two versions of long and short imagination scale questionnaire were validated and the structural relationships between imagination and destination image was investigated. In the final study, utilizing experimental design, hypotheses related to five qualities of imagination were compared to those of prospection. Finally, by adopting an exploratory approach, the impact of different information sources on imagination was investigated. The results of this dissertation indicated that the imagination scale is a reliable and valid scale to be used in various hospitality and tourism consumption contexts. It shows a high discriminant validity with TDI and structurally moderates the inter-relationships of the TDI components. In addition, findings of this dissertation support the theoretical discussions on the differences between imagination and prospection. Finally, the results revealed significant distinctions among image, video, and textual information sources regarding their impact on the quality of the mental image.
Show less - Date Issued
- 2018
- Identifier
- CFE0007207, ucf:52279
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007207
- Title
- Detecting Threats from Constituent Parts: A Fuzzy Signal Detection Theory Analysis of Individual Differences.
- Creator
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Van De Car, Ida, Szalma, James, Hancock, Peter, Mouloua, Mustapha, Kennedy, Robert, University of Central Florida
- Abstract / Description
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Signal detection theory (SDT) provides a theoretical framework for describing performance on decision making tasks, and fuzzy signal detection theory (FSDT) extends this description to include tasks in which there are levels of uncertainty regarding the categorization of stimulus events. Specifically, FSDT can be used to quantify the degree to which an event is 'signal-like', i.e., the degree to which a stimulus event can be characterized by both signal and non-signal properties. For instance...
Show moreSignal detection theory (SDT) provides a theoretical framework for describing performance on decision making tasks, and fuzzy signal detection theory (FSDT) extends this description to include tasks in which there are levels of uncertainty regarding the categorization of stimulus events. Specifically, FSDT can be used to quantify the degree to which an event is 'signal-like', i.e., the degree to which a stimulus event can be characterized by both signal and non-signal properties. For instance, an improvised explosive device (IED) poses little threat when missing key elements of its assembly (a stimulus of low, but not zero, signal strength) whereas the threat is greater when all elements necessary to ignite the device are present (a stimulus of high signal strength). This research develops a link between key individual cognitive (i.e., spatial orientation and visualization) and personality (i.e., extroversion, conscientiousness, and neuroticism) differences among observers to performance on a fuzzy signal detection task, in which the items to be detected (IEDs) are presented in various states of assembly. That is, this research relates individual difference measures to task performance, uses FSDT in target detection, and provides application of the theory to vigilance tasks. In two experiments, participants viewed pictures of IEDs, not all of which are assembled or include key components, and categorize them using a fuzzy rating scale (no threat, low threat potential, moderate threat potential, or definite threat). In both experiments, there were significant interactions between the stimulus threat level category and the variability of images within each category. The results of the first experiment indicated that spatial and mechanical ability were stronger predictors of performance when the signal was ambiguous than when individuals viewed stimuli in which the signal was fully absent or fully present (and, thus, less ambiguous). The second study showed that the length of time a stimulus is viewed is greatest when the signal strength is low and there is ambiguity regarding the threat level of the stimulus. In addition, response times were substantially longer in study 2 than in study 1, although patterns of performance accuracy, as measured by the sensitivity index d', were similar across the two experiments. Together, the experiments indicate that individuals take longer to evaluate a potential threat as less critical, than to identify either an absence of threat or a high degree of threat and that spatial and mechanical ability assist decision making when the threat level is unclear. These results can be used to increase the efficiency of employees working in threat-detection positions, such as luggage screeners, provides an exemplar of use of FSDT, and contributes to the understanding of human decision making.
Show less - Date Issued
- 2015
- Identifier
- CFE0006016, ucf:51015
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006016
