bluuebunny/crossref_metadata_2025 huggingface dataset:
Usability in Health IT
Authors: Fairbanks Rollin J. (Terry) , Bisantz Ann , Hettinger A. Zachary , Ratwani Raj , Patterson Emily , Roth Emilie
Published: September 2016

The relatively rapid transition from a paper-based system to a digital system in healthcare has not always employed a sophisticated integration of usability concepts. Yet usability is critical to safety and to effectiveness of the electronic health record, and regulators and policy makers have been increasingly focused on this area. This panel will provide a variety of perspectives on this important issue, ranging from a description of the problem based on current vendor usability practices; recommendations regarding domain content rich usability processes including use cases, assessments, and scenarios; and the extension of usability assessments and design improvements to post-system implementation.
Promoting Patient Safety with Human Factors Methods
Authors: Reale Carrie , Saleem Jason J. , Patterson Emily S. , Hettinger Aaron Zachary , Anders Shilo , Miller Anne
Published: September 2016

Medication management is a complex and mentally demanding endeavor performed by multiple individuals in diverse settings and at variable points in time. Achieving the goal of safe care delivery with optimized patient outcomes requires ongoing communication, coordination, and interaction between an array of technologies and roles across the health care continuum. Human factors principles and methods have the potential to substantially improve patient safety throughout this high-risk cycle. The purpose of this interactive discussion panel is to explore the medication management process from a sociotechnical perspective to identify specific challenges and vulnerabilities, and recommend strategies that leverage human factors processes and design principles to efficiently and effectively address safety critical issues.
Patient Work as a Maturing Approach Within HF/E
Authors: Valdez Rupa S. , Holden Richard J. , Caine Kelly , Madathil Kapil , Mickelson Robin , Lovett Novak Laurie , Werner Nicole
Published: September 2016

Over the last five years, human factors and ergonomics (HF/E) applications in healthcare have expanded beyond the institution to encompass the homes and communities of patients. The patient work approach has been developed as a means of formalizing the theoretical and methodological foundations of applying HF/E within this new domain. Early applications of the patient work approach were confined to studies of relatively straightforward self-management tasks. As the patient work approach matures, however, its application is spreading to more complex subdomains of health management in home and community settings. This panel will focus on cutting edge application and methodological areas of patient work. Each panelist will introduce their work, present challenges related to expanding the patient work approach in a new direction, and engage with audience members to address these challenges and brainstorm ways in which the patient work approach can be further adapted to more intricate healthcare challenges.
Development of a Baseline Workload Model for Future Submarine Sonar Crewing Analysis
Authors: Wang Wenbi
Published: September 2016

A computational human performance model was developed to analyze sonar operator workload using the legacy sonar system on the Royal Canadian Navy’s Victoria-Class Submarine. The paper describes key components of the model, including a task network for representing operator activities, the Visual, Auditory, Cognitive and Psychomotor (VACP) algorithm for characterizing task demand, and a discrete-event simulation for predicting operator workload. Results from a simulation experiment revealed high levels of task demand imposed by the adopted mission scenario and an uneven distribution of workload among four sonar operators under a specific contact assignment scheme. The results establish a set of performance benchmarks that will be used for evaluating workload predictions made by a future model of a new sonar system, supporting quantifiable assessment of crewing options for the future sonar system.
Assessing Pilot Workload in Single-Pilot Operations with Advanced Autonomy
Authors: Stimpson Alexander J. , Ryan Jason C. , Cummings Mary L.
Published: September 2016

The proposed transition to single-pilot operations (SPO) in commercial and military aircraft has motivated the development of advanced autonomy systems. However, a detailed analysis of the impact of advanced autonomy on pilot workload through various phases of flight and contingency scenarios has not been conducted. To this end, this paper presents the development of the Pilot-Autonomy Workload Simulation (PAWS), a discrete event simulation model that allows the investigation of pilot workload under a variety of advanced autonomy capabilities and scenarios. Initial utilization results from PAWS of nominal and off-nominal point-to-point missions demonstrate that the workload for a single pilot assisted by advanced autonomy varies considerably over different phases of flight and various contingencies. These results suggest that advanced autonomy to offset pilot workload is not needed for low-workload phases, but could be critical during periods of high workload.
A Rested Development
Authors: Fercho Kelene A. , Peterson Doug , Baugh Lee A.
Published: September 2016

The effects of task-induced cognitive fatigue on performance, strategy, and P300 event-related potentials (ERPs) were examined. Fatigue was induced by task load with participants completing either 700 mental rotation trials with (high fatigue) or without (low fatigue) a secondary task to increase fatigue. No differences were found between groups when examining mental rotation task decision accuracy or strategy; however, the number of trials in which the participant’s total trial time was greater than twice their average was influenced by experimental manipulations designed to increase task difficulty. These ‘minibreaks’, referred to as blocking, may have served to regulate effort expenditure in order to preserve task performance. P300 peak amplitude differed between groups, with high blocking participants showing a reduced amplitude and more dispersed P300 topology compared to low blockers. These results provide compelling evidence that performance outcome may not be affected by task demands if a compensatory effort strategy is utilized.
Using Pupillometry to Indicate the Cognitive Redline
Authors: Rodriguez-Paras Carolina , Yang Shiyan , Ferris Thomas K.
Published: September 2016

