@article{park_berman_dodson_liu_armstrong_huang_kaber_ruiz_zahabi_2023, title={Assessing workload in using electromyography (EMG)-based prostheses}, volume={6}, ISSN={["1366-5847"]}, DOI={10.1080/00140139.2023.2221413}, abstractNote={Using prosthetic devices requires substantial cognitive workload. This study investigated classification models for assessing cognitive workload in electromyography (EMG)-based prosthetic devices with various types of input features including eye-tracking measures, task performance, and cognitive performance model (CPM) outcomes. Features selection algorithm, hyperparameter tuning with grid search, and k-fold cross validation were applied to select the most important features and find the optimal models. Classification accuracy, area under the receiver operation characteristic curve (AUC), precision, recall, and F1 scores were calculated to compare models' performance. The findings suggested that task performance measures, pupillometry data, and CPM outcomes, combined with the naïve bayes (NB) and random forest (RF) algorithms, are most promising for classifying cognitive workload. The proposed algorithms can help manufacturers/clinicians predict cognitive workload of future EMG-based prosthetic devices in early design phases.}, journal={ERGONOMICS}, author={Park, Junho and Berman, Joseph and Dodson, Albert and Liu, Yunmei and Armstrong, Matthew and Huang, He and Kaber, David and Ruiz, Jaime and Zahabi, Maryam}, year={2023}, month={Jun} } @article{zahabi_white_zhang_winslow_zhang_huang_kaber_2019, title={Application of Cognitive Task Performance Modeling for Assessing Usability of Transradial Prostheses}, volume={49}, ISSN={["2168-2305"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85063397939&partnerID=MN8TOARS}, DOI={10.1109/THMS.2019.2903188}, abstractNote={The goal of this study was to investigate the use of cognitive modeling to assess the usability of an upper-limb prosthesis with a focus on mental workload responses. Prior studies have investigated usability of upper-limb prostheses with subjective surveys and physiological measures. However, these approaches have limitations, including subject recall of conditions and physiological response contamination by head and body movements and user speech during task performance as well as sensitivity to physical fatigue and room lighting conditions. Cognitive modeling was used to assess mental workload in use of transradial upper-limb prosthesis. A case study was conducted with a participant with upper-limb amputation using two different types of electromyography-based control schemes, including conventional direct control (DC) and pattern recognition (PR) control in order to compare cognitive model outcomes with mental workload assessment using eye-tracking measures. Cognitive models time estimates were also compared with actual task completion time results from the case study to further assess the validity of cognitive modeling as an analytical tool for evaluating upper limb prosthesis usability. Findings of both the cognitive models and case study revealed the PR mode to be more intuitive, reduce cognitive load, and increase efficiency in prosthetic control as compared to the DC mode. Results of the present study revealed that cognitive modeling can be used as an analytical approach for assessing upper-limb prosthetic device usability in terms of workload outcomes. Future studies should validate the present findings with more precise time estimations and a larger user sample size.}, number={4}, journal={IEEE TRANSACTIONS ON HUMAN-MACHINE SYSTEMS}, author={Zahabi, Maryam and White, Melissa Mae and Zhang, Wenjuan and Winslow, Anna T. and Zhang, Fan and Huang, He and Kaber, David B.}, year={2019}, month={Aug}, pages={381–387} } @article{zahabi_kaber_2018, title={Effect of police mobile computer terminal interface design on officer driving distraction}, volume={67}, ISSN={["1872-9126"]}, DOI={10.1016/j.apergo.2017.09.006}, abstractNote={Several crash reports have identified in-vehicle distraction to be a primary cause of emergency vehicle crashes especially in law enforcement. Furthermore, studies have found that mobile computer terminals (MCTs) are the most frequently used in-vehicle technology for police officers. Twenty police officers participated in a driving simulator-based assessment of visual behavior, performance, workload and situation awareness with current and enhanced MCT interface designs. In general, results revealed MCT use while driving to decrease officer visual attention to the roadway, but usability improvements can reduce the level of visual distraction and secondary-task completion time. Results also suggest that use of MCTs while driving significantly reduces perceived level of driving environment awareness for police officers and increases cognitive workload. These findings may be useful for MCT manufacturers in improving interface designs to increase police officer and civilian safety.