Physiological measures, which are influenced by the arousal of the autonomous nervous system, have been studied as indicators of extreme levels of mental workload that approach or exceed the cognitive “redline”, the point at which task demand exceeds the supply of cognitive resources. In response to increasing task demands, measures such as heart rate variability show asymptotic patterns in arousal that are consistent with plateau patterns in subjective self-reported measures. This suggests potential to use physiological indicators in real time to predict when an operator is at increased risk of cognitive overload. Expanding on prior work, the current study examined pupil diameter as a new potential indicator of the cognitive redline in a multitask environment created with the Multi-Attribute Task Battery-II (MATB-II). Results showed that pupil diameter is sensitive to imposed mental workload and exhibits a similar asymptotic pattern that may provide another potential real-time indicator of the cognitive redline.
Disconnects in design and infection prevention and control – how the design of products and the environment in neonatal intensive care may be undermining infection prevention practice
Authors: Trudel Chantal , Cobb Sue , Momtahan Kathryn , Brintnell Janet , Mitchell Ann
Published: September 2016

This study examined the role design plays in infection prevention and control within an existing neonatal intensive care unit. Methods from human-centred design such as planning, stakeholder meetings and naturalistic observation were used to obtain infection prevention information related to the existing unit design, interactions with products and the environment, and perspectives of front-line staff on design. Thematic analysis was used to categorize and structure the issues that were identified.

The analysis revealed that the design of products and the environment may be undermining best practice in infection prevention. Health care workers experience a variety of difficulties in maintaining the recommended barriers to infection transmission, difficulties which stem from deficiencies in products and the environment. Various aspects of the neonatal care design lack the feedback or supports needed to help health care workers differentiate or work between infection transmission zones making the design challenging to use or maintain in a manner that supports best practice in infection prevention. Identifying issues in the design of products and the environment related to infection prevention practice led to the development of a ‘Design Exploration Guide’. The guide outlines issues and strategies for remediation based on feasibility within the project constraints.
Exploring Psycho-Physiological Correlates to Trust
Authors: Khalid Halimahtun M. , Shiung Liew Wei , Nooralishahi Parham , Rasool Zeeshan , Helander Martin G. , Kiong Loo Chu , Ai-vyrn Chin
Published: September 2016

This paper describes a methodology for exploring trust using psychological (subjective) and physiological (objective) correlates to trust. The aim was to explore trust using natural dialogs of real-world scenarios that embed fifteen subjective measures. The goal was to apply the method in modeling human-robot-human interaction, involving three types of androids and to predict trust. Two forms of dialogs were employed: a guided script and a predetermined dialog representing three social scenarios. Objective features included facial expressions, voice and heart rate. Subjective trust measures comprised ability, benevolence and integrity. A repeated measures experimental design was employed. Forty-two subjects participated in the study. The data was analyzed using exploratory factor analysis and correlation. Multiple neuro-fuzzy models were trained using the data set and combined as an ensemble using evolutionary algorithms. The final ensemble estimated trust with 67% accuracy. The implications of the findings and limitations of the method are discussed.
Investigating a Non-Invasive Method of Measuring the Quality of Latent Hazard Schemas of Novice Teen and Experienced Adult Drivers
Authors: Katrahmani Atefeh , Romoser Matthew , Samuel Siby
Published: September 2016

The main objective of this study was to investigate the development of a non-invasive tool for assessing the quality of a driver’s latent hazard schema. Verbal and eye tracking protocols were mapped to Endsley’s model of situation awareness (SA) as a means of measuring schema development. Participants were asked to drive a simulator with various hazard scenarios. Verbal protocol results showed that teenswere less likely to verbally associate subtle cues and accurately state what ‘could happen’. The verbal protocols of teens consisted primarily of simple statements of what was happening and what they were currently doing. Whereas, experienced drivers’ verbal protocols indicated higher levels of processing of the driving environment and contained projections of what could happen. In mapping driver commentary and eye glances for potential hazards in which the hazardous element is hidden from view, experienced adult drivers achieved overall higher level of situation awareness than teen drivers.
Spectral Power Analysis of Drivers’ Gas Pedal Control during Steady-state Car-following on Freeways
Authors: Feng Fred , Bao Shan , Sayer James , LeBlanc David
Published: September 2016

This paper investigated the frequency characteristics of drivers’ gas pedal control in steady-state car-following on freeways by using vehicle sensor data from an existing naturalistic driving study. The main objectives were to examine the frequency range and distributions of a driver operating the gas pedal when following a lead vehicle, and whether the higher and lower frequency components of the gas pedal signal would vary when following a lead vehicle with varying distances. A total of 1,461 driving segments each with 90-seconds of steady-state freeway car-following were extracted from the naturalistic driving data. Fourier analysis was performed to convert the time series data of drivers’ gas pedal control to the frequency domain. The results show that during steady-state freeway car-following, the power of the gas pedal control peaks at around 0.033 Hz or 15 s per pedal movement (derived using the median of the peak frequency), and the upper limit of the frequency is around 0.94 Hz or 0.5 s per pedal movement (derived using the 95th percentile of the cutoff frequency). Further analysis showed that following a lead vehicle with smaller gap was associated with a larger proportion of the higher frequency component ( p < .001), and following a lead vehicle with larger gap was associated with a larger proportion of the lower frequency component ( p < .001). This suggests that the larger gap may allow the driver to relax control of the gas pedal with smoother operation. Potential applications of this paper include developing more realistic driver models that could be used in designing advanced driver assistance systems.
Evaluating the Relationship between Team Performance and Joint Attention with Longitudinal Multivariate Mixed Models
Authors: Tolston Michael T. , Strang Adam J. , Funke Gregory J. , Miller Brent , Brown Rebecca , Menke Lauren
Published: September 2016

Previous research indicates that measures of joint attention provide unique insight into team cognition and performance. In this study, we examined the effects of practice and joint attention on team performance improvement using multivariate mixed models, with an emphasis on exploring the correlation structure between the variances in growth trajectories of team performance and joint attention around estimated means. Observed patterns in team performance showed time dependent trends well known in a variety of learning contexts, including non-linear growth, performance retention, and performance retention loss between multiple practice sessions. Joint attention was found to decrease non-linearly over time, starting out comparatively high and decreasing as a function of time on task. Additionally, we found evidence of negative relationships between joint attention and team performance in our task environment, and we established that joint attention was significantly higher than the chance levels that would be expected by task-constraints alone.
Influence of Speed in Whole Body Vibration Exposure in Heavy Equipment Mining Vehicles
Authors: Marin Luz S. , Rodriguez Andrés , Rey Estefany , Barrero Lope H. , Dennerlein Jack , Johnson Pete W.
Published: September 2016

This study aimed to characterize and contrast the ISO 2631-1 daily average-continuous A(8) and cumulative-impulsive VDV(8) whole body vibration (WBV) exposures during the operation of mining heavy equipment vehicles (HEVs). In a cross-sectional study, WBV measurements were collected from six different types of HEVs. For each HEV, the daily A(8) and VDV(8) WBV exposures were determined for each axis (x, y and z) along with the vector sum (∑xyx).. The predominant axis of vibration exposure was related to and dependent on the type of HEV, which all have different average speeds. Most of the predominant axis WBV exposures were above the ISO daily vibration action limits and the vector sum-based WBV exposures were considerably higher. Our results indicated that mining HEV operators are exposed to high levels of both continuous and impulsive WBV exposures, with the impulsive WBV exposures being more restrictive with respect the HEVs daily maximum operation hours.
The Comparisons of Whole Body Vibration Exposures and Supporting Musculature Loading between Single- and Multi-axial Suspension Seats during Agricultural Tractor Operation
Authors: Kim Jeong Ho , Dennerlein Jack T , Johnson Peter W
Published: September 2016

Due to rough terrain, agricultural tractor drivers are likely exposed to a high level of whole body vibration, especially impulsive shocks. These WBV exposures are often predominant in the fore-aft (x) or lateral (y) axis. However, the current industry standard seats are designed to reduce mainly vertical (z) axis WBV exposures, and therefore, may be less effective in reducing tractor drivers’ exposure to WBV. Therefore, in a repeated-measures design with 11 subjects, this study evaluated efficacy of a multi-axial (vertical + lateral) suspension seat in reducing WBV exposure and low back (erector spinae) muscle activity relative to an industry standard single-axial suspension seat. The results showed that while there was no difference in fore-aft (x) and vertical (z) axis WBV exposures between the seats, the multi-axial suspension seat had lower A(8) lateral (y) WBV exposures [median (interquartile range): 0.7 (0.41, 0.83) m/s2] and VDV(8) [13.5 (7.4, 16.4) m/s1.75] WBV exposures than the single-axial suspension seats [ A(8): 0.81 (0.48 0.93) m/s2; VDV(8): 13.5 (8.7, 18.5) m/s1.75] (p = 0.02 and 0.04, respectively). Low back muscle activity was also lower on the multi-axial suspension seats, however this difference was not significantly significant. These results indicate that mu the multi-axial suspension may have potential to reduce the WBV exposures and muscular loading on low back among agricultural vehicle operators.
Comparing the Whole Body Vibration Exposures across Three Truck Seats
Authors: Wang Fangfang , Davies Hugh , Du Bronson , Johnson Peter W.
Published: September 2016