}, journal={APPLIED ERGONOMICS}, author={Zahabi, Maryam and Kaber, David}, year={2018}, month={Feb}, pages={26–38} } @article{zahabi_kaber_2018, title={Identification of task demands and usability issues in police use of mobile computing terminals}, volume={66}, ISSN={["1872-9126"]}, DOI={10.1016/j.apergo.2017.08.013}, abstractNote={Crash reports from various states in the U.S. have shown high numbers of emergency vehicle crashes, especially in law enforcement situations. This study identified the perceived importance and frequency of police mobile computing terminal (MCT) tasks, quantified the demands of different tasks using a cognitive performance modeling methodology, identified usability violations of current MCT interface designs, and formulated design recommendations for an enhanced interface. Results revealed that “access call notes”, “plate number check” and “find location on map” are the most important and frequently performed tasks for officers. “Reading plate information” was also found to be the most visually and cognitively demanding task-method. Usability principles of “using simple and natural dialog” and “minimizing user memory load” were violated by the current MCT interface design. The enhanced design showed potential for reducing cognitive demands and task completion time. Findings should be further validated using a driving simulation study.}, journal={APPLIED ERGONOMICS}, author={Zahabi, Maryam and Kaber, David}, year={2018}, month={Jan}, pages={161–171} } @article{zahabi_machado_lau_deng_pankok_hummer_rasdorf_kaber_2017, title={Driver performance and attention allocation in use of logo signs on freeway exit ramps}, volume={65}, ISSN={0003-6870}, url={http://dx.doi.org/10.1016/J.APERGO.2017.06.001}, DOI={10.1016/j.apergo.2017.06.001}, abstractNote={The objective of this research was to quantify the effects of driver age, ramp signage configuration, including number of panels, logo format and sign familiarity, on driver performance and attention allocation when exiting freeways. Sixty drivers participated in a simulator study and analysis of variance models were used to assess response effects of the controlled manipulations. Results revealed elderly drivers to demonstrate worse performance and conservative control strategies as compared to middle-aged and young drivers. Elderly drivers also exhibited lower off-road fixation frequency and shorter off-road glance durations compared to middle-aged and young drivers. In general, drivers adopted a more conservative strategy when exposed to nine-panel signs as compared to six-panel signs and were more accurate in target detection when searching six-panels vs. nine and with familiar vs. unfamiliar logos. These findings provide an applicable guide for agency design of freeway ramp signage accounting for driver demographics.}, journal={Applied Ergonomics}, publisher={Elsevier BV}, author={Zahabi, Maryam and Machado, Patricia and Lau, Mei Ying and Deng, Yulin and Pankok, Carl, Jr. and Hummer, Joseph and Rasdorf, William and Kaber, David B.}, year={2017}, month={Nov}, pages={70–80} } @article{zahabi_zhang_pankok_lau_shirley_kaber_2017, title={Effect of physical workload and modality of information presentation on pattern recognition and navigation task performance by high-fit young males}, volume={60}, ISSN={["1366-5847"]}, DOI={10.1080/00140139.2017.1324115}, abstractNote={Abstract Many occupations require both physical exertion and cognitive task performance. Knowledge of any interaction between physical demands and modalities of cognitive task information presentation can provide a basis for optimising performance. This study examined the effect of physical exertion and modality of information presentation on pattern recognition and navigation-related information processing. Results indicated males of equivalent high fitness, between the ages of 18 and 34, rely more on visual cues vs auditory or haptic for pattern recognition when exertion level is high. We found that navigation response time was shorter under low and medium exertion levels as compared to high intensity. Navigation accuracy was lower under high level exertion compared to medium and low levels. In general, findings indicated that use of the haptic modality for cognitive task cueing decreased accuracy in pattern recognition responses. Practitioner Summary: An examination was conducted on the effect of physical exertion and information presentation modality in pattern recognition and navigation. In occupations requiring information presentation to workers, who are simultaneously performing a physical task, the visual modality appears most effective under high level exertion while haptic cueing degrades performance.