Studies have shown that there are differences in whole body vibration (WBV) exposures and WBV attenuation performance among different suppliers of air suspension truck seats. With 17 truck drivers operating semi-trucks over two common road types (the same highways and dirt roads), WBV exposures were measured and compared across three different air-suspension truck seats. Similar to a previous study, in the higher-speed, on-road highway conditions, one seat was found to have higher WBV exposures and lower WBV attenuation performance. In off-road conditions at slower speed, there were negligible differences across the three seats. These differences in seat performance have important practical implications. The higher performing seats nearly doubled the amount of time drivers could operate their trucks before reaching the ISO daily vibration action limits from 3 to 6 hours a day to 9 to 11 hours a day. Seat suspension-based design differences are thought to account for the performance differences.
Trunk Posture Influences Neck Angle When Reading A Tablet Computer
Authors: Gallagher Kaitlin M. , Douglas Ethan C.
Published: September 2016

In 2013, 64% of American households owned a handheld computer device (e-reader, tablet, smartphones, etc.). The presence of these devices has grown more quickly than our understanding of their effects on musculoskeletal disorders. Their use on a tabletop or a person’s lap causes increased head and neck flexion, as well as an inreased gravitational moment produced by the weight of the head (Straker et al., 2009, Young et al., 2012, Vasavada et al., 2015). A limitation to these studies is that they keep a standard trunk position throughout all tasks; however, people can also assume a semi-reclined position when reading a tablet. The purpose of this study was to determine the influence of a semi-reclined trunk position on neck and head flexion angle, and cervical erector spinae muscle activity. Nineteen participants (10 male, 9 female) read off of a tablet in four postures: with the tablet in their lap, on a tabletop, off of a standard computer monitor, and semi-reclined to an angle of 30 degrees from the vertical. Having the tablet on the lap ( M=16%MVC, SD=8%MVC) significantly increased muscle activity of the cervical erector spinae ( p=.0023) compared to reading off of a monitor or in the semi-reclined position (approximately 10%MVC). Neck and head flexion angles significantly increased ( p<.001) when reading the tablet off the lap (neck M=56.8o, SD=17.3o; head M=53.4o, SD=12.9o) versus the computer (neck M=6.4o, SD=6.4o; head M=8.2o, SD=7.4o), however, the head angle during semi-reclined reading stayed more vertical despite having the highest increase in neck flexion angle (neck M=71.6o, SD=14.0o; head M=19.7o, SD=9.2o). In the semi-reclined position, the gravitational moment of the head is second smallest for the four reading positions. In theory, this is desired as the moment that must be produced by the musculature and surround tissues would be less. The downside to this posture is that many of the neck extensor muscles may still not be in optimal force and moment production position. Many of the neck muscles that assist with extension originate from C5 to T5 and insert on C5 and above (Vasavada et al., 1998). At 30 degrees of neck flexion, the moment generating capability of the spenius and semispinalis muscles are decreased compared to when at a neutral position and fascicle length of splenius cervicis, capitis, and semispinalis capitis muscles experience changes of more than 70% of optimal length (Vasavada et al., 1998). While many of the extensor muscles only show moment arms that vary by 1 cm or less, for some there can be about a 2-3 cm changes as one goes from a flexed to extended neck posture (Vasavada et al., 1998). These combined changes mean that the force producing capabilities of the neck extensor muscles may be compromised a semi-reclined position. Future studies should report torso angle to properly analyze biomechanical risk factors during handheld computer use and compare results between studies.
Obesity effect on isometric strength of the trunk extensors
Authors: Pajoutan Mojdeh , Mehta Ranjana K. , Cavuoto Lora A.
Published: September 2016

Trunk muscle strength could contribute to overexertion and falls related back injuries. With obesity, greater trunk extensor muscle is expected to overcome the additional mass especially those accumulated in the abdomen area. The objective of this study was to investigate the extent of obesity effect on maximum trunk extensor muscles’ capacity. 33 females and 35 males in three age-matched groups of normal weight, overweight, and obese completed four replications of three repeated maximum voluntary isometric contractions (MVICs) of trunk extensor muscles. Obesity impairment was evident in the strength per kilogram body mass (BM) and fat-free mass (FFM). FFM and age explained 60% of the variability of the trunk strength. The findings of this study suggest an inferior performance with obesity in complex tasks requiring high intensity strengths.
The Concavity Index
Authors: Salar Menekse , Sesek Richard F. , Schall Mark C.
Published: September 2016