}, number={11}, journal={ERGONOMICS}, author={Zahabi, Maryam and Zhang, Wenjuan and Pankok, Carl and Lau, Mei Ying and Shirley, James and Kaber, David}, year={2017}, pages={1516–1527} } @article{kaber_zahabi_2017, title={Enhanced Hazard Analysis and Risk Assessment for Human-in-the-Loop Systems}, volume={59}, ISSN={["1547-8181"]}, DOI={10.1177/0018720817693357}, abstractNote={Objective: The objective of this study was to enhance the existing system hazard analysis (SHA) technique by introducing the concepts of human and automation reliability quantification as well as fuzzy classification of system risks. These enhancements led to formulation of a new overall system risk-reliability score. Background: Many system safety analysis methods focus on individual physical component failure. Some human reliability analyses (HRA) consider human-automation interaction in determining system failure rates. There is no system safety analysis technique that quantifies the impact of human and automation reliability on the risk of hazard exposure. Method: Classification of the probability and severity of hazard exposure is typically made in terms of linguistic rather than numerical variables. Fuzzy sets are applicable for transforming linguistic classifications to numerical quantities. We focused on using fuzzy sets to define overlapping bands of system risk exposure with reference to the hazard risk categories defined in MIL-STD 882B. Fuzzy sets were also used for human-automated system reliability classification. Results: Introduction of human and automation reliability assessment in the SHA allows for definition of a system risk-reliability modeling space. The enhanced SHA (E-SHA) technique yields a mishap risk index, which is projected based on a composite assessment of human-automated system reliability at the time of operation. The E-SHA was compared with one of the most advanced HRA techniques. Conclusion: The E-SHA technique supports broader safety control recommendations and provides comparable, if not more detailed, results than prior systems safety and HRA techniques.}, number={5}, journal={HUMAN FACTORS}, author={Kaber, David and Zahabi, Maryam}, year={2017}, month={Aug}, pages={861–873} } @article{zahabi_pankok_kaber_machado_lau_hummer_rasdorf_2017, title={On-Road Visual Sign Salience, Driver Attention Allocation, and Target Detection Accuracy}, ISSN={["2169-4052"]}, DOI={10.3141/2663-06}, abstractNote={Previous studies have empirically assessed the effect of on-road signage on driver distraction and attention allocation through eye-tracking measures and driving simulations. However, state and federal agencies might be able to make use of simpler approaches to determining the potential visual load of on-road signs. This study compared different on-road signage (food, gas and attraction, and distance guide signs) with respect to visual salience, assessed the effect of the number of panels and logo format on signage salience, and analyzed associations between salience values for different sign types with target detection accuracy and off-road glance duration. Visual salience of signs was measured with the salience using the natural statistics (SUNs) method. For correlation analyses between sign salience, attention allocation, and detection accuracy, a sample of 120 drivers participated in two driving simulation studies. Results revealed food business signs, containing all pictorial logos, to be more salient than gas and attraction and distance guide signs. In addition, results revealed that increasing the number of sign panels from six to nine significantly increased visual salience. It was also found that attraction signs including all pictorial logos were more salient than signs with text-based logos. Results did not reveal statistically significant relationships between visual salience and attention allocation. In addition, there was no significant correlation between target detection accuracy and visual salience for various sign types. Future work with a higher sign-sampling rate is needed to assess whether the SUNs method is a useful measure for determining if roadway sign salience is a driving factor in distraction.