Low back pain (LBP) is one of the most common musculoskeletal disorders facing the working world. Most LBP studies focus on exposure to physical risk factors in the workplace such as lifting, pushing, pulling and awkward postures. Unfortunately, many of these studies do not consider personal risk factors. Several studies have observed that personal characteristics ssuch as age and gender are predictive of LBP. However, studies that focus on MRI characteristics of the disc structure and the relationship between lumbar discs and personal characteristics are very rare. For this study, T2-weighted MRI scans were obtained from 50 subjects (25 females & 25 males) whose age ranged from 20-40 years (mean 31.12 years, SD ± 5.4) without any self-reported chronic episodes of low back pain. The MRI scans contain the sagittal profile of lumbar endplates (L2-S1). Each examiner measured the height and the concavity levels of the lumbar discs. These measures were used to calculate a Concavity Index (CI; concavity level divided by vertebral body height). CIs were compared to Pfirrmann IVD grading scores to evaluate their agreement and compare their respective inter-observer reliabilities. A higher CI is hypothesized to be indicative of spinal degradation and subsequent low back pain. Gender differences were observed for CIs at all levels, particularly for the L5-S1. A linear relationship between average CI and corresponding Pfirrmann classification was observed. While overall agreement among Pfirrmaann raters was high, 10% of ratings disagreed by two or more categories. CIs had an average coefficient of variation of just 0.95% across all participants and lumbar regions. This work presents an alternative method for quantifying intervertebral disc degeneration that appears to have advantages over the traditional Pfirrmann grading scale.
Discussion Panel on Computer Vision and Occupational Ergonomics
Authors: Radwin Robert G. , Lee SangHyun , Li Kang , Lieblich Max , Daniel Park Byoung-keon
Published: September 2016

Computer vision has already impacted a diverse field of applications, ranging from industrial robotics, intelligent and autonomous vehicles, security surveillance, manufacturing inspection, and human-computer interaction. Furthermore, digital imaging technologies are advancing ever smaller in size, finer in granularity, and faster in processing, while becoming less expensive and thus more accessible to businesses, organizations, and individuals in devices such as smart phones and tablets. Consumer products such as the Kinect™ offer advanced marker-less 3D motion capture capabilities at a low cost. New computer vision methods are now being researched and developed for occupational ergonomics applications. It is anticipated that these new tools will profoundly impact the future of occupational ergonomics and provide a variety of new instruments and techniques for design, analysis and evaluation in the practice of ergonomics. A panel of leading experts will describe some of the cutting edge research they are pursuing utilizing computer vision for occupational ergonomics applications. Radwin, Lee and Li use algorithms that track pixel patterns recorded from conventional video for quantifying repetitive hand motion, manual lifting and whole-body activities. Lee and Li describe the use computer vision tools to predict joint angles for a whole-body link model. Lieblich and Park describe the use of Kinect™ for classifying postures and generating individualized task specific avatars. Each of these approaches has specific advantages and limitations, which will be addressed by the panel. A discussion will follow exploring future research needs as well as engaging in a discussion among panelists and attendees about the needs, limitations, and obstacles that this new technology faces in bringing it into practice.
Comparative Analysis of Inertial Sensor to Optical Motion Capture System Performance in Push-Pull Exertion Postures
Authors: Lim Sol , Case Andrea , D’Souza Clive
Published: September 2016

This study examined interactions between inertial sensor (IS) performance and physical task demand on posture kinematics in a two-handed force exertion task. Fifteen male individuals participated in a laboratory experiment that involved exerting a two-handed isometric horizontal force on an instrumented height-adjustable handle. Physical task demand was operationalized by manipulating vertical handle height, target force magnitude, and force direction. These factors were hypothesized to influence average estimates of torso flexion angle measured using inertial sensors and an optical motion capture (MC) system, as well as the root mean squared errors (RMSE) between instrumentation computed over a 3s interval of the force exertion task. Results indicate that lower handle heights and higher target force levels were associated with increased torso and pelvic flexion in both, push and pull exertions. Torso flexion angle estimates obtained from IS and MC did not differ significantly. However, RMSE increased with target force intensity suggesting potential interactive effects between measurement error and physical task demand.
Sickness behaviors (reduced social interaction and pain behaviors) are linked to inflammatory mechanisms in a rat model of work-related musculoskeletal disorders
Authors: Barbe MF , Xin DL , Hadrévi J , Elliott ME , Barr-Gillespie AE
Published: September 2016

We sought to determine if sickness behaviors (decreased social interaction and pain) are induced in a rat model of work-related overuse and effectiveness of anti-inflammatory treatments. Rats first trained to learn a high force reaching task (15 min/week day for 6 wks), with subsets treated prophylactically with ibuprofen or anti-TNFalpha. Others performed a high repetition high force (HRHF) task for 6 or 12 weeks (2 hrs/day, 3 days/wk) untreated, or with ibuprofen, anti-TNFalpha or rest treatments beginning task week 5. Untreated HRHF rats had increased IL-1beta, IL-6 and TNFalpha in serum and brain, increased Substance P in spinal cord, decreased social interaction and increased forepaw allodynia. Secondary anti-inflammatory treatments attenuated social interaction and brain changes, but not allodynia or spinal cord changes; rest provided partial attenuation. Prophylactic treatments prevented all changes. Thus, inflammatory mechanisms mediate the development of sickness behaviors induced by work-related overuse, but not maintenance of allodynia.
Relationships between Lower Extremity Musculoskeletal Disorders Symptoms and Tibial Acceleration Measures in Distribution Center Workers
Authors: Dutt Mohini , Lavender Steven A. , Sommerich Carolyn M. , Chaudhari Ajit M.W.
Published: September 2016

In a survey of 341 workers, we have found lower extremity musculoskeletal symptoms to be prevalent in distribution center employees working in material handling jobs. This study was a cross-sectional field study aimed at developing risk models showing associations between tibial acceleration and lower extremity musculoskeletal disorder symptoms. One hundred thirty two participants volunteered to wear uni-axial accelerometers that quantified their bilateral tibial acceleration exposures during two hours of normal work activities and also completed a questionnaire assessing individual factors and their experience with lower extremity musculoskeletal symptoms. The questionnaire and accelerometer data were used to develop logistic regression models exploring the relationships between the likelihood of self-reported lower extremity symptoms in the hip/thigh, knee, and ankles/feet and relevant biomechanical and individual exposure variables. An outcome score was created by multiplying the symptom frequency score by the symptom severity score by the therapy score for both the knees and the ankles/feet regions. Only the symptom frequency and severity scores were multiplied to create the hip/thigh outcome score. Multiple logistic regression models were used to predict the probability of being symptomatic based on the accelerometer, work exposure, and individual characteristics predictor variables. Table 1 shows the sensitivity of the models predicting symptoms in the hip/thighs, knees, and ankles/feet and the contributing predictor variables.
The Biomechanical Relevance of Stress Range and Mean Stress in the Analysis of Variable Loading on Musculoskeletal Tissues
Authors: Gallagher Sean , Schall Mark
Published: September 2016

Musculoskeletal tissues usually experience loading referred to in the fatigue failure literature as “repeated stress” or “fluctuating stress” during the performance of occupational tasks. In addition, loads experienced during occupational work often involve highly stress variability. Under these types of loading conditions, the development of cumulative damage is highly influenced by the stress range and the mean stress associated with the loading regimen. This paper describes fatigue failure analysis techniques associated with variable loading situations, including cycle counting techniques, Goodman and Gerber equations for estimation of fatigue life, and the relevance of stress range and mean stress on damage accrual.
Effect of Prior Mental or Physical Fatigue on the Biomechanical Response During a Lifting Task
Authors: Kotowski Susan E. , Niehaus Joseph , Ofat Alyssa , Presnell Michael , Regelski Alena , Rockwell Bradley
Published: September 2016

Repetitive lifting is a requirement in many occupations and often leads to prevalent and costly back injuries. What is unknown is how fatigue, whether mental or physical, occurring before the primary lifting task impacts the biomechanical response during the task. Study participants completed three lifting tasks with prior mental fatigue (Stroop test), prior physical fatigue (running on a treadmill), or no prior fatigue. Electromyography (EMG) was used to measure muscle activity and fatigue, and Borg’s Rating of Perceived Exertion (RPE) was also assessed. Muscle activation data and RPE data indicated that both prior mental and physical fatigue increases muscle activation and perceived exertion.
Case Study: Participatory Ergonomics in Road Construction and an Occupational Perspective of Health
Authors: Pazell Sara , Burgess-Limerick Robin , Horberry Tim
Published: September 2016

Road construction comprises high-risk work activity including risks for collision, musculoskeletal disorder, and slips, trips and falls. A participatory ergonomics project was hosted after compelling field observations were made. A manual task involving roll-out of multi-laminate tape was redesigned with the fabrication of a customized trolley. A human-centered design process was engaged (The Design for Operability and Maintainability Technique) and the project outcomes were reviewed according to an Occupational Perspective of Health, a spectrum of safety through to productivity (or “doing – being – becoming – belonging”). Critical success factors of the project are described, also, to inform activity that may sustain a participatory ergonomics and human-centered design practice.
Supporting Participatory Practices in Ship Design and Construction – Challenges and Opportunities
Authors: Mallam Steven C. , Lundh Monica , MacKinnon Scott N.
Published: September 2016

The maritime shipping industry is a safety-critical domain where onboard work organization continues to evolve with advancing technologies. Recent research has revealed that altering operational conditions and task demands are not supported or optimized by typical onboard working environments. The application of ergonomics and participatory design practices in ship design and construction is generally not well supported by regulation or implemented by designers. The purpose of this paper is to systematically analyse the potential of practical application of ergonomics and participatory design practices in ship design and construction. SWOT (strengths, weaknesses, opportunities and threats) and PEST (political, economic, social and technological) analyses were used to investigate the internal, and of particular interest, the external macro-environmental factors of the shipping industry which influence the success of ergonomics applications in ship development processes.
Center of mass location of stick vacuum cleaners affects physical demands during floor vacuuming
Authors: Choi Seobin , Shin Gwanseob
Published: September 2016