}, number={2663}, journal={TRANSPORTATION RESEARCH RECORD}, author={Zahabi, Maryam and Pankok, Carl, Jr. and Kaber, David B. and Machado, Patricia and Lau, Mei Ying and Hummer, Joseph E. and Rasdorf, William}, year={2017}, pages={40–47} } @article{zahabi_machado_pankok_lau_liao_hummer_rasdorf_kaber_2017, title={The role of driver age in performance and attention allocation effects of roadway sign count, format and familiarity}, volume={63}, ISSN={0003-6870}, url={http://dx.doi.org/10.1016/J.APERGO.2017.04.001}, DOI={10.1016/j.apergo.2017.04.001}, abstractNote={White-on-blue logo signs are used to inform drivers of food, gas, lodging, and attraction businesses at highway interchanges. In this study, 60 drivers were asked to look for food and attraction targets on logo signs while driving in a realistic freeway simulation. The objective of the study was to quantify effects of the number of sign panels (six vs. nine), logo familiarity (familiar vs. unfamiliar), logo format (text vs. pictorial), and driver age (young, middle, and elderly) on performance, attention allocation and target identification accuracy. Results revealed elderly drivers to exhibit worse performance in comparison to middle-age and young groups even though they adopted a more conservative driving strategy. There was no significant effect of the number of panels, logo familiarity, and logo format on driver performance or attention allocation. In target identification, drivers were more accurate with familiar or text-based panels appearing in six-panel signs.}, journal={Applied Ergonomics}, publisher={Elsevier BV}, author={Zahabi, Maryam and Machado, Patricia and Pankok, Carl, Jr. and Lau, Mei Ying and Liao, Yi-Fan and Hummer, Joseph and Rasdorf, William and Kaber, David B.}, year={2017}, month={Sep}, pages={17–30} } @inproceedings{zhang_white_zahabi_winslow_zhang_huang_kaber_2016, title={Cognitive workload in conventional direct control vs. pattern recognition control of an upper-limb prosthesis}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85015802131&partnerID=MN8TOARS}, DOI={10.1109/smc.2016.7844587}, abstractNote={The purpose of this study was to compare the cognitive workload of able-bodied individuals when using a myoelectric prosthetic under direct control (DC) or electromyography pattern recognition (PR) control. Different from existing clinical evaluations involving dual-task performance, pupillography measured with an eye-tracking system was used to quantitatively assess user cognitive workload in using a 2 degree-of-freedom prosthesis for a clothespin task. Test results revealed the PR control to produce superior task performance and to require lower cognitive load than demanded of participants under the DC condition. This study provided evidence of both performance and workload advantages of PR control over DC control. PR control was more intuitive to the prosthesis user and, therefore, required less cognitive effort. Furthermore, the study identified a new effective measure of cognitive workload in upper limb prosthesis use via pupillography.}, booktitle={Ieee international conference on systems man and cybernetics conference}, author={Zhang, W. J. and White, M. and Zahabi, M. and Winslow, A. T. and Zhang, F. and Huang, He and Kaber, D.}, year={2016}, pages={2335–2340} } @inproceedings{zahabi_zhang_pankok_lau_shirley_kaber_2016, title={Effect of physical workload on navigation task performance by high-fit young males}, DOI={10.1109/smc.2016.7844265}, abstractNote={Many occupations require both physical exertion and the ability to navigate in an environment, simultaneously. This study investigated how intensity of physical activity influences direction determination and distance estimation. Thirty high fit young males participated in a lab study. Results showed that while high fit young males were accurate in determining direction across levels of physical exertion, they were significantly less accurate in distance estimation under high exertion intensity. Although physical activity level did not influence direction determination accuracy, response time was significantly shorter when participants were subject to low physical loading in comparison to medium and high loading. In addition, we found that distance estimation response time increased as physical workload increased. Findings of this study can be used to enhance presentation of navigation information in occupations that require concurrent physical activity and navigation.}, booktitle={Ieee international conference on systems man and cybernetics conference}, author={Zahabi, M. and Zhang, W. J. and Pankok, C. and Lau, M. Y. and Shirley, J. and Kaber, D. B.