Compact sized and battery powered stick vacuum cleaners are becoming popular as replacements for full-size canister or upright vacuums. While the center of mass (CoM) of typical stick vacuum cleaners is located near the brush, recent products have the main components near the handle of the cleaner, which moves the CoM towards the handle. The aim of this study was to compare physical demands of the two types of stick vacuum cleaners. Sixteen participants conducted push/pull vacuuming strokes on two different floors at two different speeds with stick cleaner models of different CoM while the electromyography of six upper extremity muscles were collected. Results show that high CoM cleaner caused greater (p<0.05) activity of the biceps (28.5% vs. 22.3% of maximum capacity), deltoid (21.1% vs. 19.4%) and shoulder muscles (8.0% vs. 7.1%) compared to low CoM cleaner, indicating that the high CoM cleaners may produce greater physical stress and muscle fatigue compared to low CoM cleaners.
Muscle Oxygenation Correlates of Handgrip Fatigue with Obesity
Authors: Mehta Ranjana K. , Rhee Joohyun , Cavuoto Lora
Published: September 2016

The aims of this study were to determine obesity-related muscle oxygenation correlates of submaximal fatigue, across 20, 40, 60, and 80% of maximum voluntary contractions (MVC). 72 normal weight, overweight and obese adults, matched by gender, performed the four endurance tests on different days. Muscle oxygenation of the flexor and extensor carpi radialis were measured by near infrared spectroscopy and endurance time was recorded for each test. The findings indicated that obesity-related reduction in handgrip endurance was evident at low force contraction levels. Obesity was associated with impaired muscle oxygenation; however, the changes were independent of force contraction levels. Muscle oxygenation did not directly limit the time to failure for endurance tests at higher force levels. Thus, it is likely that factors other than local metabolic and hemodynamic changes impede fatigue resistance at higher force contraction levels.
Digital Human Modeling of Obese & Aging Workers in Automotive Manufacturing
Authors: Ngo Sriya , Sommerich Carolyn M. , Luscher Anthony F.
Published: September 2016

Digital human modeling has become an important tool in several industries, particularly in manufacturing. However, when these models are used, their use is often limited to “50th percentile” male and female models. The dimension is typically not explicitly named, but is inferred to be stature. The U.S. population is growing in size and age, which increases the range of abilities and limitations of the workforce. The objective of this study was to improve the understanding of how to better create and utilize digital human models that reflects a worker population that is diverse in stature, weight, and age. Previous research has yet to adequately incorporate this range of human population diversity into human digital modeling used in industrial modeling applications. Through use of CATIA Delmia (Dassault Systémes), a popular digital human modeling software tool, this research investigates how modeling software can be utilized in a number of ways to depict variations in worker size and age, for planning manual assembly and other work tasks. Validation of the models was assessed through filming, questionnaires, and interviews of workers in an automobile assembly plant. This research was able to show the limitations of current applications of human modeling with respect to the age, weight, and stature of a diverse worker population and provides suggestions for how to improve modeling.
Measurement and Application of 3D Ear Images For Earphone Design
Authors: Lee Wonsup , Jung Hayoung , Bok Ilgeun , Kim Chulwoo , Kwon Ochae , Choi Teukgyu , You Heecheon
Published: September 2016

Detail anthropometric dimensions and a 3D shape of the outer-ear are applicable to design ear-related products such as an earphone. However, 3D scanning of the ear part is quite difficult due to a complex shape of the ear, also detailed ear dimensions which are needed to be measured for earphone design were not identified in previous studies. This study collected 3D scan images of the whole outer-ear from 100 Korean participants (50 females and 50 males) aged 20 to 59, then measured their detailed ear dimensions for earphone design. The pinna part was directly 3D scanned; and complex shape of the concha and acoustic canal parts were cast by applying an ear casting tool, then the cast was scanned in 3D. 13 ear dimensions were measured by applying an ear measurement system coded using Matlab. Both 3D ear scans and ear measurements were applied to design some earphone parts (earphone-head, ear-band, ear-tip) in this study.
Ergonomic Evaluation on Handle Designs of Vacuum Cleaner
Authors: Lee Nahyeon , Lee Seunghoon , Lee Baekhee , Jung Hayoung , You Heecheon
Published: September 2016

Previous studies of handle evaluation have mainly examined optimal sizes of simple-shape (e.g., cylindrical) handles. The present study was intended to identify main design factors and to evaluate usability of vacuum cleaner handles which have complex design features. Upper part length (UL), midpoint-pipe centerline distance (MCD), tilt angle (TA), and cross-section upper part curvature radius (UR) of handle were determined as main design factors of vacuum cleaner handle. The effects of the four design factors on motion, muscular effort, and satisfaction in a front-to-back vacuuming task were evaluated using 6 handles by 36 participants aged in 20s to 50s. The ergonomic evaluation showed that the comfortable range of motion (CROM) deviations of small TAs (40.6° ~ 46.6°) were 1.8% higher significantly in abduction/adduction of shoulder, 2.6% lower in flexion/extension of shoulder, 1.6% lower in ulnar/radial deviation of wrist compared to those of large TAs (56.6° ~ 64.7°). Furthermore, % MVC < 5% of small URs (4.9 ~ 13.3 mm) was 1.7% higher significantly in deltoid, 3.0% higher in flexor carpi radialis compared to those of large URs (17.8 ~ 19.9 mm). Significantly higher satisfaction levels were reported in long ULs (118.4 ~ 154.8 mm) than short ULs (68.7 ~ 98.2 mm) and in short MCDs (3.0 ~ 25.8 mm) than long MCDs (39.4 ~ 78.4 mm). The results of this study can be used to develop ergonomic handles of vacuum cleaner.
How Fitness Trackers Facilitate Health Behavior Change
Authors: Wu Qinge , Sum Kelli , Nathan-Roberts Dan
Published: September 2016