}, year={2016}, pages={350–354} } @article{kaber_jin_zahabi_pankok_2016, title={The effect of driver cognitive abilities and distractions on situation awareness and performance under hazard conditions}, volume={42}, ISSN={["1873-5517"]}, DOI={10.1016/j.trf.2016.07.014}, abstractNote={The objective of this study was to investigate the role of cognitive abilities in driver situation awareness (SA) and performance. Sixteen participants drove a high-fidelity driving simulator and experienced a hazard condition (a vehicle turning into their lane). In general, exposure to the hazard resulted in a subsequent increase in driver SA in follow-on driving. Working memory and visual-cognitive skills appeared to be critical to supporting driver SA after hazard exposure. Findings indicated that tactical driving tasks place greater demands on cognitive abilities and levels of SA for successful performance, as compared to operational and strategic tasks. Correlations among measures of driver cognitive ability, SA and performance provide a basis for future development of a relational model of the roles of cognition and SA in driving.}, journal={TRANSPORTATION RESEARCH PART F-TRAFFIC PSYCHOLOGY AND BEHAVIOUR}, author={Kaber, David and Jin, Sangeun and Zahabi, Maryam and Pankok, Carl, Jr.}, year={2016}, month={Oct}, pages={177–194} } @article{pankok_zahabi_zhang_choi_liao_nam_kaber_2017, title={The effects of interruption similarity and complexity on performance in a simulated visual-manual assembly operation}, volume={59}, ISSN={["1872-9126"]}, DOI={10.1016/j.apergo.2016.08.022}, abstractNote={The objective of the study was to assess the effects of interruption task similarity and complexity on performance of a simulated industrial assembly operation. Eighteen participants performed a simulated industrial assembly operation, including one trial with no interruption and eight others presenting an interruption task. Interruption conditions comprised a full crossing of task similarity to the primary assembly operation (similar, dissimilar) and complexity (simple, complex) with replication for each participant. Order of condition presentation was randomized. Findings revealed greater time to return to primary visual-manual assembly performance after a similar task interruption. Results also indicated complex interruptions may promote cognitive arousal that increases productivity following assembly interruptions. The majority of results are explained in terms of the Activation-Based Memory for Goals model. Findings provide some guidance for interruption management protocol design for workers engaged in procedural visual-manual assembly operations.}, journal={APPLIED ERGONOMICS}, author={Pankok, Carl, Jr. and Zahabi, Maryam and Zhang, Wenjuan and Choi, Inchul and Liao, Yi-Fan and Nam, Chang S. and Kaber, David}, year={2017}, month={Mar}, pages={94–103} } @article{zahabi_kaber_swangnetr_2015, title={Usability and Safety in Electronic Medical Records Interface Design: A Review of Recent Literature and Guideline Formulation}, volume={57}, ISSN={["1547-8181"]}, DOI={10.1177/0018720815576827}, abstractNote={Objective The objectives of this study were to (a) review electronic medical record (EMR) and related electronic health record (EHR) interface usability issues, (b) review how EMRs have been evaluated with safety analysis techniques along with any hazard recognition, and (c) formulate design guidelines and a concept for enhanced EMR interfaces with a focus on diagnosis and documentation processes. Background A major impact of information technology in health care has been the introduction of EMRs. Although numerous studies indicate use of EMRs to increase health care quality, there remain concerns with usability issues and safety. Method A literature search was conducted using Compendex, PubMed, CINAHL, and Web of Science databases to find EMR research published since 2000. Inclusion criteria included relevant English-language papers with subsets of keywords and any studies (manually) identified with a focus on EMR usability. Results Fifty studies met the inclusion criteria. Results revealed EMR and EHR usability problems to include violations of natural dialog, control consistency, effective use of language, effective information presentation, and customization principles as well as a lack of error prevention, minimization of cognitive load, and feedback. Studies focusing on EMR system safety made no objective assessments and applied only inductive reasoning methods for hazard recognition. Conclusion On the basis of the identified usability problems and structure of safety analysis techniques, we provide EMR design guidelines and a design concept focused on the diagnosis process and documentation. Application The design guidelines and new interface concept can be used for prototyping and testing enhanced EMRs. }, number={5}, journal={HUMAN FACTORS}, author={Zahabi, Maryam and Kaber, David B. and Swangnetr, Manida}, year={2015}, month={Aug}, pages={805–834} }