Fitness trackers have broadened the healthcare ecosystem and made self-tracking everyday physical activities possible. Features like heart rate monitoring can help detect health ailments, yet there is little evidence that suggests tracking health indicators and physical activities leads to long-term health behavior change. This proceeding analyzes areas of Human Factors that could be used to increase long-term user engagement. Feedback, information display, and specific design principles and case studies are discussed.
Towards a Visual Vocabulary for Privacy Concepts
Authors: Motti Vivian Genaro , Caine Kelly
Published: September 2016

Designing privacy controls that are intuitive for end users involves several challenges. Graphic representations could certainly contribute to tackle such challenges, however, a visual vocabulary for privacy solutions is currently lacking. To contribute to that end, in this paper we report a review of online images related to privacy. We identify graphic representations that illustrate privacy objects, mechanisms and actions, and categorize them according to the concepts covered. Seeking to develop a set of icons to illustrate privacy concepts, we analyze online contents publicly available from social media and extract representations that commonly refer to privacy concepts. The contributions of this paper include: (1) a set of graphics that represent privacy mechanisms, objects and actions; and (2) a vocabulary for such graphic representation. The evidence is drawn from the analysis and discussion of 241 images selected by the authors from ten online image repositories.
Using Modern Social Network Techniques to Expand Link Analysis in a Nuclear Reactor Console Redesign
Authors: Dinakar Swaroop , Tippey Kathryn G. , Roady Trey , Edery Julien , Ferris Thomas K.
Published: September 2016

As part of the Nuclear Regulatory Commission’s recertification of Texas A&M University’s AGN-201M nuclear reactor, a human factors analysis was performed to evaluate the drawbacks of the current system and make design recommendations for a new console layout. The process involved three phases. Background development consisted of a literature review and expert interviews (both structured and unstructured). Process analysis was performed using hierarchical task analysis, critical incident analysis, and heuristic usability walkthroughs. Control panel redesign utilized an expanded version of link analysis through adding modern social networking analysis techniques. While social network analysis has previously been used for design, particular emphasis in this paper is placed on the novel application of faction and centrality analysis to identify group categories for console redesign.
Structure Matters: Effects of Semantic Relatedness and Proximity on Consumer Search and Integration Tasks
Authors: Grishin John , Gillan Douglas J.
Published: September 2016

Information displays should be clear and easily understood. This research examined whether principles developed by Kosslyn (1989) and Carswell and Wickens (1987) for charts, graphs, and object displays could be extended, or adapted, to another type of display, the food item package. We hypothesized that a food package on which label items had been arranged according to their similarity, or semantic relatedness, would facilitate better user performance than a package on which label items had been arranged in other ways. Participants rated the semantic relatedness of 12 label items found on a common food item package. Using multi-dimensional scaling (MDS) outputs from the ratings, we created three versions of a consumer cough drop package: 1) Similarity version—label elements that received higher similarity ratings were depicted closer together than elements with lower similarity ratings, 2) Dissimilarity version—elements that received higher similarity ratings were depicted farther apart than elements with lower similarity ratings, 3) Random version—rating values were randomly assigned to the pairs of elements. We tested user performance on search tasks and integrative tasks on each of the three versions. We hypothesized that the Similarity version would produce the best user performance and the Dissimilarity version would produce the worst. Results only partially supported the hypotheses. On the search tasks, the best performance was achieved on the Similarity and Dissimilarity versions, and the worst on the Random version. On the integrative tasks, the version made no difference in performance. Possible reasons for these results are discussed. Similar results by Fitts and Deininger (1954) and Morin and Grant (1955) suggest that performance on tasks are superior when the relationships are in an ordered structure, rather than randomly assigned, possibly because ordered structures make possible the development of search strategies, whereas random arrangements do not.
A Conversation with National Academy of Engineering President Dan Mote
Authors: Mote C. D. , Imada A. S.
Published: September 2016

Learn directly from the president of the National Academy of Engineering about the NAE’s Grand Challenges for the 21st Century, which identifies 14 major issues confronting our future. The NAE Grand Challenges have been embraced widely across research, educational, and professional communities as a way to structure our thinking, direct our resources, and devote our energies going forward.

In this conversational session, Imada will pose questions to President Mote about the thinking that went into the Grand Challenges, progress being made, and, most important, how human factors/ergonomics can contribute to addressing these issues. As HFES President William Marras has suggested, the Grand Challenges could be an important platform from which we can realize our Society's vision to be more relevant and make a significant contribution to the world.

We encourage you to come and learn about these issues and consider this paradigm for guiding future efforts in our field.